Nokea
Nicotinic receptors are blocked by which of the following:
- A. Propranolol
- B. Trimetaphan
- C. Prazosin
- D. Pilocarpine
Correct Answer: B
Rationale: The correct answer is B: Trimetaphan. Nicotinic receptors are blocked by non-depolarizing neuromuscular blockers like Trimetaphan. Propranolol (A) is a beta-blocker, Prazosin (C) is an alpha-1 blocker, and Pilocarpine (D) is a muscarinic agonist, none of which block nicotinic receptors. Therefore, Trimetaphan (B) is the only choice that directly blocks nicotinic receptors.
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Mr. Weber, an insulin-dependent diabetic, states that in the afternoon he has occasional severe reactions during which he becomes unconscious. In planning his care, which of the following nursing actions is most appropriate?
- A. Placing a tube of commercially prepared glucose paste at his bedside
- B. Administering regular insulin
- C. Checking his level of consciousness every hour
- D. Keeping a supply of orange juice in the refrigerator
Correct Answer: A
Rationale: For a patient with severe hypoglycemic reactions, it's essential to have a quick source of glucose on hand, like glucose paste, to treat unconsciousness from low blood sugar.
Selective beta2 stimulants frequently cause:
- A. Skeletal muscle tremors
- B. Tolerance
- C. Tachycardia
- D. All of the above
Correct Answer: D
Rationale: Selective beta2 stimulants typically cause skeletal muscle tremors due to their action on beta2 receptors in skeletal muscles. They can also lead to tolerance with prolonged use, requiring higher doses for the same effect. Additionally, they can cause tachycardia by stimulating beta2 receptors in the heart. Therefore, all of the above choices (A, B, and C) are correct.
A benign tumor of the adrenal medulla:
- A. causes life-threatening low blood pressure.
- B. is called a pheochromocytoma.
- C. causes Addison’s disease.
- D. causes excess secretion of cortisol.
Correct Answer: B
Rationale: The correct answer is B: A benign tumor of the adrenal medulla is called a pheochromocytoma. Pheochromocytomas are tumors that arise from the adrenal medulla, leading to overproduction of catecholamines like adrenaline and noradrenaline. This excess secretion can result in symptoms such as high blood pressure, palpitations, and sweating. Choices A and C are incorrect because a benign tumor of the adrenal medulla typically causes high blood pressure, not low blood pressure or Addison's disease. Choice D is incorrect because excess cortisol secretion is associated with conditions like Cushing's syndrome, not pheochromocytoma.
Which layer of cervical fascia forms the false capsule of thyroid gland?
- A. Carotid sheath
- B. Investing layer
- C. Pretracheal fascia
- D. Prevertebral fascia
Correct Answer: C
Rationale: The correct answer is C: Pretracheal fascia. This layer surrounds the thyroid gland, forming the false capsule. It separates the thyroid from the strap muscles anteriorly and the trachea and esophagus posteriorly. The Carotid sheath (A) encloses the common carotid artery, internal jugular vein, and vagus nerve. The Investing layer (B) covers the sternocleidomastoid and trapezius muscles. The Prevertebral fascia (D) surrounds the vertebral column and deep neck muscles, not directly related to the thyroid gland.
What is a cause of primary hypothyroidism in adults?
- A. Malignant or benign thyroid nodules
- B. Surgical removal or failure of the pituitary gland
- C. Surgical removal or radiation of the thyroid gland
- D. Autoimmune-induced atrophy of the thyroid gland
Correct Answer: D
Rationale: Primary hypothyroidism in adults is commonly caused by autoimmune diseases such as Hashimoto's thyroiditis, which leads to thyroid tissue destruction.