Parkinson's disease:A slowlyprogressiveneurologicdiseasethat is characterized by a fixed inexpressive face, tremor atrest,减缓的voluntarymovements,gaitwith short accelerating steps, peculiarpostureandmuscleweakness (caused by degeneration of an area of thebraincalled thebasal ganglia), and low production of theneurotransmitterdopamine. Most patients are over 50, but at least 10 percent are under 40. Treatment involves use ofmedication, such as levodopa (brand name: Larodopa) andcarbidopa(brand name:Sinemet). A surgical procedure known as deep brain stimulation,inwhich externally controlled electrodes are implanted into the brain, has also been shown to be helpful. There are nobloodorlaboratorytests to diagnose thecondition. Although it is achronicand progressive disease, the degree of disability varies among affected persons. Also known asparalysisagitans and shakingpalsy.
