Category: D

A dilation of the membranes that line the lumbosacral spine, typically seen in patients with Marfan’s syndrome.  

A noninvasive test for coronary artery disease in which dobutamine is given to patients to increase the workload of the heart, and then the heart is evaluated with ultrasonic imaging. Regions of the heart that do not receive adequate blood flow (ischemic regions) contract poorly during the stress of the test but normally when the…

Silica containing fossilized shells of microscopic algae with a siliceous or calcium-containing cell wall. It is used in insulating material and filters and as an absorbent.  

Imperfect formation of spermatozoa.  

Defective nutrition caused by disease of the nervous system.  

Diseases of muscle, such as Duchenne or Becker muscular dystrophy, that result from deficiencies or abnormalities of dystrophin.  

Imperfect development and function of the thyroid gland.  

Failure of the embryonic neural tube to close during development. This is a cause of anencephaly, spina bifida, and meningocele.  

Uncoordinated contractions of muscle fibers (e.g., of the myocardium or of the urinary bladder when the external urinary sphincter is closed).  

Any disorder in the normal or expected coordination of timed events.