Transdermal estradiol differs from oral estrogen therapy in that it:

Correct Answer: D

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

Correct Answer: D

Rationale: The correct answer is D because both Raloxifene (a selective estrogen receptor modulator) and Alendronate (a bisphosphonate) are commonly used to treat osteoporosis. Raloxifene helps prevent bone loss and reduces fracture risk, while Alendronate slows down bone breakdown. Pamidronate (choice C) is not typically used for osteoporosis treatment. Therefore, choices A, B, and C are incorrect.

Correct Answer: D

Rationale: The correct answer is D: Calcitriol. Calcitriol is the active form of vitamin D and is the most suitable preparation for vitamin D dependent rickets as it directly increases calcium absorption in the intestines and promotes bone mineralization. Calcitriol is essential for regulating calcium and phosphorus levels in the body. Choice A, Calciferol, is a general term for vitamin D compounds and is not specific enough for rickets treatment. Choice B, Cholecalciferol, is the precursor form of vitamin D and needs to be converted to calcitriol in the body. Choice C, Calcifediol, is an intermediate form that also requires conversion to calcitriol for biological activity. Therefore, calcitriol is the most appropriate choice for treating vitamin D dependent rickets due to its direct action on calcium metabolism and bone health.

Correct Answer: B

Rationale: The correct answer is B: Parathormone. Parathormone stimulates osteoclast activity, which leads to increased bone resorption. Estrogens (choice A) actually inhibit bone resorption. Bisphosphonates (choice C) are used to decrease bone resorption. Calcitonin (choice D) also inhibits bone resorption by blocking osteoclast activity. Therefore, the correct choice is parathormone as it directly accelerates bone resorption by stimulating osteoclasts.

Correct Answer: A

Rationale: 1. Oxytocin is a hormone that primarily functions in inducing uterine contractions and milk let-down. 2. Vasoconstriction is not a known physiological action of oxytocin. 3. Increased water reabsorption, mammary contraction, and prostaglandin release are all effects of oxytocin. 4. Therefore, the correct answer is A: Vasoconstriction, as it is not a typical action of oxytocin.