主题：道家武功学习记 -- 长河落日圆

Salt is as necessary to life as water. In many areas of Africa people once drank the urine of animals because they had no other source of salt. Without salt, human beings die.像水一样，盐是生命所必需的。在许多的非洲地区人们曾经喝过动物的尿液,因为他们没有其他盐的来源。没有盐,人会死亡。

The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. 人体需要血液中盐的含量保持不变。当身体不能获得足够的盐,它可以使尿液和汗水少排盐。但不能降低到零,要损失掉一些盐.

On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys and sweat glands. It then tries to adjust to this loss by speeding up its secretion of water. In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst.在完全无盐可食的地方,如非洲,身体通过肾脏和汗腺不断失去少量盐分。然后释放(分泌)水分来平衡盐损失。身体试图这样来保持血液中必需的盐含量。结果是身体缓慢干涸,最终死亡。因干渴而死亡。

In cases where there is little or no water to drink, the body tries to do the opposite thing. Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body’s normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.在没有或者很少有水可喝的情况下,身体试图要做的刚好相反。为了保持血液中盐含量不变,它试图阻止水离开身体,增排盐量。但和缺盐的情况一样,如果不能成功,水分还是损失掉了,人终究死于干渴。简而言之,盐和水同样重要,身体需要保持血液含盐量不变。

一般水生脊椎动物的体液盐分浓度大都达到海水的1/4至1/3上下