USMLE

Which of the following drugs used in the treatment of noninsulin-dependent diabetes mellitus (NIDDM) has no effect on the secretion of insulin?

A child who has had abnormal development of the membranous bones has a broad skull with associated facial and dental anomalies. Which other bones are most likely to also be affected?

The blood from an 8-year-old boy was analyzed by flow cytometry . The exact number of B cells was counted. Which of the following cell surface markers was likely used to identify the B cells in this blood sample?

A thyroid mass usually moves with swallowing because the thyroid gland is enclosed by which of the following fascia?

Damage to which of the following structures might produce hair cell loss?

The cell in the center of the electron micrograph above is important in wound healing and plays a role in the pathological process underlying Dupuytren's contracture. Which of the following cell types is depicted?

During a routine physical examination of a 74-year-old man, a physician palpates a large, pulsating mass in the lower abdomen. To which of the following is this mass most likely etiologically related?

A 43-year-old man is brought to the general medicine clinic by his wife. She states that his memory has progressively deteriorated over the last several years, and that his personality has been changing. On examination, the physician notes abnormal, writhing movements of the man's limbs and hyperreactive patellar reflexes. An MRI of the head reveals a loss of volume in the neostriatum and cortex. A family history reveals that similar symptoms occurred in several members of the patient's family. Which of the following genetic mechanisms has been implicated in this disorder?

While lying supine in bed eating, a child aspirates a peanut. Which of the following bronchopulmonary segments would this foreign object mos t likely enter?

A 35-year-old retarded man with a strong history of mental retardation among male relatives undergoes genetic testing. His lymphocytes are cultured in a medium containing methotrexate and 4% of the metaphase chromosomes in the lymphocytes show a breakpoint at q27.3 on the X chromosome. This man is at increased risk for which of the following cardiovascular disorders?