Indicate the drug belonging to antagonists of heparin:

Correct Answer: D

Rationale: The correct answer is D: Protamine sulfate. Protamine sulfate is an antagonist of heparin because it binds to heparin molecules, forming a stable complex that neutralizes the anticoagulant effects of heparin. This interaction helps to reverse the effects of heparin in cases of heparin overdose or when immediate cessation of anticoagulation is required. A: Aspirin is an antiplatelet agent that inhibits platelet aggregation by irreversibly inhibiting cyclooxygenase. It is not an antagonist of heparin. B: Dicumarol is a vitamin K antagonist that inhibits the synthesis of vitamin K-dependent clotting factors. It is not an antagonist of heparin. C: Dalteparin is a low-molecular-weight heparin that acts as an anticoagulant by inhibiting the activity of factor Xa. It is not an antagonist of heparin. In summary, Protamine sulfate

Correct Answer: D

Rationale: The correct answer is D: Nifedipine. Nifedipine is a calcium channel blocker that directly acts on vascular smooth muscle to cause vasodilation by inhibiting calcium influx. Labetalol and Clonidine are alpha and beta blockers, Enalapril is an ACE inhibitor, which all indirectly cause vasodilation. Therefore, Nifedipine is the only directly acting vasodilator among the choices.

Correct Answer: A

Rationale: The correct answer is A because hormones are indeed products of endocrine gland secretion. Endocrine glands release hormones directly into the bloodstream to regulate various physiological processes. Choice B is incorrect as hormones are not mediators of the inflammatory process. Choice C is wrong because hormones are not by-products of tissue metabolism but rather specific signaling molecules. Choice D is incorrect as hormones are not products of exocrine gland secretion but rather endocrine glands.

Correct Answer: A

Rationale: The correct answer is A because thiazolidinediones work by activating peroxisome proliferator-activated receptor gamma (PPAR-γ), which leads to increased glucose uptake and metabolism in muscle and adipose tissues, thereby reducing insulin resistance. It does not reduce carbohydrate absorption from the gut (choice B) or stimulate beta islet cells to produce insulin (choice C). Therefore, the correct answer is A as it directly addresses the mechanism of action of thiazolidinediones.

Correct Answer: D

Rationale: Rationale: Glucocorticoids are indicated for a wide range of conditions due to their anti-inflammatory and immunosuppressive effects. A: Glucocorticoids are used in both chronic (Addison's disease) and acute adrenocortical insufficiency to replace deficient cortisol levels. B: Glucocorticoids are essential for preventing rejection in organ transplant recipients by suppressing the immune response. C: Glucocorticoids are effective in managing inflammatory conditions of bones and joints by reducing inflammation and pain. Therefore, the correct answer is D because glucocorticoids are indicated for all the mentioned conditions due to their diverse mechanisms of action.