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Unit 93 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; 10/27/2003, p47； 1. What is implied in the first paragraph? [A]Some people regard it as a tragic failure. 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 3. Zhuang's attitude toward the critics' conclusion is one of __________. [A]reserved consent 4. The only difference existing between nuclear-transfer and cloning technique is ________. [A]whether it is used for research or for helping the infertile 5. The text intends to express the idea that _________. [A]research of cloning has potential risks 答案：CABDC 篇章剖析 本文采用提出问题——分析问题的模式，指出细胞核移植和克隆技术上存在的伦理方面的争议以及研究人员本人对此事的看法。在第一段指出人们对一项新成果的不同看法；第二段指出这一技术对一名中国不孕妇女的帮助；第三段指出细胞核移植和克隆技术的区别以及都存在的危险性；第四段和第五段指出研究人员的一些做法和看法。 词汇注释 ethical[5eWIk（E）l]adj.与伦理有关, 民族的, 民族特有的 难句突破 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）. 主体句式：…concern over potential risks is why … 结构分析：“a process”在句子中的语法成分是同位语；后面又跟了一个“that”引导的定语从句；在从句中又使用了“so…that”句式；在从句中又使用了“where”引导的从句。 句子译文：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——这是一套令葛瑞佛觉得太过于烦琐而终止了这一技术的研究工作，并将其转给了中国研究人员的程序。这项研究工作后来在中国也被禁止（在本月才刚被禁止，这是发生在庄的病人怀孕后很久以后的事了）。 题目分析 １.答案为C,属推理判断题。做好本题的关键是对“depending on whom you ask”的理解。对于不同的人来说，他们对实验的反应也不相同。 ２.答案为A,属推理判断题。原文对应信息“critics have suggested that cloning and nuclear transfer are equally risky for humans”。文中提到的“多莉”羊和一名中国孕妇分别是为了进一步具体说明克隆和细胞核移植技术及其存在的一些危险。 1． 答案为B，属情感态度题。原文对应信息是“．．．an assertion Zhuang rejects”。“reject” 这个词比较正式，也表达较强的感情色彩。 ４.答案为D，属事实细节题。原文对应信息是“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.” 5.答案为C，属中心思想题。有关克隆技术的研究，从研究角度来说无可厚非，但是从伦理学角度来说争议不小。 参考译文 上周在德克萨斯医学会议上宣布了一项实验。对于不同的询问对象，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。 所有这些观点都有各自的道理。中国医生采用一种新技术来帮助一位农妇怀孕，其动机很明显是治疗不孕症。跟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，使用由纽约大学的詹姆士·葛瑞佛博士和广东中山医科大学的庄广伦博士发明的技术，可以把病人的受精卵取出来，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，细胞发育正常进行。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。 使一些医生和伦理学家感到心烦的是，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。把这种实验用于人体，从伦理学的角度来说，很多人都对此感到反感。此外，由于我们无法搞懂的原因，克隆动物通常会自行流产，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（为了提高其它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。“产科产生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实验中的每一个环节有任何关系。”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——这是一套令葛瑞佛觉得太过于烦琐而终止了这一技术的研究工作，并将其转给了中国研究人员的程序。这项研究工作后来在中国也被禁止（在本月才刚被禁止，这是发生在庄的病人怀孕后很久以后的事了）。 评论家认为所做的结论是：尽管是出于其它目的而进行研究的，但是完善可能会用做人类克隆的技术不是一个好主意——这项声明是庄极力反对的。“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。我们也需要它。” |
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