大學(xué)英語綜合教程第三冊(cè) 15

[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 開始禿頂?shù)?胚胎學(xué)家 [11:28.54]pregnancy give birth to champagne veterinarian [11:34.82]懷孕 產(chǎn)生 香檳酒 獸醫(yī) [11:41.10]for all the world dot creation union [11:46.65]在各個(gè)方面 散步于 創(chuàng)造物 結(jié)合 [11:52.20]sperm udder cell fuse [11:58.67]精子 乳房 細(xì)胞 融合 [12:05.13]gene tale up residence identical [12:11.85]基因 住進(jìn) 居住 同一個(gè) [12:18.56]genetically twin beforehand oppose [12:24.31]遺傳上 雙胞胎之一 事先 反對(duì) [12:30.05]theoretical pragmatism [12:33.70]理論的 實(shí)用觀點(diǎn) [12:37.34]compromise morally plague humanity [12:44.34]妥協(xié) 道德上 使痛苦 人類 [12:51.34]potential tolerate ancient vanity [12:57.50]潛力 容忍 古代的 自負(fù) [13:03.65]donor catalog terrify replica [13:08.74]捐贈(zèng)人 目錄 使恐懼 復(fù)制品 [13:13.83]lottery normally unpredictable mixture [13:18.33]抽簽 正常地 不可預(yù)測(cè)的 混合物 [13:22.82]brilliant inherit purity innocence [13:28.69]才華橫溢的 繼承 純凈 清白 [13:34.55]comment genius atomic let loose [13:39.76]評(píng)論 天才 原子的 釋放 [13:44.97]curiosity physicist atom multi-layered [13:50.00]好奇心 物理學(xué)家 原子 多層次的 [13:55.03]reprogram transplant marrow leukemia [14:01.98]重新編程 移植 骨髓 白血病 [14:08.93]lash out at immune merge technician [14:14.10]嚴(yán)厲斥責(zé) 免疫的 使合并 技術(shù)員 [14:19.27]protein primitive embryo start out [14:23.14]蛋白質(zhì) 原始的 胚胎 起初意圖 [14:27.00]grow into batch inconceivable kidney [14:32.49]長(zhǎng)成 一組 不可思議的 腎 [14:41.99]肝臟 無限的 假設(shè)的

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