For lymphadenopathy with suspected lymphoma, most appropriate diagnostic test?

Correct Answer: C

Rationale: The correct answer is C: Surgical lymph node excision. This is the most appropriate diagnostic test for lymphadenopathy with suspected lymphoma as it provides an adequate tissue sample for definitive diagnosis through histopathological examination. Fine-needle aspirate (B) may not yield enough tissue for accurate diagnosis. Abdominal x-ray (A) and bone scan (D) are not specific for assessing lymphoma and do not provide tissue for histological examination. Surgical excision allows for comprehensive evaluation of the lymph node architecture and cellular characteristics, aiding in accurate diagnosis and treatment planning.

Correct Answer: C

Rationale: The correct answer is C: Lymphocyte predominance. Reed-Sternberg cells are characteristic of Hodgkin's lymphoma. In this type, Reed-Sternberg cells are infrequent, and popcorn cells are present. This presentation is typical of lymphocyte predominance subtype. Nodular sclerosis (A) is characterized by bands of collagen separating nodules, mixed cellularity (B) has a mixed cell population with frequent Reed-Sternberg cells, and lymphocyte depleted (D) has few lymphocytes and more Reed-Sternberg cells.

Correct Answer: D

Rationale: The correct answer is D because iron is better absorbed in the ferrous form compared to the ferric form. Ferrous iron is more soluble and readily absorbed by the body through the duodenum and upper small intestine. Intrinsic factor is needed for the absorption of vitamin B12, not iron (Choice B). Ascorbic acid actually enhances iron absorption by reducing ferric iron to the more absorbable ferrous form, so Choice C is incorrect. Large intestine absorption (Choice A) is not a significant route for iron absorption in the body.

Correct Answer: C

Rationale: Platelets play a crucial role in the process of hemostasis after vascular injury. When a blood vessel is damaged, platelets adhere to the site and change shape to form a plug, a process known as platelet aggregation. This is important for stopping bleeding. Vasodilation (choice A) typically occurs after vasoconstriction to help with blood flow. Clotting factors (choice B) are essential in the coagulation cascade but not directly involved in platelet aggregation. Serotonin (choice D) is released by platelets during aggregation but does not directly stimulate the process. Therefore, the correct answer is C as platelets changing shape is a key step in platelet aggregation during vascular injury.

Correct Answer: D

Rationale: The correct answer is D: Thymus. The thymus is a primary lymphoid organ where T lymphocytes mature. It plays a crucial role in the development of the immune system. Lymph nodes (A), spleen (B), and Peyer's patches (C) are considered secondary lymphoid organs where immune responses are initiated but not where lymphocytes mature. Thymus is the only choice that fits the criteria of being a primary lymphoid organ.