VOA标准英语2013--Discovery Could Lead to New Drugs to Block Deadly Viruses
时间：2019-01-14 作者：英语课 分类：VOA标准英语2013年(三月)
Discovery Could Lead to New Drugs to Block Deadly Viruses
Viruses are strange things. Though there is some scientific question about whether viruses are alive or not, they do have a basic genetic 1 structure that allows them to be biologically active. But they don't have the built-in reproductive capacity of bacteria -- tiny, living organisms which, once they have infected a human host, can make copies of themselves using their own DNA 2.
John Connor, a virologist at Boston University in Massachusetts, explains that in order for viruses to reproduce and become a disease threat, they must first hijack 3 the genetic machinery 4 of a living cell:
“They’re parasites," said Connor. "They get inside our cells and use a lot of our machinery in order to make extra copies of themselves. And so that poses a really delicate question of how do you destroy the virus without getting yourself.”
Connor and his colleagues screened thousands of chemical compounds, looking for ones that showed strong antiviral activity.
They identified several small molecules 6 that interfere 7 with the replication of a class of pathogens known as NNS viruses, which cause the deadly Marburg and Ebola infections, as well as measles 8 and mumps 9.
Once they have invaded a host cell, NNS viruses use their own genetic molecule 5 -- known as RNA -- to hijack the host cell's DNA and force it to make copies of the virus.
The most effective compounds discovered by the Boston researchers shut down that replication process -- at least in cell-culture experiments -- by limiting the viruses' RNA production.
The compounds do not thwart 10 all viruses -- they have no effect, for example, on HIV, the virus that causes AIDS -- because of differences in the way viral pathogens enter and commandeer cells.
Just as antibiotics 11 are effective against many bacterial 12 illnesses, Connor says he hopes this discovery leads to the development of broad-spectrum antiviral drugs to treat a variety of currently incurable 13 viral infections.
“Basically, one of the things my lab is interested in is trying to find 'monkey wrenches 14' [disruptive agents] to throw into viral replication machinery so it doesn’t work anymore," said Connor. "And the idea there is, if we find good ways of keeping viruses from doing their basic replication, we can ideally develop a new drug to treat these viruses.”
An article by Boston University’s John Connor and colleagues on the discovery of compounds to combat Ebola, Marburg and other viral infections is published in the journal Chemistry and Biology.
- It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
- Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。
- DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
- Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。
- Most countries refuse to give sanctuary to people who hijack aeroplanes.大多数国家拒绝对劫机者提供庇护。
- The hijack take place just after the plane take off.劫持是飞机刚起飞后发生的。
- Has the machinery been put up ready for the broadcast?广播器材安装完毕了吗？
- Machinery ought to be well maintained all the time.机器应该随时注意维护。
- A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
- This gives us the structural formula of the molecule.这种方式给出了分子的结构式。
- The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
- Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。
- If we interfere, it may do more harm than good.如果我们干预的话，可能弊多利少。
- When others interfere in the affair,it always makes troubles. 别人一卷入这一事件，棘手的事情就来了。
- The doctor is quite definite about Tom having measles.医生十分肯定汤姆得了麻疹。
- The doctor told her to watch out for symptoms of measles.医生叫她注意麻疹出现的症状。
- Sarah got mumps from her brother.萨拉的弟弟患腮腺炎，传染给她了。
- I was told not go near Charles. He is sickening for mumps.别人告诉我不要走近查尔斯， 他染上了流行性腮腺炎。
- We must thwart his malevolent schemes.我们决不能让他的恶毒阴谋得逞。
- I don't think that will thwart our purposes.我认为那不会使我们的目的受到挫折。
- the discovery of antibiotics in the 20th century 20世纪抗生素的发现
- The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。
- Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
- Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。
- All three babies were born with an incurable heart condition.三个婴儿都有不可治瘉的先天性心脏病。
- He has an incurable and widespread nepotism.他们有不可救药的，到处蔓延的裙带主义。