没男性也能生育后代 日本培育出人工精子
<p><span word="Scientists">Scientists</span> <span word="have">have</span> <span word="used">used</span> <span word="artificial">artificial</span> <span word="sperm">sperm</span> <span word="to">to</span> <span word="restore">restore</span> <span word="fertility">fertility</span> <span word="in">in</span> <span word="a">a</span> <span word="breakthrough">breakthrough</span> <span word="that">that</span> <span word="could">could</span> <span word="allow">allow</span> <span word="thousands">thousands</span> <span word="of">of</span> <span word="men">men</span> <span word="to">to</span> <span word="fulfill">fulfill</span> <span word="their">their</span> <span word="dream">dream</span> <span word="of">of</span> <span word="fatherhood">fatherhood</span>.</p><p><span word="In">In</span> ‘<span word="hugely">hugely</span> <span word="exciting">exciting</span>’ <span word="experiments">experiments</span>, <span word="they">they</span> <span word="have">have</span> <span word="made">made</span> <span word="sperm">sperm</span> <span word="from">from</span> <span word="scratch">scratch</span>, <span word="and">and</span>, <span word="for">for</span> <span word="the">the</span> <span word="first">first</span> <span word="time">time</span>, <span word="succeeded">succeeded</span> <span word="in">in</span> <span word="using">using</span> <span word="it">it</span> <span word="to">to</span> <span word="produce">produce</span> <span word="healthy">healthy</span> <span word="young">young</span>.</p><p><span word="Remarkably">Remarkably</span>, <span word="the">the</span> <span word="baby">baby</span> <span word="mice">mice</span> <span word="in">in</span> <span word="the">the</span> <span word="experiments">experiments</span> <span word="went">went</span> <span word="on">on</span> <span word="to">to</span> <span word="have">have</span> <span word="offspring">offspring</span> <span word="themselves">themselves</span>. <span word="The">The</span> <span word="landmark">landmark</span> <span word="research">research</span> <span word="paves">paves</span> <span word="the">the</span> <span word="way">way</span> <span word="for">for</span> <span word="new">new</span> <span word="drugs">drugs</span> <span word="for">for</span> <span word="infertility">infertility</span>, <span word="the">the</span> <span word="heartbreaking">heartbreaking</span> <span word="but">but</span> <span word="little">little</span>-<span word="understood">understood</span> <span word="condition">condition</span> <span word="that">that</span> <span word="affects">affects</span> <span word="one">one</span> <span word="in">in</span> <span word="six">six</span> <span word="couples">couples</span>.</p><p><span word="But">But</span> <span word="it">it</span> <span word="also">also</span> <span word="opens">opens</span> <span word="a">a</span> <span word="Pandora">Pandora</span>’<span word="s">s</span> <span word="box">box</span> <span word="of">of</span> <span word="ethical">ethical</span> <span word="dilemmas">dilemmas</span>. <span word="Possibilities">Possibilities</span> <span word="raised">raised</span> <span word="range">range</span> <span word="from">from</span> <span word="men">men</span> <span word="being">being</span> <span word="made">made</span> ‘<span word="redundant">redundant</span>’ <span word="from">from</span> <span word="the">the</span> <span word="process">process</span> <span word="of">of</span> <span word="creating">creating</span> <span word="life">life</span>, <span word="to">to</span> <span word="babies">babies</span> <span word="being">being</span> <span word="created">created</span> <span word="through">through</span> <span word="entirely">entirely</span> <span word="artificial">artificial</span> <span word="means">means</span>.</p><p><span word="Critics">Critics</span> <span word="also">also</span> <span word="question">question</span> <span word="whether">whether</span> <span word="it">it</span> <span word="is">is</span> <span word="right">right</span> <span word="to">to</span> <span word="meddle">meddle</span> <span word="with">with</span> <span word="the">the</span> <span word="building">building</span> <span word="blocks">blocks</span> <span word="of">of</span> <span word="life">life</span> <span word="just">just</span> <span word="to">to</span> <span word="allow">allow</span> <span word="couples">couples</span> <span word="to">to</span> <span word="satisfy">satisfy</span> <span word="their">their</span> <span word="desire">desire</span> <span word="to">to</span> <span word="have">have</span> <span word="children">children</span>.</p><p><span word="Scientists">Scientists</span> <span word="have">have</span> <span word="been">been</span> <span word="trying">trying</span> <span word="for">for</span> <span word="years">years</span> <span word="to">to</span> <span word="coax">coax</span> <span word="embryonic">embryonic</span> <span word="stem">stem</span> <span word="cells">cells</span> – ‘<span word="master">master</span> <span word="cells">cells</span>’ <span word="widely">widely</span> <span word="seen">seen</span> <span word="as">as</span> <span word="a">a</span> <span word="repair">repair</span> <span word="kit">kit</span> <span word="for">for</span> <span word="the">the</span> <span word="body">body</span> – <span word="into">into</span> <span word="turning">turning</span> <span word="into">into</span> <span word="sperm">sperm</span>. <span word="They">They</span> <span word="have">have</span> <span word="had">had</span> <span word="some">some</span> <span word="success">success</span> <span word="but">but</span> <span word="any">any</span> <span word="mice">mice</span> <span word="that">that</span> <span word="became">became</span> <span word="pregnant">pregnant</span> <span word="by">by</span> <span word="such">such</span> <span word="means">means</span> <span word="gave">gave</span> <span word="birth">birth</span> <span word="to">to</span> <span word="unhealthy">unhealthy</span> <span word="offspring">offspring</span> <span word="that">that</span> <span word="quickly">quickly</span> <span word="died">died</span>.</p><p><span word="Now">Now</span>, <span word="Japanese">Japanese</span> <span word="scientists">scientists</span> <span word="have">have</span> <span word="come">come</span> <span word="up">up</span> <span word="with">with</span> <span word="a">a</span> <span word="series">series</span> <span word="of">of</span> <span word="steps">steps</span> <span word="that">that</span> <span word="appear">appear</span> <span word="to">to</span> <span word="solve">solve</span> <span word="the">the</span> <span word="problem">problem</span>.</p><p><span word="They">They</span> <span word="started">started</span> <span word="with">with</span> <span word="stem">stem</span> <span word="cells">cells</span> <span word="taken">taken</span> <span word="from">from</span> <span word="mouse">mouse</span> <span word="embryos">embryos</span> <span word="in">in</span> <span word="the">the</span> <span word="first">first</span> <span word="days">days</span> <span word="of">of</span> <span word="life">life</span> <span word="and">and</span>, <span word="using">using</span> <span word="a">a</span> <span word="cocktail">cocktail</span> <span word="of">of</span> <span word="chemicals">chemicals</span> <span word="and">and</span> <span word="vitamins">vitamins</span>, <span word="turned">turned</span> <span word="them">them</span> <span word="into">into</span> <span word="sperm">sperm</span> <span word="in">in</span> <span word="the">the</span> <span word="earliest">earliest</span> <span word="stages">stages</span> <span word="of">of</span> <span word="development">development</span>. <span word="These">These</span> <span word="were">were</span> <span word="then">then</span> <span word="transplanted">transplanted</span> <span word="into">into</span> <span word="the">the</span> <span word="testicles">testicles</span> <span word="of">of</span> <span word="infertile">infertile</span> <span word="mice">mice</span>, <span word="where">where</span> <span word="they">they</span> <span word="grew">grew</span> <span word="into">into</span> <span word="fully">fully</span>-<span word="functional">functional</span> <span word="sperm">sperm</span>.</p>
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