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大学英语综合教程第三册 15

所属教程:大学英语综合教程第三册

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[00:00.00] Cloning offers the possibility of making exact copies of ourselves.

[00:05.30]Should this be allowed? What benefits and dangers may cloning bring?

[00:10.92]A CLONE IS BORN By Gina Kolata

[00:15.62]On July 5, 1996, at 5:00 p.m., the most famous lamb in history entered the world.

[00:23.64]She was born in a shed,

[00:26.28]just down the road from the Roslin Institute in Roslin, Scotland,

[00:31.74]where she was created. And yet her creator,

[00:36.52]Ian Wilmut, a quiet, balding fifty-two-year-old embryologist, does not remember

[00:44.07]where he was when he heard that the lamb,named Dolly, was born.

[00:49.84]He does not even recall getting a telephone call from John Bracken, a scientist

[00:56.50]who had monitored the pregnancy of the sheep that gave birth to Dolly,

[01:02.09]saying that Dolly was alive and healthy and weighed 6.6 kilograms.

[01:09.04]2 No one broke open champagne. No one took pictures.

[01:14.21]Only a few staff members from the institute and a local veterinarian

[01:20.27]who attended the birth were present.

[01:23.59]Yet Dolly, who looked for all the world like hundreds of other lambs

[01:29.31]that dot the rolling hills of Scotland,was soon to change the world.

[01:35.37]3 When the time comes to write the history of your age, this quiet birth,

[01:41.51]the creation of this little lamb,will stand out.

[01:46.11]The world is a different place now that she is born.

[01:50.58]4 Dolly is a clone. She was created not out of the union of a sperm and an egg

[01:58.07]but out of the genetic material from an udder cell of a six-year-old sheep.

[02:04.42]Wilmut fused the udder cell with an egg from another sheep,

[02:09.59]after first removing all genetic material from the egg.

[02:14.87]The udder cell’s genes took up residence in the egg

[02:19.23]and directed it to grow and develop. The result was Dolly,

[02:25.14]the identical twin of the original sheep that provided the udder cells,

[02:30.99]but an identical twin born six years later.

[02:36.21]5 Until Dolly entered the world, cloning was the stuff of science fiction.

[02:41.80]It had been raised as a possibility decades ago,then dismissed,

[02:47.68]something that serious scientists thought was simply not going to happen anytime soon.

[02:53.92]Now it is not fantasy to think that someday, perhaps decades from now,

[03:00.19]but someday, you could clone yourself and make tens,dozens,

[03:06.38]hundreds of genetically identical twins.

[03:10.62]Nor is it science fiction to think that your cells could be improved beforehand,

[03:17.15]genetically engineered to add some genes and remove others.

[03:22.53]6 True, it was a sheep that was cloned, not a human being.

[03:28.12]But there was nothing exceptional about sheep.

[03:31.96]Even Wilmut, who made it clear that he was opposed to the very idea of cloning people,

[03:38.54]said that there was no longer any theoretical reason

[03:43.24]why humans could not clone themselves, using the same methods

[03:48.78]he had used to clone Dolly.

[03:51.71]“There is no reason in principle why you couldn’t do it.”

[03:56.15]But, he added, “All of us would find that offensive.”

[04:00.85]7 We live in a time when we argue about pragmatism and compromises

[04:06.65]in our quest to be morally right.

[04:09.97]But cloning forces us back to the most basic questions that have plagued humanity

[04:16.31]since the dawn of recorded time:

[04:19.79]What is good and what is evil?And how much potential for evil can we tolerate

[04:27.86]to obtain something that might be good?

[04:31.57]Cloning, with its possibilities for creating our own identical twins,

[04:37.24]brings us back to the ancient sins of vanity and pride;

[04:42.36]the sins of Narcissus, who so loved himself, and of Prometheus, who, in stealing fire,

[04:51.21]sought the powers of God.So before we can ask

[04:56.57]why we are so fascinated by cloning, we have to examine our souls and ask,

[05:03.26]What exactly so bothers many of us

[05:07.38]about trying to make an exact copy of our genetic selves?

[05:12.92]Or, if we are not bothered, why aren’t we?

[05:17.68]8 We want children who resemble us. Even couples who use donor eggs or donor sperm,

[05:25.33]search catalogs of donors to find people who resemble themselves.

[05:31.13]Several years ago, a poem by Linda Pastan,

[05:35.96]called “To a Daughter Leaving Home,”

[05:39.67]was displayed on the walls of New York subways. It read:

[05:45.52]Is it my own image I love so In your face? I lean over your sleep,

[05:53.31]Narcissus over His clear pool, ready to fall in , to drown for you

[06:00.23]if necessary.

[06:02.58]Yet if we so love ourselves, reflected in our children,

[06:07.99]why is it so terrifying to so many of us to

[06:12.35]think of seeing our exact genetic replicas born again,

[06:17.50]identical twins years younger than we?

[06:21.81]Is it one thing for nature to form us through a genetic lottery,

[06:27.16]and another for us to take complete control, abandoning all thoughts of somehow,

[06:33.80]through the mixing of genes,

[06:36.75]having a child who is like us, but better? Normally, when a man and a woman have a child together,

[06:46.02]the child is an unpredictable mixture of the two. We recognize that, of course, in the old joke

[06:54.04]in which a beautiful but dumb woman suggests to an ugly but brilliant man that the two have a child.

[07:01.83]Just think of how wonderful the baby would be, the woman says, with my looks and your brains.

[07:09.19]Aha, says the man. But that is the child inherited my looks and your brains?

[07:16.69]9 Cloning brings us face-to-face with what it means to be human and makes us confront both

[07:24.03]the privileges and limitations of life itself. It also forces us to question the powers of science.

[07:32.78]Is there, in fact, knowledge that we do not want? Are there paths we would rather not pursue?

[07:42.08]10 The time is long past when we can speak of the purity of science, divorced from its consequences.

[07:49.89]If any needed reminding that the innocence of scientists was lost long ago,

[07:56.37]they need only recall the comments of J.Robert Oppenheimer,the genius who was a father of the atomic bomb

[08:05.09]and who was transformed in the process from a supremely confident man, ready to follow his scientific curiosity,

[08:14.16]to a humbled and troubled soul, wondering what science had let loose.

[08:20.58]11Before the bomb was made, Oppenheimer said,

[08:24.58]“When you see something that is technically sweet you go ahead and do it.”

[08:30.46]After the bomb was dropped on Hiroshima and Nagasaki, in a chilling speech delivered in 1947, he said:

[08:39.65]“The physicists have known sin; and this is a knowledge which they cannot lose.”

[08:46.79]12 As with the atom bomb, cloning is complex, multi-layered in its threats and its promises.

[08:54.39]It offers the possibility of real scientific advances that can improve our lives and save them. In medicine,

[09:04.05]scientists dream of using cloning to reprogram cells so we can make our own body parts for transplantation.

[09:13.77]Suppose,for example, you needed a bone marrow transplant.

[09:18.97]Some deadly forms of leukemia can be cured completely

[09:24.43]if doctors destroy your own marrow and replace it with healthy marrow from someone else.

[09:31.74]But the marrow must be a close genetic match to your own. If not, it will lash out at you and kill you.

[09:40.47]Bone marrow is the source of the white blood cells of the immune system. If you have someone else’s marrow,

[09:49.01]you’ll make their white blood cells. And if those cells think you are different from them, they will attack.

[09:57.34]13 But suppose, instead, that scientists could take one of your cells—any cell—and merge it with a human egg.

[10:06.51]The egg would start to divide, to develop, but it would not be permitted to divide more than a few times.

[10:15.13]Instead, technicians would bathe it in proteins that direct primitive cells, embryo cells, to become marrow cells.

[10:26.05]What started out to be a clone of you could grow into a batch of your marrow—the perfect match.

[10:34.38]14 More difficult, but not inconceivable, would be to grow solid organs, like kidneys or livers, in the same way.

[10:44.31]15Another possibility is to create animals whose organs are perfect genetic matches for humans.If you need a liver,

[10:53.92]a kidney, or even a heart, you might be able to get one from a specially designed pig clone.

[11:01.68]16 The possibilities are limitless, scientists say, and so, some argue,

[11:07.74]we should stop focusing on our hypothetical fears and think about the benefits that cloning could bring.

[11:16.44]clone lamb balding embryologist

[11:22.49]克隆 羊羔 开始秃顶的 胚胎学家

[11:28.54]pregnancy give birth to champagne veterinarian

[11:34.82]怀孕 产生 香槟酒 兽医

[11:41.10]for all the world dot creation union

[11:46.65]在各个方面 散步于 创造物 结合

[11:52.20]sperm udder cell fuse

[11:58.67]精子 乳房 细胞 融合

[12:05.13]gene tale up residence identical

[12:11.85]基因 住进 居住 同一个

[12:18.56]genetically twin beforehand oppose

[12:24.31]遗传上 双胞胎之一 事先 反对

[12:30.05]theoretical pragmatism

[12:33.70]理论的 实用观点

[12:37.34]compromise morally plague humanity

[12:44.34]妥协 道德上 使痛苦 人类

[12:51.34]potential tolerate ancient vanity

[12:57.50]潜力 容忍 古代的 自负

[13:03.65]donor catalog terrify replica

[13:08.74]捐赠人 目录 使恐惧 复制品

[13:13.83]lottery normally unpredictable mixture

[13:18.33]抽签 正常地 不可预测的 混合物

[13:22.82]brilliant inherit purity innocence

[13:28.69]才华横溢的 继承 纯净 清白

[13:34.55]comment genius atomic let loose

[13:39.76]评论 天才 原子的 释放

[13:44.97]curiosity physicist atom multi-layered

[13:50.00]好奇心 物理学家 原子 多层次的

[13:55.03]reprogram transplant marrow leukemia

[14:01.98]重新编程 移植 骨髓 白血病

[14:08.93]lash out at immune merge technician

[14:14.10]严厉斥责 免疫的 使合并 技术员

[14:19.27]protein primitive embryo start out

[14:23.14]蛋白质 原始的 胚胎 起初意图

[14:27.00]grow into batch inconceivable kidney

[14:32.49]长成 一组 不可思议的 肾

[14:41.99]肝脏 无限的 假设的

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