Osteosarcoma is the most common primary malignant bone tumor in children and adolescents; it has multiple subtypes and requires different modalities of treatment including surgery and chemotherapy. Of the following, the subtype of osteosarcoma which is treated by surgery alone is

Correct Answer: D

Rationale: Periosteal osteosarcoma is often treated with surgery alone if margins are clear.

Correct Answer: D

Rationale: The most common buffer system in the body is the bicarbonate-carbonic system. This system plays a crucial role in maintaining the pH balance in the blood. The bicarbonate ion (HCO3-) acts as a weak base, while carbonic acid (H2CO3) acts as a weak acid. The balance between these two components helps to regulate the pH of the blood.

Correct Answer: D

Rationale: The nurse should include in the explanation that in managing pediculosis capitis, it is necessary to remove nits with an extra-fine-tooth comb or tweezers since nits are attached to the hair shaft and can be difficult to wash out with regular shampoo. Removing the nits is crucial to prevent reinfestation, as they can hatch and start the cycle again. Cutting the hair shorter is not necessary unless the infestation is severe. It is important to distinguish viable (live) nits from nonviable (dead) ones and remove only the viable ones as the nonviable ones do not pose a threat of reinfestation.

Correct Answer: B

Rationale: Concomitant chemotherapy and radiotherapy are essential to manage ruptured Wilms tumor and reduce the risk of dissemination.

Correct Answer: A

Rationale: Pilocytic astrocytomas are generally low-grade and less responsive to chemotherapy compared to other listed tumors.