A 15-year-old boy is evaluated by a clinician for failure to develop normal male secondary sexual characteristics. Physical examination reveals small testes, a small penis, and gynecomastia. The boy has had some difficulties in school, and the parents say that the school psychometrist said he had an IQ of 90. This patient's condition is most likely to be related to which of the following?
Maintenance of the corpus luteum during the first trimester of pregnancy is accomplished principally by the secretion of
A 52-year-old female presents with groin pain . Physical examination reveals a bulge in the groin area immediately inferior to the inguinal canal. The physician suspects that the patient has a femoral hernia containing a loop of small intestine. Which of the following structures is located immediately medial to the hernia sac?
The modified structures at the border of
the epithelium shown above are immotile in a 23-year-old patient. Which of
the following would be a consequence of this lack of motility?
A patient with tuberculosis develops bright orange-red urine and calls his physician in a panic because he is afraid he is bleeding into the urine. The patient has no other urinary tract symptoms. Which of the following medications is most likely to produce this side effect?
Which of the following Starling force changes is the primary cause of the edema seen in patients with nephrotic syndrome?
A 32-year-old, blood type A positive male receives a kidney transplant from a blood type B positive female donor with whom he had a 6-antigen HLA match. Once the kidney is anastomosed to the man's vasculature, the transplant team immediately begins to observe swelling and interstitial hemorrhage. After the surgery, the patient developed fever and leukocytosis and produced no urine. Which of the following is the most likely explanation?
A cardiovascular physiologist is
performing experiments using a new alpha1 adrenergic agonist to determine the
amount of vasoconstriction the new drug can produce compared with a
phenylephrine control. Which of the labeled structures is the cellular target
of both of these drugs?
An 80-year-old woman dies after a long history of progressive memory loss, apraxia, and recurrent episodes of confusion. In the last months of life she was bedridden and unable to recognize familiar faces and objects. The pathologist identifies numerous flame-shaped intracytoplasmic inclusions in neurons of the neocortex and hippocampus. These consist of paired helical filaments (PHFs) on electron microscopy. Which of the following biochemical changes most likely accounts for the development of PHFs in this condition?
A 71-year-old man has been in excellent health, and practicing competently as an attorney. He is brought to the emergency room following a motor vehicle accident. A workup, including imaging of the spine, thorax, and head, is negative, but the patient is admitted for overnight observation. His injuries include several lacerations to the face and extremities as well as several contusions to the thorax. Three weeks later, he is admitted to the hospital for confusion. A neurologic exam is normal except that he is not oriented to time or place, and can recall only 1 out of 6 objects after 3 minutes. Which of the following is the most likely diagnosis?