常见的病因A．胸膜炎B．肋骨骨折C．心脏停搏D．代谢性酸中毒E．大脑损害

男性，42岁，3天前体力劳动时突发心前区疼痛，2天来出现心悸气急，双下肢水肿，查体血压150/65mmHg，胸骨左缘3～4肋间可闻及Ⅳ级粗糙连续性杂音，可触及震颤，股动脉枪击音，最可能的诊断是（）

A.先天性室间隔缺损合并主动脉瓣关闭不全

B.主动脉窦瘤破裂

C.急性心肌梗死并发室间隔穿孔

D.动脉导管未闭合并心力衰竭

E.不稳定心绞痛

阅读理解

     When people lose legs after accidents or illnesses, emergency care and artificial limbs(假肢) often

allow them to walk again. Newts (蝾螈)in the same situation, on the other hand, can grow limbs back

their own! Scientists have known for a long time that certain animals can regrow limbs, but they haven't

quite figured out how these creatures do it.

     Researchers have now come up with some new ideas. Their work may give people the ability to

regrow lost limbs.  The researchers started with two simple experiments: when you cut a newt's leg at

the ankle, only the foot grows back; when you cut off a leg at the very end, the whole leg grows back.

  In both cases, the regrowth begins with stem cells.  Stem cells can develop into nearly any type of cell

in the body.

     How do a newt's stem cells know when to grow only a foot and when to regrow a whole leg?

     This question relates to another mystery. In newt's, a cutoff leg will grow back only if the nerve

bundle(神经束) in it also grows back, but if something prevents the nerve bundle from growing  the

stem cells at the wound won't  regrow a new leg.

     In its study, a British team focused on a protein called nAG.  When the team prevented nerves in

a limb from growing, but added the nAG protein to stem cells in the limb, the limb still regrew. That

protein seems to guide limb regrowth. People have proteins that are similar to nAG.  Further research

into these__materials may someday help human limbs recover by themselves.

1. A newt will regrow its leg if________.

A. its ankle was cut off but the nerve bundle was good

B. its leg was cut off and the nerve bundle stopped growing

C. its leg was cut off and the nerve bundle could grow back

D. its ankle and the nerve bundle could grow back

2. What do the underlined words "these materials"  refer to?

A. Nerve bundles and proteins.  

B. Proteins similar to nAG.

C. Stem cells and proteins.  

D. Stem cells and nerve bundles.

3. The first sentence of the passage________.

A. acts as a leadin

B. shows where researchers got their new ideas

C. states the author's opinion

D. describes the result of researchers' studies

4. What's the purpose of studying the newts?

A. To find out whether newts would regrow after being cutting off.

B. To find out the similarity between human and newts.

C. To find out what is nAG.

D. To find a way of helping human limbs recover by themselves.

阅读以下说明和C++代码，填充代码中的空缺，将解答填入答题纸的对应栏内。【说明】某应急交通控制系统（TraficControlSystem）在红灯时控制各类车辆（Vehicle）的通行，其类图如图5-1所示，在紧急状态下应急车辆红灯时也可通行，其余车辆按正常规则通行。下面的C++代码实现以上设计，请完善其中的空缺。

【C++代码】

某上市公司发行普通股1000万股，每股面值1元，每股发行价格5元，支付手续费20万元，支付咨询费60万元。该公司发行普通股计入股本的金额为______万元。

A．1000
B．4920
C．4980 D．5000

发电机电压达到规定的试验电压但尚无电流输出时的转速。在电流-转速特性曲线上，该点（）。

A.在横坐标上

B.在横坐标上方

C.在横坐标下方

D.在坐标零点