The nurse is performing an assessment on the patient who is in bilateral Buck traction. Which finding indicates the need to reposition the patient?

Correct Answer: C

Rationale: The correct answer is C because if the patient's feet are against the footboard in Buck traction, it can cause pressure ulcers and compromise circulation. Repositioning the patient is necessary to ensure proper alignment and prevent complications. Incorrect choices: A: The patient's heels not touching the mattress can be due to the traction pulling the legs in a specific position. B: Rewrapping the elastic bandages may be necessary for proper traction maintenance but doesn't indicate immediate need for repositioning. D: The weights hanging free is a normal finding in Buck traction and indicates proper traction application.

Correct Answer: B

Rationale: The correct answer is B because migrating dendritic cells do not enter the draining lymph node (LN) via high endothelial venules (HEV); instead, they enter through afferent lymphatic vessels. HEVs are specialized post-capillary venules in LN where lymphocytes enter from the bloodstream. Dendritic cells, carrying antigens from tissues, travel via afferent lymphatic vessels to reach the LN where they present antigens to lymphocytes. Option A is correct as antigens in tissues reach LN via afferent lymphatic vessels. Option C is correct as infection-induced signals can increase blood flow to LN, facilitating lymphocyte migration. Option D is incorrect because the thoracic duct returns lymph back to the bloodstream, not specifically lymphocytes.

Correct Answer: D

Rationale: The correct answer is D because multiple sclerosis (MS) typically affects individuals between 20-50 years old, with the most common age of onset being between 20-40 years. MS is not primarily a disease of older individuals over 65 years. Choices A, B, and C are incorrect because various HLA alleles have been associated with MS susceptibility, females are indeed more at risk for MS than males, and there is a known North-South gradient in MS incidence, with higher rates reported for populations living farther from the equator.

Correct Answer: D

Rationale: Protease inhibitors interfere with the final step in HIV replication, which is the cleavage of the polyprotein into individual functional proteins. Inhibiting protease prevents the formation of mature infectious viral particles. This step occurs after reverse transcription of viral RNA into DNA, making choice D the correct answer. Choices A, B, and C are incorrect because protease inhibitors do not affect the release of new viral particles, processing of gp160, or the proviral stage of HIV replication.

Correct Answer: B

Rationale: The correct answer is B: To orchestrate and drive immune responses. Cytokines are signaling molecules that coordinate various aspects of the immune response, such as inflammation, cell proliferation, and differentiation. They regulate communication between immune cells to mount an effective defense against pathogens. A: To act as a physical barrier to pathogens - Incorrect. Physical barriers include skin and mucous membranes, not cytokines. C: To destroy red blood cells - Incorrect. Cytokines are not involved in destroying red blood cells. D: To generate antibodies - Incorrect. While cytokines can influence antibody production, their primary role is not in generating antibodies.