Nokea
Dilatation of the peripheral arterial blood vessels can be caused by:
- A. thromboxane A2
- B. adenosine diphosphate
- C. endothelin
- D. prostaglandins
Correct Answer: D
Rationale: Prostaglandins, particularly prostacyclin (PGI2), are potent vasodilators. Thromboxane A2, adenosine diphosphate, and endothelin are vasoconstrictors and do not cause peripheral arterial dilatation.
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Mr. K., aged 60 years, has a diagnosis of transient ischemic attack. An essential aspect of his history that needs to be documented is
- A. sudden, brief loss of sensory, motor, or visual function
- B. determining if he has any allergies
- C. any history of neurologic disease
- D. his medication history, both prescribed and over-the-counter
Correct Answer: A
Rationale: Sudden neurological deficits are hallmark symptoms of TIA.
A patient with Guillain-Barré syndrome asks whether he is going to die as the paralysis spreads toward his chest. In responding to the patient, what should the nurse know to be able to answer this question?
- A. Patients who require ventilatory support almost always die.
- B. Death occurs when nerve damage affects the brain and meninges.
- C. Most patients with Guillain-Barré syndrome make a complete recovery.
- D. If death can be prevented, residual paralysis and sensory impairment are usually permanent.
Correct Answer: C
Rationale: Most patients recover fully, though some may have long-term deficits.
A nurse is assessing a client on the musculoskeletal floor and identifies symptoms of weak pulses, dusky color in the ankles, and 3+ local edema. Which of the following does the nurse suspect to be an issue with this client?
- A. Problems with circulation
- B. Problems with sensation
- C. Problems with mobility
- D. Problems with pain
Correct Answer: A
Rationale: Weak pulses, dusky color, and edema strongly suggest circulatory issues.
What is the role of semaphorins and Eph ligands in development of the nervous system?
- A. The semaphorins and Eph ligands are growth factors that stimulate cell division of neurons.
- B. The semaphorins and Eph ligands act as signals for the outgrowth of neuronal growth cones; in general, both lead growth cones to turn away.
- C. The semaphorins and Eph ligands act as signals for the outgrowth of neuronal growth cones; in general, both lead growth cones to come toward them.
- D. The semaphorins and Eph ligands are cell-cell adhesion molecules that bind adjacent neurons together.
Correct Answer: B
Rationale: Semaphorins and Eph ligands act as guidance cues for growing axons. They generally function as repulsive signals, causing growth cones to turn away from inappropriate regions. This ensures precise navigation of axons to their correct targets, which is essential for establishing functional neural circuits.
The Bell's phenomenon:
- A. occurs during normal blinking
- B. if absent suggests brain stem disease
- C. is absent in Bell's palsy
- D. is reduced or absent in patients with thyroid orbitopathy
Correct Answer: D
Rationale: The Bell's phenomenon, an upward and outward eye movement during eyelid closure, is reduced or absent in thyroid orbitopathy due to restricted eye movements. It is not typically absent in Bell's palsy or brain stem disease.