2.Since the start of the deadly AIDS epidemic in the 1980s,scientists have been working towards a cure.Now,they may be close to finding one.
Researchers have developed a method to cut the viral (病毒) DNA from a person's infected cells.It is called CRISPR/Cas9and it means the person could be virus-free.
DNA is a substance that carries genetic information in the cells of animals and plants.
This gene-editing took place in a scientific lab,but has not been tested on humans yet.
"It's a big step,"said Kamel Khalili,Ph.D.He is lead researcher and chair at the Department of Neuroscience at Temple University in Philadelphia,Pennsylvania.He and his team made the discovery.
But more tests have to be done to know if it will be a cure for the millions of patients infected with the HIV virus,which causes AIDS.
Antiretroviral drugs have been doing a good job of keeping the AIDS virus from reproducing.Such a good job that levels of HIV are just about undetectable in infected people who take the medicine.
But even with the drugs,the virus stays in the body's"T-cells,"which are T-lymphocytes.AIDS damages the immune system,hurting the body's ability to fight off disease.
So the drugs are kind of a"Band-Aid solution,"Khalili explained.They keep the virus from growing.But they do not remove the memory of the virus from the cells.
And,the moment antiretroviral drugs are stopped,the HIV comes back to life and begins making more HIV,which is the AIDS virus.
Khalili and his team of scientists appear to have found a way to cut this viral DNA from infected people's cells.
In their lab,they took cells from people infected with the HIV virus.They removed the part of the cell that was holding the virus.
He said they had"in some cases,near 90percent of the virus replication (復(fù)制) or production dropped in the patient samples after treatment in the laboratory."
Khalili and his team have not actually cured any patients yet.However,he believes this gene-editing technology could possibly cure AIDS.
"Removal of the virus can lead to the cure."He said,"it's an exciting time,and the reason is the technologies are available and the methods are in place and our knowledge has increased."
"And hopefully,there will be funding to take us toward this exciting moment for developing the cure strategy by getting rid of viral DNA using editing techniques."
62.The newly found way is intended to cure AIDS byB.
A.doing damage to the immune system
B.removing viral DNA from infected cells
C.doing research into antiretroviral drugs
D.taking cells from those infected with the HIV virus
63.What can we know about antiretroviral drugs from the passage?C
A.They are likely to make more AIDS virus.
B.They can help body to fight against disease.
C.They are unable to cure people of their HIV virus.
D.Virus will disappear from T-cells because of them.
64.Kamel Khalili's words in the last two paragraphs indicate thatD.
A.his new method is bound to be a perfect cure for AIDS
B.a(chǎn)ntiretroviral drugs will be dropped in the near future
C.their discovery has made great contributions to human beings
D.they will succeed curing AIDS if they aren't lacking in money.
分析 本文講述了自從上世紀90年代艾滋病爆發(fā)以來,科學(xué)家已經(jīng)在尋找治療艾滋病的方法,現(xiàn)在終于有了新的突破研究人員發(fā)現(xiàn)一種新的方法,能夠阻止艾滋病病毒DNA在人體細胞內(nèi)繼續(xù)復(fù)制,這種方法叫做CRISPR/Cas9.盡管這種方法還沒有治愈任何人,但科學(xué)家想象不久的將來可以攻克艾滋病這一難題.
解答 BCD
62.B 根據(jù)Researchers have developed a method to cut the viral (病毒) DNA from a person's infected cells.可知,新的方法是把患者感染細胞內(nèi)的病毒DNA去除,故選B
63.C 根據(jù)They keep the virus from growing.But they do not remove the memory of the virus from the cells.可知antiretroviral drugs不能完全治愈艾滋病患者,故選C
64.D 根據(jù)And hopefully,there will be funding to take us toward this exciting moment for developing the cure strategy by getting rid of viral DNA using editing techniques."如果不缺少資金的資助,他們對早日戰(zhàn)勝艾滋病毒充滿了信心,故選D
點評 本文是新聞題材,關(guān)注此類文章的特征:新聞的主題往往在第一段,最后常常有總結(jié)的段落.中間部分是對新聞細節(jié)的展開說明.所以在閱讀時要關(guān)注首段和尾端,把握主旨;解題時要關(guān)注中間的細節(jié),根據(jù)題干和選項中的關(guān)鍵詞或句定位細節(jié),比對選項和文章細節(jié)確定答案.