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
55
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] The passage supplies information to answer which of the following questions?
选项
A、Which species, human or dog, has greater numbers of the neurotransmitters that have been hypothetically linked to narcolepsy?
B、At what age do human beings first experience the degenerative effects of narcolepsy?
C、What role do human leukocyte antigens perform for the human immune system?
D、Why did Honda initially suspect that HLAs played a role in narcolepsy?
E、Which of the researchers named in the passage isolated narcolepsy as a distinct syndrome?
答案
C
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3353492.html
相关试题推荐
Scientistshavesuggestedthatonceevery10millionyearsorsoatrulycolossa
ThevisitingpharmacologistsconcludedthatthepresentamalgamofChineseandW
Scientistshaverecentlydiscoveredwhatcouldbethelargestandoldestliving
Scientistshaveobservedlargeconcentrationsofheavy-metaldepositsintheupp
Scientistscalculatedthattheasteroid,travelingat46,000milesanhour,iso
Coronaryangiography,asophisticatedmethodfordiagnosingcoronarydiseaseinv
Increasingly,historiansareblamingdiseasesimportedfromtheOldWorldfo
Increasingly,historiansareblamingdiseasesimportedfromtheOldWorldfo
Generallyscientistsentertheirfieldwiththegoalofdoingimportantnewrese
Thispassageisexcerptedfrommaterialpublishedin1997.Scientistshavebeen
随机试题
"PhysicalandChemicalPropertiesandChanges"→Sugar,water
Whatistheminimumnumberofmatchesyoucanremovefromthisdiagramtoleave
Completethenotesbelow.WriteONEWORDONLYforeachanswer.Thesleepylizard
某公司董事会议明确了公司应从以下三个方面强化控制措施:一是实施全面预算管理,将各
A.656.58 B.629 C.705.69 D.728.57
男性,28岁,黏液脓血便2年,伴里急后重感,查体:一般状态佳,左下腹轻度压痛应补
作为风险防范的第一道关口,在贷款的派生收益与贷款本身安全性的权衡上,公司信贷业务
机体感受邪气后,病邪在机体内潜伏一段时间,或在诱因的作用下,过时而发病,这称为A
(2021年上半年真题)晓军向老师报告:“安安偷看我的试卷。”老师说:“安安怎么
职业道德建设是先进性与广泛性的统一,其要求是( )。A.倡导“先进”,但要给
最新回复
(
0
)