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
2025-02-22
8
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] In the passage, the author is primarily concerned with
选项
A、presenting a hypothesis and describing compelling evidence in support of it
B、raising a question and describing an important discovery that led to an answer
C、showing that a certain autoimmune disease cannot yet be treated effectively with drugs
D、explaining what evidence exists for an autoimmune cause for narcolepsy
E、discussing the importance of research on animals for the study of human disease
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3968052.html
相关试题推荐
Almostallrecognizethatnon-scientistsaswellaslaymenareinterestedinsci
Scientistshave______foryearsthatturbulencewithinthegaseouscloudsfound
CENSORSHIP:INFORMATION::A、exemplification:standardB、quarantine:diseaseC
Diseaseisafluidconceptinfluencedbysocietalandculturalatti
Diseaseisafluidconceptinfluencedbysocietalandculturalatti
Diseaseisafluidconceptinfluencedbysocietalandculturalatti
Diseaseisafluidconceptinfluencedbysocietalandculturalatti
Diseaseisafluidconceptinfluencedbysocietalandculturalatti
Scientistsresearchinghypnosishaveuncoveredevidencethatcounte
Scientistsresearchinghypnosishaveuncoveredevidencethatcounte
随机试题
Theenergycrisis,whichisbeingfeltaroundtheworld,hasdramatizedhow
Anartisthopesthatthepublicwill______.[br]Thewritersaysthatcontempor
"MadeinChina"lostitsnovelty(新颖)longago.Thelabelhasbecome【C1】______
[originaltext]ThenorthernItaliancityisslowlydrowning—sealevelsint
住宅燃气系统设计,以下不正确的是( )。A.十层及十层以上住宅内不得使用瓶装液
某企业有关职工工资的时间数列数据如表6—3所示。 对该企业的工资总
股息增长模型有( )。 Ⅰ.零增长模型 Ⅱ.负增长模型 Ⅲ.不变增长模型
患者,男,26岁,晚餐后踢足球时突发上腹部阵发性绞痛1小时,呕吐30分钟入院。入
道路危险货物运输管理工作的主要内容包括( )和危险货物运输管理。A.危险货物货源
2015年1月1日,小李与位于S市的某单位签订劳动合同。约定日薪200元,合同期
最新回复
(
0
)