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
(1)Of all the misfortunes a child can suffer, few provoke as much dread as autism. The condition—a neurological disorder that im
(1)Of all the misfortunes a child can suffer, few provoke as much dread as autism. The condition—a neurological disorder that im
admin
2016-11-03
15
问题
(1)Of all the misfortunes a child can suffer, few provoke as much dread as autism. The condition—a neurological disorder that impedes language and derails social and emotional development—has become ever more common in recent decades, thanks partly to better diagnosis. Experts now suspect that one person in 160 lives with some degree of autism; that’s three to four times the rate in the 1970s. But while the outward manifestations are well known, science is just beginning to illuminate the underlying biology. What goes wrong in the autistic brain? What defect or injury leaves it largely incapable of empathy? A growing body of evidence, capped by new findings from the University of California, San Diego, raises a tantalizing possibility. The new study, published in The Journal of the American Medical Association, links the condition to abnormally rapid brain growth during infancy—and it raises new hopes for diagnosis and treatment.
(2)The key to last weeks finding was not a milhon-dollar imaging device but a tape measure. Past studies have shown that autistic toddlers have abnormally large brains for their age. But because autism is rarely detected in kids younger than 2 or 3 years old, researchers have never known quite how that situation arises. Two years ago the San Diego team realized that children’s old medical records might hold important clues. Led by neuroscientist Eric Courchesne, the researchers tracked down early-childhood head measurements for 48 autistic preschoolers, and compared them with national norms. As it turned out, the kids’ heads had been smaller than average at birth but had grown explosively during infancy, shooting from the 25th percentile to the 84th in roughly a year’s time. And faster growth predicted greater impairment. Mildly autistic subjects reached only the 59th percentile, but the severely afflicted kids reached the 95th percentile.
(3)The implications are hard to miss. Autism, the new findings suggest, is not a sudden calamity that strikes children at the age of 2 or 3 but a developmental problem that can be traced back to infancy. That alone should help allay the suspicion that autism is caused by vaccines or pollutants that kids encounter later in childhood But the new findings say less about the causes of autism than about its dynamics. The current study focuses on the first year of life, but the trouble isn’t confined to that period. Other recent studies suggest that the early growth spurt is followed by several years of slower expansion, giving the autistic child an adult-size brain by me age of 4 or 5. During adolescence and adulthood, autistic brains are generally no larger than normal ones. Unfortunately, they exhibit a range of other anomalies, including dense clusters of underdeveloped cells in the hippocampus and amygdala-structures that are critical for integrating emotional and sensory information.
(4)Does rapid growth actually cause all this damage? It’s still an open question. "The abnormal growth patterns give you a clue that something is amiss," says Dr. Margaret Bauman, a neurologist at Harvard Medical School and the LADDERS Autism Research Foundation, "but we can only guess at the underlying process." Courchesne believes it can be summed up in three words: "growth without guidance". Normal brain development is not a monologue but a dialogue, in which the brain generates neural circuits and the child’s experiences determine which ones survive. The first year of life is a critical period for this "experience-guided growth" and it’s not hard to see how a sudden shift into high gear might derail it. The brains circuitry would expand haphazardly as cell growth outpaced experience, creating a chronic sensory overload. Courchesne hopes researchers will now confirm the dangers of unregulated brain growth by inducing it experimentally in animals. "Once we know what causes this growth defect," he says, "it may be possible to use biological treatments to counter it."
(5)The more immediate goal is simply to recognize autism at earlier stages, and to give affected kids the support they need to grow and learn and cope. Will the new findings advance that cause? Dr. Janet Lainhart, an autism expert at the University of Utah, is skeptical. The findings... are most useful to researchers attempting to define the underlying developmental neuropathology of autism, she writes in a commentary on the San Diego study, rather than to physicians trying to identify young children with autism. That’s because rapid head growth can signal other childhood maladies, including tumors and hydrocephalus, and often means nothing at all. Lainhart calculates that if doctors used head circumference as a screening test for autism, they would pick up 60 healthy children for every autistic one. Courchesne concedes the point, but he still believes it’s prudent for pediatricians to monitor head growth. The world’s oldest measurement tool still has the power to amaze, he says. It may not provide a definitive diagnosis, but it is inexpensive, non-invasive and objective and most of the concerns it raises can quickly be resolved. Where autism is concerned, that’s still as good a goal as any.
The previous study of autism has shown the following EXCEPT that _____.
选项
A、autistic children have extraordinarily large brains
B、children’s medical records might contain useful information
C、biological treatment could be applied to cure autism
D、we can guess some information from abnormal growth pattern
答案
C
解析
文章全篇讨论关于新发现的问题,没有关于自闭症生物疗法的描述;而且第1段也指出揭示自闭症生物学内涵才刚刚起步。因此,选C。第2段第2句提到,患自闭症刚学走路的小孩的头大得与其年龄不相称,故排除A;第2段第4句提到,儿童过去的医学记录可能包含重要线索,故排除B;第4段第3句鲍曼博士指出,异常生长模式提示我们某个东西出了错,但只是猜测内在变化过程,故排除D。
转载请注明原文地址:https://kaotiyun.com/show/RS7O777K
0
专业英语八级
相关试题推荐
Therearetwomethodsoffighting,theonebylaw,theotherbyforce;thefirstmethodisthatofmen,thesecondofbeasts;an
Thefirstmoderndigitalcomputersweredevelopedinthe1940sformilitarypurposesthataroseduringWorldWarII.Thesecomp
Hewasanundersizedlittleman,withaheadtoobigforhisbody—asicklylittleman.Hisnerveswerebad.Hehadskintroubl
MarkTwain’smasterwork______—hasfatheredmodernAmericanliterature.
GeorgeBernardShaw’s______isacommentaryonIbsen’sdramaticworksandalsoservedastheauthor’sownprogramofdramaticc
大自然对人的恩赐,无论贫富,一律平等。所以人们对于大自然,全都一致并深深地依赖着。尤其在乡间,上千年来人们一直以不变的方式生活着。种植庄稼和葡萄,酿酒和饮酒,喂牛和挤奶,锄草和栽花;在周末去教堂祈祷和做礼拜,在节日到广场拉琴、跳舞和唱歌;往日的田园依旧是今
A、Potatoes.B、Eggyolk.C、Cereals.D、Tea.B本题考查重要细节。根据句(9)可知,鸡蛋、蛋黄和大豆都能创造通道帮助大脑吸收营养和排除毒素,所以说它们很重要,每天都需要吃,因此[B]为答案。
A、Allyearlong.B、Atthebeginningoftheyear.C、Attheendoftheyear.D、Inthemiddleoftheyear.B本题考查换工作的好时机。访谈中主持人问女士是否
A、Music.B、Sportgames.C、Interests.D、Socialchanges.A在访谈结束时,主持人说到,下一次节目我们会谈论美国的艺术、写作和建筑。A项的内容符合艺术范畴,故为答案。其他选项在此次节目中已被谈论。
A、Qualified.B、Questionable.C、Unsuitable.D、Apathetic.A本题设题点在观点态度处。根据句(7)可知,面试者认为求职者表现得非常好,正是他们想要的人,因此[A]为正确答案。
随机试题
"InonlysixdaysIlostsevenpoundsofweight.""Twofullinchesinthefirstthreedays!"Thesearethekindsofst
简述文学艺术类旅游资源的开发原则与开发措施。
丹痧的主要病机是
男,40岁。感冒后,下唇及唇周皮肤出现成簇的针头大小的小水疱,破溃后结痂,局部灼痒、疼痛。该患者患的疾病为
结构中含有吡啶基的药物为结构中含有噻唑基的药物为
A.红细胞膜上含A凝集原,血清中含抗A凝集素B.红细胞膜上含B凝集原,血清中含抗B凝集素C.红细胞膜上含A凝集原,血清中含抗B凝集素D.红细胞膜上含B凝集原,血清中含抗A凝集素E.红细胞膜上同时含有A和B两种凝集原,血清中无凝集素A型血为(
使用三因素分析法分析固定制造费用差异时,固定制造费用的效率差异反映()。
若函数y=与y=x—1的图像的交点坐标为(a,b),则的值为________.
下列不属于紧缩性货币政策的措施是()
(2016年多选47)下列行为中,构成侵犯商标权的有()。
最新回复
(
0
)