首页
登录
职称英语
Some scientists have concluded that narcolepsy, a disease which dis
Some scientists have concluded that narcolepsy, a disease which dis
游客
2024-01-11
30
管理
问题
Some scientists have concluded that narcolepsy, a disease which disrupts
sleep patterns, arises when unknown agents in the environment spur an
autoimmune reaction winding up damaging neurons in the brain circuits that Line
control arousal and muscle tone. Honda found that all members of a group of
(5) narcoleptics had one aspect of their tissue type in common, one of the human
leukocyte antigens (HLAs). Whereas the HLA type was clearly not sufficient to
induce narcolepsy, Honda’s finding indicated that HLA type greatly affected
susceptibility to the disease. HLA molecules are pitchfork-shaped structures that
cells of the body use to show pieces of the proteins they contain to the immune
(10) system, which ordinarily attacks foreign substances and cells infected by
viruses.
Evidence for an autoimmune cause of narcolepsy will most likely come from
studies of the brains of people who had the disorder. Ever since Gineau
correctly named narcolepsy as a distinct syndrome in 1880, researchers have
(15) examined the brains of patients in a futile search for neurological damage that
could explain the symptoms of the disease. Mignot observed that the brains of
narcoleptic dogs had more than the usual number of receptors for the
neurotransmitters acetylcholine, dopamine and norepinephrine and higher levels
of some of the neurotransmitters themselves, changes identical to those Aldrich
(20) later noted human narcoleptic brains.
Given that narcolepsy is not progressive but chronic—i.e. after the
establishment of symptoms, narcoleptics do not deteriorate or improve-
pathologists may have been focusing their efforts on the wrong stage of the
disease’s progression. This suggested that the damage might occur during a
(25) short time, roughly during the period in which a patient first develops signs of
the illness. Debris left over from degenerative processes that occurred at the
age of 20 would be removed by the brain’s support cells long before most
patients died, and any remaining clues would be obscured by the normal
degeneration of aging. As a loss of neurons would be undetectable unless the
(30) dead cells were concentrated in a particular area, as in Parkinson’s disease, or
unless many neurons died, as in Alzheimer’s disease, I therefore examined the
brains of narcoleptic dogs shortly after their symptoms had begun, and found
clear evidence that neurons in certain areas of the dogs’ brains were
degenerating between one and two months of age, just before and during the
(35) onset of symptoms. Evidence of the degeneration largely disappeared by the
time the dogs were six months old. At this moment, all we can give patients are
drugs to treat narcolepsy’s symptoms, even though this research promises the
definite potential of a cure. [br] It may be inferred from the passage that by studying the brains of narcoleptic dogs, the author learned that
选项
A、neural degeneration may occur too early for scientists to be able draw many useful conclusions about it
B、a loss of neurons would be undetectable unless the dead cells were concentrated in a particular area of the brain
C、pathologists not only were researching the wrong stage of the disease process, but ignoring its unique effects on different species
D、the brain tends through its natural processing to remove the effects of neural degeneration
E、the theories of Aldrich and Mignot were largely correct, at least as far as dogs are concerned
答案
A
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3353493.html
相关试题推荐
A、neuraldegenerationmayoccurtooearlyforscientiststobeabledrawmanyus
Althoughscientistshavelong______thehumanappendixas______organ,therei
A、Scientistshaveruledoutthepossibilitythattheappendixisinvolvedinhin
CENSORSHIP:INFORMATION::A、exemplification:standardB、quarantine:diseaseC、bene
Althoughsomescientists______thecredibilityoftheworkoftheirassistants,
Scientistshavelongsoughtthereasonsfortherelativelyyoungageof
Scientistshave______foryearsthatturbulencewithinthegaseouscloudsfound
A、ofteninhumaneandrarelynecessaryB、unrelatedtotheactualstudyofdisease
Diseaseisafluidconceptinfluencedbysocietalandculturalattitudes
Like______,ArcticscientistssequesteredonthePolemustaccustomthemselvest
随机试题
Thereareplentyofstudieswhichshowthatdogsactassocialcatalysts(催化
AWorldWithoutTimeorNumberThePirahciareanisolated
以下关于抵押率的确定表述正确的有()。A.信贷人员应根据抵押物的评估现值,分析其
房地产经纪人员社会及心理方面的知识主要包括()等方面的知识。A.房地产市场营
新修订《药品管理法》开始实施的日期是A.2002年1月1日 B.2002年12
A.治疗指数 B.内在活性 C.效价 D.安全指数 E.亲和力决定药物是
共用题干 患儿,12岁。身高130cm,体重20kg,入院诊断吉兰-巴雷综合征
因为科技进步,越来越重视天气预报,我国气象观测卫星是()。A.天空系列气象卫星
按照净现值法,贷款价值的确定主要依据对未来()的贴现值。 A.现金流入B
按照我国保险制度,建安工程一切险()。A.由承包人担保 B.包含执业责任
最新回复
(
0
)