A patient diagnosed with alcoholism has questions about his medications. The nurse correctly explains that alcoholism can be associated with deficiency of which vitamin?

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: Combination chemotherapy is used to target cancer cells through multiple mechanisms, reducing the likelihood of resistance. Single-agent therapy often leads to the development of resistant cell lines, as cancer cells can adapt to the drug. By using a combination of drugs with different mechanisms of action, the treatment can more effectively kill cancer cells and prevent resistance. While two drugs may increase efficacy, the primary rationale is to overcome resistance. Larger doses of single agents are not the main reason for combination therapy.

Correct Answer: D

Rationale: Systolic hypertension (168 mmHg) in the elderly increases cardiovascular risk, despite normal diastolic (80 mmHg). Echo isn't first-line without organ damage signs (normal ECG). Reassurance ignores systolic risk; treatment is indicated (>160 mmHg). Doxazosin, an alpha-blocker, is less preferred initially due to hypotension risk. Ramipril, an ACE inhibitor, is effective, but amlodipine, a calcium channel blocker, is most appropriate per guidelines (e.g., NICE) for isolated systolic hypertension in the elderly, offering vascular protection and tolerability. Its efficacy reduces stroke and MI risk, critical at this age.

Correct Answer: A

Rationale: Butoxamine (β2 antagonist) and terbutaline (β2 agonist) target the same receptor, a true pair. Phenoxybenzamine (α-adrenergic antagonist) and cyclopentolate (muscarinic antagonist) act on different receptors. Pilocarpine and bethanechol are both muscarinic agonists, not antagonist-agonist. Oxymetazoline (α-agonist) and dobutamine (β1-agonist) differ in receptor specificity. Bromocriptine and pramipexole are dopamine agonists. The β2 pair is a classic example in pharmacology, illustrating receptor-specific antagonism and agonism.

Correct Answer: C

Rationale: Androgens, mainly testosterone, are secreted by the testes' Leydig cells, activated by pituitary LH, making the testes the source. FSH regulates sperm, not androgens. GnRH from the hypothalamus triggers LH/FSH release, indirectly affecting androgens. The pituitary releases LH/FSH, not androgens. The testes' direct secretion role is fundamental, driven by LH, distinguishing it from regulatory hormones.