VOA慢速英语:A Way to Make New Eggs in Women?

New research could raise hope for women who are having trouble getting pregnant.
新研究可能为怀孕有问题的妇女带来希望。

For years, the thinking has been that women are born with all the eggs their bodies will ever produce. In fact, this has been the thinking not just about humans but all mammals.
多年来，人们一直以来的观点是，妇女身体产生的卵细胞在出生时就已经决定了。事实上，这不仅仅只是关于人类，而是所有的哺乳动物。
 

Then, in two thousand four, a researcher at Massachusetts General Hospital reported a surprising discovery. Jonathan Tilly found that adult female mice could produce new eggs.
然后，在2004年，马萨诸塞州总医院的研究人员Jonathan Tilly报告了一个惊人的发现。Jonathan Tilly发现，成年雌鼠能产生新的卵子。

Now, Jonathan Tilly has extended his work and reported another discovery -- this time about human females.
现在，Jonathan Tilly已经拓展了他的研究并报告了另一项发现，这次是关于女性的。

JONATHAN TILLY: "We've isolated, essentially, the female equivalent of the stem cells that we know exist in men that actively make new sperm. So having these cells now isolated, I think, opens up a lot of opportunities to consider that we simply couldn't fathom before."
JONATHAN TILLY：“基本上，我们已经分离出了女性身体中相当于男性身体产生新精子的干细胞。所以，有了这些分离出来的细胞，我认为开启了许多机会去研究我们以前根本无法理解的东西。”
 

Stem cells are special kinds of cells. Starting in embryos just a few days old, they produce the many different cell types and tissues that form the body. In some adult tissues, stem cells produce replacements for damaged or worn out cells.
干细胞是特殊类型的细胞，从只有数天的胚胎开始，它们生成了许多不同类型的细胞和身体组织。在一些长成的组织中，干细胞为损坏或老旧细胞生成替代品。

In his new study, Jonathan Tilly and other researchers removed cells from ovaries. Ovaries are the female reproductive organs that produce eggs. The scientists did laboratory tests to make sure they had the right cells that they were looking for. Then they used what are known as culturing methods to grow the cells so they would divide and produce more cells.
在他的新研究中，Jonathan Tilly和其他研究人员取出了卵巢细胞。卵巢是产生卵子的女性生殖器官。科学家做了化验，以确保他们能够找到的合适的细胞。然后，他们使用所谓的培养方法培养细胞，这样它们就能分裂和产生更多细胞。

JONATHAN TILLY: "And we could start with perhaps one hundred cells, and over several months' time take those one hundred cells and make hundreds of thousands of cells. And interestingly, we noticed that these cells would spontaneously generate immature eggs, all on their own, in these cultures."
JONATHAN TILLY：“而我们可以从100个细胞开始，在几个月的时间内让它们产生成千上万的细胞。有意思的是,我们注意到这些细胞会自发地产生未成熟的卵子，在这类培养中完全依靠自身。”

The researchers did not stop there. They wanted to further confirm the ability of these cells to make eggs. They placed some of the cells into human ovary tissue. Then they implanted the tissue under the skin of laboratory mice.
研究人员并没有就此停止。他们希望进一步确认这些细胞产生卵子的能力。他们将其中一些细胞放置在人类卵巢组织里。然后，他们将该组织植入实验鼠皮肤下。

The studies found that these human cells were -- in Jonathan Tilly's words -- "more than happy to create brand-new human egg cells." He says growing eggs in the lab could improve the chances for women who are having the process known as in vitro fertilization. With IVF, an egg is fertilized with sperm in a laboratory, then placed in the woman's uterus to develop.
研究发现，这些人体细胞--用Jonathan Tilly的话来说就是--“更乐意创造全新的人类卵细胞。” 他说，在实验室中培育卵子可以提高正在进行体外受精的女性怀孕的机会。通过体外受精，卵子在实验室中受精，然后放入女性的子宫中成长。
 
Jonathan Tilly says his work could also lead to fertility treatments that might improve the chances for more traditional fertilization methods.
Jonathan Tilly说，他的工作可能也导致一种提高多数传统受精方式几率的生育治疗。

JONATHAN TILLY: "We can also think about, perhaps, targeting these cells in the ovaries with hormones that these cells like, and thereby increasing their activity and perhaps increasing the size of the egg cell reserve in the ovary, when it would be desirable to do so."
JONATHAN TILLY：“我们也可以想想，或许，针对这些卵巢中的细胞使用它们喜欢的激素，从而增加他们的活动，又或者当它需要时，增加卵巢中卵细胞的储存规模。”

His paper on making new human eggs from stem cells was published online this week by the journal Nature Medicine. Some experts raised questions about his earlier work with mice. Some are not so sure about this study either, until other researchers can reproduce the findings.
他这篇关于从干细胞中制造新人类卵子的论文本周被《自然医学》杂志发布在网上。一些专家就他对老鼠的早期研究提出了疑问。但有些研究人员对这项研究也还不敢确认，除非有其他研究人员能再现该结果。