考研英语 学英语,练听力,上听力课堂! 注册 登录
> 考研英语 > 考研英语阅读 >  内容

《考研英语阅读理解100篇 基础版》第7章 医药类 Unit 93

所属教程:考研英语阅读

浏览:

2019年01月24日

手机版
扫描二维码方便学习和分享
 
Depending on whom you ask,the experiment announced at a Texas medical conference last week was a potential breakthrough for infertile women,a tragic failure or a dangerous step closer to the nightmare scenario of human cloning.  
There's truth to all these points of view.Infertility was clearly the motivation when Chinese doctors used a new technique to help one of their countrywomen get pregnant.Unlike some infertile women,the 30-year-old patient produced eggs just fine,and those eggs could be fertilized by sperm.But they never developed properly,largely because of defects in parts of the egg outside the fertilized nucleus.So using a technique developed by Dr.James Grifo at New York University,Dr.Zhuang Guanglun of Sun Yat-sen University in Guangzhou took the patient's fertilized egg,scooped out the chromosome-bearing nuclear material and put it in a donated egg whose nucleus had been removed.In this more benign environment,development proceeded normally,and the woman became pregnant with triplets who carried a mix of her DNA and her husband’s—pretty much like any normal baby.  
What has some doctors and ethicists upset is that this so-called nuclear-transfer technique has also been used to produce clones,starting with Dolly the sheep.The only significant difference is that with cloning,the inserted nucleus comes from a single,usually adult,cell,and the resulting offspring is genetically identical to the parent.Doing that with humans is ethically repugnant to many.Besides,for reasons that aren’t yet well understood,cloned animals often abort spontaneously or are born with defects; Dolly died very young,though she had seemed healthy.And because the Chinese woman's twins were born prematurely and died(the third triplet was removed early on to improve chances for the remaining two),critics have suggested that cloning and nuclear transfer are equally risky for humans.  
Not likely,says Grifo.“The obstetric outcome was a disaster,” he admits,“but the embryos were chromosomally normal.We have no evidence that it had anything to do with the procedure.” Even so,concern over potential risks is why the Food and Drug Administration created a stringent approval process for such research in 2001—a process that Grifo found so onerous that he stopped working on the technique and gave it to the researchers in China,where it was subsequently banned (but only this month,long after Zhuang's patient became pregnant).  
The bottom line,say critics,is that perfecting a technique that could be used for human cloning,even if it were developed for another purpose,is just a bad idea—an assertion Zhuang rejects.“I agree that it makes sense to control these experiments,” he says.“But we’ve developed an effective technology to help people.We understand how to do it.We need it.”  
注(1):本文选自Time;  
注(2):本文习题命题模仿对象为2003年真题Text 4。  
1.What is implied in the first paragraph?  
A) Some people regard it as a tragic failure.  
B) The new experiment means a breakthrough for some people.  
C) People have different reactions to the new experiment.  
D) The new experiment means a step further to the dangerous human cloning.  
2.The author uses the case of Dolly and the Chinese pregnant woman to show that ______.  
A) both nuclear-transfer and cloning are dangerous for humans and animals  
B) both of them benefit from the new technique  
C) both of them are the examples of technical failure  
D) both of them are the fruits of the new technology  
3.Zhuang's attitude toward the critics’ conclusion is one of ______.  
A) reserved consent  
B) strong disapproval  
C) slight contempt  
D) enthusiastic support  
4.The only difference existing between nuclear-transfer and cloning technique is ______.  
A) whether it is used for research or for helping the infertile  
B) whether the offspring looks like the parent  
C) whether it is used in animals or human beings  
D) whether the inserted nucleus comes from a single and usually adult cell  
5.The text intends to express the idea that ______.  
A) research of cloning has potential risks  
B) the research of cloning should be stopped totally  
C) ethics and research of cloning are in contradiction  
D) researchers should have the right to continue the study of cloning  
 
上周在得克萨斯医学会议上宣布了一项实验。对于不同的人,实验的意义也不相同。对于不孕妇女来说这是一种潜在的突破;对某些人来说这是一种悲剧性的失败,或者是朝人类无性繁殖的噩梦般的境地又迈出了危险的一步。  
这些观点都有各自的道理。中国医生采用一种新技术帮助一位农妇怀孕,其目的很明显是治疗不孕症。与一些不孕妇女不同的是,这位三十岁的病人可以排出健康的卵细胞,并且那些卵细胞可以跟精子结合成受精卵。但是这些卵细胞却不能正常发育,其原因主要是受精核外部的部分卵细胞有缺陷。因此,使用纽约大学詹姆士·葛瑞佛博士和广东中山医科大学庄广伦博士发明的技术,可以把病人的受精卵取出来,然后提取带有染色体的核物质,并把它放入已经去除核子的别人捐赠的卵细胞内。在这种更为有利的环境中,细胞可以正常发育。这位妇女怀上了三胞胎,胎儿携带着她和她丈夫两人的DNA——这跟其他正常的婴儿没什么大的差别。  
令一些医生和伦理学家感到不安的是,这项所谓的细胞核移植技术被用于克隆,多莉羊就是这一技术最开始的产物。其中最大的不同之处仅在于在克隆过程中,嵌入的细胞核来自单细胞,通常又是成熟的细胞。从遗传上来说,这样产生的后代同母体是一样的。把这种实验用于人类,从伦理学的角度来说,很多人都反对。此外,我们还有些问题仍没有搞清楚其原因,如克隆动物经常会自动流产,或者具有天生缺陷。多莉尽管看起来很健康,但是她很早就死了。因为那位中国妇女早产下双胞胎,并且都未能保住性命(为了提高其他两个胎儿的存活几率,第三个胎儿早就被做掉了),所以评论家认为克隆和细胞核移植对于人类来说都是同等危险的。  
葛瑞佛认为事情并不一定是这样。“产科出现这样的后果真是一场灾难,”他承认说,“但是从染色体来看,这些胚胎都是正常的。我们没有证据显示这跟移植过程有任何关系。” 尽管如此,由于担心潜在的危险,美国食品药物管理局2001年就类似研究制定了较为严格的批准程序——这套程序令葛瑞佛觉得过于烦琐而终止了这一技术的研究工作,并将其转交给了中国研究人员。这项研究工作后来在中国也被禁(本月刚刚被禁止,这是发生在庄的病人怀孕后很久以后的事了)。  
评论家认为,尽管是出于其他目的而进行研究的,但是研究成果进一步完善以后可能会用做人类克隆的技术,这就是个坏主意——这项声明是庄博士极力反对的。“我赞同控制这些实验确实有一定的意义,”他说,“但是我们已经发明了这项可以帮助人的有效的技术。我们知道该如何使用,也需要它。”  
用户搜索

疯狂英语 英语语法 新概念英语 走遍美国 四级听力 英语音标 英语入门 发音 美语 四级 新东方 七年级 赖世雄 zero是什么意思广州市天顺跃居英语学习交流群

  • 频道推荐
  • |
  • 全站推荐
  • 推荐下载
  • 网站推荐