[不定项选择题]共用题干 Multiple Sclerosis（多发性硬化症）

1 Multiple Sclerosis ( MS) is a disease in which the patient ' s immune（免疫的）system attacks the
central nervous system.This can lead to numerous physical and mental symptoms,as the disease affects the
transmission of electrical signals between the body and the brain.However,the human body,being a
flexible,adaptable system,can compensate for some level of damage,so a person with MS can look and feel
fine even though the disease is present.
2 MS patients can have one of two main varieties of the disease:the relapsing form（复发型）and the
primary progressive form.In the relapsing form,the disease progresses in a series of jumps;at times it is in
remission（减轻）,which meatis that a person's normal functions return for a period of time before the system
goes into relapse and the disease again becomes more active.This is the most common form of MS;80％～90%
of people have this form of the disease when they are first diagnosed.The relapse一remission cycle can
continue for many years.Eventually,however,loss of physical and cognitive functions starts to take place
and the remissions become less frequent.
3 In the primary progressive form of MS,there are no remissions and a continual but steady loss of
physical and cognitive functions takes place. This condition affects about 10%～15% of sufferers at diagnosis.
4 The expected course of the disease,or prognosis（预后）,depends on many variables:the subtype of
the disease,the patient's individual characteristics and the initial symptoms.Life expectancy of patients,
however,is often nearly the same as that of an unaffected person一provided that a reasonable standard of
care is received.In some cases a near一normal life span is possible.
5 The cause of the disease is unclear ; it seems that some people have a genetic susceptibility（易感
性）,which is triggered by some unknown environmental factor. Onset（发作）of the disease usually occurs in
young adults between the age of 20 and 40.It is more common in women than men;however,it has also
been diagnosed in young children and in elderly people. Young adults might have a higher chance of developing the disease than________.
A.relatives of MS patients
B.the elderly people
C.the disease
D.the primary progressive form
E.the brain
F.life expectancy