久久精品30_一本色道久久精品_激情综合视频_欧美日韩一区二区高清_好看的av在线不卡观看_国产自产精品_91久久黄色_午夜亚洲福利_欧美黄在线观看_国内自拍一区


www.jhzsvip.com
November 22, 2002



Scientists Announce Human Cloning Attempt

Scientists at an international conference in Washington announced on Tuesday that they will soon pioneer efforts to clone humans, unleashing a furor in the scientific community over the morality of creating duplicates of living people.

A team of researchers, led by Italian embryologist Severino Antinori, announced at the US National Academy of Sciences that they would carry out experiments in an effort to help childless couples become biological parents.

Antinori told US media in interviews earlier on Tuesday that he hoped to begin the experiments within weeks.

"We hope that in November we will begin to do the nuclear transfer, which in actuality is a transfer of the nucleus of ... a body cell into the egg of a woman for the purpose of establishing an embryo," he told CNN television.

"That embryo will be transferred into the uterus to establish a pregnancy."

According to media reports that experiments would be conducted on up to 200 women, impregnating them with cloned embryos.

Scientists long have warned, however, about a multitude of difficulties associated with cloning mammals, including miscarriage, premature delivery, genetic abnormalities and stillbirths.

The most outspoken critics have warned that in the process of creating a healthy human clone, scientists could create dozens of deformed human specimens.

To date, five types of mammals -- sheep, mice, goats, cows and pigs -- have been cloned, with dismal results, most dying at various stages of embryonic development or soon after birth.

"The basic biological problem is absolutely similar in all mammals, and humans are mammals," warned Rudolf Jaenisch, a cloning specialist at the Massachusetts Institute of Technology.

"We do not know the extent of the problem that we have" with genetic defects in clones he said. "I think that this is not good science."

But Panos Zavos, a colleague of Antinori's, told the conference that exhaustive measures would be taken to ensure human clones would not suffer the kinds of genetic damage common to other cloned mammals.

"We're not perfect, but we're trying to get there as perfectly as we can," Zavos said.

The researchers said a procedure called pre-implantation diagnosis would be used to test the viability of embryos and fetuses at various stages of development to screen for genetic abnormalities.

Zavos said cloning offers a humane option for couples unable to reproduce using the father's semen and mother's eggs.

"Infertility is a disease," the Greek-Cypriot scientist said. "Those couples need some sort of assistance to be able to bear children."

Most US infertility organizations, including the American Society for Reproductive Medicine, have come out strongly against human cloning.

"The many problems seen in cows and sheep that have been cloned, while unfortunate in animals, would be a disaster in human beings," said Michael Soules, president of the ASRM at a hearing on Capitol Hill several months ago.

Meanwhile, a vacationing US President George W. Bush, who is struggling with an imminent decision on whether to allow federal funding for controversial stem cell research -- including on embryonic cells -- weighed in on the debate.

"I'll be making my comments about my view about how life and science should interface when I'm ready," he said from his ranch in Crawford, Texas.

A decision on the issue, considered to be one of the toughest Bush has faced since he taking the presidency, is expected by September.

(Chinadaily.com.cn 08/08/2001)

In This Series
References

Archive

Web Link


Copyright © 2001 China Internet Information Center. All Rights Reserved
E-mail: webmaster@china.org.cn Tel: 86-10-68326688

久久精品30_一本色道久久精品_激情综合视频_欧美日韩一区二区高清_好看的av在线不卡观看_国产自产精品_91久久黄色_午夜亚洲福利_欧美黄在线观看_国内自拍一区
99精品视频中文字幕| 亚洲国产一区二区精品专区| 日本亚洲三级在线| 亚洲综合网站在线观看| 日韩毛片高清在线播放| 亚洲欧美综合网| 日韩美女视频一区二区| 日韩理论电影院| 亚洲日本va午夜在线影院| 亚洲色欲色欲www| 亚洲激情图片qvod| 亚洲国产中文字幕| 日本在线观看不卡视频| 欧美aⅴ一区二区三区视频| 日韩国产在线观看一区| 国内精品久久久久影院薰衣草| 精品在线观看免费| 成人一区二区三区中文字幕| av在线免费不卡| 亚洲视频一区| 国产一区二区高清视频| 欧美性大战久久久| 欧美日韩高清在线| 精品国免费一区二区三区| 国产日产欧产精品推荐色| 亚洲欧美另类图片小说| 丝袜美腿高跟呻吟高潮一区| 国产一区二区三区黄视频| 不卡一卡二卡三乱码免费网站| 欧美一区1区三区3区公司| 亚洲激情社区| 欧美视频自拍偷拍| 国产情人综合久久777777| 中文字幕制服丝袜一区二区三区| 亚洲黄色免费电影| 精品无码三级在线观看视频| 91日韩在线专区| 午夜亚洲性色福利视频| 欧美一区二区福利视频| 国产精品福利在线播放| 美女免费视频一区二区| 91在线精品一区二区三区| aa亚洲婷婷| 日韩一区二区三区视频| 亚洲视频精选在线| 国产精一品亚洲二区在线视频| 欧美一区2区三区4区公司二百 | 日韩亚洲一区在线播放| 欧美亚洲综合一区| 日本一区二区三区四区在线视频| 亚洲成人av一区二区三区| 国产激情一区二区三区桃花岛亚洲| 午夜久久久久| 欧美三区免费完整视频在线观看| 国产亚洲美州欧州综合国| 亚洲国产精品久久久男人的天堂 | 99精品热6080yy久久| 69堂国产成人免费视频| 一级女性全黄久久生活片免费| 国产精品一区一区| 午夜在线a亚洲v天堂网2018| 精品国产乱码久久久久久蜜臀| 亚洲国产视频网站| 91麻豆自制传媒国产之光| 欧美性色黄大片| 亚洲欧洲日韩综合一区二区| 国产精品一级片在线观看| 国产精品视频| 欧美激情综合在线| 国产成人精品亚洲日本在线桃色 | 日韩欧美一级精品久久| 偷窥国产亚洲免费视频| 亚洲欧洲精品一区| xnxx国产精品| 国产黄色精品网站| 91福利资源站| 亚洲国产精品久久人人爱蜜臀| 色综合天天综合网天天狠天天| 欧美二区三区91| 免费在线成人网| 销魂美女一区二区三区视频在线| 久久久久久久久久久久电影| 国产综合久久久久影院| 久久久久久一区二区| 亚洲夂夂婷婷色拍ww47| 欧美午夜视频| 中文字幕av不卡| 91色.com| 国产农村妇女精品| 91在线国产观看| 久久精品在线免费观看| a级精品国产片在线观看| 91精品国产综合久久久久| 久久99精品久久久| 欧洲一区在线观看| 欧美aaaaa成人免费观看视频| 久久久久久亚洲精品不卡4k岛国| 一级精品视频在线观看宜春院 | 国产精品日产欧美久久久久| 91麻豆精品在线观看| 2022国产精品视频| 成人激情视频网站| 精品国产99国产精品| 99视频在线精品| 久久久蜜臀国产一区二区| 91亚洲精华国产精华精华液| 精品福利在线导航| 91麻豆国产自产在线观看| 国产农村妇女毛片精品久久麻豆 | 欧美在线免费观看视频| 日韩福利视频导航| 欧美日韩一区二区欧美激情| 黄色小说综合网站| 91精品国产91久久久久久一区二区 | 午夜天堂精品久久久久| 中国色在线观看另类| 亚洲日韩视频| 亚洲123区在线观看| 日本乱码高清不卡字幕| 国产一区高清在线| 久久影院午夜片一区| 欧美日韩国产高清视频| 依依成人精品视频| 久久只有精品| 国产99久久久精品| 久久精品视频一区| 一本色道久久综合亚洲精品不卡| 亚洲一区二区精品久久av| 91黄色激情网站| 成人精品视频.| 国产精品久久久久久久第一福利| 99国产精品私拍| 蜜臀99久久精品久久久久久软件| 4438x成人网最大色成网站| 欧美一区二区三区免费看| 一区二区三区四区不卡在线| 欧美偷拍一区二区| 女女同性精品视频| 亚洲国产三级在线| 91精品国产欧美日韩| 伊人久久大香线蕉av超碰演员| 日韩精品国产欧美| 欧美va亚洲va香蕉在线| 亚洲国产欧洲综合997久久| 美女网站一区二区| 国产欧美一区二区三区网站| 久久久久高清| av不卡在线播放| 亚洲bt欧美bt精品| 精品人在线二区三区| 亚洲一卡久久| 成人h版在线观看| 午夜av电影一区| 久久精品一级爱片| 欧美性生活久久| 狠狠综合久久av一区二区老牛| 免费久久99精品国产| 成人高清免费观看| 日韩精品一区第一页| 亚洲国产精品99久久久久久久久| 欧美伊人久久久久久午夜久久久久| 欧美激情麻豆| 国产毛片精品一区| 亚洲成a人片综合在线| 久久精品视频一区二区| 欧美图区在线视频| 国产视频精品网| 欧美人与禽猛交乱配视频| 久久成人免费网| 亚洲中国最大av网站| 中文字幕第一区二区| 欧美精品123区| 免费在线欧美黄色| 精品二区视频| 国产69精品久久777的优势| 日韩av一区二区三区| 亚洲美腿欧美偷拍| 国产欧美中文在线| 精品日韩99亚洲| 在线观看91av| 91国产丝袜在线播放| 一区二区三区福利| 欧美日韩在线一二三| 成人精品国产福利| 久久精品国产一区二区| 亚洲123区在线观看| 亚洲日本一区二区| 国产精品久久久久久久久果冻传媒 | 国产欧美视频在线观看| 日韩一区二区视频| 欧美精品在线一区二区| 免费一区二区三区| 亚洲国产欧美日韩| 国产一区清纯| 欧美在线高清| 色综合天天综合给合国产| 成人的网站免费观看| 成人性色生活片免费看爆迷你毛片| 免费在线欧美视频| 另类调教123区|