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
"I have great confidence that by the end of the decade we’ll know in vast detail how cancer cells arise," says microbiologist Ro
"I have great confidence that by the end of the decade we’ll know in vast detail how cancer cells arise," says microbiologist Ro
admin
2017-07-31
52
问题
"I have great confidence that by the end of the decade we’ll know in vast detail how cancer cells arise," says microbiologist Robert Weinberg, an expert on cancer. "But," he cautions, "some people have the idea that once one understands the causes, the cure will rapidly follow. Consider Pasteur, he discovered the causes of many kinds of infections, but it was fifty or sixty years before cures were available."
This year, 50 percent of the 910,000 people who suffer from cancer will survive at least five years. In the year 2000 , the National Cancer Institute estimates, that figure will be 75 percent.
For some skin cancers, the five-year survival rate is as high as 90 percent. But other survival statistics are still discouraging — 13 percent for lung cancer, and 2 percent for cancer of the pancreas.
With as many as 120 varieties in existence, discovering how cancer works is not easy. The researchers made great progress in the early 1970s, when they discovered that oncogenes, which are cancer-causing genes, are inactive in normal cells. Anything from cosmic rays to radiation to diet may activate a dormant oncogene, but how remains unknown. If several oncogenes are driven into action, the cell, unable to turn them off, becomes cancerous.
The exact mechanisms involved are still mysterious, but the likelihood that many cancers are initiated at the level of genes suggests that we will never prevent all cancers. "Changes are a normal part of the evolutionary process," says oncologist William Hayward. Environmental factors can never be totally eliminated; as Hayward points out, "We can’t prepare a medicine against cosmic rays."
The prospects for cure, though still distant, are brighter.
"First, we need to understand how the normal cell controls itself. Second, we have to determine whether there are a limited number of genes in cells which are always responsible for at least part of the trouble. If we can understand how cancer works, we can counteract its action."
The example of Pasteur in the passage is used to______.
选项
A、predict that the secret of cancer will be disclosed in a decade
B、indicate that the prospects for curing cancer are bright
C、prove that cancer will be cured in fifty to sixty years
D、warn that there is still a long way to go before cancer can be conquered
答案
D
解析
从第1段最后一句话“想一想Pasteur吧,他发现了许多传染病病因,但是过了五六十年才有了治疗方法”可知,D项为正确答案。
转载请注明原文地址:https://kaotiyun.com/show/YeFO777K
0
考博英语
相关试题推荐
democracyimaginationdifferentflexibilityovercomeonlineoffertraditionalmodern
democracyimaginationdifferentflexibilityovercomeonlineoffertraditionalmodern
Insuchachanging,complexsocietyformerlysimplesolutionstoinformationalneedsbecomecomplicated.Manyoflife’sproblems
Thecurrentfederalfundsinterestrateofonly1.75percenthasclearlybecomeunsustainableinviewoftheeconomy’sresilien
Thirty-onemillionAmericansareover60yearsofage,andtwenty-ninemillionofthemarehealthy,busy,productivecitizens.By
Atthefall2001SocialScienceHistoryAssociationconventioninChicago,theCrimeandJusticenetworksponsoredaforumonth
Doyouagreeordisagreewiththefollowingstatement?Peopleneversatisfiedwithwhattheyhave.Theyalwayswantsomethin
OnehundredboatsbearingonemilliondesperateuninvitedimmigrantssetsailfromtheGanges(恒河)forthefabledcoastoftheFre
Inrecentyears,manyAmericansofbothsexesandvariousageshavebecomeinterestedinimprovingtheirbodies.Theyhavebecom
随机试题
给定程序MODll.C中函数fun的功能是:判断一个整数是否是素数,若是返回1,否则返回0。在main()数中,若fun返回1输出YES,若fun返回0输出NO!。请改正程序中的错误,使它能得出正确的结果。注意:不要改动main函数。不得增行
下面有关罗伊适应模式的内容哪些是正确的( )。
患者,男性.18岁。因车祸致头部受伤,当即昏迷5小时,格拉斯哥昏迷评分为6分。患者目前的表现符合
下列关于导爆索起爆的规定正确的是()。
安装双层石膏板时,面层板与基层板的接缝应(),并不得在同一根龙骨上接缝。
SDH设备的抖动测试项目包括()。
历史长河中,明朝的那些事儿在专家的唇舌之问,如莲花般绽放。弹指的光阴______中,那些虚虚实实的历史悬疑让学者们______。填入划横线部分最恰当的一项是:
从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性。
有三个关系R、S和T如下:则由关系R和S得到关系T的操作是
搜索考生文件夹中的AUTXIAN.BAT文件,然后将其删除。
最新回复
(
0
)