Nokea
One principal function of the Class I and Class II major histocompatibility complex S proteins is to
- A. transduce the signal to the T-cell interior following antigen binding
- B. mediate immunoglobulin class switching
- C. present antigen for recognition by the T-cell antigen receptor
- D. stimulate production of interleukins
Correct Answer: C
Rationale: The correct answer is C because Class I and Class II MHC proteins present antigens to T-cell receptors for immune response activation. Class I MHC presents endogenous antigens to CD8+ T cells, while Class II MHC presents exogenous antigens to CD4+ T cells. Choice A is incorrect because MHC proteins do not transduce signals. Choice B is incorrect because MHC proteins do not mediate immunoglobulin class switching. Choice D is incorrect because MHC proteins do not directly stimulate interleukin production.
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A patient with advanced AIDS has a nursing diagnosis of impaired memory related to neurologic changes. In planning care for the patient, what should the nurse set as the highest priority?
- A. Maintain a safe patient environment
- B. Provide a quiet, nonstressful environment to avoid overstimulation
- C. Use memory cues such as calendars and clocks to promote orientation
- D. Provide written instructions of directions to promote understanding and orientation
Correct Answer: A
Rationale: Safety is paramount for cognitively impaired patients. Preventing falls and ensuring access to necessities takes precedence over other interventions.
What type of dressing will the nurse most likely use for the patient in Question 14?
- A. Dry, sterile dressing
- B. Absorptive dressing
- C. Negative pressure wound therapy
- D. Telfa dressing with antibiotic ointment
Correct Answer: B
Rationale: Absorptive dressings are ideal for wounds with moderate exudate, helping maintain a moist environment conducive to healing while preventing maceration.
Which of the following factors makes it important for the nurse to provide special care to older clients with immune system disorders?
- A. Age-related changes
- B. Poor diet
- C. Use of multiple drugs (polypharmacy)
- D. Reduced activity levels
Correct Answer: A
Rationale: Age-related changes in the immune system known as immunosenescence make older adults more susceptible to infections and less responsive to vaccines.
Which organ is most commonly affected in sarcoidosis?
- A. Kidney
- B. Lungs
- C. Liver
- D. Thyroid
Correct Answer: B
Rationale: The correct answer is B: Lungs. Sarcoidosis is a systemic inflammatory disease that primarily affects the lungs in about 90% of cases. This is due to the formation of granulomas, inflammatory nodules, in the lung tissue. Kidney (A), Liver (C), and Thyroid (D) are less commonly affected organs in sarcoidosis. Kidney involvement occurs in about 20-30% of cases, liver involvement in about 10-30% of cases, and thyroid involvement is relatively rare. Therefore, based on the prevalence of organ involvement in sarcoidosis, the lungs are the most commonly affected organ.
Which of the following is a clinical feature of Grave's disease?
- A. Pulmonary fibrosis
- B. Exophthalmos and goiter
- C. Skin vasculitis
- D. Eczematous reaction
Correct Answer: B
Rationale: The correct answer is B: Exophthalmos and goiter. In Grave's disease, there is an overproduction of thyroid hormones leading to hyperthyroidism. Exophthalmos (bulging eyes) and goiter (enlarged thyroid gland) are classic clinical features due to autoimmune stimulation of thyroid-stimulating hormone receptors. Pulmonary fibrosis (A) is not typically associated with Grave's disease. Skin vasculitis (C) and eczematous reaction (D) are also not commonly seen in Grave's disease.