问题 问答题 简答题

说明水利尿和渗透性利尿有何区别?

答案

参考答案:

水利尿:一次饮入大量清水,引起血浆晶体渗透压↓→对下丘脑视上核和室旁核周围渗透压感受器刺激减弱→神经垂体释放抗利尿激素↓→减少集合管对水的重吸收量→尿量↑。

渗透性利尿:小管液中溶质的浓度增加使渗透压升高,水的重吸收减少而引起尿量增多的现象称为渗透性利尿。

因此,两者的结果都是多尿但区别在于利尿机制不同,水利尿需要通过神经-体液因素参与调节的结果,而渗透性利尿无需神经-体液因素参与,属肾内自身调节的一种现象。

选择题
阅读理解

A couple from Miami, Bill and Simone Butler, spent sixty –six days in a life-raft (救生艇) in the seas of Central America after their boat sank.

Twenty-one days after they left Panama in their boat, Simony, they met some whales (鲸鱼). “They started to hit the side of the boat,” said Bill, “and then suddenly we heard water.” Two minutes later, the boat was sinking. They jumped into the life-raft and watched the boat go under the water.

For twenty days they had tins of food, biscuits, and bottles of water. They also had a fishing-line and a machine to make salt water into drinking water— two things which saved their lives. They caught eight to ten fish a day and ate them raw (生的). Then the line broke. “So we had no more fish until something very strange happened. Some sharks (鲨鱼) came to feed, and the fish under the raft were afraid and came to the surface. I caught them with my hands.”

About twenty ships passed them, but no one saw them. After fifty days at sea their life-raft was beginning to break up. Then suddenly it was all over. A fishing boat saw them and picked them up. They couldn’t stand up. So the captain carried them onto his boat and took them to Costa Rica. Their two months at sea was over.

68. Bill and Simone were traveling ______ when they met some whales.

A. in a life-raft    B. in Miami     C. in Simony     D. in Panama

69. During their days at sea, ______ saved their lives.

A. tins of food and bottles of water    B. a fishing-line and a machine

C. whales and sharks               D. Twenty passing ships

70. After their boat sank, the couple ______.

A. jumped into the life-raft          B. heard water

C. watched the boat go under water   D. stayed in the life-raft