Which of the following cell types would be the first to aid in killing bacteria to prevent infection in his hand?

Correct Answer: B

Rationale: Neutrophils are the first responders to a bacterial infection. They are phagocytes that engulf and destroy bacteria, playing a crucial role in the early stages of the immune response. Eosinophils are primarily involved in combating parasitic infections and allergic reactions, not bacterial infections. Leukotrienes are signaling molecules that contribute to inflammation and immune responses, but they are not cells. Monocytes are another type of white blood cell that differentiates into macrophages and dendritic cells, playing a role in immune response but not as immediate as neutrophils.

Correct Answer: B

Rationale: The correct answer is B: normal and termed the postictal period. The postictal period is a common phase following a seizure where the individual may experience fatigue, confusion, or sleepiness. It is a normal part of the seizure event and does not necessarily indicate a serious issue. Choice A is incorrect because feeling tired and falling asleep after a seizure is not an ominous sign but rather a typical postictal symptom. Choice C is incorrect as there is no indication in the scenario provided that links the symptoms to an underlying brain tumor. Choice D is incorrect because the absence of focal neurologic deficits does not make the postictal period worrisome.

Correct Answer: B

Rationale: Multiple dark bands on the nails can be associated with malignant melanoma, a serious type of skin cancer. While dark bands on the nails can sometimes be a normal variant, they should not be ignored as they could also be a sign of a serious condition like melanoma. Nail fungus typically presents with different symptoms such as thickened, discolored, or brittle nails. Dark bands on the nails are not directly associated with aging.

Correct Answer: C

Rationale: Osteosarcoma is an aggressive bone tumor that most commonly arises in the bone marrow of long bones, such as the femur or tibia. Choice A is incorrect as osteosarcoma is not a slow-growing tumor but rather a fast-growing one. Choice B is incorrect as osteosarcoma is not typically solitary but can involve multiple lesions. Choice D is incorrect as osteosarcoma primarily affects the medullary (marrow) cavity of bones, rather than infiltrating the trabeculae in spongy bone and surrounding tissue.

Correct Answer: D

Rationale: Women with breast cancer due to a BRCA1 gene mutation commonly have a triple-negative breast cancer subtype, which means they are negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2). This subtype tends to be more aggressive and harder to treat. Choice A is incorrect as they are typically negative for HER2. Choice B is incorrect because they are usually negative for estrogen receptor. Choice C is incorrect as they are usually negative for progesterone receptor and HER2.

Correct Answer: D

Rationale: Anemia of chronic inflammation is typically characterized by normochromic (normal hemoglobin content) and normocytic (normal cell size) red blood cells. Choice A, hypochromic and microcytic, is incorrect because hypochromic refers to reduced hemoglobin content and microcytic refers to smaller than normal red blood cells, which are not typically seen in anemia of chronic inflammation. Choice B, hypochromic and macrocytic, is also incorrect as macrocytic refers to larger than normal red blood cells. Choice C, normochromic and microcytic, is incorrect because microcytic red blood cells are smaller than normal. Therefore, the correct classification for anemia of chronic inflammation is normochromic and normocytic.

Correct Answer: D

Rationale: The correct answer is 'Low-density lipoprotein (LDL) receptor mutation with defects in breakdown.' Primary hypercholesteremia is mainly caused by mutations in the LDL receptor, leading to impaired clearance of LDL cholesterol from the blood. This results in high levels of LDL cholesterol in the bloodstream. Choices A, B, and C are incorrect because they do not directly relate to the primary cause of primary hypercholesteremia.

Correct Answer: B

Rationale: The correct answer is B: Immune complex deposition, increased capillary permeability, and cellular proliferation. Acute glomerulonephritis is characterized by inflammation of the glomeruli in the kidneys. This inflammation leads to the deposition of immune complexes, increased capillary permeability, and cellular proliferation, which collectively contribute to a decreased glomerular filtration rate. Choice A is incorrect as decreased renal-induced constriction of the renal arteries would not directly result in decreased glomerular filtration rate. Choice C is incorrect as necrosis of nephrons due to increased kidney interstitial hydrostatic pressure would affect kidney function differently. Choice D is incorrect as scar tissue formation in the proximal convoluted tubule due to toxin-induced collagen synthesis is not a typical feature of acute glomerulonephritis.

Correct Answer: B

Rationale: Postoperative adhesions are a common cause of mechanical small intestine obstruction. Adhesions can form after abdominal surgery, causing bands of scar tissue that may twist or pull the intestines, leading to obstruction. This is a more common cause compared to infection, tumors, or foreign bodies. Infection may lead to inflammation but is not a typical cause of mechanical obstruction. Tumors and foreign bodies can cause blockages but are less common than postoperative adhesions.