长寿啮齿动物有完善的大脑保护机制

时间：2012-05-14 06:08:44

（单词翻译:单击）

The typical naked mole1 rat lives 25 to 30 years, during which it shows little decline in activity, bone health, reproductive capacity and cognitive2 ability. What is the secret to this East African rodent3's long, healthy life? Scientists from the United States and Israel found a clue. From infancy4 to old age, naked mole rats are blessed with large amounts of a protein essential for normal brain function.

"Naked mole rats have the highest level of a growth factor called NRG-1 in the cerebellum（小脑） . Its levels are sustained throughout their life, from development through adulthood," said Yael Edrey, doctoral student at The University of Texas Health Science Center San Antonio's Barshop Institute for Longevity5 and Aging Studies.

Comparison across 7 species

The Barshop Institute has the largest colony of naked mole rats in the U.S. -- 2,000 rodents6 scampering7 around a network of tubes and cages in humid conditions that mimic8 their natural underground habitat. Edrey is the lead author of research that compared lifelong NRG-1 levels across seven species of rodents, from mice and guinea pigs（豚鼠） to blind mole rats and Damaraland mole rats.

NRG-1 levels were monitored in naked mole rats at different ages ranging from 1 day to 26 years. The other six rodent species have maximum life spans of three to 19 years.

The cerebellum coordinates9 movements and maintains bodily equilibrium10（均衡，平静） . The research team hypothesized that long-lived species would maintain higher levels of NRG-1 in this region of the brain, with simultaneous healthy activity levels.

Among each of the species, the longest-lived members exhibited the highest lifelong levels of NRG-1. The naked mole rat had the most robust11 and enduring supply. "In both mice and in humans, NRG-1 levels go down with age," Edrey said.


分享到：


点击收听单词发音收听单词发音  

1 mole 26Nzn     
n.胎块；痣；克分子
参考例句：
  • She had a tiny mole on her cheek.她的面颊上有一颗小黑痣。
  • The young girl felt very self- conscious about the large mole on her chin.那位年轻姑娘对自己下巴上的一颗大痣感到很不自在。
2 cognitive Uqwz0     
adj.认知的，认识的，有感知的
参考例句：
  • As children grow older,their cognitive processes become sharper.孩子们越长越大，他们的认知过程变得更为敏锐。
  • The cognitive psychologist is like the tinker who wants to know how a clock works.认知心理学者倒很像一个需要通晓钟表如何运转的钟表修理匠。
3 rodent DsNyh     
n.啮齿动物；adj.啮齿目的
参考例句：
  • When there is a full moon,this nocturnal rodent is careful to stay in its burrow.月圆之夜，这种夜间活动的啮齿类动物会小心地呆在地洞里不出来。
  • This small rodent can scoop out a long,narrow tunnel in a very short time.这种小啮齿动物能在很短的时间里挖出一条又长又窄的地道来。
4 infancy F4Ey0     
n.婴儿期；幼年期；初期
参考例句：
  • He came to England in his infancy.他幼年时期来到英国。
  • Their research is only in its infancy.他们的研究处于初级阶段。
5 longevity C06xQ     
n.长命；长寿
参考例句：
  • Good habits promote longevity.良好的习惯能增长寿命。
  • Human longevity runs in families.人类的长寿具有家族遗传性。
6 rodents 1ff5f0f12f2930e77fb620b1471a2124     
n.啮齿目动物( rodent的名词复数 )
参考例句：
  • Rodents carry diseases and are generally regarded as pests. 啮齿目动物传播疾病，常被当作害虫对待。 来自《简明英汉词典》
  • Some wild rodents in Africa also harbor the virus. 在非洲，有些野生啮齿动物也是储毒者。 来自辞典例句
7 scampering 5c15380619b12657635e8413f54db650     
v.蹦蹦跳跳地跑，惊惶奔跑( scamper的现在分词 )
参考例句：
  • A cat miaowed, then was heard scampering away. 马上起了猫叫，接着又听见猫逃走的声音。 来自汉英文学 - 家（1-26） - 家（1-26）
  • A grey squirrel is scampering from limb to limb. 一只灰色的松鼠在树枝间跳来跳去。 来自辞典例句
8 mimic PD2xc     
v.模仿，戏弄；n.模仿他人言行的人
参考例句：
  • A parrot can mimic a person's voice.鹦鹉能学人的声音。
  • He used to mimic speech peculiarities of another.他过去总是模仿别人讲话的特点。
9 coordinates 8387d77faaaa65484f5631d9f9d20bfc     
n.相配之衣物；坐标( coordinate的名词复数 )；（颜色协调的）配套服装；[复数]女套服；同等重要的人（或物）v.使协调，使调和( coordinate的第三人称单数 )；协调；协同；成为同等
参考例句：
  • The town coordinates on this map are 695037. 该镇在这幅地图上的坐标是695037。 来自《简明英汉词典》
  • The UN Office for the Coordination of Humanitarian Affairs, headed by the Emergency Relief Coordinator, coordinates all UN emergency relief. 联合国人道主义事务协调厅在紧急救济协调员领导下，负责协调联合国的所有紧急救济工作。 来自《简明英汉词典》
10 equilibrium jiazs     
n.平衡，均衡，相称，均势，平静
参考例句：
  • Change in the world around us disturbs our inner equilibrium.我们周围世界的变化扰乱了我们内心的平静。
  • This is best expressed in the form of an equilibrium constant.这最好用平衡常数的形式来表示。
11 robust FXvx7     
adj.强壮的，强健的，粗野的，需要体力的，浓的
参考例句：
  • She is too tall and robust.她个子太高，身体太壮。
  • China wants to keep growth robust to reduce poverty and avoid job losses,AP commented.美联社评论道，中国希望保持经济强势增长，以减少贫困和失业状况。

©2005-2010英文阅读网