首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Some scientists have concluded that narcolepsy, a disease which disrupts sleep patterns, arises when unknown agents in th
Some scientists have concluded that narcolepsy, a disease which disrupts sleep patterns, arises when unknown agents in th
admin
2011-01-17
24
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.
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://kaotiyun.com/show/rhjO777K
本试题收录于:
GRE VERBAL题库GRE分类
0
GRE VERBAL
GRE
相关试题推荐
Wesubstitutefish______meatseveraltimesaweek.
Thenoticewaswritteninseverallanguages______foreigntouristsshouldmisunderstandit.
Icannot______thetruthofyourwords,althoughtheygoagainstmyinterests.
Listeningtoloudmusicatrockconcerts______causedhearinglossinsometeenagers.
Mistakesarethethingsthatnobodywants,butwestillmakemistakesatanyage.Somemistakeswemakeareaboutmoney.Somear
IfkSnisdefinedtobetheproductof(n+k)(n-k+1)forallpositiveintegerskandn,whichofthefollowingexpressions
Proteinsynthesisbeginswhenthegeneencodingaproteinisactivated.Thegene’ssequenceofnucleotidesistranscribedinto
JosephGlatthaar’sForgedinBattleisnotthefirstexcellentstudyofBlacksoldiersandtheirWhiteofficersintheCivilWar
Aftersuffering$2billioninlossesand25,000layoffs,thenation’ssemiconductorindustry,whichmakeschipsthatruneveryth
CarolinaHospitalnotesthatCuban-AmericanwriterswhowriteprimarilyinEnglisharedismissedfromanthologiesandanalyseso
随机试题
当归四逆汤所治厥逆的病机是
根据现行国家标准《建筑设计防火规范》(GB50016),关于疏散走道设置的说法,错误的有()。
A.维生素AB.维生素D2C.维生素D1D.维生素B2E.维生素B6
黄某和张某共同贩卖毒品,黄某被当场抓获并拘留,张某住逃。有关部门的下列哪一做法是正确的?()
工程施工过程中应当采取消防安全措施,下列说法中错误的是()。
安全事故发生后,现场有关单位和人员不得破坏事故现场、毁灭相关证据。有()原因时,需要移动事故现场物件的,应当做出标志,绘制现场简图并做出书面记录,妥善保存现场重要痕迹、物证。
固定资产盘亏,应先转入“待处理资产损溢”账户,批准处理后根据具体原因分别转入“管理费用”、“营业外支出”等账户。()
新保单的初始佣金有不同的表现形式,常用的形式包括( )。Ⅰ.每1000元保额支付A元佣金Ⅱ.首年度保费的B%Ⅲ.首年度保费的C%,且不超过每1000元保额支付D美元的总额Ⅳ.首年度保费的E%加上F元Ⅴ.趸缴保费的G%
单位安排职工到会议室听报告。如果每3人坐一条长椅,那么剩下48人没有坐;如果每5人坐一条长椅,则刚好空出两条长椅。听报告的职工有多少人?()
在一项集体比赛中,你带领的队伍进入了复赛。在比赛前你听到队员聊天。认为团队人员安排不合理。还有关于你的毫无根据的花边新闻。请问作为队长你该怎么办?
最新回复
(
0
)