共用题干
Parkinson's Disease
cells in the brain. Normally , these nerve cells make an important chemical called dopamine（多巴胺）.
Dopamine sends signals to the part of your brain that controls movement.It lets your muscles move smoothly
and do what you want them to do.When you have Parkinson's,these nerve cells break down.Then you no
longer have enough dopamine,and you have trouble moving the way you want to.research to look for the answer. They are studying many possible causes,including aging and poisons in the
environment.Abnormal genes seem to lead to Parkinson's disease in some people.But so far,there is not
enough proof to show that it is always inherited.disease,although not everyone has it.Tremor often starts in just one arm or leg or only on one side of the
body.It may be worse when you are awake but not moving the affected arm or leg.It may get better when you
move the limb or when you are asleep.In time,Parkinson's affects muscles all through your body,so it can
lead to problems like trouble swallowing or constipation（便秘）.In the later stages of the disease,a person
with Parkinson's may have a fixed or blank expression,trouble" speaking,and other problems.Some people
also have a decrease in mental skills.can control the symptoms and make the disease easier to live with.You may not even need treatment if your
symptoms are mild.Your doctor may wait to prescribe medicines until your symptoms start to get in the way of
your daily life.Your doctor will adjust your medicines as your symptoms get worse.You may need to take
several medicines to get the best results.