Which of these groups of drugs is used for asthma treatment?

Correct Answer: D

Rationale: Correct Answer: D Rationale: 1. Methylxanthines (e.g., theophylline) help relax bronchial smooth muscles. 2. M-cholinoblocking agents (e.g., ipratropium) block the action of acetylcholine, reducing bronchoconstriction. 3. Beta2-stimulants (e.g., albuterol) relax bronchial smooth muscles and dilate airways. 4. "All of above" encompasses all three drug groups, covering various mechanisms to manage asthma symptoms effectively.

Correct Answer: B

Rationale: Step-by-step rationale for why B (Dobutamine) is the correct answer: 1. Dobutamine is a selective beta-1 agonist, primarily targeting β1-adrenergic receptors in the heart. 2. It increases cardiac contractility and heart rate, making it useful in treating heart failure and cardiogenic shock. 3. Digoxin (A) is a cardiac glycoside, Amrinone (C) is a phosphodiesterase inhibitor, and Dopamine (D) acts on multiple receptors. 4. Thus, the specific action of dobutamine on beta-1 receptors distinguishes it as the correct choice.

Correct Answer: C

Rationale: Rationale: Atenolol is a beta-adrenoceptor-blocking drug, specifically a beta-1 selective blocker. It works by reducing the heart rate and blood pressure, making it effective in treating angina. Dipyridamole is a vasodilator, not a beta blocker. Validol is a mild sedative and antispasmodic, not a beta blocker. Alinidine is an antiarrhythmic drug acting on the alpha-2 adrenergic receptors, not a beta blocker. Therefore, Atenolol is the correct choice as it directly targets beta-adrenoceptors to reduce anginal symptoms.

Correct Answer: C

Rationale: The correct answer is C: Plasmoexpanders. Plasmoexpanders are used to increase circulating blood volume in cases of hypovolemic shock. By increasing plasma volume, plasmoexpanders help restore tissue perfusion and improve blood pressure. Positive inotropic drugs (A) increase the force of heart contractions, vasoconstrictors (B) constrict blood vessels, and analeptics and tonics (D) stimulate the central nervous system - none of which directly address the issue of reduced circulating blood volume in shock. Plasmoexpanders are the most appropriate choice for treating hypovolemic shock as they specifically target the underlying cause of reduced blood volume.

Correct Answer: A

Rationale: The correct answer is A. Daily administration of large doses of iodides causes involution of the thyroid gland. Iodides inhibit thyroid hormone synthesis, leading to a decrease in thyroid size. This effect peaks in about two weeks. Choice B is incorrect as iodides actually decrease vascularity of the thyroid gland. Choice C is incorrect because iodides increase the storage of colloid in the thyroid gland. Choice D is incorrect as iodides make the thyroid gland softer and more vascular, not firm and less vascular.