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
Scientists say they have high hopes for a drug that could one day provide a new form of treatment for HIV-AIDS. A compound, whic
Scientists say they have high hopes for a drug that could one day provide a new form of treatment for HIV-AIDS. A compound, whic
admin
2010-08-21
57
问题
Scientists say they have high hopes for a drug that could one day provide a new form of treatment for HIV-AIDS. A compound, which interferes with an elusive protein used by the HIV virus to infect human cells, has worked extremely well in monkeys. If the drug proves effective in human trials, scientists say, it could bolster (加强) the effectiveness of two existing AIDS drugs, particularly in fighting drug-resistant strains of the virus.
Researchers at the pharmaceutical (制药的) company Merck are very excited about an experimental drug, which has worked as well in monkeys infected with a primate version of the virus as any of the existing, anti-AIDS drugs.
It works by blocking one of three proteins, or enzymes, the HIV virus uses to gain entrance into and infect human immune system cells.
Inhibitor drugs have been developed to block two of the proteins, to slow progression of the disease after infection. They have become standard therapy as a "cocktail" for people infected with HIV
Those enzymes are reverse transcriptase (转录酶) and protease (蛋白酶). The first converts the virus’ genetic material into that of its host cells. The second chops up the resulting larger proteins into smaller pieces, producing smaller viral particles that infect new cells.
The third prong of cellular attack is a protein called integrase (整合酶), which experts say has been harder to block. Once HIV fools host cells by changing its genetic information so it can enter them. integrase acts like a cut and paste operation in a word processor, deleting on immune cell’s genetic material and replacing it with its own.
An integrase inhibitor would give doctors a third line of attack against HIV infection, according to virologist Daria Hazuda of the division of Virus and Cell Biology at Merck.
"This would offer a third class of anti-retroviral medications that can be combined with reverse transcriptase inhibitors and pretense inhibitors. And since it is a new mechanism of action, these compounds are active against multi-drug resistant variants. So variants that are resistant to all current therapies have been selected in HIV-patients," she said.
Current anti-AIDS drugs eventually become resistant to therapy, or stop working, because the virus changes its shape.
While researchers are encouraged by the success with the compound’s effectiveness in monkey trials, developing a drug that is equally effective in humans can be difficult.
Steven Young is executive director of the Department of Medicinal Chemistry at Merck. He says, if scientists find a compound that is equally effective in people, the company would ask U.S. regulators to speed approval of the drug.
"Yeah, I really think that’s what we’re hoping for." he said. "I mean. we need to get data that show it has robust anti-viral effects in people. And if we’re able to get that data. I think we would petition for fast track status."
Dr. Young says an integrase inhibitor has the potential to prevent drug resistance.
"To ensure our best chances of preventing resistance, we would give this as part of a cocktail therapy," he added. "And I think it’s really our plan that we would test this with reverse transcriptase inhibitors and pretense inhibitors, as well."
While integrase deletes an immune cell’s genetic material and replaces it with its own, it acts like ______ in a word processor.
选项
答案
a cut and paste operation
解析
根据题干中的关键词word processor定位到第六段第二句,可知HIV病毒一旦通过改变自身的遗传信息而诱导宿主细胞并进入其中,它就像文字处理软件中的剪切和粘贴程序一样,删除免疫细胞的遗传信息,并替换为自己的遗传信息。
转载请注明原文地址:https://kaotiyun.com/show/o87K777K
0
大学英语六级
相关试题推荐
A、Yes,shewill.B、Shehasnotmadeherdecisionyet.C、No,shewon’t.D、Itisnotknown.D本题问“Lillian会来参加聚会吗”。文中提到因为Bob行事从来难以
OnesummermywifeChrisandIwereinvitedbyfriendstorowdowntheColoradoRiverinaboat.Ourexpeditionincludedmanyhi
WhatSelectivityMeansforYouUnderstandingAdmissionFactorsCollegeadmissionofficersacrossmostofthenationrepo
WhatSelectivityMeansforYouUnderstandingAdmissionFactorsCollegeadmissionofficersacrossmostofthenationrepo
A、Thewomanblamesthemanforhisabsence.B、Thewomanthinksthateverythingwasallright.C、Thewomanthanksthemanforhis
A、Becauseit’sshining.B、Becauseit’srare.C、Becauseit’sexpensive.D、Becauseitcamefromancienttimes.DA、B、C三个选项都是文中提到的其
Mostscientistsspendtheirtimeinlaboratories______(称称量量、用各和海洋生物做实验).
Stonetools,animalbonesandanincisedmammothtuskfoundinRussia’sfrigidfarnorthhaveprovidedwhatarchaeologistssayi
Websterdefinesadviceasbeing"arecommendationwithregardtoacourseofaction".Theexpression,"Ineedsomeadvice"h
随机试题
生长激素与下列哪种激素有协同作用
成人体内氨的最主要代谢去路为
生物膜的功能越复杂,其组成中含量越多的是
工程竣工验收时对工程总体质量的确认应符合工程质量总目标,其验收标准具体表现为工程设计文件、()和工程质量验收标准。
招股说明书全文文本书脊应标明()字样。
由于生产资料和劳动产品的私有制,商品生产者的劳动直接表现为()。
positivebehindresultA.afraidtheircountrieswillbeleft【T7】______B.Whatwaslessvisiblethen,however,werethenew,【
刑罚只能由()代表国家适用。
移动互联网的迅速普及除了归功于网络宽带的增加之外,还与丰富的应用有密不可分的关系。()技术使得Web应用不仅丰富,而且能够实现高度的互动,极大地改善了移动互联网用户的体验。
Wereadthenewspaperseverydaytokeep______currentevents.
最新回复
(
0
)