Free Questions and Answers for All Medical Students all over the World
Q- A patient with atrial fibrillation is treated with dofetilide. Which electrophysiologic effect explains the antiarrhythmic action of this drug? A- Decreased phase 0 depolarization B- Increased refractory period by potassium channel blockade C- Inhibition of calcium influx in AV node D- Sodium channel blockade during depolarization Q- A patient treated with acetazolamide develops … Read more
Q- A 64-year-old man with a long history of smoking presents with hematuria. Cystoscopy reveals a papillary tumor arising from the bladder mucosa. Which molecular alteration is most commonly associated with low-grade papillary urothelial carcinoma? A- KRAS mutation B- FGFR3 mutation C- BRAF mutation D- APC mutation Q- A 14-year-old boy presents with a … Read more
Q- A patient with Parkinson’s disease is treated with selegiline. What is the primary mechanism of this drug? A- Inhibition of catechol-O-methyltransferase B- Inhibition of monoamine oxidase B C- Stimulation of dopamine receptors D- Stimulation of muscarinic receptors Q- A patient treated with verapamil develops constipation and bradycardia. What class of drug does verapamil … Read more
Q- A child has chronic diarrhea and failure to thrive. Stool is positive for fat. The sweat chloride test is elevated. Which mechanism explains the GI symptoms? A- Decreased pancreatic enzyme secretion B- Increased bile acid synthesis C- Increased gastric acid production D- Increased intestinal chloride secretion Q- A patient has progressive weakness and … Read more
Q- A patient treated with a nonselective beta blocker develops hypoglycemia that is difficult to recognize. What explains the masking of hypoglycemia symptoms? A- Alpha receptor blockade B- Beta-1 receptor stimulation C- Beta-2 receptor blockade D- Muscarinic receptor blockade Q- A patient with hyperlipidemia is treated with cholestyramine. What is the primary mechanism by … Read more
Q- A 27-year-old woman presents with a painless thyroid nodule. Biopsy shows tumor cells forming follicles but without the nuclear features of papillary carcinoma. Capsular invasion is present. What is the most likely diagnosis? A- Anaplastic thyroid carcinoma B- Follicular thyroid carcinoma C- Medullary thyroid carcinoma D- Papillary thyroid carcinoma Q- A 50-year-old man … Read more