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
考研
The time-enduring metaphor of the war on cancer, as overused as it may be, is as evocative as ever to describe our efforts to be
The time-enduring metaphor of the war on cancer, as overused as it may be, is as evocative as ever to describe our efforts to be
admin
2019-08-01
36
问题
The time-enduring metaphor of the war on cancer, as overused as it may be, is as evocative as ever to describe our efforts to beat the disease that will claim nearly 566,000 American lives this year alone. So let’s fall back on martial imagery to describe our current position: We now know the enemy far better than ever before. And that promises much more precise targets.
【R1】______ But mounting discoveries about the astoundingly complex essence of cancer—that its causes lie in multitudes of genes gone awry—are also pointing the way toward treatments aimed in laser-like fashion at a patient’s unique set of genetic limitations. In mid-October, scientists reported in Nature that they’ve identified 26 key mutated genes linked to lung cancer, for example.
【R2】______Yet until quite recently, the only tools available—the blunt-force mainstays of surgery, chemotherapy, and radiation—treated everyone much the same. Then, in the 1990s, powerful new computing technology allowed researchers to begin comparing the DNA of cancerous and healthy tissues and gain a look at the very blueprints of similar-looking but markedly different tumors.
【R3】______It seems that many of the abnormal genes operate together to create trouble in a smaller number of distinct cellular pathways—the molecular processes that make a cancer cell so deadly. These common pathways are the likely drug targets. Think of it this way: Multiple cars are taking separate routes to the same garage, and instead of trying to stop each car on the road, you block the driveway. The pathways are shared by cancers in different organs; the new lung cancer study, for example, revealed mutations also fingered in cancer of the retina and colon, among others, suggesting that drugs can be used against a panoply of tumors.
【R4】______Theoretically, that means drugs could be much better matched to patients. That kind of matching is only occasionally available now. Lung cancer drugs Tarceva and Iressa target the cell-growth receptor EGFR; for reasons not yet fully understood but most likely involving mutations in EGFR, they work better in some patients than in others.
【R5】______For one thing, finding all the mutations linked to a certain cancer isn’t enough. How and why are genes turned on and off? And how do the signaling pathways affect and influence each other? Even when a target is identified as important and a drug made to block it, chances are the tumor has another way to reach the same end—or will find one as it continues to grow and mutate, which explains why people develop resistance to targeted therapies that work at first.
What this all suggests, many say, is that just as HIV is now managed by a drug cocktail, cancer may one day be handled as a chronic disease controlled by a changing mix of several drugs at once in sequence or combination. The race is on to expand the arsenal. According to a recent Datamonitor report, 10 new targeted drugs have entered the marketplace since 2005, and researchers are studying existing therapies to see if they’re more effective together.
[A]It’s been clear for years, for example, that cancers vary widely even if they look the same under a microscope: Some are slow growing, others are aggressive; some patients respond to one drug, while others are not helped at all.
[B]Devising treatments to combat every single mutation would be a huge task—but that may not be necessary, experts say.
[C]Of course, as even Sun Tzu recognized, intel must be translated into effective action, and in this struggle, that effort has been all too plagued by failure.
[D]Within just a few years, the technology may be available to sequence an individual tumor’s genes and find out exactly what pathways need blocking, says Raymond DuBois, dean of M. D. Anderson Cancer Center in Houston and president of the American Association for Cancer Research.
[E]A new study has found that mutations in either of two genes are involved in the development of lung cancer.
[F]Studies have found that the epidermal growth factor receptor(EGFR)gene is mutated in many non-smallcell lung cancers and that these mutations are associated with increased sensitivity to gefitinib(Iressa)or erlotinib(Tarceva), tyrosine kinase(TK)inhibitors that target EGFR.
[G]Clearly, converting this mass of new genetic information into perfectly tailored therapies isn’t a quick and dirty exercise.
【R1】
选项
答案
C
解析
作者在前文介绍了我们现在对癌症的了解比以前已经多了很多,而且就已知的情况我们将会有更明确的抗癌目标。那么接下来该把目标付诸实际行动。七个选项中只有[C]具体提到了必须转化为有效的行动。因此[C]是正确答案。
转载请注明原文地址:https://kaotiyun.com/show/AI2Z777K
0
考研英语一
相关试题推荐
ThepastfiveyearshavebeenabadtimetobeataxpayerinEurope.Acrossthecontinent,governmentshavereliedheavilyonta
Poets,songwritersandpoliticianshatetheidea,butfordecadesopinion-pollevidencehasbeenclear;moneybuyshappinessand
TheBigMacindexisbuiltontheideaofpurchasing-powerparity,thetheorythatinthelongruncurrencieswillconvergeunti
Retrofittinghousestouselessenergyshouldbeano-brainerforhomeowners.【C1】______time,moneyspentonwaystoreduceheat
Anysufficientlyadvancedtechnology,notedArthurC.Clarke,aBritishscience-fictionwriter,isindistinguishablefrommagic.
Theshortergrowingseasonsexpectedwithclimatechangeoverthenext40yearswillendangerhundredsofmillionsofalreadypo
Theshortergrowingseasonsexpectedwithclimatechangeoverthenext40yearswillendangerhundredsofmillionsofalreadypo
BankruptcyratesintheU.S.havebeengrowingformorethantwodecadesdespitegenerallyrisinglevelsofpersonalincome.The
Hewaspunished______heshouldmakethesamemistakeagain.
随机试题
检验者自收到样品之日起,对一般食品和对中毒食品(包括可疑中毒食品),应分别在几天内出具检验报告
预归类申请人对多项商品申请约束性预归类的,应根据一项商品一份预归类申请书的原则分别提出。()
资产评估机构申请证券评估资格,最近3年评估业务收人合计不少于2000万元,且每年不少于300万元。()
物业管理项目一般采用()方式。
团体督导的优点有( )。
某寺院有50个和尚,某月寺院主持发现,当月有15人挑过水,有19人砍过柴,既没挑过水也没砍过柴的有21人。那么既挑过水也砍过柴的有多少人?()
设g(x)=∫0xf(u)du,其中f(x)=则g(x)在(0,2)内().
下图是责任链设计模式的类图,该设计模式的目的是________。该图中,Handler和Handler之间是关联关系,Handler和ConcreteHandler之间是继承关系。
传统密码体制所用的加密密钥和解密密钥(),也称为()体制。
JeanleftAliceSpringsonMondaymorningwithregret,andflewalldayina"Dragonfly"aircraft(anditwasaveryinstructiv
最新回复
(
0
)