英语新闻听写 研究表明维生素A缺乏对干细胞有害

According to a new study from the German Cancer Research Center, deficiencies in vitamin A can be detrimental¹ to blood stem cells.

根据德国癌症研究中心的一项新研究，维生素A不足可能对血液干细胞有害。

These specialized² cells in the skin, gut³, or blood have a relatively⁴ short lifespan and require constant replenishment⁵.

皮肤、肠道或血液中的这些特殊细胞的寿命相对较短，需要不断补充。

In 2008, researchers discovered a group of special stem cells in the bone marrow⁶ that remain dormant⁷ most of the time

2008年，研究人员在骨髓中发现了一组特殊的干细胞，这些细胞大部分时间都处于休眠状态，

and only become active to fight bacterial⁸ or viral infections, heavy blood loss or as a reaction to chemotherapy.

只有在对抗细菌或病毒感染，严重失血或化疗反应时变得活跃。

Researchers have now identified the mechanisms⁹ that activate¹⁰ and deactivate¹¹ the stem cells.

研究人员已经确定了激活和停用干细胞的机制。

Results showed that retinoic acid, a vitamin A metabolite crucial to the process.

结果表明维生素A代谢物视黄酸是过程的关键。

Researchers hope the findings will play a role in cancer treatments because cancer cells, like stem cells, rest in a state of dormancy¹² and their metabolism¹³ is completely shut down, rendering¹⁴ them resistant¹⁵ to chemotherapy.

研究人员希望这项发现有助于癌症治疗，因为癌细胞如干细胞处于休眠状态，代谢作用完全关闭，致使其抗化疗。

1 detrimental   

adj.损害的，造成伤害的

参考例句：

• We know that heat treatment is detrimental to milk.我们知道加热对牛奶是不利的。
• He wouldn't accept that smoking was detrimental to health.他不相信吸烟有害健康。

2 specialized   

adj.专门的，专业化的

参考例句：

• There are many specialized agencies in the United Nations.联合国有许多专门机构。
• These tools are very specialized.这些是专用工具。

3 gut   

n.[pl.]胆量；内脏；adj.本能的；vt.取出内脏

参考例句：

• It is not always necessary to gut the fish prior to freezing.冷冻鱼之前并不总是需要先把内脏掏空。
• My immediate gut feeling was to refuse.我本能的直接反应是拒绝。

4 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

5 replenishment   

n.补充(货物)

参考例句：

• Since the wartime population needed replenishment, pregnancies were a good sign. 最后一桩倒不失为好现象，战时人口正该补充。
• Natural replenishment of this vast supply of underground water occurs very slowly. 靠自然补充大量地下水是十分缓慢的。

6 marrow   

n.骨髓；精华；活力

参考例句：

• It was so cold that he felt frozen to the marrow. 天气太冷了，他感到寒冷刺骨。
• He was tired to the marrow of his bones.他真是累得筋疲力尽了。

7 dormant   

adj.暂停活动的；休眠的；潜伏的

参考例句：

• Many animals are in a dormant state during winter.在冬天许多动物都处于睡眠状态。
• This dormant volcano suddenly fired up.这座休眠火山突然爆发了。

8 bacterial   

a.细菌的

参考例句：

• Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
• Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

9 mechanisms   

n.机械( mechanism的名词复数 )；机械装置；[生物学] 机制；机械作用

参考例句：

• The research will provide direct insight into molecular mechanisms. 这项研究将使人能够直接地了解分子的机理。 来自《简明英汉词典》
• He explained how the two mechanisms worked. 他解释这两台机械装置是如何工作的。 来自《简明英汉词典》

10 activate   

vt.使活动起来，使开始起作用

参考例句：

• We must activate the youth to study.我们要激励青年去学习。
• These push buttons can activate the elevator.这些按钮能启动电梯。

11 deactivate   

v.使无效；复员

参考例句：

• Russia is deactivating some of its deadliest missiles.俄罗斯正在拆除其一些最危险的导弹。
• I go through several complex steps to try to "deactivate" my profile.我尝试了那些复杂的步骤，试图“撤销”我的个人资料。

12 dormancy   

n.睡眠，冬眠，隐匿

参考例句：

• During dormancy the plants must be kept very dry. 在休眠期，植物必须保持非常干燥。 来自辞典例句
• It may also come to the point of virtual dormancy. 它也可以达到实际上的潜伏状态。 来自辞典例句

13 metabolism   

n.新陈代谢

参考例句：

• After years of dieting,Carol's metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。
• All living matter undergoes a process of metabolism.生物都有新陈代谢。

14 rendering   

n.表现，描写

参考例句：

• She gave a splendid rendering of Beethoven's piano sonata.她精彩地演奏了贝多芬的钢琴奏鸣曲。
• His narrative is a super rendering of dialect speech and idiom.他的叙述是方言和土语最成功的运用。

15 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。