国产重口老太和小伙乱,国产精品久久久久影院嫩草,国产精品爽爽v在线观看无码 ,国产精品无码免费专区午夜,国产午夜福利100集发布

  時政|經(jīng)濟|社會|熱圖|專題|節(jié)會|人事變動|地方企業(yè)|文化 •  旅游|
  各地: 安徽 北京 重慶 大連 福建 廣東 廣西 海南 黑龍江 河南 湖北 湖南 吉林 江蘇 遼寧 四川 山東 上海 陜西 深圳 天津 新疆 云南 浙江
中國在線>學英語
日本培育出人工精子 沒男性也能生育后代
2011-08-08 16:17:39      來源:中國日報

打印文章 發(fā)送給好友 分享按鈕

日本培育出人工精子 沒男性也能生育后代

Sperm were artificially created in a breakthrough experiment which raises ethical questions. Here a sperm approaches an egg(dailymail.co.uk)

Scientists have used artificial sperm to restore fertility in a breakthrough that could allow thousands of men to fulfill their dream of fatherhood.

In ‘hugely exciting’ experiments, they have made sperm from scratch, and, for the first time, succeeded in using it to produce healthy young.

Remarkably, the baby mice in the experiments went on to have offspring themselves. The landmark research paves the way for new drugs for infertility, the heartbreaking but little-understood condition that affects one in six couples.

But it also opens a Pandora’s boxof ethical dilemmas. Possibilities raised range from men being made ‘redundant’ from the process of creating life, to babies being created through entirely artificial means.

Critics also question whether it is right to meddle withthe building blocksof life just to allow couples to satisfy their desire to have children.

Scientists have been trying for years to coaxembryonic stem cells – ‘master cells’ widely seen as a repair kit for the body – into turning into sperm. They have had some success but any mice that became pregnant by such means gave birth to unhealthy offspring that quickly died.

Now, Japanese scientists have come up with a series of steps that appear to solve the problem.

They started with stem cells taken from mouse embryos in the first days of life and, using a cocktail of chemicals and vitamins, turned them into sperm in the earliest stages of development. These were then transplanted into the testicles of infertile mice, where they grew into fully-functional sperm.

   上一頁 1 2 下一頁  


新聞熱搜
 
商訊
專題
聚焦南方洪澇災(zāi)害
>> 詳細

各地新聞
十一屆三中全會標志著中國共產(chǎn)黨重新確立了馬克思主義的思想路線、政治路線、組織路線,標志著中國共產(chǎn)黨人在新的時代條件下的偉大覺醒,顯示了中國共產(chǎn)黨順應(yīng)時代潮流和人民愿望、勇敢開辟建設(shè)社會主義新道路的決心。>> 詳細
點擊排行
  發(fā)展改革委:國內(nèi)成品油價暫不具備下調(diào)條件
國務(wù)院通知印發(fā)中國婦女發(fā)展綱要和兒童發(fā)展綱要
 
視覺