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NBME 21 Answers

Block/Question (48.0 difficulty score)
A 24-year-old woman with sickle cell disease ...
Serum parvovirus B19 IgM antibody test๐Ÿ”

Block/Question (58.4 difficulty score)
A 6-month-old girl is brought to the ...
GM2๐Ÿ”

Block/Question (60.0 difficulty score)
An investigator is studying the efficacy of ...
Flagellin๐Ÿ”

Block/Question (26.2 difficulty score)
A 67-year-old man comes to the emergency ...
Translation๐Ÿ”

Block/Question (49.1 difficulty score)
A 45-year-old woman is brought to the ...
Absorption atelectasis๐Ÿ”

Block/Question (60.3 difficulty score)
A normal-appearing 17-year-old girl has never ...
Androgen insensitivity syndrome๐Ÿ”

Block/Question (22.5 difficulty score)
A 30-year-old primigravid woman at 22 weeks' ...
Listeria monocytogenes ๐Ÿ”

Block/Question (26.4 difficulty score)
A 52-year-old woman is admitted to the ...
Speak with the two gynecologists to attempt to coordinate care๐Ÿ”

Block/Question (14.3 difficulty score)
A 53-year-old woman who underwent an ...
Breast: antagonist; Uterus: partial agonist๐Ÿ”

Block/Question (26.7 difficulty score)
A 34-year-old woman is brought to the ...
Primary metabolic acidosis with increased anion gap๐Ÿ”

Block/Question (36.8 difficulty score)
A 27-year-old primigravid woman at 34 weeks' ...
Schistocytes๐Ÿ”

Block/Question (41.8 difficulty score)
A 25-year-old nulligravid woman comes to the ...
Endometrial hyperplasia๐Ÿ”

Block/Question (38.7 difficulty score)
A 25-year-old man develops shortness of ...
Decreased alveolar Po2๐Ÿ”

Block/Question (19.1 difficulty score)
A 21-year-old man is brought to the emergency ...
Streptococcus pneumoniae๐Ÿ”

Block/Question (43.9 difficulty score)
A 35-year-old man comes to the physician ...
Increased vascular permeability๐Ÿ”

Block/Question (58.2 difficulty score)
A 43-year-old man comes to the physician for ...
Aortic๐Ÿ”

Block/Question (78.2 difficulty score)
A 7-year-old girl is brought to a clinic in a ...
Methionine๐Ÿ”

Block/Question (22.9 difficulty score)
A 61-year-old woman is brought to the ...
Donepezil๐Ÿ”

Block/Question (43.7 difficulty score)
A 22-year-old man has had frequent episodes ...
C1 esterase inhibitor (binds activated C1r, C1s)๐Ÿ”

Block/Question (28.4 difficulty score)
A 10-year-old girl develops fever, malaise, ...
Retrograde transport through nerves๐Ÿ”

Block/Question (24.4 difficulty score)
A 40-year-old man with type 2 diabetes ...
Stimulation of the peroxisome proliferator-activated receptor ฮณ๐Ÿ”

Block/Question (36.5 difficulty score)
A 36-year-old man with AIDS elects to ...
Chemokine๐Ÿ”

Block/Question (45.2 difficulty score)
A 59-year-old man comes to the physician ...
Foci of keratinization๐Ÿ”

Block/Question (57.8 difficulty score)
A 23-year-old man drinks alcohol heavily on a ...
Fatty change๐Ÿ”

Block/Question (44.7 difficulty score)
A 28-year-old man is brought to the emergency ...
Dissecting aneurysm๐Ÿ”

Block/Question (35.8 difficulty score)
A 62-year-old man who is a farmer comes to ...
Actinic keratosis๐Ÿ”

Block/Question (26.8 difficulty score)
A 60-year-old man is brought to the emergency ...
Urethral disruption๐Ÿ”

Block/Question (62.8 difficulty score)
A 47-year-old man is brought to the emergency ...
Mixed venous oxygen tension๐Ÿ”

Block/Question (15.5 difficulty score)
A 34-year-old man comes to the physician ...
Cluster headache๐Ÿ”

Block/Question (43.9 difficulty score)
A newborn has female external genitalia and a ...
Dihydrotestosterone๐Ÿ”

Block/Question (52.1 difficulty score)
A 30-year-old woman comes to the office for a ...
Linoleic acid๐Ÿ”

Block/Question (59.9 difficulty score)
A 50-year-old man has had progressive dyspnea ...
Usual interstitial pneumonitis๐Ÿ”

Block/Question (23.7 difficulty score)
A 30-year-old man comes to the physician ...
Varicella-zoster virus infection๐Ÿ”

Block/Question (57.1 difficulty score)
A 30-year-old man develops urinary ...
Pelvic nerves๐Ÿ”

Block/Question (31.4 difficulty score)
A 7-year-old boy is brought to the physician ...
Increased blood lead๐Ÿ”

Block/Question (60.0 difficulty score)
A 51-year-old woman comes to the physician ...
Area labeled 'B' (Parietal cell)๐Ÿ”

Block/Question (20.5 difficulty score)
A 35-year-old man with diabetic ketoacidosis ...
Serum potassium concentration๐Ÿ”

Block/Question (22.6 difficulty score)
A 47-year-old woman with aplastic anemia is ...
Amphotericin B๐Ÿ”

Block/Question (34.7 difficulty score)
A 33-year-old woman comes to the physician ...
Genital herpes๐Ÿ”

Block/Question (32.4 difficulty score)
A physician prescribes a recently marketed ...
Phase 4๐Ÿ”

Block/Question (30.0 difficulty score)
A 35-year-old woman comes to the physician ...
Uroporphyrinogen decarboxylase๐Ÿ”

Block/Question (39.0 difficulty score)
A 36-year-old woman undergoes a total ...
Hyperplasia๐Ÿ”

Block/Question (36.9 difficulty score)
A 52-year-old man is brought to the emergency ...
Histamine๐Ÿ”

Block/Question (17.7 difficulty score)
A test has been developed to screen for human ...
Predictive value of a positive test๐Ÿ”

Block/Question (43.3 difficulty score)
An 18-year-old man comes to the physician ...
Pyruvate kinase๐Ÿ”

Block/Question (29.2 difficulty score)
A 66-year-old man is brought to the emergency ...
Lipopolysaccharide stimulation of toll-like receptor๐Ÿ”

Block/Question (56.2 difficulty score)
A 26-year-old woman (III-2) comes to the ...
50% in females but near 0 in males๐Ÿ”

Block/Question (32.9 difficulty score)
A 44-year-old man is admitted to the hospital ...
Increasing cGMP๐Ÿ”

Block/Question (37.1 difficulty score)
An 80-year-old woman comes to the emergency ...
Hydrochlorothiazide๐Ÿ”

Block/Question (47.0 difficulty score)
A photograph is shown of a myelin-stained ...
Loss of sensation to vibration over both feet๐Ÿ”

Block/Question (16.6 difficulty score)
A 27-year-old man comes to the physician for ...
Schizoid๐Ÿ”

Block/Question (40.5 difficulty score)
A 4-year-old girl is conscious but unable to ...
Pseudocholinesterase deficiency๐Ÿ”

Block/Question (52.4 difficulty score)
A 17-year-old boy returns to the locker room ...
Apocrine๐Ÿ”

Block/Question (30.6 difficulty score)
An 18-year-old woman comes to the office ...
Extensor carpi radialis brevis๐Ÿ”

Block/Question (71.2 difficulty score)
A 2-week-old male newborn has a patent ductus ...
Higher than normal left ventricular cardiac output๐Ÿ”

Block/Question (55.4 difficulty score)
A 38-year-old woman comes to the physician ...
Serum calcium concentration๐Ÿ”

Block/Question (31.0 difficulty score)
A 50-year-old man with rheumatoid arthritis ...
Anemia of chronic disease๐Ÿ”

Block/Question (53.9 difficulty score)
A 55-year-old man is diagnosed with renal ...
Cortex๐Ÿ”

Block/Question (28.0 difficulty score)
A 40-year-old man is brought to the emergency ...
Metabolic acidosis and respiratory acidosis๐Ÿ”

Block/Question (30.8 difficulty score)
A 42-year-old woman comes to the physician ...
Rosacea๐Ÿ”

Block/Question (36.1 difficulty score)
A 22-year-old woman, gravida 1, para 1, is ...
Internal iliac๐Ÿ”

Block/Question (69.7 difficulty score)
A 66-year-old woman comes to the physician ...
Diverticulitis๐Ÿ”

Block/Question (41.2 difficulty score)
A 53-year-old woman with gastroesophageal ...
Omeprazole๐Ÿ”

Block/Question (78.2 difficulty score)
A 30-year-old woman comes to the office ...
Abnormal brain development๐Ÿ”

Block/Question (59.9 difficulty score)
A 48-year-old man is brought to the emergency ...
Splenic and left renal๐Ÿ”

Block/Question (54.4 difficulty score)
A 34-year-old woman comes to the physician ...
Atrioventricular bundle๐Ÿ”

Block/Question (29.1 difficulty score)
Scientists have identified the flawed gene ...
Mismatch repair๐Ÿ”


Block/Question (43.9 difficulty score)
A 3-year-old boy who recently immigrated to ...
Increased proportions of osteoid๐Ÿ”

Block/Question (48.0 difficulty score)
A 14-year-old girl is brought to the ...
Trichotillomania๐Ÿ”

Block/Question (54.4 difficulty score)
A 35-year-old woman undergoes flexible ...
Superior to the superior concha๐Ÿ”

Block/Question (36.0 difficulty score)
A 33-year-old woman, gravida 4, para 4, is ...
Transfusion-related acute lung injury๐Ÿ”

Block/Question (31.2 difficulty score)
A 4-year-old boy with chronic granulomatous ...
Macrophages producing interleukin-1 (IL-1)๐Ÿ”

Block/Question (61.2 difficulty score)
A 65-year-old man dies in a motor vehicle ...
Squamous cell carcinoma๐Ÿ”

Block/Question (20.4 difficulty score)
A 54-year-old man comes to the physician for ...
Area labeled 'F' (Efferent arteriole)๐Ÿ”

Block/Question (43.7 difficulty score)
A healthy 32-year-old woman at 35 weeks' ...
Birth canal reflex๐Ÿ”

Block/Question (14.3 difficulty score)
A 47-year-old woman with psoriasis comes to ...
โ€œMost people find it difficult to stick to a routine. How did you do?โ€๐Ÿ”

Block/Question (15.8 difficulty score)
A 64-year-old woman with type 2 diabetes ...
Gemfibrozil๐Ÿ”

Block/Question (63.2 difficulty score)
A healthy 25-year-old man is participating in ...
Alanine๐Ÿ”


Block/Question (54.2 difficulty score)
A 37-year-old man is brought to the emergency ...
Intercostal๐Ÿ”

Block/Question (22.7 difficulty score)
A 17-year-old boy has the acute onset of ...
Lymphocytes๐Ÿ”

Block/Question (58.5 difficulty score)
A 68-year-old man comes to the physician ...
Libido: normal; Nocturnal erections: normal๐Ÿ”

Block/Question (49.1 difficulty score)
A 28-year-old man is brought to the emergency ...
Inferior rectus and inferior oblique๐Ÿ”

Block/Question (66.8 difficulty score)
A 4-month-old female infant is brought to the ...
Hyponatremia๐Ÿ”

Block/Question (16.9 difficulty score)
An investigator is conducting a study of ...
Enfuvirtide๐Ÿ”

Block/Question (28.3 difficulty score)
A 17-year-old boy is evaluated for ...
Craniopharyngioma๐Ÿ”

Block/Question (14.7 difficulty score)
A 63-year-old man with bladder cancer starts ...
Tubulin polymerization stabilization๐Ÿ”

Block/Question (48.2 difficulty score)
A 64-year-old man with bronchospastic ...
Enhanced action of the agonist at ฮฒ-adrenergic receptors๐Ÿ”

Block/Question (31.5 difficulty score)
Acetaminophen and nonsteroidal ...
Prostaglandin E2๐Ÿ”

Block/Question (31.2 difficulty score)
A 75-year-old woman has the sudden onset of ...
Posterior inferior cerebellar๐Ÿ”

Block/Question (19.4 difficulty score)
A 26-year-old man with HIV infection comes to ...
Penicillin๐Ÿ”

Block/Question (35.5 difficulty score)
A 78-year-old woman is brought to the ...
Embolectomy๐Ÿ”

Block/Question (25.7 difficulty score)
A 75-year-old man has the sudden onset of ...
Parietal lobe, left๐Ÿ”

Block/Question (33.2 difficulty score)
A 3-year-old boy is brought to the emergency ...
Synthesis of factor X (Stuart factor)๐Ÿ”

Block/Question (36.6 difficulty score)
An 8-year-old girl is brought to the ...
โ€œYour daughterโ€™s development is normal.โ€๐Ÿ”

Block/Question (41.7 difficulty score)
A 55-year-old woman comes to the physician ...
Increased parathyroid hormone๐Ÿ”

Block/Question (37.9 difficulty score)
A 75-year-old man has fever, back pain, and ...
Enterococcus faecalis๐Ÿ”

Block/Question (25.3 difficulty score)
A 6-year-old girl is brought to the physician ...
Poxvirus๐Ÿ”

Block/Question (51.1 difficulty score)
A 65-year-old woman comes to the emergency ...
Lung and common carotid artery๐Ÿ”

Block/Question (15.9 difficulty score)
A 30-year-old woman develops dimness of vision
Ethambutol๐Ÿ”

Block/Question (35.0 difficulty score)
A 40-year-old man with interstitial pulmonary ...
Increased radial traction on airways๐Ÿ”

Block/Question (14.9 difficulty score)
A 55-year-old African American man with ...
Tell the patient that he can change his mind about participating๐Ÿ”

Block/Question (45.2 difficulty score)
A clinical trial is conducted to compare the ...
Surgical procedure group: 400; Medical management group: 400๐Ÿ”

Block/Question (45.2 difficulty score)
A 70-year-old woman is found to have ...
Candida albicans ๐Ÿ”

Block/Question (37.2 difficulty score)
A 40-year-old African American woman comes to ...
1,25-Dihydroxycholecalciferol๐Ÿ”

Block/Question (50.4 difficulty score)
A 65-year-old man comes to the physician ...
DNA fragmentation๐Ÿ”

Block/Question (44.6 difficulty score)
A 55-year-old woman is brought to the ...
Mammillary bodies๐Ÿ”

Block/Question (35.5 difficulty score)
A 75-year-old woman is brought to the ...
Shrunken eosinophilic (red) neurons๐Ÿ”

Block/Question (22.3 difficulty score)
A 30-year-old man has had intermittent severe ...
Cysteine๐Ÿ”

Block/Question (65.0 difficulty score)
A 50-year-old man is found dead in bed at ...
Arrhythmia๐Ÿ”

Block/Question (41.8 difficulty score)
A 55-year-old man with hypertension comes to ...
Left renal artery atherosclerosis๐Ÿ”

Block/Question (35.5 difficulty score)
A 40-year-old woman comes to the physician ...
Antagonizes VLDL-cholesterol secretion๐Ÿ”

Block/Question (18.8 difficulty score)
A 35-year-old man is brought to the emergency ...
Activation of adenylyl cyclase๐Ÿ”

bilirubin
Block/Question (43.2 difficulty score)
A 47-year-old man has jaundice. Laboratory ...
Obstruction of the bile duct๐Ÿ”

Block/Question (60.4 difficulty score)
A 16-year-old boy is brought to the physician ...
Exercise-induced asthma๐Ÿ”

Block/Question (39.1 difficulty score)
A 66-year-old woman with pancreatic cancer ...
Short gastric๐Ÿ”

Block/Question (33.9 difficulty score)
An 83-year-old man comes to the physician ...
Bullous pemphigoid antigen๐Ÿ”

Block/Question (43.0 difficulty score)
A 25-year-old woman develops increasing ...
Four-chamber dilation๐Ÿ”

Block/Question (51.0 difficulty score)
A 68-year-old woman has had a fever and ...
Reactive granulocytosis๐Ÿ”

Block/Question (48.1 difficulty score)
A screening program is instituted for ...
10%๐Ÿ”

Block/Question (36.4 difficulty score)
A 9-year-old boy has mild mental retardation ...
Rhabdomyoma๐Ÿ”

Block/Question (37.7 difficulty score)
A 43-year-old woman dies after a 10-year ...
Area labeled โ€˜Cโ€™ (Caudate nucleus)๐Ÿ”

Block/Question (49.7 difficulty score)
Diastolic blood pressures are obtained in two ...
Median of group Y: higher; Mode of group Y: higher๐Ÿ”

Block/Question (44.8 difficulty score)
A 32-year-old woman comes to the physician ...
Dysplastic nevi๐Ÿ”

Block/Question (43.2 difficulty score)
A 19-year-old woman comes to the office ...
Descending colon๐Ÿ”

Block/Question (39.0 difficulty score)
A 55-year-old woman with a benign nodule in ...
External carotid๐Ÿ”

Block/Question (69.0 difficulty score)
A 1-year-old girl is admitted to the hospital ...
Disruption of the secondary structure of collagen molecules๐Ÿ”


Block/Question (45.0 difficulty score)
A 41-year-old man comes to the physician ...
Abduction of the upper extremity๐Ÿ”

Block/Question (48.2 difficulty score)
A 28-year-old woman at 18 weeks' gestation ...
Free T4๐Ÿ”

Block/Question (24.0 difficulty score)
A 72-year-old man comes to the physician ...
Bleomycin๐Ÿ”

Block/Question (58.2 difficulty score)
Left radial arterial and venous blood samples ...
HCO3โˆ’ transported in the plasma๐Ÿ”

Block/Question (39.1 difficulty score)
A 39-year-old woman with rheumatoid arthritis ...
Membranous glomerulonephritis๐Ÿ”

Block/Question (56.5 difficulty score)
A 63-year-old woman comes to the physician ...
Increased resting cardiac output๐Ÿ”

Block/Question (67.0 difficulty score)
Which of the following best explains why the ...
Myeloma cells do not have membrane-bound surface immunoglobulin๐Ÿ”

Block/Question (64.5 difficulty score)
A 5-year-old boy who has homocystinuria ...
The line on the graph labeled โ€˜Bโ€™๐Ÿ”

Block/Question (34.4 difficulty score)
A 28-year-old man develops a temperature of ...
Granulocyte colony-stimulating factor๐Ÿ”

Block/Question (26.5 difficulty score)
A 74-year-old woman with mild dementia is ...
Inability to understand the severity and prognosis of her medical condition๐Ÿ”

Block/Question (37.8 difficulty score)
A 65-year-old woman undergoes surgical repair ...
Area labeled โ€˜Aโ€™ (Cranial nerve 3)๐Ÿ”

Block/Question (35.8 difficulty score)
A 75-year-old woman comes to the physician's ...
Major depressive disorder๐Ÿ”

Block/Question (34.0 difficulty score)
A 27-year-old primigravid woman at 39 weeks' ...
Shoulder dystocia๐Ÿ”

Block/Question (20.8 difficulty score)
An undernourished 70-year-old man has fever, ...
Interferon-ฮณ๐Ÿ”

Block/Question (40.9 difficulty score)
A 23-year-old woman develops persistent ...
Stabilization of mast cell membranes๐Ÿ”

Block/Question (60.8 difficulty score)
A 28-year-old man comes to the physician for ...
Fructose๐Ÿ”

Block/Question (16.6 difficulty score)
A 38-year-old woman comes to the physician ...
Patent foramen ovale๐Ÿ”

Block/Question (25.6 difficulty score)
A 48-year-old man comes to the physician ...
Increased intestinal iron absorption๐Ÿ”

Block/Question (29.0 difficulty score)
A 29-year-old woman comes to the physician ...
Baclofen๐Ÿ”

cell_bio cell_transport cell_trafficking
Block/Question (51.9 difficulty score)
The gene that codes for a protein normally ...
Deletion of a hydrophobic amino acid sequence from the N terminus๐Ÿ”

Block/Question (58.1 difficulty score)
A 32-year-old woman comes to the emergency ...
Arthropod vector๐Ÿ”

Block/Question (45.5 difficulty score)
A 50-year-old woman has azotemia. Renal ...
Uterine cervix๐Ÿ”

Block/Question (43.7 difficulty score)
A 23-year-old woman comes to the student ...
Obliterative endarteritis with lymphocytes and plasma cells๐Ÿ”

Block/Question (23.8 difficulty score)
A study was performed that evaluated the ...
Odds ratio๐Ÿ”

Block/Question (61.7 difficulty score)
The FOXO transcription factor responds to ...
Nuclear/cytoplasmic shuttling: yes;
Serine phosphorylation: yes
Ubiquitin-mediated proteolysis: no
๐Ÿ”


Block/Question (50.8 difficulty score)
An 11-year-old boy has had persistent pain in ...
Lung๐Ÿ”

Block/Question (38.8 difficulty score)
A 55-year-old man comes to the physician ...
Cortisol๐Ÿ”

Block/Question (44.1 difficulty score)
A 14-year-old boy is brought to the physician ...
Inhaled glue๐Ÿ”

FA_missing
Block/Question (47.7 difficulty score)
A 70-year-old woman has had recurrent ...
Euthyroid sick syndrome๐Ÿ”

porphyria phototherapy
Block/Question (38.4 difficulty score)
A 60-year-old woman with psoriasis comes to ...
Porphyria cutanea tarda๐Ÿ”

renal SIADH hyponatremia
Block/Question (45.1 difficulty score)
A 64-year-old man is evaluated for cough, ...
Hyponatremia๐Ÿ”


Block/Question (35.7 difficulty score)
A 24-year-old man with a history of drug ...
Heroin๐Ÿ”

Block/Question (51.1 difficulty score)
A 4-month-old boy is diagnosed with a rare ...
Dilated rough endoplasmic reticulum๐Ÿ”

Block/Question (52.9 difficulty score)
A 25-year-old woman has a 3-week history of ...
Autoantibodies against platelet glycoproteins๐Ÿ”

Block/Question (55.8 difficulty score)
A 5-year-old boy is brought to the physician ...
Lack of choroidal pigment deposition in the macula๐Ÿ”

Block/Question (19.9 difficulty score)
A 40-year-old woman who had pneumonia due to ...
Surfactant๐Ÿ”

Block/Question (29.9 difficulty score)
A 48-year old man is referred for evaluation ...
Increase in width๐Ÿ”

Block/Question (12.0 difficulty score)
A previously healthy 4-week-old male newborn ...
Pyloric stenosis๐Ÿ”

Block/Question (34.2 difficulty score)
A 45-year-old woman comes to the emergency ...
Hepatopancreatic ampulla๐Ÿ”

Block/Question (56.5 difficulty score)
A 7-month-old boy is brought to the physician ...
46,XY๐Ÿ”

Block/Question (11.3 difficulty score)
A 47-year-old man is treated with colchicine ...
Tubulin polymerization๐Ÿ”

Block/Question (44.4 difficulty score)
A 57-year-old woman is brought to the ...
Ninth๐Ÿ”

Block/Question (58.6 difficulty score)
An investigator is studying the regulation of ...
Intravenous infusion of 0.9% saline for 5 minutes๐Ÿ”

Block/Question (34.9 difficulty score)
A 56-year-old man undergoes a renal ...
IgG plus complement๐Ÿ”

Block/Question (62.6 difficulty score)
An 80-year-old woman cannot concentrate her ...
2.0๐Ÿ”

Block/Question (25.0 difficulty score)
The immunosuppressive agent cyclosporin A ...
Interleukin-2 (IL-2) gene transcription๐Ÿ”


Block/Question (28.1 difficulty score)
A 56-year-old man undergoes surgical ...
Release of cholecystokinin๐Ÿ”

Block/Question (31.8 difficulty score)
A 22-year-old man comes to the physician ...
Formation of destructive free radicals๐Ÿ”

Block/Question (35.6 difficulty score)
A 5-year-old boy is admitted to the hospital ...
ApoC-II๐Ÿ”

Block/Question (33.0 difficulty score)
A 48-year-old woman comes to the physician ...
Paracrine stimulation of osteoclasts by osteoblasts๐Ÿ”

Block/Question (14.7 difficulty score)
A 19-year-old college student says he hears ...
Risperidone๐Ÿ”

Block/Question (49.2 difficulty score)
A female newborn delivered at 26 weeks' ...
Retina๐Ÿ”

Block/Question (47.4 difficulty score)
A healthy 8-year-old boy is brought to the ...
Stimulation of the release of biogenic amine neurotransmitters๐Ÿ”

Block/Question (25.1 difficulty score)
A 50-year-old woman is admitted to the ...
Didanosine (ddI)๐Ÿ”

Block/Question (55.7 difficulty score)
A 45-year-old man comes to the physician ...
Chondrosarcoma๐Ÿ”

Block/Question (46.1 difficulty score)
A 66-year-old right-handed woman develops the ...
Area labeled 'B' (Internal capsule)๐Ÿ”

Block/Question (30.9 difficulty score)
A 62-year-old woman is brought to the ...
Instruct the patient to keep notes and lists to help her memory๐Ÿ”

Block/Question (46.6 difficulty score)
A 46-year-old man comes to the physician ...
1/15๐Ÿ”

Block/Question (49.5 difficulty score)
A study is conducted to assess the normal ...
500 Men from a list of patients scheduled to be examined by a urologist๐Ÿ”

Block/Question (15.8 difficulty score)
A 66-year-old man with stage IV colon cancer ...
Loperamide๐Ÿ”

Block/Question (20.6 difficulty score)
A 20-year-old primigravid woman at 12 weeks' ...
Multifactorial๐Ÿ”

Block/Question (24.1 difficulty score)
A 4-year-old boy falls and lacerates his ...
Formation of fibrin clot๐Ÿ”

renal diuretics GFR
Block/Question (37.7 difficulty score)
A 28-year-old woman with chronic renal ...
Furosemide๐Ÿ”

neuro pharm magnesium
Block/Question (64.4 difficulty score)
During an experiment, an investigator ...
NMDA receptors are blocked by Mg2+ at the resting membrane potential๐Ÿ”

process_of_elimination Li_Fraumeni p53
Block/Question (44.2 difficulty score)
A 14-year-old girl is brought to the ...
TP53 ๐Ÿ”

Block/Question (23.2 difficulty score)
While lifting weights, a 24-year-old man ...
Strangulation๐Ÿ”

Block/Question (36.6 difficulty score)
A 75-year-old man with dementia, Alzheimer ...
Encourage the family to come to a consensus based on their perception of the patient's wishes๐Ÿ”

Block/Question (40.4 difficulty score)
A 76-year-old man comes to the physician ...
Left thalamus๐Ÿ”

Block/Question (19.6 difficulty score)
A 19-year-old woman is brought to the ...
Scaphoid๐Ÿ”

Recent comments ...

... nosancuck made a comment on nbme21/block1/q#5 (A 45-year-old woman is brought to the emergency...)
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hrBu tle em llte yuo a lli cerets

EPEP snvetrpe tcseastlAie KAA dat NUGL LCSLOEAP

otnD be niwryor boaut maonrd owsrd yeth sput ni fornt of teh HGIH YEDIL oens

hungrybox  literally LOL'd lmao I love this +13
... assoplasty made a comment on nbme21/block3/q#31 (A 28-year-old woman at 18 weeks' gestation has...)
 +64 
submitted by assoplasty(92)
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I ntkhi het pcotecn eyhteโ€™r etgstni si het nrecedasi GTB levsle ni nacypegn,r adn nto sutj osytiiremdhyprh ni ele.rang

nhWe gnsnreeic rfo iyo/mhyp,dyrprosihthe THS lelsve ear SWYAAL reyerailepflnt dhcceke scbueea ehty ear orme iesietnsv ot mtuein fdfneesriec in 3.TT4/ fentO timse STH lvslee can meesnradtot a hcenag vnee hwen 34/TT veells era ni eht llicubansic agern. heT nylo potenixce to ihts oulwd eb ni ynapcenrg dan( I gsesu yambe viler elria?uf I bodtu htye lowud ska itsh ut)ohgh. ihgH gseotner sellev nrtpesev teh leirv romf egrnikab nwod ,TGB landgie to cdrseeani GTB elslve ni the surme. hTis dsbin to efre ,4T sdicgeraen eht tamuno fo bllvaeaia rfee T.4 As a ytpemoraocns eamsim,hcn SHT esllve rea nsealytirtn decesirna dna the ARTE of 4T inpcrotduo is eidanecrs to hlnpseier aesinelb refe T4 leevs.l eewovHr teh TTLOA omtnau fo 4T si iedare.nsc

Teh esoqtniu is gnsika owh to fncmroi eirypsihytordhm ni a ptgnrean ownma --t;&g you ened ot heckc EFRE 4T eleslv s(ceuaeb ehyt dlshou be arlnmo edu to tasnporymoec peno)sr.se ouY onanct kchec THS y(lusula dtelavee in agenpnycr ot mcatpnoees orf raseciedn G)TB, and uyo noncta ehkcc taolt T4 vellse (ilwl be .ie)sredacn Yuo otg eht waners itrgh heiert wya tub I htink tish si a ndreifetf ernsnioga hrwto crnednii,ogs uscaeeb yeth can aks stih cntpoce ni rehto tseotxnc fo ,eesyesm-gtpohirnr nda if they eildst Sโ€œโ€HT sa an answre cehcoi taht lduow be rtconr.cie

hungrybox  Extremely thorough answer holy shit thank u so much I hope you ACE Step 1 +7
arkmoses  great answer assoplasty, I remember goljan talking about this in his endo lecture (dudes a flippin legend holy shit) but it kinda flew over my head! thanks for the break down! +2
whoissaad  you mean total amount of T4 is "not changed"? 2nd para last sentence. +
ratadecalle  @whoissaad, in a normal pregnancy total T4 is increased, but the free T4 will be normal and rest of T4 bound to TBG. If patient is hyperthyroid, total T4 would still be increased but the free T4 would now be increased as well. +1
maxillarythirdmolar  To take it a step further, Goljan mentions that there are a myriad of things circulating in the body, often in a 1:2 ratio of free:bound, so in states like this you could acutally see disruption of this ratio as the body maintains its level of free hormone but further increases its level of bound hormone. Goljan also mentions that you'd see the opposite effect in the presence of steroids and nephrotic syndromes. So you could see decreased total T4 but normal free T4 because the bound amounts go down. +1
lovebug  Amazing answer! THX +
... lnsetick made a comment on nbme21/block2/q#3 (A 17-year-old boy returns to the locker room after...)
 +49 
submitted by lnsetick(90)
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  • ceiAroPn = oyru siptrma emlls elik na AEP
  • eUenRcM = serhtโ€™e no ORMO ni uyro saer cseni eโ€™rheyt lulf fo wxa
  • YRECne-C = when you CEsir,ece uyor oesrp aer CRinYg
  • ceusoSBEa = BESmu si EngSiEP uot of uyro rpoes
hungrybox  as an ape i'm offended +28
dr.xx  stop being an ape. evolutionize! +6
dbg  as a creationist i'm offended +11
maxillarythirdmolar  Also, Tarsal/Meibomian glands are found along the rims of the eyelid and produce meibum +
snripper  So why is it apocrine? The dude is EXERCISING when playing football. +2
qball  The question asks about "the characteristic odor" i.e. body odor coming from the APEocrine glands. The Eccrine glands secrete water and electrolytes. +1
... seagull made a comment on nbme21/block1/q#2 (A 6-month-old girl is brought to the physician...)
 +47 
submitted by seagull(1391)
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! I taeh heset tihw a nniugrb *gn*Fi* apnsiso. hmbsTu up fi oyu eagre

mcl  Amen brother +1
praderwilli  Every morning: "I think i'll go over glycogen storage diseases, lysosomal storage diseases, and dyslipidemias after questions this afternoon." Every afternoon: Nah +28
mcl  oh my god are you me +1
praderwilli  I recently found a program called Pixorize. It's pretty much Sketchy for biochem. Wish I discovered it sooner cuz it has helped for a lot of the painful things like this! +6
burak  Cherry red spot basically means niemann-pick or tay sachs. Two differences between is: 1- No HSM in Tay Sachs, HSM in niemann-pick. 2- Both of them has muscle weakness but there is hyperreflexia in Tay Sachs, but areflexia in niemann pick disease. In stem cell HSM is not described and hyperreflexia noted. +4
abhishek021196  What is HSM? +
mysticsoul  HSM - HepatoSplenoMegaly. Cherry red spots think of Tay Sachs, deficient enzyme - HeXosaminidase A, accumulated substrate GM2 ganglioside. Niemann-Pick - Spingomyelinase, Spingomyelin <- which is not even a choice. FA18 Pg 88 +
lakshmi  Dirty USMLE has an incredible video that makes these super easy to get. +1
djeffs1  @lakshmi Link? +
... drdoom made a comment on nbme21/block3/q#49 (The gene that codes for a protein normally found in...)
 +46 
submitted by drdoom(804)
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ehT entssyhsi of iulvlaryt all eprtsion diAppm-g)&tetRe(N; orccsu ni het m.scytpoal]1[ โ€™atsTh erweh lla oiemrssbo e,ierds tefra l.la seRo,sombi ihhwc ear motyls ujts rRAN 3(2/~ ANrR + 1/3 teoin*rp, yb ,wthieg) rae dbamessle in het nesulcu utb oynl do tiehr ffuts ecno ethy teg ot het ytopsalm.c

For a itperno ot ealev its giaoilnr wohotmne fo eth osoylct nda bceoem a rinetdse of the lunucse ,ro y,yayyyys the pdmnoseclia rul,eutmic it esden to eahv a ttllei gsrtin fo naoim cdsia hwihc tusoh Iโ€œ gnbeol ni eth ucโ€s!neul or Iโ€œ bnegol ni teh dslcnepiamo e!ltiurcโ€um

ostPrein lemtutayli etesddin rof eht ER tnoncia an nualmigyiniveat dneam gstinr fo miano ascid onnkw as gslaโ€œin nโ€u,ceeqes ,ihhwc orf het psrusope of eht eptS ,1 is waslya at het -.neNsimtru eTh sangli eequsenc ellst troeh stcyolico ,nespirot H!yeโ€œ Tkea me dn(a eht erst of hte etpiepd of cwhhi I am )tapr to eth RE!โ€

In eht baecnes fo hist ga,inls a opitenr lliw ranmie in sit lteโ€œudaโ€f hmoe of the tolcso.y

q&;sesrruHoe a icne emcsacthi soghwin het wfol fo oesnptir mrof ilintia yehsntiss ot filna aiind:tsseotn


dtoEnsen

  1. Teโ€œh isnhstyes of luyivatrl all noipsert ni hte ellc gsbein no ossmobier in het co.โ€yolts (seisEnalt elCl Blygioo, teAslbr et .,al 4,021 p. 92)4

*fI you elyral anwt uyro idmn wn,olb cisdnroe htat neve eht rotenpi bsutsinu atht maek up htat /31 of a seoobrim era vstmsehele taiyinill eenszisdyth ni eht oosl;ytc e,lrta tyeh ear opnasrertdt back otni hte ulnsuce iva teh curanle r.peo

qball  Awesome explanation. Now explain it to me like I'm 5. +8
drdoom  All baby peptides are born in the cytosol. But some baby peptides have a birthmark at their N-terminus. The birthmark tells a special mailman that this baby needs to be delivered somewhere else. If you chop off the birthmark โ€” or erase it somehow โ€” the mailman never knows to take baby to its true home. The end. Now go to sleep or Santa wonโ€™t bring your presents. +36
... niboonsh made a comment on nbme21/block4/q#45 (During an experiment, an investigator observes that...)
 +45 
submitted by niboonsh(336)
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vac/-hHytueopt4wtov2hQms.u=bww/.Dw?w:c/touz fi ru yalz leki e,m htis si a good eesferrhr edvio

d_holles  Amazing video dude. Somehow never learned this in neuro lol. +6
aag  Awesome video! Is this why you can give Mg2+ to eclampsia patients, because if so, mind goddamn blown. +1
... hayayah made a comment on nbme21/block3/q#33 (Left radial arterial and venous blood samples are...)
 +40 
submitted by hayayah(1056)
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eth irmtayoj fo baoncr iixddeo sumeloelc rae ciedarr sa rapt of eth eibbaatnocr bffrue ym.tses In itsh sst,eym rncabo didxeio fufesisd oitn hte BR.sC ricaCbon rasnhaedy AC() hniitw BsRC kquycli rsonvcte eht nbrcao xdiieod itno icanrobc iacd C)3.H2O( Conrcbia ciad is an sbatlnue dtinreeaemti lmecueol htta alyidtemiem isstdcasoie into bnicoebaart nios O()C3-H nda noyrehgd ()H+ .oisn

ehT nweyl yssehiztend ebariaotnbc nio is rtporaesndt uto fo eth RCB toni eth spalam in eagenxhc fro a rdceiohl oni C)l;โˆ’( htis is dlacle the ihdrcole i.shtf nhWe the odlob seerach eht ,lsnug eth obacbartien oin si oetrdrsapnt kcba onit eth BRC ni eengxcah ofr eth elicrhod ino. hTe H+ noi csesdoiatis mofr het benoihgmol dna sdnib to hte icbntaabeor .nio hiTs rousdecp the ancicorb aicd mt,teaeriinde whhic is ednevtroc akcb ntoi nobarc diexiod hthorug het eyamczitn inacto of A.C eTh noacrb oiixded ucredodp si edxlplee hhrogtu eth nlsgu uindgr lihta.eonxa

hungrybox  Amazing explanation. Thank you!! +1
namira  in case anyone wants to visualize things... https://o.quizlet.com/V6hf-2fgWeaWYu1u23fryQ.png +5
ergogenic22  CO2 is carried in the blood is bound to hemoglobin, known as carbaminohemoglobin (HbCO2) (5%), dissolved CO2 (5%), bicarb is 90% +3
pg32  Nice explanation, but can anyone clarify how we know from the question that we are measuring HCO3 rather than dissolved CO2? +3
qball  @pg32 This question is asking about what accounts for the LARGER amount of co2 and the HCO3 buffer is about 85% of this transport and dissolved C02 is about 5-7%. https://courses.lumenlearning.com/wm-biology2/chapter/transport-of-carbon-dioxide-in-the-blood/ +3
teepot123  fa 19 pg 656 +1
... mcl made a comment on nbme21/block1/q#16 (A 43-year-old man comes to the physician for a...)
 +35 
submitted by mcl(578)
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eLdlbea RXC isnwogh oitipsno of eetdirfnf ea.vlvs

hyperfukus  this link is great! they're still kind of close together :( its so hard to tell for me w/o reference of the others +
hyperfukus  this link is great! they're still kind of close together :( its so hard to tell for me w/o reference of the others +
mannywillsee  So the way to differentiate Aortic valve from the others is by checking the lateral view, AV will be more medial than both tricuspid and mitral; tricuspid will be more anterior and mitral will be posterior while Pulmonary is doing its own thing +2
... notadoctor made a comment on nbme21/block1/q#32 (A 50-year-old man has had progressive dyspnea on...)
 +30 
submitted by notadoctor(151)
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usaUl iiaentrtltis ntpuomsiine si het iathoollscig tidifneino of iIditochpa rmauloypn b.isfiros eW wnok htat ihts petatin ash lapyrmnou ssboiifr aubesec eth itosunqe ttssae that three is rouibsf nghcekiint of eth vaoerlal pe.ats iThs sietunqo wsa jtsu tnigtse atht ew wenk eth orhte esmna rfo amylunroP sr.iFoisb

aneurysmclip  Nbme back at it again +24
pg32  Is it still considered idiopathic pulmonary fibrosis is it appears to have been caused by an atypical pneumonia? +1
zevvyt  Why not Sarcoidosis? Wouldn't Sarcodosis also be a chronic inflamation with fibrous thickening? +2
swagcabana  UIP is a better answer. Sarcoid is a leap in logic, usual interstitial pneumonitis is textbook histological definition of idiopathic pulmonary fibrosis. The biopsy has no mention of noncaseating granulomas and the clinical picture is not consistent with an inflammatory process. You have to focus on the better answers, try not to get caught up in the "why nots?" Calling this sarcoidosis is like someone coming in with prototypical asthma and jumping to eosinophilic granulomatous with polyangiitis. Sure its a possibility but its definitely not likely. +6
mangotango  I picked โ€œdiffuse alveolar damageโ€ with Pulmonary Fibrosis in mind but these are actually key words for ARDS :/ +1
zevvyt  thank you swagcabana! Very good explanation and strategy! +
... hungrybox made a comment on nbme21/block3/q#15 (A 47-year-old man has jaundice. Laboratory findings...)
 +30 
submitted by hungrybox(963)
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why eyihlsosm is :owgnr

rheTe hlsduo salomt evern be trhiatgs pu bibiuinlr in het .iruen In sie,oshmly hte eexcss luibinrbi is eerdctex in eht .ible efArt ltrbaacei vnoorescni nad ,rpetekau osme illw be etdrecex in eht ineur as inl.oubir wev,eorH in cetsorubtiv sdd,eoirsr the udaotgejcn blinirbui iwll renev veah eht opnpytuoirt ot ounrgde lbaitecar nrooisvenc ot obrenusc.ol/tiir nI hsti ywa, eht dugntceajo bribniliu ahs no oterh ywa ot eb xtcrdeee roteh nath tcirelyd in het uneri.

eicsdtr ot aaun7/a3lr6c/ no iedtdr

skip_lesions  Found a good pic showing bilirubin metabolism +
... hungrybox made a comment on nbme21/block2/q#17 (Scientists have identified the flawed gene that...)
 +28 
submitted by hungrybox(963)
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enwh dffi sgieln tsarnd riaper ehsasnimmc era s:due

  • pareir ewynl eztisdyhens d:rstan hicsammt rreapi (cynhL oy)erdnsm
  • aierrp iieyinrmdp mdiesr adcseu yb tda UV reesoxp:u itedenuclo oxciesni repair odaXem(rre inogusmemp)t
  • piearr aei/ocusnpsxootnt :atraiteoln besa nioscixe pirare
meningitis  Brca: recombinant repair +
brotherimodu  P.40 FA2019 lists the different DNA repair mechanisms +2
teepot123  fa '19 pg 382/3 +
... jambo2222 made a comment on nbme21/block4/q#5 (An 11-year-old boy has had persistent pain in his...)
 +28 
submitted by jambo2222(28)
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Isโ€™t na omseaoa.rcsot ramScao = amhgostoeeun .mtse sโ€™It ni eht gesl so nthki hwo a DVT gseo to g.uln meSa eda.i

tinydoc  Perfect way to remember it. Thank you! +7
chandlerbas  Iused the mnemonic PB (lead) KeTtLe....looking at the stem it said "osteolytic mass" meaning that it has to be either Breast, Kidney, thyroid or lungs. none of the rest are options leaving lungs. but jambo2222 very noiice that works too! +1
jajajaja  @chandlerbas I think you might be using the mneumonic backwards- PB-KTL is for primary cancers that met to bone. For example, a primary lung cancer can met to bone and cause an osteolytic lesion. But in this case the primary cancer is the osteosarcoma. Meaning that the mneumonic doesn't actually apply to this question +13
chandlerbas  ya you're right good stuff!! I dont know why that made sense during the question...anyways to add to the other comments...osteosarcomas are aggressive and 10% metastasize to the lungs via hematogenously at the time of diagnosis. +
mtkilimanjaro  just to add, in terms of venous circulation everything goes to heart via vena cava and then to the lungs. The only way the bone would metastasize to these other structures would be if it continued through arterial circulation without seeding, which seems unlikely. The only ones that spread to the liver are from the PORTAL venous system, aka not bone only colon etc. +1
... hungrybox made a comment on nbme21/block1/q#49 (An 80-year-old woman comes to the emergency...)
 +27 
submitted by hungrybox(963)
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oclizhdoroediHhaytr si a ehiaiztd dtieuirc t;g&= hedizati iitedscru aer seidoastac iwht pheoilmaayk.

atWh orhte reisuditc are dstasoicae tihw ih?maepkoayl ooLp idruc.stie

yWh?

iIniinhobt fo Na+ iarrsnobetop uoscrc ni boht olop utericdis tnbhi(ii NCCK oprrnrt)otcase dna adzhieti itueisrdc tbihi(in CNla r)rntcrsarpotoe. All of sith arsceneid N+a ieeasnscr toAnolsdere aiiyv.tct

eaenRltv to hist pomeb,rl otedArosnle gueeslptaru seposnerxi of teh N+a/K+ APT otiterparn sb(robera +aN toni ,odyb peexl +K noti l.men)u ihsT tesrslu ni ioykmlaaphe in eht yd.ob

Hnga on, 'ehetsr reom hgih ielyd iof!n

oonrlAetdes deos eon thero rttnipmao hnigt - ivticaonat fo a H+ anncleh tath eplxes H+ oint eth n.lmeu

S,o igven ttah tsih pntitae ahs ,kaholeiapmy uoy owkn there si lpoirneuutga of .eAosrdtelno Do uyo tnhik rhe pH uodwl be hih,g ro wol? lcaE,yxt ti wdoul be hihg eesuacb cn.i ondoltserAe g&;t= nc.i +H leelxdep iton hte ulnme ;=tg& ciobmtale iasa.oksl

owN yuo ndrdntuase hwy htob polo uciisdtre and ezhitdia stuiidrec cna ceusa as'hwt dlealc l"ocyaheipmk tmeclobia sklalia.o"s

hungrybox  jesus this answer was probably too long i'm sorry +7
meningitis  I disagree. It's the complete thought process needed for many Thiazide/Loop question that can be thrown. Thanks. +12
amirmullick3  This is what NBME should be providing with each question's correct answer! Thanks hungrybox! +
amirmullick3  @hungrybox did you mean "All of this DECREASED Na increases aldosterone activity."? +1
pg32  Anyone care to explain why she feels she has, "lost [her] pep"? Is that due to the hypokalemia? Or hypercalcemia caused by the thiazides? +
cmun777  @madojo @pg32 I assumed between her hypokalemia (which can cause weakness/fatigue) and possible contraction alkalosis those were the most likely causes for the "lost her pep" comment. I think if they wanted to indicate hypercalcemia to differentiate if loop diuretics were also in the answer choices they would certainly give more context for hypercalcemia sx +
... acanthosisnegrocans made a comment on nbme21/block2/q#40 (Acetaminophen and nonsteroidal antiinflammatory...)
 +26 
submitted by acanthosisnegrocans(26)
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In eht egrta wsodr fo Dr raSa:tt

laPnring"sdoat 2E eaidmtes vee"eeeeeeeefre

DISANs &;-tg- bcokl lndgtoaprnsia nsy

thisisfine   This is all I heard in my head +7
temmy  Me it was so weird +
peridot  I do want to add, that while PGE2 is the right answer, FA19 p.213 says that IL-1 and TNF are involved as well. However, because the question asks about what is going on in the hypothalamus, the answer is PGE2. If the question had been asking about what the macrophages were releasing to influence the hypothalamus, then the answer would have been IL-1 or TNF (FA didn't specify if it was TNF-a though...). +1
feeeeeever  You know why I'm here +5
... madojo made a comment on nbme21/block1/q#39 (A 33-year-old woman comes to the physician because...)
 +24 
submitted by madojo(157)

Know your STD's baby ;-) (going through every other choice on this question):

  • Bacterial vaginosis caused by gardnerella vaginallis. Se a thin, off white discharge and fishy smell (fish in the garden). There's no inflammation Lab findings: pH greater than 4.5 (just like trichomoniasis), and a positive whiff test with KOH. Stem will say something about malodorous discharge and show the infamous CLUE CELLS if we are lucky. Not the answer for this question obviously because we would not expect vesicles with this bacterial disease.

  • Candidiasis is going to be your thick cottage cheese discharge, with inflammation. normal pH see pseudohyphae. Treat with topical nystatin, or oral fluconazole unless you're pregnant than use Clotrimazole. Again not going to see any vesicles.

  • Chancroid per uworld is associated with Haemophilus ducreyi you will have a Deep purulent painful ulcer with suppurative lymphadenitis. Will be told that patient has painful inguinal nodes, there may be multiple deep ulcers with gray-yellow exudate. You do cry with H. duCRYi This wouldn't be true for what our patient has in this question because we aren't told of any inguinal adenopathy. a link to a chancroid VDA

  • Chlamydia trachomatis causes lymphogranuloma venereum which is small shallow ulcers, painless, but then the large painful coalesced inguinal lymph nodes aka BUBOES. Compared with gonnorhea the discharge is more thinner and watery. Again not the case here as its painful and no mention of any BUBOOESS. The discharge in gonorrhea is more thicker. Both lead to PID, treat for both because confection is common. With both patient may have some sort of pain or burning sensation upon urination. Sterile pyuria though for both.

  • Condyloma accuminatum is a manifestation of HPV 6 + 11 (genital warts). They look like big cauliflowers. This is in contrast to Condyloma lata that you see in syphillis which is just a flatter latte brown looking macule.

  • Genital Herpes (the answer to the question) will present with multiple painful superficial vesicles or ulcerations with constitutional symptoms (fever, malaise) Just fits better than all the other choices I ran through.

  • Syphillis is the painless chancre. UW describes it as a single, indurated well circumscribed ulcer, with a clean base. See corkscrew organisms on DF microscopy. Keep in mind other painless ulcers are lymphogranuloma venereum of clamydia (but the buboes are whats painful not the ulcer), and granuloma inguinale (donovanosis - klebsiella granulomatis) but whats hallmark about this one is that its painless without lymphadenopathy

In short, be safe.

drdoom  this write-up is AWESOME ... but it also made me vomit. +
b1ackcoffee  This is awesome, writeup, not the stds. +
lovebug  FA 2019 pg 184. I summed up @madojo's comment! this patient have "multiple, tender vesicles and ulcer". and scant vaginal discharge. A) Bacterial vaginosis -> NO vesicle -> r/o B) Candidiasis -> NO vesicle -> r/o C) Chancroid -> should have Inguinal Adenopathy -> r/o D) C. trachomatis -> have Large painful inguinal LN -> r/o E) Condyloma acuminata -> Big Cauliflower -> r/o F) Gental herpes -> YES!!! G) Gonorrhea -> NO Vesicle, creamy prulent discharge -> r/o H) C. trachomatis again (same as D) -> r/o I) Syphilis -> painless chancre -> r/o J) Trichomoniasis -> strawberry cervix, motile in wet prep -> r/o thanks @madojo! +
... sympathetikey made a comment on nbme21/block3/q#4 (A clinical trial is conducted to compare the...)
 +24 
submitted by sympathetikey(1248)
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โ€ข rPe Poltoroc - nylO ilcednu tpenasit in het eusstrl ohw loloefdw the roptloco

โ€ข sA edatert - taaD wsei, oynl treta teh tuesscbj sa teyh eerw rtaedet ex( - fi rexealpmtnei taentip oesd athw eht loconrt paintset are pepduoss ot ,od vmeo htat eexrntalpeim atnteip to het crotlon pruog

โ€ข Ientnnito to atrte - dInlceu lla setpiant in hte sorupg yeth reew liogylarni nmiddaeorz ot

... assoplasty made a comment on nbme21/block2/q#29 (A healthy 25-year-old man is participating in a...)
 +23 
submitted by assoplasty(92)
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tsaF era ekgnietoc cxe(tpe odd nicah A)F, os tyeh udpreoc ksoente fro nreyge cruoitdonp lAoc(-)eCtAy retarh htna su.clgoe fI eht uoniestq kaeds awht eht rmyipar rcosue fo nygeer oorpnuitdc wa,s it olwud stlli eb eocyggnl n(da ton )oen,eskt ucaseeb sthi si tiwhni 42 oh.rus vowreeH arfte 42 ourhs the resnwa odcul eb tnkeeo d.sbeoi age,rdlseRs hte tsiouqne flilspcaycie sadi the tp dha a erusm cuselog of ,100 tiaicindgn htat ew rea ioonkgl fro gtmniesoh hatt evsiordp a esuasttrb fro osoeseieclngnu.g

During soeprid of r,avstaniot tsuarstseb for gleossonnecuegi cmoe ofmr two rc:esosu 1() ndarkeobw of gnxeiist s,cleum or )(2 avi coddniah- AF thguhor r.po-ionolAyCp Vai*len( slao edsfe iton pypnrloio AC,o ubt is otn einvldov dgrnui nvatiosatr &;-t-g ees lbwoe)

(1) eTh raypianvun-aeetl ycecl rodpisve hits iuntmgela( in ulscme + ureavtpy &-;-gt aialnne t-g&-; gsoe to erivl -t;g-& rtasioinmaannt ot arollopu-etetgathka t;--g& rvtueapy is apdraeset rfmo timlenagu &t-g;- alguenimt sego ot auer elc,cy ryutavpe esgo on ot e.lneisgsenc)goou cattLea can alos eb sedu h(tsi dlouc eahv eenb a irgth nsrawe fi ti ewer d.esi)tl

)(2 ddO hicna AsF rea osal cguonegli,c utb sictrea cida o(didepvr in the wensar h)eocci nsitโ€™ odd hnc,ia os it si nloy tgniekcoe nad cna be uredl o.tu

oglhthuA navlie da(n rtohe ehandcrb .a.a) fdee tnio lP,yopoCi-Aron hyte are tno esdu in tsarnviato sbuaeec aittaonvsr ctslrtyi esleri no etiphca o.cesongsnuigele eTesh aa.. aer nto bledeztamio ni hte lveir acseebu eth virel lskca cn-indhhcaerab .aa. eaersnrtfsa zee.mny In sFtir ,Aid eimhcBo sncot,ie duern gi/tsvoSraFta,tnian ni ohbt teh ifantgโ€œs satetโ€ hhicw( is iiwhtn het etmi aremf fo tsih tu),snqeoi or teh stโ€œinorvtaa t,โ€atse both eliuitz cihpeta seneiocngo.glsue My painstmsuo si hatt vnelai si deus dgirun elgurra bml,msoitae and not gdrniu esdiorp of natr.oivast

hello  I want to re-emphasize something that @assoplasty has already stated :). The Q-stem states serum glucose = 100, and the Q asks why the patient is able to maintain normoglycemia. Therefore, you can immediately eliminate choices A and C because acetoacetate and beta-hydroxybutyrate are sources of energy during ketogenesis -- ketogenesis does not provide glucose energy sources. +7
chandlerbas  ^ this checks out: valine and isoleucine are broken down in the muscle into branched chain 2 oxo acid via branched chain aminotransferase (reversible) then the valine and isoleucine leave the muscle and swims to the liver to be acted on by branched chain 2 oxo acid DH (irreversible). So bascially the process from taking BCAA valine and isoleucine requires 2 enzymes. the first enzyme is in the muscle, and the second enzyme is in the liver (for simplification purposes --> both organs contain both enzymes but dont have the same affinity for their substrate). source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1147506/?page=4 so you're right to say that the liver +4
toxoplasmabartonella  Thank you for such a great explanation. Isn't it glutamate instead of glutamine that combines with pyruvate in muscle to yield alanine for Cahill cycle? +1
almondbreeze  @ toxoplasmabartonella think you are right +
... cantaloupe5 made a comment on nbme21/block1/q#3 (An investigator is studying the efficacy of distinct...)
 +22 
submitted by cantaloupe5(72)
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uplsaaCr sdiocycharepal inaccvse are netof gutodncaej to snrptoei ot mievpor .unoignmcytiemi langFilel si teh lnoy ranwes eocihc sttah' a ei.rpton

mambaforstep  both MHC 1 and 2 are present antigens that are PROTEINS (FA 2019 pg 100). so in order to elicit a T cell response, you need a protein (CANT BE A POLYSACC). that is why vaccines for polysaccaride antigens are often conjugated to PROTEINs--> so that we can elicit a T-cell response (FA 2019 pg 127). +5
lovebug  Flagellum = Protein, (FA19, pg.124) +
... usmleuser007 made a comment on nbme21/block1/q#17 (A 7-year-old girl is brought to a clinic in a...)
 +22 
submitted by usmleuser007(370)
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fI yuo tncduo'l memerebr cihwh rwee nt;sialees neth vnlaireeatt udwol avhe bene to laerize ttah ngoriwg inhedlcr ndee esllc to vd.edii siTh ueresqir NDA naretcoiipl nad .trinoatslna Of hwich eht cunleci dcia ethyim si otrmipt.na tI rerieuqs a hmytel ant.rsref

Tshi si erhwe imoehneint moesc .in ieMohnnite meosnicb with TAP to ormf MSA (a emthly o)dnro

whossayin  Thatโ€™s a legendary explanation. Thanks dude! +
makinallkindzofgainz  This is exactly how I solved it! I remembered that Methionine is essential for methyl transfers, and you would need that in dividing (growing) cells. But now I'll just remember PVT TIM HaLL too :) +2
... flashvoyger made a comment on nbme21/block4/q#25 (An 80-year-old woman cannot concentrate her urine...)
 +22 
submitted by flashvoyger(22)
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Teh sqeonitu si iknasg oyu owh hcmu rawte utsm eht noamw aekt in ot iiatnnam the emsa tlyims.loao shTi nmowa teaks ni 405 sOmm of sulote rep y.da shiT is a unti fo nueermtesam -- ktnih fo ti like m.sarg

rFo her ot epke teh ames ylaoiomslt ehs umst xreecet 045 Osmm rep da.y eTh olny awy rfo rhe to ereextc eth lsoteu is vai hte .sdineky heT nylo wya for rhe ikesnyd ot eerxcte 054 Omsm si fi yhte xteerce 1 treil of arwte .salo sihT si eht axm iacotntonenrc ttah hre iyndeks acn d.curpoe e(rH sdnykei are nto oโ€œpeulrfw ugeoโ€nh ot ekam rhe eruin ayn rmoe tcacntrnedeo tnha ahtt).

Thsi mwona si sola nsglio hoerant itlre fo rewta to efse,c gsetawni dna .oeipnatirsr ihsT is hte isnbeโ€œielsn arewt .losโ€s Tath msena fi she sniogl 1 tirel fo ewrta to ,saetw aorsretiinp nda seecf per ady upls 1 rteil of eratw ot erinu sa(eecub ehs sdeen to sveisdol rhe uoelts ni s!m,ihg)tneo fro ehr dlboo to saty eht mesa ylls,toaimo esh sutm elecrap het artew hes tlos sthu ,usmt ta mmniui,m nrikd 2 riselt of treaw per y.ad

jean_young2019  great explanation๏ผThank you๏ผ +
... taway made a comment on nbme21/block2/q#14 (A 30-year-old woman comes to the office because she...)
 +21 
submitted by taway(29)
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Tihs neqiotus si ershadp ,lgsyterna tbu st'i sisyleneatl naiksg "tahw uldwo hppane if shit ws'noam imrodtyhohipsy ebemca crnoutolndel rove eht scuore fo rhe yp"gn?cnrea

lrtruecyn erh THS si oogd -gt;&- ltleonwldreoc-l roAyEmTtpOyHhYdToHIPhL Csii hhgi HTS ;tg&-- rhe iyhysiromothpd tums OTN be wteocllolndr-le ued( ot oputsniird of eht STTHH//3TR/4T neoenirdc a)xsi

So, wno atth ew ernnuddats that teh tqnousie si kaisgn a"twh odluw phepna if erh ihpydoysmrthoi asw tnulr?ed"cnool

:wnAesr cnmisetri

I ktnhi atth tish etuionqs is rdhspea uostryilcoa, utb rfa eb it mfro em to eciritzic hte EMUSL cnnesgili .ar.b.od

yotsubato  I think that this question is phrased atrociously, Just like the rest of the NBME +17
b1ackcoffee  exactly how does maternal hashimoto can cause cretinism? +
notyasupreme  @b1ackcoffee, it's not maternal hashimoto, basically you just have to disregard the ENTIRE question stem and the last part of the sentence (if the mom's TSH goes up) means that there's hypothyroidism going on, which causes cretinism. +1
b1ackcoffee  Thanks you @notyasupreme! +
... g.liller@yahoo.com made a comment on nbme21/block3/q#5 (A 70-year-old woman is found to have persistent...)
 +21 
submitted by g.liller@yahoo.com(27)
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aandCid si a rpat fo hte amnlor alofr of n,ski doclu sceua tnamniconoita fo a anlecrt uosnve etce.htar heT nutsioqe seatst atht eht sramoing si l,rpeup d,inbdug ddi tno ropsned ot odrba ercputsm istnoactiib (aak eyth itnd'd eus lazuonoelfc ro piicorahtenm .B) L,ltsay tehy hwdsoe ti dpleat no oldbo aagr adn rtehe wsa no sylehismo hchiw emetnailsi tpsah teh( lnyo etrho opbesisl tenndocer e.h)er

orpsycCccout lyualus isvnoevl esimtningi in sopnocodmrmmuemii ps.t . E coli si ramg enosvxtthgaeropi ri is uayulsl ertastinmdt yb a hntro no a orse or nemsoeo hitw a tohyisr fo dgernngia

hungrybox  Also, the yeast form of Candida is gram (+) +23
dr_jan_itor  I got thrown off by the part where they said "ovoid" and thought they were implying a cigar shape. I chose sporothrix for the morphology in spite of knowing that it clincally made no sense. +1
lilmonkey  I chose S. aureus before reading the question (looks like b-hemolysis). Then I saw "budding organisms" and picked the correct one. +
the_enigma28  I think, elliptical budding yeast forms kind of excluded cryptococcus since its almost round -_- +
the_enigma28  I think, elliptical budding yeast forms kind of excluded cryptococcus since its almost round -_- +
lowyield  cryptococcus also doesn't take up gram stain because the shell is too thiqq +2
... henoch280 made a comment on nbme21/block4/q#15 (A 5-year-old boy is brought to the physician for a...)
 +21 
submitted by henoch280(50)
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@etmmy. hisT ousqntei sstte rou lokedngwe on biaisnml cihwh is lnrlymoa a osytenrisa ifyiedcenc dasesie utb hte vtnteegi tsteas that hte osby' iiabsmln si cuseda by a geentic uittamno ni teh YRT1P nege hcwhi is wnsho in teh bicmioechla atwy.hap A ngee that splhe ni hte ssynsehit of n.Eulineam

owN oyu haev to auntednsdr ahtt lal uerrcsrpos eoebrf htat neeg is het ytpahaw woudl iltsl be aeaviblal fi not eeasnrdic hicwh akme 2 of hte nipotos ni hte intusqeo or.gwn

uoy sola ehva to tarnnesudd mni(n)iteE as:ulh = il(mnomanore)n .ei nlmaor anlmein hhcwi is ertcoipevt ot eth ksin, adercsese raetcvei gxeyno eecsisp dan egvis the radk sgipmetn to het siir, ocr,ihdo ksni, raih oneeeme fhaiw. t).n(icl.l = fkne)(nmlaeai ei. ihnn,lpoeame teh neo epsnrte in uro iettpan rhee hwhic is ssel pvitertceo niaag the vu a,syr cnotna tgmepin adn tncnoa edrscaee RSO nrdetgaee ni the ni.sik peho ihst splhe

... pparalpha made a comment on nbme21/block1/q#35 (A 7-year-old boy is brought to the physician by his...)
 +20 
submitted by pparalpha(83)
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Lead ioyxtTci :

aesC:su ordiupints of eehm seshytsin iav nbtionihii fo ALA vulilnoentam(iae yead)rsdetha

i:Fnsingd

A: eAmnia

B: oipBslaich lpgptsini

C: olciC

D: Daerhria

E: onaElcpetapyhh

F: toFo prdo

G: umG /ogdsphrottweis geatru/ornatotid

H: NHT nda reeiepyhcaumr

retOh sreasnw:

iZnc incediecyf:

se:suaC owl kn,tiae 'nhosrC aseesid

isi:dngnF ummeni y,coiutfndsn deirmiap nudow lahgein r(of eht eemdoglirn shpae fo woudn ,liaegnh cinz is eedend by ameoesriotltpesanl to arkeb ndwo yept III l),lgeoanc ydoogpans,mhi earadihr, dtmitiaer,s iopc,leaa maranblo tseat nda emlls

cssExe is r.r.ea. ubt anc laed to dv//n nda dinoalamb pina

engasiuMm fdceyeinic:

C:saues ,tcnilganeo p,lyrauoi tn,larnimtiuo eviaxlta euabs

idnsFni:g ,tnaeyt umaetprer auvcnlrreit octnari,ntco eneiardcs QT inertlav

21B dcyfiecnei:

a:eCssu anegv ei,td ucoenpsiir aiea,mn pacarcntie us,eiss sgtacri sabyps ugrr,esy psltbanoairom Cn,h(or respu,) oolibrtmhlpuDiyh uloprctawmate/m iontinfce

Fi:sndign icmyac,rtco eolitclamagbs im,naae uneor to,pymsms rsaecndie eenyotcmoihs nad MAM lelevs in usmre

eeaIrscdn antVmii D:

:sesauC utaoongmaurls eeaisds cdr)aois(ssoi

i:Fdsnngi ebon e,nrrtopios too mhcu ic,umlca loss fo pitee,pta tsropu

lovebug  2019 FA, pg 411. +
lovebug  Nephrotoxicity results from lead exposure because the kidney is the main route by which lead is eliminated. Lead is absorbed by the proximal tubular cells of the renal tubules, where it binds to specific lead-binding proteins. +
... hungrybox made a comment on nbme21/block3/q#3 (A 55-year-old African American man with hypertension...)
 +20 
submitted by hungrybox(963)
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heT 2 eonncmmtdmas of tecsih :nuqsoiets

  1. tDo'n erve kcpi an sanewr weerh yuo suodn liek a dkic
  2. Dn'to reev nsutcol teh hcesti teeomtmic

vedrSe me llew on ihst .sueqtoni

linwanrun1357  If there is a choice about asking what the patient is worried about. Is this right? It does not sound like a dick :) +1
champagnesupernova3  If this were about a treatment asking why hes worried would be right but hes kind of doing the hospital a favor so I dont think you're supposed to try to convince or pressure him +1
brasel  also, any patient participating in any research study can withdraw whenever they want. Answer E is wrong because he shouldn't have to go through hoops to quit, he can just drop out at any time. +1
... drdoom made a comment on nbme21/block3/q#21 (A screening program is instituted for detection of...)
 +20 
submitted by drdoom(804)
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2050, sudttens ... but oyu dfni tou ndugir ruoy nltaiii esrcen ahtt 050 rlaadey evah eht esesia.d So, itsoerukt oehst .loeepp athT elevsa ,0020 tunedsst owh odtnโ€™ vaeh het sdis.eae

verO het oceusr of 1 ,erya oyu croesdvi 002 tudsetsn olededpve eth i.nfietcno ush:T

020 new sscae / 2,000 epelop who idntdโ€™ hvae teh esseida nweh yuo ttraesd oyru ysdut = 01 nprtcee

,kTciyr ykitcr MNEB ...

sympathetikey  Ah, I see. Thank you! +
niboonsh  Im mad at how simple this question actually is +7
sahusema  Incidence is measured from those AT RISK. People with the disease are not considered to be at risk. So 2500 - 500 = 2000 people at-risk. Of those 2000, within one year 200 develop the disease. So 200/2000 of the at-risk population develop the disease. 20/2000 = 10% = incidence +3
daddyusmle  fuck im retarded +2
... usmleuser007 made a comment on nbme21/block4/q#43 (A 4-year-old boy falls and lacerates his lower leg...)
 +20 
submitted by usmleuser007(370)
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  1. Htisslobesadoย om( tiogc)ntl: Wthini eth fstir efw untmesi of nirj,uy
    1. petinย tlslae the oldob gebin ot cktis to eht uijdner te.si
    2. iTsh ictvaetsa hte teltsape,l icnugsa a fwe tnihgs ot hapn.pe
    3. yhTe ecanhg onit an sourohmpa hep,sa roem elubstai rfo icg,tntlo dna tyhe areesle miccaleh glnssia ot mptoero l.gtnoict
    4. This rstuesl ni teh nottcvaiai ย fi,ionbfr whhci mrfso a smhe dan tsca sa "ule"g to dinb elpttsael ot chae rtho.e
    5. ihsT meksa aalttcย hotย  veessr to plug eth karbe in eth odblo ssle,ev igo/rvswptennlenig rfuhert d].gn[6eile][5b

  2. atlnminamf:oI igDrun stih ,shpae daedagm dan dade csell rae ldeacer ,tou alngo iwht reiactba adn rothe hpnsetgao ro srieb.d
    1. iTsh ppsaneh tuohrgh the srecsop ytpoigacย os,hsfo erwhe hiwet doblo eclsl e"t"a esibdr by nnuefilgg ย .ti
    2. vaded-lelPieettr whorgt rearatย cfos daselree tino eth onudw ttah ucesa teh mtgioniar and niiosvid fo eslcl gunrid teh apifvrreitleo epsa.h

  3. nlrPieiaotfro wgtho(r fo enw es)stui: In tish oenlnpย giodsiep,tsaloshuย ortย ย ogacasiagglne,ne,nnieia ife,otatย umonisrs zanititlhlpaei,eoi dan noudw rcncotitona r.oucc
    1. nI gena,eoissgni caasrvul tedianolelh leslc mrfo wen obodl sv.lsese
    2. nI srfolpabiai nad nialnuaogrt sitsue olifsmaatย w,rorrgoibfnostbย  nda mrof a n,ew aoeviatarrxpย olllrsnuecil t)mCxEi(aย Mr by xtceeinrg gloelanc ifenoci.bnย atrnd
    3. eultCoynrrc,n izio-itelraitelenhpa of the desmrpeii sccoru, in tiiwpehlcaleย hih ย plocefetlsrleari dan r'lac'w aotp het wound de,b iinrdvpog ovrec rfo eht wne ssiet.u
    4. In woudn isyortecalonocfne,mbย ย irstdtbaesocar het isez of teh donwu yb ginppgri het wondu geeds dna tnagcctnrio gisun a hcaisnmme tath mesrelesb tath ni ohmots selmcu elcl.s
    5. ehnW het sclle' srelo era eolsc ot ,coeteplm ndneedue lscle poeriodnssa.ย optgu
  4. naitratMuo eil():merngdo gruDni ratmanotui and l,eoirdngme

    1. olcgalne is dairnegle onalg otnensi isl,ne and scell tath rae no egrnol nedede era vredmeo yb dregmpmoar llec tdea,h sotaoippย or.s

  5. Aeprixomtpa tesmi fo the rftendfie sepsah fo nowud 1n,thwiagย ih]e[0l ddefa valenitsr mankrig blststnuaai rv,iaoniat dgeiedpnn amnlyi no nowud isez adn agnheli tcinsdonio, tub igmea oesd tno ciudnel jmaro smminiertpa atht ohncesccraiย u ow.usnd
mumenrider4ever  Great explanation! FA 2020 pg. 216 describes the phases of wound healing +
... mcl made a comment on nbme21/block2/q#30 (A 44-year-old man comes to the physician because of...)
 +19 
submitted by mcl(578)
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shTi si a yrttpe gdoo ugrefi wnohsig eth ninoevsorc of aeremnmb dishohppispol to iciordacahn su/krneoieaicldte .cte

dklcoaeB fo XOC zemnye yb nboiurepf tlssuer in edaercsde nootrcdipu fo atsligsnaodrpn 2H dna 2,E hewil uaicnsg eth srrrsecupo ot bc"ak "pu caisrndee( ihcaricdnoa .ai)cd Thsi, ni ,untr susrlet ni deaiensrc ucdprooitn of urtoleseiken.

icedcoffeeislyfe  FA2020 pg 485 has a figure that is helpful! +1
... hayayah made a comment on nbme21/block2/q#50 (A 65-year-old woman comes to the emergency...)
 +19 
submitted by hayayah(1056)
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etrCthae nptel:acme

e0ena/ts1adc//gt.u6la4.ne0ygtkmj:/opsih0cmo/w0ppn8ste//p0o-e82

aeRllc thta eth lugn epax tdseexn bveoa teh stifr rib.

hungrybox  His expression is so blissful. U can tell they're shootin up some full u-opioid agonist codeine type of shit and not some shitty partial u-opioid agonist buprenorphine type of shit or some shit like loperamide that doesn't even act on the CNS +29
rerdwins  even better, if you recall that the esophagus is RETROperitoneal ( its in like half the answer choices). hence, to get to it you have to go WAAYYYYY deep ( like rick and morty smuggling shit). after that, the lung option makes the most sense. +11
hello  Also, pulmonary artery is way too far away to be damaged by internal jugular vein catherization. +
makinallkindzofgainz  @hungrybox my mans just slipped in 3 high yield facts within a joke +3
makinallkindzofgainz  @hayayah, I have an issue with that picture unless I'm missing something. In every other source I have, the internal jugular vein lies LATERAL to the common carotid artery. The picture you provided shows the internal jugular veins medial to the common carotid artery. +1
cmun777  Look at the other side... I think it must be the manipulation of turning the head to the opposite side that better exposes the jugular for catheterization purposes +
... beeip made a comment on nbme21/block3/q#4 (A clinical trial is conducted to compare the...)
 +19 
submitted by beeip(123)
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I thimg eb het ylon resonp no earht woh tog sthi neo owrgn, tub rlgdeer:ssa

"ITT isaaslyn eucslind vyeer teucjsb who is aoeirmzndd dirocgcna to idaormenzd neaetrtmt mst.gneisan It eisgnor niocnocaplmen, tpoorlco iti,oedsvna rtwial,ahdw nda yatginnh ahtt pphesan ratef o.r"mnoaizdnita1[]

yo  You're not. I also goofed. +19
seagull  https://www.youtube.com/watch?v=Kps3VzbykFQ This video is a pretty decent explination worth your time on the subject. +2
hungrybox  I got it right but I was only like 50% sure. So I appreciate it. +
teepot123  ^ same video above used when I analysed my form 20 q which I got incorrect at time, its very clear at explaining this, helping me get it correct on this form +
... hayayah made a comment on nbme21/block3/q#27 (A 55-year-old woman with a benign nodule in the left...)
 +19 
submitted by hayayah(1056)
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eTh toydrih is ppdlseiu htwi aerrltia odobl rofm eht rsrpeiou ohirtyd et,rary a nabhrc of het txlnraee ciatodr eytarr, dan eth orinfrie hyrtdio eayr,rt a bcrahn fo teh hvyirtcarlceo u.ktnr

... beeip made a comment on nbme21/block4/q#6 (A 55-year-old man comes to the physician because of...)
 +19 
submitted by beeip(123)
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sThi ash bnee a tohgu nocctep fro me to te,g btu I nthik m'I llifyna rehet:

hTe etms is dnrsiciebg yirrmap ndraeal nc,iifsuifnyce ro n'did.sosA

  • THAC is nbieg e-eudpdcvroro to talimuste eht dreaslna ot uorcedp lorc,oist ubt heyt ac'nt predons, heriet ued ot arpyoht or ndotricsute BT(, imtuone:mua D4R, .)cte
  • heT itsfr 13 ionam adisc of HCAT nca be acvedle to fomr M,Sฮฑ-H hwhic umalsetsit e,soelnyatmc agicnus ropangtpiymneithe
jotajota94  Good job! Also, cortisol is involved in maintaining blood pressure. which was decreased in the patient. +7
tinydoc  Decreased Na and increase K+ --- Hypoaldosteronisim Hypoglycemia, and hypotension --- Hypocortisolism so the adrenals arent working ---- adrenal Insufficiency the Hyperpigmentation comes from the increase ACTH as ACTH is from Proopiomelanocorticotropin. SO - increased ACTH also increases a -MSH ---> Hyper pigmentation. +10
hungrybox  thank u for this answer +
bilzcop  Ugh! I misread the question and chose ACTH :( +3
cienfuegos  @bilzcop: same +
cienfuegos  @bilzcop: let's never do it again, k? +1
maxillarythirdmolar  Why does this patient have elevated BUN and creatinine?? +2
lovebug  @ maxillaryhidmolar > I don't know exactly. but maybe.. Low hypo-adlo -> our body lose water -> hypo-volemia -> Decreased GFR -> Increased Cr,BUN. If I'm wrong. please correct me. +
... hungrybox made a comment on nbme21/block4/q#20 (A 7-month-old boy is brought to the physician 2 days...)
 +19 
submitted by hungrybox(963)
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sihT vdeio xaepinsl getainl ygloombery mltreyexe llew.

If oyu eftl yotlalt lots ilek me, watch the vdeoi isfrt at x2, hetn eckhc otu teh mtbtoo urgife no pg. 680 in AF 1.092

elnaRvet ot thsi ntieuo:qs

  1. SYR tsrneiop matslteui toedveemnpl of tteess
  2. hisT tp ash etesst =&tg; eh tmus hvae het SYR eneg no the Y roemosocmh
  3. FMI ddersgea hte uraiMnell ,cudt iwhhc oudlw twoereihs mcbeeo teh ialnntre elamfe iaaligetn
  4. ishT tp sah nnaelrit mfeael algeiaitn tg=;& dt'idn aekm hnoueg IMF

Quiz yeorfusl swaser(n in a tperseaa )sopt:

  1. siTh ats'enpti rddsiore cna be raectd akbc to hwich lces?l
  2. hsiT iattenp adh nlmroa iagt.neali fI isht atnpiet dah lsmlaer nlagiiate tnha arolm,n htat luwdo eb a cfdete ni hwat eye?znm
ergogenic22  I like to work backwards. 1) patient has normal testicles on histology, normal appearing penis this must mean a Y chromosome is present, as testis determining factor is on the y chromosome (see above post point #2). I.e. you can eliminate choice A and B. Theoretically, 47XY and 47XYY could also present with female genitalia due to lack of MIF, but normal 46XY is more common +11
... cantaloupe5 made a comment on nbme21/block4/q#25 (An 80-year-old woman cannot concentrate her urine...)
 +19 
submitted by cantaloupe5(72)
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hโ€™Ses ikgnitna 540 mmsO epr ady os hes neesd to ecxetre 540 Omms rpe yda ot inaiamnt rmiblueq.uii uYo cโ€™atn sujt eeextrc mmโ€™Oss by esesmehvtl -- yeth aveh ot eb vossedlid ni osme oanmut fo treaw.

tseโ€™L say you cxerete 540 mOms thwi 500 Lm of eatwr -- that asemn uory ydkesin rea gtractneonicn runei :to

054 msOm รท 500 Lm = 009 /smmOL

utB het uimmamx tsih lsdyโ€™a ekydsni can ctnaotrcene ueirn ot si 450 ,sLmOm/ os she sha to rctexee ermo waert to gte ti hatt luted.i hTat taonum of wraet is 1 L, beuaces 405 /mOm1s L = 405 OmL/ms.

woN โ€™seetrh gnintho tspgpoin hre rmfo eecgxrnti eht 405 smmOs in na vene erom deltui uerin -- ofr maxelpe fi hse nkdar na rxate L fo tware neo d,ya teh snkeydi dcolu teg idr fo taht xtrae L iwht eht smea namuot of 045 smOm yb ntdiuilg hte nerui ot 045 msOm รท 2 L = 225 smmOL/. utB het inoeqsut kass for hte uminmmi nuomta fo tware -- whihc si 1 L yb the nkiedys (+ 1 L mrof eth ehotr fustf rof a taolt of 2 )L.

... imgdoc made a comment on nbme21/block2/q#33 (A 68-year-old man comes to the physician because of...)
 +18 
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I tothghu otuab it klei sh:it iettanP si vnhgai ynscgpcoeih DE - tis lla ni hsi a,ehd iodlbi si rlanom nad untncolra ernciseot are nloa.rm

If ihs snTsteeeroto evlel asw owl - Ldbioi ds.eedacer f I hsi revnous ysetms (tamaaisctsppihcreeh/tmypt)ay saw gaeddam - anultoncr nreiteosc deasedecr.

eopH ihts e.hpls

sars  Idk about this. My thoughts: -libido is a product of testosterone and emotions (psychogenic) -tumescence is a product of pelvic splanchnics S2-S4 (parasympathetic) -patient's issues are 1 month old (aka recent) and his wife died 2 years ago & testosterone is normal (therefore libido normal) -patient can jack off, therefore penile stimulation reflex arc is intact and pelvic splanchnics are working (nocturnal tumescence normal) +2
... feronie made a comment on nbme21/block3/q#7 (A 65-year-old man comes to the physician because of...)
 +18 
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mohiycrtcOe = โ†“ steeootestrn ndtrucpooi = โ†“ TDH tg;&= prttasoe escll nerudog ipotoas.sp T(shi chiemsnma si imisral to gunis -aeusrc5ฮฑtde ocsbrlek to taert PB.H)

osAipospt is ataedcechrizr by DNA amogatifrentn y,kssn(pio heikosra,rrxy siry)loa.ksy

hungrybox  DNA fragmentation histopath: https://i.imgur.com/nxYW8vL.png Note that degradation in apoptosis is progressive. From pyknosis -> karyorrhexis -> karyolysis. Aka condensation -> fragmentation -> complete dissolution. +22
... hungrybox made a comment on nbme21/block3/q#20 (A 68-year-old woman has had a fever and shortness of...)
 +18 
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esom nwogr essrnaw:

ska*em snees /cb ybsetamllso ear sursporcre ot t,cuoenylsrag ihhwc ues MPO ot igfht off fnctieniso

temmy  Hungrybox aka life saver +1
hello  Thank you!!! +
bbr  ....uh yeah im pretty sure we just call em "Auer Rods" now. Appreciate the answer tho! +6
... cellgamesgojan made a comment on nbme21/block3/q#35 (A 63-year-old woman comes to the physician because...)
 +18 
submitted by cellgamesgojan(39)
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VA ilFatssu o-urter odblo frmo eth rlaaietr emysst ot teh nseovu ses,tym psb-snaygi het setleiArro = rsneIeca LP tg-&--; ESNICERA .VR All ni all = eIraecsn O.C

Adnrcigoc to roUW,ld het lrstaeroie era a orjma uesorc fo aeesirctns ... os nsagybisp teh tseliroera eslrust in a deaescre in ltaoT elhPireapr eRancstise ... sucgain na esnreaci in hte aert dna lovemu of dbool rntinrgeu to eht ra.teh I ma tyertp reus eterh is orem to the yoypslhgio bdehni iths, ubt I oeph hsit xalpnedie a liet.lt

big92  "Immediately following creation, arteriovenous fistula (AVF) is associated with an increase in cardiac output (CO), achieved predominantly through a reduction in systemic vascular resistance, increased myocardial contractility, and an increase in stroke volume (SV) and heart rate. Over the following week, circulating blood volume increases in conjunction with increases in atrial and brain natriuretic peptides. These alterations are associated with early increases in left ventricular (LV) filling pressure with the potential for resultant impact on atrial and ventricular chamber dimensions and function." (PMID: 25258554) There's also another study by Epstein from the 1950s looking at the effects of AVF's effect on CO in men (PMID: 13052718). Apparently, the increase in resting CO is a big problem because it can lead to high-output cardiac failure (LVH). +23
hungrybox  Jesus big92 you went in on the research lmao u must be MSTP +6
temmy  big92 you are right. that is why pagets disease pagets have high output cardiac failure because of the av shunts. +4
kevin  what is "increase PL" +2
... hayayah made a comment on nbme21/block4/q#23 (An investigator is studying the regulation of...)
 +18 
submitted by hayayah(1056)
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phLmy lowf erat si uusylla .lwo tI si fildeuencn iriylmarp by hte rate of ylpmh fnoramto.i For lxape,em fi oodbl alilarpcy peuerssr si nrseieacd by aaerilrt iodosvnialta ro nuoves tntnoic,csiro hte lfwo ater fo ylhmp snsaeec.ri ,Asol the wlof reta is fcfeadet by spomosiecrn fo yapilmtcsh by cnntciaotor fo gibregnnhoi mrtuuaelcus nad yb neivgtea itiacahrrntoc rurepsse na)ehg.b(itr

tinattsIreli epussrre (so peuerrss in the FC,E hchiw owlud ecarisen if vineg IV lai)nes dan yhmlp fwol ear ieiposltvy el.tared A alslm iacnrsee ni tritsneiltia emuovl ytargle seacnesir sti ,erresspu tnmiorpgo lhypm lwfo that scta to reosret hte ertliitsitan euovlm ot .ormlna

mreo on siht itoc:p .po4.bciswn/ktwn8iw4/htKo/s/3vh5:/mBlo..gbNn

linwanrun1357  Do not understand the breathing ๏ผˆchoice C and D๏ผ‰ breath in and out are different? +
khanhluong  I don't know if it's correct or not but how I approached C & D was that they both cause vasoconstriction in the arterioles (because this is the lung where hypoxia causes vasoconstriction), which decreases hydrostatic pressure through the capillaries and eventually decreases lymph flow. Maybe I completely got this question right for wrong reason, but I felt that it works with all of the answers. For F) I was thinking that it would cause increased capillary oncotic pressure which causes more fluid to go into the capillary than into the lymph vessels... Here's a picture: http://www.lymphedemablog.com/wp-content/uploads/2011/09/Lymphatics.gif +5
... seagull made a comment on nbme21/block4/q#40 (A study is conducted to assess the normal mean serum...)
 +18 
submitted by seagull(1391)
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nimxagiEn tniptae rmfo a ortolsugi ipimsle onksreB Basi which loduw skew teh noppltuoia eamn of ursem eura neoitgrn ywaa mofr hte true acuaecrt naem. he,nT laierez rcienpiso si etdnnedep no attilsaistc e"roP"w wihch is sndirceae adesb on the ezsi of hte nlouptoiap of teh dstyu. eesanrdic( srnpoieic = sainrceed asaicitlstt peor.)w heoeerT,fr an secrnaie in ilptoouapn of a iasedb rpguo hwti leda to acyanircuc htiw ghih oriscin.pe

forerofore  to add up, the urologist himself doesn't add or remove accuracy (since this is a blood test), what decreases the accuracy is the fact that in order to be sent to a urologist you probably are sick in the first place (selection bias), so your urea nitrogen is likely to be altered. +21
sharpscontainer  I thought of precision as more of a function of variance. Variance will decrease with a greater sample size. Had a hard time because I was thinking about those 4 darn targets (wouldn't 500 darts look more spread out than 10? but no, the variance will be better) that have been in my textbooks since 7th grade and for the first time I was asked a question about this concept only to discover that I didn't have it down as well as I assumed. +1
peridot  @sharpscontainer I feel you, I thought the exact same thing. Looked into it a bit and I think it has something to do with the way standard error or standard deviation or something like that is calculated, but I'm still confused and too tired to dig further. Also, wanted to mention that this NBME has a similar question but instead it's about the 95% confidence interval - maybe that'll help you understand the precision thing better since the 95% confidence interval narrows with a larger sample size? So it's kinda tied to precision? +
... drmantistoboggan4 made a comment on nbme21/block1/q#47 (A 26-year-old woman (III-2) comes to the physician...)
 +17 
submitted by drmantistoboggan4(17)
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tI dsia it saw tfaal ot melas ni troe,u nda the uqsnoite deaks ouabt veli ornb siofr.ngpf eiScn eht slema etanrโ€™ enigb nbor ni eht rstfi p,leca I asdi 5%0 sefamle dna %0 esal.m

hungrybox  fuck i got baited +30
jcrll  "live-born offspring" โ† baited +21
sympathetikey  Same :/ +
arkmoses  smh +
niboonsh  why is it 50% females tho? +2
imgdoc  felt like an idiot after i figured out why i got this wrong. +1
temmy  oh shit! +
suckitnbme  This isn't exactly right as males can still be born as evidenced by individuals III 6,9,11. This basically an x-linked recessive disease. A carrier mother can still pass her normal X chromosome to a son (50% chance). It's just that the other 50% chance of passing an affected X chromosome results in death of the fetus in utero. Thus all males actually born will not be affected. +2
makinallkindzofgainz  @suckitnbme, Correct, but if you're a live-born male, you 100% for sure do NOT have the disease, so the chance of a live-born male "being affected" is 0. +3
spow  @suckitnbme it's not X-linked recessive, otherwise every single son would be affected and therefore have died in utero. It's X-linked dominant +2
qball  Jail-baited +
... ergogenic22 made a comment on nbme21/block1/q#6 (A normal-appearing 17-year-old girl has never had a...)
 +16 
submitted by ergogenic22(300)
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mitncorah aegivnet = on abrr oeibsd = pseonr itwh YX oeengpyt or XO abceuse iaentmy ouy eahv ermo tnah neo X roehoocsmm yuo ahev a barr bdyo ircnotamh( vi)epstoi

... hayayah made a comment on nbme21/block1/q#11 (A 27-year-old primigravid woman at 34 weeks'...)
 +16 
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HLPLE o:edsnymr dy tleaHvleoessimE iLerv eLm nezoysw lestlte.aP

A aesatinnfimto of esveer ml.eeaispracp ooBdl msera wsohs hicctsset.oys naC leda to IDC dan teichpa ma sraotbeuasulcmahps ยŽ uterurp ยŽ sevree enspn.tyooih

mambaforstep  FA 2019 pg 629 +2
qball  One thing I find odd with this question is HELLP is a manifestation of severe preeclampsia but she has had an otherwise unremarkable pregnancy. Shouldn't she have hypertension/edema in regards to her pregnancy beforehand? +
demihesmisome  Pre-eclampsia, if not severe, can be entirely asymptomatic. +1
misterdoctor69  Her blood pressure is 164/102, which qualifies her as having preeclampsia. +
... step1soon made a comment on nbme21/block1/q#16 (A 43-year-old man comes to the physician for a...)
 +16 
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ap-e.gmhsytoddylelss//iruc/taeo:aoa/krhv-aviltre

Lkoo at eehwr eht pscus era ipginont โ†’ rwudaps rrfhteeeo o.iacrt fi sspuc ewre orwnwdad โ†’ nhet tlarim velav uolwd eb hte htrig answre

misterdoctor69  mitral valve would only have 2 cusps even if it were replaced though right?... +
bbr  After staring at this for awhile, I wanted to elaborate on this to make it even clearer. The 3 areas that meet at a point would be the 3 cusps. These 3 flaps are going to get blown open. Means flow is from down to up. +3
... nicnac20 made a comment on nbme21/block1/q#28 (A 47-year-old man is brought to the emergency...)
 +16 
submitted by nicnac20(18)
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eMdxi sunveo yxengo sieontn is het uotnma fo xeygon nudbo ot biehglonom as ti rtresun to hte rgith iesd of teh tahre eftar eniarlvtg to eht ses.utis

esDeradce yenoxg eyldierv ot teh ussetsi eud to aeedescdr dacarci tutuop ldeas to the ssistue xreiatgctn omre ngyoex ofmr teh spgaisn sBRC nath htye rmaynlol l,uwdo chihw seeecrads eth aervllo mdiex osnveu noeyxg neons.ti

pparalpha  A helpful equation is CO=rate of O2 consumption/(arterial O2 content-venous O2 content): Fick principle If CO is decreased, then the difference between arterial O2 content and venous O2 content is increased +15
misterdoctor69  To clarify a little bit, the tissues wouldn't necessarily extract MORE oxygen from the passing RBCs than they normally would. They would extract the same amount as they normally would to carry out their own functions. However, because the starting amount of O2 delivered to tissues is lower, you'd end up with less O2 bound to hemoglobin returning to the right heart. +5
... hayayah made a comment on nbme21/block2/q#29 (A healthy 25-year-old man is participating in a...)
 +16 
submitted by hayayah(1056)
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.P 91 of AF sah a ukqci lntanaeipox orf !hist

laaslBicy ocne reu'yo ni a nsiatgrv aestt r'stehe tisll cephiat nocesesiougelng ioggn on (as well sa sgiun AFF) tub eht iegusleoncsoeng is nmcigo mofr eraehrlppi susite atalcte nda annalie.

... dr_jan_itor made a comment on nbme21/block2/q#34 (A 28-year-old man is brought to the emergency...)
 +16 
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Otopni A is eht loyn nipoot werhe othb lmcsues era tpar fo the atbirlo fos.ol roA,l eht tlsa cenntese ni the utqoines etms si a oltat fdyierom fo hawt eon dlwou tcxepe het oinqsuet to be i.skagn It is not kigsan orf you ot saemsu that teesh msecsul veha eneb servd,ee yazlepda,r or eneredrd lfid.ca It si kansig ouy to asusem atht ehty evha emebco p"perdaetn" fi hte umlsec is naepptrde, thne ti anoctn olwal the yee to mveo tnio vwerahte istonpoi ti udowl eb in henw the sulmce is at its hgnenetled too.inpis So in isth c,aes It is teh nefiriro rutsce iegbn ernpeapdt ni a uliacnolynft edtershno ioosintp that is veneigtpnr wdupra a.egz

nutmeg_liver  @cjdinurdreamz it does make your eye look down, so since it's trapped in a functionally shorter position you're trapped looking down, not up. +2
... beeip made a comment on nbme21/block4/q#34 (A healthy 8-year-old boy is brought to the physician...)
 +16 
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"ryEcxtiaot onmia icad"s rsefre ot mleguaa,tt lwehi c"iBneoi"g pealnatyrp sfrree ot tyor,nesi teh rorpercsu AA ot daeimnpo nad eino.rp

sahusema  Amphetamines use the NE transporter (NET) to enter the presynaptic terminal, where they utilize the vesicular monoamine transporter (VMAT) to enter neurosecretory vesicles. This displaces NE from the vesicles. Once NE reaches a concentration threshold within the presynaptic terminal, the action of NET is reversed, and NE is expelled into the synaptic cleft +9
mumenrider4ever  FA 2020 pg. 239 +3
... nosancuck made a comment on nbme21/block1/q#17 (A 7-year-old girl is brought to a clinic in a...)
 +15 
submitted by nosancuck(85)
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Yo gwad ew lal about TVP MIT LHLa

ean,Pyneallihn ela,Vin TrDy,oKNApt neerniToh, esnciI,eulo eMh,noniite sti,eniidH eLcinue iseLyn

meningitis  I don't understand what the question is asking... can someone please explain it to me? Patient doesnt eat protein, shes chubby. What does methionine have to do with this? +2
charcot_bouchard  Just basically asking which is essential amino acids. +3
usmleuser007  Essential amino acids (something i came up with) 1. "Three HAL fans will try meth" a. Threonine = Three b. Histidine; Arginine; Lysine = HAL c. Phenylalanine = fans d. Valine; Isoleucine; Leucine = will e. Tryptophan = try f. Methionine = meth +3
nala_ula  They're saying there is a lack of good quality protein -> slight nutritional deficiency. She may have acquired weight but it's not because of protein. So they're specifically asking what amino acid she might be missing due to her subpar diet. Since essential amino acids are those that the body cannot make itself, out off those listed, methionine is the essential amino acid. It's on page 81 of FA 2019. +9
nala_ula  correct me if I'm wrong please :) +
hello  For anyone confused trying to follow @usmleuser007's comment -- slightly modified Essential amino acids mnemonic "Ah, Three fans will try meth" Ah = arginine, histidine Three = Threonine Fans (phans)= Phenylalanine Vil (Will -- German accent pronouncing English word 'will') = valine, isoleucine, leucine, lysine Try = tryptophan Meth = Methionine +1
pg32  Why does @hello and @usmleuser007 mnemonic contain arginine? That isn't in the PVT TIM HaLL mnemonic for essential amino acids... +
paperbackwriter  @pg32 arginine is semi-essential. It is essential in preterm infants who cannot synthesize it https://www.sciencedirect.com/science/article/pii/S0955286304000701?via%3Dihub +