电厂循环水系统有开式和闭式两种。开式的主要缺点是（）。A、需要的冷却水量十分庞大；

有关FSH和LH的叙述哪项是正确的（）

A.均为糖蛋白激素

B.由神经垂体分泌

C.由下丘脑分泌

D.作用于垂体

E.作用于下丘脑

青蛙的发育类型为______发育．

金庸的《射雕英雄传》中成功地塑造了两个人物——郭靖、杨康，这两人的名字与一历史事件有关，这一事件发生于（）

A．1125年

B．1127年

C．1276年

D．1279年

Something in chocolate could be used to stop coughs and lead to more effective medicines, say UK researchers.

Their study found that theobromine（可可碱）, found in cocoa, was nearly a third more effective in stopping coughs than codeine, which was considered the best cough medicine at present.

The Imperial College London researchers who published their results online said the discovery could lead to more effective cough treatment. “While coughing is not necessarily harmful it can have a major effect on the quality of life, and this discovery could be a huge step forward in treating this problem,” said Professor Peter Barnes.

Ten healthy volunteers were given theobromine, codeine or placebo, a pill that contains no medicine, during the experiment. Neither the volunteers nor the researchers knew who received which pill. The researchers then measured levels of capsaicin, which is used in research to cause coughing and as a sign of how well the medicines are stopping coughs.

The team found that, when the volunteers were given theobromine, the capsaicin needed to produce a cough was around a third higher than in the placebo group. When they were given codeine they needed only slightly higher levers of capsaicin to cause a cough compared with the placebo.

The researchers said that theobromine worked by keeping down a nerve activity(神经活动), which cause coughing. They also found that unlike some standard cough treatments, theobromine caused no side effects such as sleepiness.

小题1:According to Professor Barnes, theobromine ______.

A．cannot be as effective as codeine

B．can be harmful to people’s health

C．cannot be separated from chocolate

D．can be a more effective cure for coughs小题2:What was used in the experiment to cause coughing?

A．Theobromine.

B．Codeine.

C．Capsaicin.

D．Placebo.小题3:We learn from the text that volunteers in the experiment _____.

A．were patients with bad coughs

B．were divided into the three groups

C．received standard treatments

D．suffered little side effects小题4:Which of the following would be the best title for the text?

A．Codeine: A New Medicine

B．Chocolate May Cure Coughs

C．Cough Treatment: A Hard Case

D．Theobromine Can Cause Coughs