听力文摘：氧气有毒吗?

After all,too much oxygen can be toxic¹.

毕竟过多的氧气是有毒的。

After several days of breathing nothing but pure oxygen, you'd begin to experience nausea², dizziness, muscle twitches³, and convulsions.

只呼吸纯氧几天之后，你会觉得恶心，头昏眼花，肌肉痉挛，抽搐。

You might even die.

甚至你可能会死亡。

Ironically, too much oxygen actually inhibits⁴ ventilation and ends up slowing down the delivery of oxygen to your body's tissues.

讽刺的是，过多的氧气实际上会阻止空气流通，最终会减慢氧气在身体组织中的输送速度。

Another problem is that certain tissues, like the lining⁵ of the lungs and the walls of the arteries⁶, are very sensitive to oxygen.

另一个问题是，特定的组织，例如肺粘膜，动脉壁都对氧气很敏感。

The cornea is also very sensitive to oxygen; you may have heard of people who have gone blind because, as newborns, the oxygen levels in their incubators were too high.

眼角膜也对氧气很敏感，你或许听说过有人在婴儿时期因为恒温箱中的氧气量过高而失明的事情。

Scientists aren't really sure why oxygen affects the body this way.

科学家们不是很确定为什么氧气会这样影响身体。

Some think it has to do with a special form of the oxygen molecule⁷ which bonds with the proteins and membranes⁸ in the lining of the lungs, and ends up destroying them.

一些认为氧气分子以特殊的形式与肺粘膜上的蛋白质和细胞膜结合，最终破坏它们。

In other words, with too much oxygen around, your insides begin to oxidize.

换句话说，周围的氧气过多，身体内部会开始氧化。

1 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。

2 nausea   

n.作呕，恶心；极端的憎恶(或厌恶)

参考例句：

• Early pregnancy is often accompanied by nausea.怀孕期常有恶心的现象。
• He experienced nausea after eating octopus.吃了章鱼后他感到恶心。

3 twitches   

n.（使）抽动， （使）颤动， （使）抽搐( twitch的名词复数 )

参考例句：

• No response, just a flutter of flanks and a few ear twitches. 没反应，只有胁腹和耳朵动了几下。 来自互联网
• BCEF(50,100 mg·kg~-1 ) could distinctly increase the head-twitch number in the 5-HTP induced head-twitches test. BCEF50、100mg·kg-1可明显增加5羟色胺酸诱导甩头小鼠的甩头次数。 来自互联网

4 inhibits   

阻止，抑制( inhibit的第三人称单数 )； 使拘束，使尴尬

参考例句：

• A small manufacturing sector inhibits growth in the economy. 制造业规模太小有碍经济增长。
• His bad English inhibits him from speaking freely. 他英语学得不好，这使他不能表达自如。

5 lining   

n.衬里，衬料

参考例句：

• The lining of my coat is torn.我的外套衬里破了。
• Moss makes an attractive lining to wire baskets.用苔藓垫在铁丝篮里很漂亮。

6 arteries   

n.动脉( artery的名词复数 )；干线，要道

参考例句：

• Even grafting new blood vessels in place of the diseased coronary arteries has been tried. 甚至移植新血管代替不健康的冠状动脉的方法都已经试过。 来自《简明英汉词典》
• This is the place where the three main arteries of West London traffic met. 这就是伦敦西部三条主要交通干线的交汇处。 来自《简明英汉词典》

7 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

8 membranes   

n.（动物或植物体内的）薄膜( membrane的名词复数 )；隔膜；（可起防水、防风等作用的）膜状物

参考例句：

• The waste material is placed in cells with permeable membranes. 废液置于有渗透膜的槽中。 来自辞典例句
• The sarcoplasmic reticulum is a system of intracellular membranes. 肌浆网属于细胞内膜系统。 来自辞典例句