Graft-versus-host disease prevention in transfusion?

Correct Answer: B

Rationale: The correct answer is B: Irradiating blood components. This is because irradiation of blood components helps prevent graft-versus-host disease by inactivating T lymphocytes present in the transfused blood. This decreases the risk of these donor T cells attacking the recipient's tissues, which is the underlying mechanism of graft-versus-host disease. Explanation of other choices: A: Packed cells - While packed red blood cells are less likely to cause a reaction compared to whole blood, they do not prevent graft-versus-host disease. C: Fresh whole blood - Fresh whole blood does not address the specific mechanism of graft-versus-host disease prevention like irradiation does. D: Crystalloid replacement - Crystalloid replacement does not have any impact on preventing graft-versus-host disease as it does not affect the T lymphocytes present in the transfused blood components.

Correct Answer: D

Rationale: Step-by-step rationale for why answer D is correct: 1. An antigen is a substance that stimulates the production of antibodies. 2. Antigens can be proteins, carbohydrates, or other molecules that the immune system recognizes as foreign. 3. Antigens trigger the immune system to produce antibodies to neutralize or eliminate the foreign substance. 4. Therefore, the correct answer is D as it accurately describes the role of antigens in stimulating antibody production. Summary: A, B, and C are incorrect because: A: Antigens are not proteins themselves but can be recognized by antibodies. B: Antigens do not inhibit microorganism growth; they stimulate immune responses. C: Antigens do not directly stimulate antibody production; they trigger the immune system to produce antibodies in response to foreign substances.

Correct Answer: A

Rationale: The correct answer is A because rivaroxaban is a direct factor Xa inhibitor that works by inhibiting thrombin formation. Thrombin is a key enzyme in the blood coagulation pathway, and by inhibiting it, rivaroxaban prevents the formation of fibrin clots. Choices B and D are incorrect because rivaroxaban does not directly inhibit fibrinogen or work against vitamin K. Choice C is also incorrect as rivaroxaban does not actually "thin" the blood but rather prevents the formation of clots by inhibiting thrombin.

Correct Answer: B

Rationale: The correct answer is B because changes in dentition with cavities are not directly related to aging; they can occur at any age due to poor oral hygiene. Progressive hair loss, thickened/discolored nail beds, and dry skin are common age-related changes. Hair loss is linked to hormonal changes, nail bed changes may indicate poor circulation, and dry skin is a result of decreased oil production. Therefore, B is the correct answer as it does not specifically relate to age-related changes.

Correct Answer: D

Rationale: The correct answer is D: An HIV infection. The presence of antibodies to the AIDS virus in the blood indicates that the client has been exposed to HIV and their immune system has produced antibodies against it. This does not mean the client is immune to HIV (choice A) as HIV infection can still occur. It also does not necessarily mean the immune system is intact (choice B) as the presence of antibodies can indicate exposure to the virus. Additionally, the presence of antibodies does not indicate the client has an AIDS-related complication (choice C) as AIDS is a later stage of HIV infection.