Nokea
Sulfonamides are effective against:
- A. Bacteria and Chlamidia
- B. Actinomyces
- C. Protozoa
- D. All of the above
Correct Answer: D
Rationale: The correct answer is D. Sulfonamides inhibit folic acid synthesis, which is essential for the growth of bacteria, Chlamydia, Actinomyces, and some protozoa. This mechanism makes them effective against all the mentioned microorganisms. Choice A is incorrect because it does not include protozoa. Choice B is incorrect because sulfonamides are effective against Actinomyces. Choice C is incorrect because sulfonamides are not effective against all protozoa.
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Which of the following pairs of drugs were most likely administered to the patient with aortic dissection?
- A. Labetalol and prazosin
- B. Diazoxide and hydralazine
- C. Clonidine and captopril
- D. Nitroprusside and esmolol
Correct Answer: D
Rationale: The correct answer is D (Nitroprusside and esmolol) for aortic dissection. Nitroprusside is a vasodilator to reduce afterload and esmolol is a beta-blocker to control heart rate and blood pressure. This combination helps decrease shear stress on the aorta. A: Labetalol is a beta-blocker and prazosin is an alpha-blocker, not commonly used for aortic dissection. B: Diazoxide is a vasodilator and hydralazine is an arterial dilator, not the first-line in aortic dissection. C: Clonidine is a centrally acting alpha-agonist and captopril is an ACE inhibitor, not typically used in aortic dissection management.
The calcium channel blockers have direct negative inotropic effects because they reduce the inward movement of calcium during the action potential This consideration is:
- A. TRUE
- B. FALSE
- C. All
- D. None of the above
Correct Answer: A
Rationale: The correct answer is A: TRUE. Calcium channel blockers reduce the inward movement of calcium during the action potential in cardiac muscle cells, leading to a decrease in the intracellular calcium concentration. This results in a direct negative inotropic effect by reducing the force of contraction of the heart muscle. Choices B and D are incorrect because calcium channel blockers do indeed have direct negative inotropic effects. Choice C is incorrect as well because not all choices are correct; only choice A is accurate based on the mechanism of action of calcium channel blockers in cardiac muscle cells.
Dermatitis, diarrhoea and dementia are characteristics of:
- A. Dry beriberi
- B. Pyridoxine deficiency
- C. Scurvy
- D. Pellagra
Correct Answer: D
Rationale: Step-by-step rationale for why D (Pellagra) is correct:
1. Dermatitis: Pellagra is characterized by skin rashes due to niacin deficiency.
2. Diarrhoea: Niacin deficiency in Pellagra affects the digestive system, leading to diarrhea.
3. Dementia: Niacin deficiency affects the brain, causing neurological symptoms like dementia.
Summary of why other choices are incorrect:
A: Dry beriberi is caused by thiamine (B1) deficiency, not niacin.
B: Pyridoxine deficiency (vitamin B6) does not typically present with dermatitis, diarrhea, or dementia.
C: Scurvy is caused by vitamin C deficiency and is characterized by bleeding gums, weakness, and fatigue, not the symptoms mentioned in the question.
Irbesartan (an angiotensin-II receptor antagonist) is contraindicated in:
- A. Left ventricular failure
- B. Asthma
- C. Bilateral renal artery stenosis
- D. Diabetic nephropathy
Correct Answer: C
Rationale: Irbesartan is contraindicated in bilateral renal artery stenosis (C) due to risk of renal failure and pregnancy (D) due to fetal harm; it is beneficial in heart failure (A) and diabetic nephropathy (E), and safe in asthma (B).
Which of the following drugs is believed to improve microcirculation in peripheral vascular diseases by promoting RBC flexibility?
- A. Cyclandelate
- B. Theophyline
- C. Pentoxiphyline
- D. Nicotinic acid
Correct Answer: C
Rationale: Pentoxifylline improves RBC flexibility and reduces blood viscosity, enhancing microcirculation.