Gemfibrozil (Lopid) increases concentrations of HDL cholesterol more than clofibrate (Atromid-S). This consideration is:

Correct Answer: A

Rationale: The correct answer is A: TRUE. Gemfibrozil (Lopid) is known to be more effective at increasing HDL cholesterol levels compared to clofibrate (Atromid-S). This is supported by clinical studies showing a greater impact on HDL concentrations with gemfibrozil. Choice B is incorrect as it contradicts the established evidence. Choices C and D are also incorrect as they do not accurately reflect the comparative efficacy between Gemfibrozil and clofibrate in increasing HDL cholesterol levels.

Correct Answer: B

Rationale: The correct answer is B: Amiloride (Midamor). It is a potassium-sparing diuretic that blocks Na+ channels in the collecting tubules. Amiloride specifically targets the epithelial sodium channels in the collecting tubules, leading to decreased sodium reabsorption and potassium retention. Acetazolamide (A) is a carbonic anhydrase inhibitor, Furosemide (C) is a loop diuretic that inhibits the Na+-K+-2Cl- symporter, and Hydrochlorothiazide (D) is a thiazide diuretic that inhibits the Na+-Cl- symporter in the distal convoluted tubule.

Correct Answer: B

Rationale: The correct answer is B: Cefaclor. Cefaclor belongs to the cephalosporin class of antibiotics, specifically a second-generation cephalosporin. Cephalosporins are beta-lactam antibiotics that inhibit bacterial cell wall synthesis. Streptomycin (A) is an aminoglycoside antibiotic, Phenoxymethylpenicillin (C) is a penicillin antibiotic, and Erythromycin (D) is a macrolide antibiotic. These choices do not belong to the cephalosporin class.

Correct Answer: D

Rationale: The correct answer is D: Rifampin. Rifampin is an antimycobacterial drug that is commonly used to treat tuberculosis and other mycobacterial infections. It works by inhibiting the RNA polymerase enzyme in mycobacteria, leading to the suppression of bacterial growth. Isoniazid (Choice A) is also used for tuberculosis treatment, but it is not classified as an antibiotic. PAS (Choice B) is an antimycobacterial drug but is not an antibiotic. Ethambutol (Choice C) is also used to treat tuberculosis, but it works by inhibiting cell wall synthesis rather than RNA polymerase. Therefore, the correct choice is Rifampin as it directly targets the mycobacterial RNA polymerase enzyme, making it an effective antibiotic for treating mycobacterial infections.

Correct Answer: A

Rationale: Niclosamide inhibits oxidative phosphorylation by blocking the electron transport chain in helminthes. It disrupts their energy production, leading to paralysis and death. Piperazine acts on GABA receptors, Praziquantel disrupts the parasite's tegument, and Mebendazole inhibits microtubule function. Therefore, Niclosamide is the correct choice for inhibiting oxidative phosphorylation in helminthes.