问题 单项选择题

对血脑屏障的叙述正确的是()

A.血—脑脊液屏障是脑表面的动脉与脑脊液之间的屏障

B.维持脑血管压力的稳定

C.维持脑脊液成分的稳定

D.维持神经元微环境的稳定

E.血—脑屏障是血液与脑表面之间的屏障

答案

参考答案:D

填空题

阅读下则短文,然后在空白处写出适当的单词,单词首字母已给出。[有的词请注意词形的变化!]

    Young people are often unhappy when they are with their parents. They say that their parents don't

(1)u             them. They often think their parents are too strict (2)w             them. 

     Parents often find it difficult to win their (3)c             trust, and they seem to forget how they themselves

felt when they were young.

     For example, young people like to do things without much (4)t            . It's one of their ways to show

that they grow up and they can solve any difficult (5)p            . But older people always think (6)m             

than young people. Most of them plan things ahead and don't like their plans to be (7)c            , so when

you want your parents to let you do something, you will succeed easily if you ask before you really start

doing it.

    Young people often make their parents angry by the (8)c             they wear, the music they enjoy and

something else. But they don't mean to cause any trouble. They just want to be cut off (摆脱) from the old

people's world and they are (9)t             to make a new culture of their own. And if their parents don't like

their music or clothes or their ways of speech, the young people feel very sad. Sometimes instead of going

out with their parents, they just want to stay at home (10)a             and do what they like.

    If you plan to do something, you'd (11)b             win your parents over and get them to understand you,

if so, your parents will certainly let you do (12)w             you want to do.

单项选择题