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
Jonas Frisen had’ his eureka moment in 1997. Back then, scientists suspected that there was a special type of cell in the brain
Jonas Frisen had’ his eureka moment in 1997. Back then, scientists suspected that there was a special type of cell in the brain
admin
2011-02-11
20
问题
Jonas Frisen had’ his eureka moment in 1997. Back then, scientists suspected that there was a special type of cell in the brain that had the power to give rise to new brain cells. If they could harness these so-called neural stem cells to regenerate damaged brain tissue, they might someday find a cure for such brain diseases as Alzheimer’s and Parkinson’s. But first they had to figure out where neural stem cells were and what they looked like. Frisen, then a freshly minted Ph. D. at the Karolinska Institute in Stockholm, was peering through his microscope at some tissue taken from a rat’s injured spinal cord when he saw cells that appeared to have been enervated by the injury, as though they were busy making repairs. Frisen thought these might be the neural stem cells scientists had been looking for. It took him six years of painstaking research to make sure.
Frisen is quick to emphasize that his research is basic and that treatments are years off. But the findings so far hint at extraordinary potential. Two years ago he identified neural stem cells in the adult human brain. And he’s now researching the mechanisms by which these cells grow into different types of brain cells. Rather than growing brain tissue in a petri-dish and implanting it in, say, the forebrain of a Parkinson’s patient, doctors might someday stimulate the spontaneous growth of new neural cells merely by administering a drug. "It sounds like science fiction," Frisen says, "but we can already do it in mice." In 2007 he will publish the results of his recent experiments. He’s isolated a protein in the mouse brain that inhibits the generation of nerve cells. Using other chemicals, he’s been able to block the action of this inhibitor, which in turn leads to the production of new brain cells.
Frisen honed his analytical mind at the dinner table in Goteborg, in southwest Sweden. His mother was a mathematics professor and his father was an ophthalmologist. Frisen went to medical school intending to be a brain surgeon or perhaps a psychiatrist, but ended up spending all his free time in the lab. In 1998 he got seed money from a Swedish venture capitalist to set up his own company, NeuroNova, to commercialize his work. A private foundation tried to lure him to Texas, but Swedish businessman Marcus Storch persuaded him to stay by funding a 15-year professorship at Karolinska, eovering his salary and the running costs of his 15-person lab. "Jonas Frisen stood out from all candidates by far," says Storch, whose Tobias Foundation sponsors stem-cell research. "He is something of a king in Sweden." Two years ago two more venture capitalists helped the company expand by hiring a CEO and setting up a separate lab.
Since most researchers are interested in stem cells taken from embryos, the practice has attracted considerable controversy in the past few years. Frisen has benefited indirectly from research restrictions in the United States, which have driven funds and brain-power to Singapore, the United Kingdom and Sweden. The Bush Administration currently forbids U. S. -funded work on all but 78 approved stem-cell cultures, many of which are located outside the country. In just one sign of the times, the U. S. -based Juvenile Diabetes Research Foundation recently announced grants totaling $ 20 million for stem-cell research—the largest award yet given to the field by a medical charity—to research institutes in Sweden and elsewhere, but not in the United States.
Since Frisen doesn’t work with embryonic stem cells, he’s unwittingly become a champion of the radical fight, which argues that scientists ought to concentrate solely on adult stem ceils. He happens to disagree. "It would be overoptimistic or outright stupid," he says. "To really understand adult cells, we need to master how embryonic stem cells work." But what really gets Frisen going is when people ask him when they can expect a drug for Parkinson’s and other diseases. "I say, five decades, just to get the number thing out of the way," he quips. "I’m not going to oversell this." When pressed, he admits that clinical trials might begin in five years. That would be a eureka moment worth waiting for.
The word "enervated" in the first paragraph probably means
选项
A、weakened.
B、demolished.
C、vitalized.
D、enlivened.
答案
A
解析
语义题。由题干定位至首段。倒数第三句提到:...he saw cells that appeared to have been enervated by the injury,as though they were busy making repairs.由句中的injury和making repairs可知细胞受到伤害,C“有生命力的”和D“有生气的”不符合文意,排除。B意为“彻底破坏的”,句中只是提到injury,并未指出情况严重,B程度过重。A“虚弱的”符合上下文语境,故为答案。
转载请注明原文地址:https://kaotiyun.com/show/YmYO777K
0
专业英语八级
相关试题推荐
Whethertheeyesarethewindowsofthesoulisdebatable,thattheyareintenselyimportantininterpersonalcommunicationisa
Theperiodrangingfrom1865to1914hasbeenreferredtoas______inAmericanliterature.
ExpositionExpositioniswritingthatexplains.Mostofthebooksinuniversityli-brariesareexamplesofexposition.Alth
WhenGermanyinvadedPoland,BritainandFrancedeclaredwaronGermany.ThentheU.S【1】______indebate.
TheChamberlain’sMen,inShakespeare’stime,werearemarkablegroupofpeople-excellent______whowerealsobusinesspartners
A、Rome’sLaRepublicB、theFrench-languageSwissdaily24HeuresC、aRussiandailyD、BritishtabloidtheDailyMirrorB
DanishpolicehavebeenleftscratchingtheirheadsastheyhuntforthevandalswhodecapitatedtheLittleMermaid.Fewclue
A、InthesouthernstateofTumailimo.B、IntheminingtownofTnmailimo.C、InthejunglessoutheastofCaracas.D、70kilometers
A、commons.B、farmers.C、aristocrats.D、workers.C
爬山虎总是野心勃勃地企图占领每一寸墙。在那无数枝卷向上的藤蔓中,有一枝几乎攀上了那尖尖的屋顶,这时有一阵风刮来,把它悬在半空中。刘川从窗口望出去,看到了对面墙上的这个镜头,下意识地笑了起来。“你是藤,我是墙。”有一天他对小梅说。
随机试题
降低营养液的pH值可用________进行调解。
滴定管可用于精确量取溶液体积。()
【2005年真题】根据我国现行规定,更新改造项目的分类标准是()。
根据支付结算法律制度的规定,下列有关汇兑的表述中,不正确的是()。
管理会计报告与一般对外财务报告相比较,其特征有()。
在教育工作中谨记“欲速则不达”的道理,即教育工作要遵循人身心发展的()规律。
在一次酒宴中,怎样在维护领导颜面的前提下为领导代酒?
抗日民族统一战线正式形成的标志是
有以下程序#include<stdio.h>intfun(inta,intb)main(){if(b==0)returna;{printf("%d\n",fun(4,2)
A、Elegantbodyposture.B、Properspeech.C、Neatappearance.D、Goodmanners.C题干考查男士认为面试官作出判断的最重要依据是什么。对话中,男士说他认为他们应当着装整洁、适当,他们的着
最新回复
(
0
)