Which of the following statements concerning nootropics is not correct?

Correct Answer: B

Rationale: The correct answer is B because nootropics do not stimulate the bulbar respiratory center. Nootropics are substances that enhance cognitive function and brain health. Choice A is correct as nootropics are known to improve cognitive functions. Choice C is also correct as they enhance neuronal synapses. Choice D is incorrect as nootropics are not designed to protect against damaging influences but rather to enhance brain function. Therefore, choice B is the correct answer because nootropics do not have a direct effect on the bulbar respiratory center.

Correct Answer: B

Rationale: The correct answer is B: Desoxiribonuclease. Desoxiribonuclease is a proteolytic enzyme that breaks down DNA molecules. Proteolytic enzymes are enzymes that break down proteins into smaller peptides or amino acids. Potassium iodide, Carbocysteine, and Acetylcysteine are not proteolytic enzymes, they are used for different purposes such as treating respiratory conditions or as expectorants. Therefore, B is the correct answer as it is the only option that is a proteolytic enzyme.

Correct Answer: C

Rationale: The correct answer is C: Methotrexate. Methotrexate is a chemotherapy drug that inhibits cell division, including erythroid precursors, thereby suppressing erythrogenesis. Iron dextran, vitamin B12, and folic acid are essential for erythrogenesis by supporting hemoglobin synthesis and red blood cell production. Iron dextran provides iron for hemoglobin synthesis, vitamin B12 is required for DNA synthesis in erythroid precursors, and folic acid is essential for DNA synthesis and cell division. Therefore, methotrexate is the only drug among the choices that does not stimulate erythrogenesis.

Correct Answer: B

Rationale: Step-by-step rationale: 1. Digibind (Digoxin immune fab) is the best choice in severe digitalis intoxication as it binds to digoxin, reducing its effects. 2. Lidocaine is used for cardiac arrhythmias but not specific to digoxin toxicity. 3. Oral potassium supplementation can worsen digoxin toxicity by increasing intracellular potassium. 4. Reducing the dose of the drug is not effective in severe intoxication. Summary: - Digibind is specific for digoxin toxicity by binding to the drug. - Lidocaine, oral potassium, and reducing the drug dose are not effective in severe digitalis intoxication.

Correct Answer: D

Rationale: The correct answer is D, "All of the above." Calcium channel blockers are commonly used for angina pectoris, hypertension, and supraventricular tachyarrhythmias. They work by blocking the entry of calcium into the cells, leading to vasodilation, decreased myocardial contractility, and reduced heart rate. This helps in managing angina by reducing oxygen demand, controlling blood pressure, and treating certain types of arrhythmias. Therefore, the main clinical use of calcium channel blockers encompasses all three conditions mentioned in the choices.