英语PK台 第454期:别熬夜了,缺觉危害大!

 　　We're only beginning to understand why we sleep to begin with, but we do know it's essential. Adults need 7 to 8 hours sleep at night, and adolescents need about 10. We grow sleepy due the signals from our body telling our brain we are tired, and signals from the environment telling us it's dark outside. The rise in sleep inducing chemicals, like adenosine and melatonin, send us into a light dose that grows deeper, making our breathing and heart rate slow down and our muscles relax. This non REM sleep is when DNA¹ is repaired and our bodies replenish² themselves for the day ahead.

　　我们也只刚刚才开始了解人类需要睡眠来开始美好的一天，但我们确实知其重要性。成年人每晚需要7至8小时的睡眠，青少年则需要10小时。我们觉得困倦是因为身体向大脑发出了疲倦的信号，也因为外界环境给予了我们天黑的信号。人体则加量分泌能增进睡意的化学物质，如腺苷和褪黑激素，让我们呼吸和心跳频率降低，并使肌肉放松。这种非快速眼动睡眠发生在DNA修复以及身体自我补给时。

　　In the United States, it's estimated that 30% of adults and 66% of adolescents are regularly sleep-deprived. This isn't just a minor³ inconvenience. Staying awake can cause serious bodily harm. When we lose sleep, learning, memory, mood, and reaction time are affected⁴. Sleeplessness⁵ may also cause inflammation, hallucinations, high blood pressure, and it's even been linked to diabetes⁶ and obesity⁷.

　　调查发现，美国30%的成年人与66%的青少年睡眠不足。可别小看了睡眠不足的后果。一直不睡觉会严重损害身体健康。当我们长时间不睡觉时，学习能力，记忆力，情绪以及反应能力将受到影响。缺乏睡眠也可能导致炎症，幻觉，高血压，甚至糖尿病和肥胖都与睡眠不足有关。

　　In 2014, a devoted⁸ soccer fan died after staying awake for 48hrs to watch the world cup. While his untimely death was due to a stroke, studies show that chronically⁹ sleeping fewer than 6 hours a night increasing stroke risk by 4.5 times, compared to those getting consistent 7 to 8 hours of shut-eye.

　　2014年就有一位足球死忠粉在持续48小时观看世界杯后死亡。虽说他的早逝归根结底是因为中风，但研究表明，夜间睡眠少期少于6小时的人同长期保持7-8小时睡眠的人相比中风的风险会增加4.5倍。

　　How can sleep deprivation¹⁰ cause such immense suffering? Scientists think the answer lies with the accumulation of waste products in the brain. During our waking hours, our cells are busy using up our day's energy sources, which get broken down into various by-products, including adenosine. As adenosine builds up, it increases the urge to sleep, also known as sleep pressure. In fact, caffeine works by blocking adenosine receptor pathways. Other waste products also build up in the brain, and if they're not cleared away, they collectively overload¹¹ the brain and our thought to lead to the many negative symptoms of sleep deprivation.

　　睡眠不足为何如此痛苦呢？科学家们认为其原由为大脑中废物的累积。当我们清醒时，细胞正忙于消耗我们一天中产生的能量，而这些能量的产生会分解出各种副产品，例如腺苷，腺苷的不断产生会使睡眠欲望增加，这样的欲望而被称作睡眠压力。事实上，咖啡因就是通过阻碍腺苷的接收途径来发挥作用的。其他的垃圾产物也会在大脑中堆积，如果他们不被清理掉，大脑将超负荷运转，同时可能会引起许多睡眠不足的不良症状。

　　So what's happening in our brain when we sleep, to prevent this? Scientists found something called the Glymphatic System, a clean-up mechanism¹² that removes this build up and is much more active when we're asleep. It works by using cerebrospinal fluid to flush away toxic¹³ by-products that accumulate between cells. Lymphatic vessels¹⁴, with serve as pathways for immune cells have recently been discovered in the brain, and they may also play a role in clearing out the brain's daily waste products.

　　所以当我们睡着时，大脑是如何防止这种情况发生的呢？科学家们发现了脑部的类淋巴系统，它是一种可以清除这些垃圾产物的清洁机制，并且在我们睡眠时比较活跃。这种机制利用脑脊髓液将细胞间积累的有毒副产品冲刷掉。最近，研究员发现，在大脑中作为免疫细胞通道的淋巴血管，这些血管可能也起到了清理大脑日常垃圾的作用。

　　While scientists continue exploring the restorative mechanisms¹⁵ behind sleep, we can be sure that sleeping into slumber¹⁶ is a necessity, if we wanna maintain our health and our sanity¹⁷.

　　尽管科学家们还在继续探索人睡着后的修复机制，我们可以肯定的是，如果我们想保持健康的身心，良好的睡眠是非常必要的。

1 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

2 replenish   

vt.补充；(把…)装满；(再)填满

参考例句：

• I always replenish my food supply before it is depleted.我总是在我的食物吃完之前加以补充。
• We have to import an extra 4 million tons of wheat to replenish our reserves.我们不得不额外进口四百万吨小麦以补充我们的储备。

3 minor   

adj.较小(少)的，较次要的；n.辅修学科；vi.辅修

参考例句：

• The young actor was given a minor part in the new play.年轻的男演员在这出新戏里被分派担任一个小角色。
• I gave him a minor share of my wealth.我把小部分财产给了他。

4 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

5 sleeplessness   

n.失眠，警觉

参考例句：

• Modern pharmacy has solved the problem of sleeplessness. 现代制药学已经解决了失眠问题。 来自《简明英汉词典》
• The doctors were puzzled by this strange continuous sleeplessness. 医生们对他的奇异的不眠感到疑惑。 来自英语晨读30分（高三）

6 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

7 obesity   

n.肥胖，肥大

参考例句：

• One effect of overeating may be obesity.吃得过多能导致肥胖。
• Sugar and fat can more easily lead to obesity than some other foods.糖和脂肪比其他食物更容易导致肥胖。

8 devoted   

adj.忠诚的，忠实的，热心的，献身于...的

参考例句：

• He devoted his life to the educational cause of the motherland.他为祖国的教育事业贡献了一生。
• We devoted a lengthy and full discussion to this topic.我们对这个题目进行了长时间的充分讨论。

9 chronically   

ad.长期地

参考例句：

• Similarly, any pigment nevus that is chronically irritated should be excised. 同样，凡是经常受慢性刺激的各种色素痣切勿予以切除。
• People chronically exposed to chlorine develop some degree of tolerance. 人长期接触氯气可以产生某种程度的耐受性。

10 deprivation   

n.匮乏；丧失；夺去，贫困

参考例句：

• Many studies make it clear that sleep deprivation is dangerous.多实验都证实了睡眠被剥夺是危险的。
• Missing the holiday was a great deprivation.错过假日是极大的损失。

11 overload   

vt.使超载；n.超载

参考例句：

• Don't overload the boat or it will sink.别超载，否则船会沉。
• Large meals overload the digestive system.吃得太饱会加重消化系统的负担。

12 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

13 toxic   

adj.有毒的，因中毒引起的

参考例句：

• The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
• There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。

14 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

15 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》

16 slumber   

n.睡眠，沉睡状态

参考例句：

• All the people in the hotels were wrapped in deep slumber.住在各旅馆里的人都已进入梦乡。
• Don't wake him from his slumber because he needs the rest.不要把他从睡眠中唤醒，因为他需要休息。

17 sanity   

n.心智健全，神智正常，判断正确

参考例句：

• I doubt the sanity of such a plan.我怀疑这个计划是否明智。
• She managed to keep her sanity throughout the ordeal.在那场磨难中她始终保持神志正常。