按用途可将钢分为哪几类？

简述神经传导速度(NCV)和肌电图(EMG)对周围神经病的诊断价值。

（）年中国颁布了《中华人民共利国海洋环境保护法》。

阅读理解。

     Putting in water fountains (饮水器) at schools, and teaching children about the health

benefits of water, could reduce their risk of getting extra pounds, reports a new study that

is published in the latest issue of the journal Pediatrics.

      The findings are based on a survey in 32 elementary schools of two German cities, Dortmund

and Essen. The researchers, led by Rebecca Muckelbauer, a nutritionist(营养学家) at the

Research Institute of Child Nutrition Dortmund, weighed about 3,000 children, and asked

them about their beverage consumption(饮料消费量). 

     At the beginning of the school year, the experts had water fountains added to 17 of the schools.

The scientists also worked with teachers to carry out educational programs that promote the

benefits of drinking water. In contrast to schools in the United States, there are very few

schools in Germany that have water fountains.

     At the beginning of the study, there were no big differences in the number of overweight children

in the different groups. But by the end of the school year, children in the schools with water

fountains were 31 per cent less likely to gain extra pounds, compared to kids who went to other

schools, where water drinking was not encouraged.

      Children in the schools with fountains increased their water consumption from about 3 up to 4

glasses a day, while those in the other schools continued to drink an average of 3 glasses. Over

the research, the number of overweight kids upped from 384 to 385 out of 1,641 at the schools

with water fountains. In comparison, the number of overweight kids at the other schools increased

from 339 to 364 out of 1,309, Dr. Muckelbauer said.

      The experts cannot make any final conclusions and explain why the students who were encouraged

to drink water were less likely to gain extra weight. Dr. Muckelbauer noted that according to a few

other studies, drinking of water increases the rate at which calories are burned, while some other

research suggested that water may temporarily decrease appetite (食欲).

1. According to the passage, the journal Pediatrics _____.

A. may cover the subject of the health of children

B. mainly deals with the water drinking problem

C. is mainly about the mental health of kids    

D. must be a journal entitled by a school

2. What do we know about the survey from the passage?

A. The teachers were also encouraged to drink water.

B. The students surveyed were all overweight.

C. It surveyed children in the countryside.    

D. It lasted for a whole school year.

3. What can be learned from the last paragraph?

A. Drinking water certainly decreases appetite.

B. Further research is needed to support the finding.

C. The experts will encourage all the students to drink water.

D. Why students drinking more get less pounds will be clear soon.

4. What would be the best title for the passage?

A. Schools with water fountains          

B. Drink more water and become thinner

C. Water fountains at schools help kids stay thin

D. Water consumption at some German schools

光子线的平坦度和对称性以水模体中10㎝深Profile度处的中心多大射野范围确定（）

A.50％

B.60％

C.80％

D.90％

E.95％

大量气胸的体征包括

A．肋间隙增宽

B．双肺满布干啰音

C．气管向健侧移位

D．患侧叩诊过清音

E．语音震颤减弱