腰背剧痛伴高热、肢体运动障碍，最可能的疾病是（）。 A.腰椎结核 B.风湿热 C.化

The toxin produced by certain marine snails contains various proteins, one of which, when injected into mice, made mice aged two weeks or younger fall asleep and made older mice run for hiding places.
When mice are suddenly seriously threatened, very young ones react by staying perfectly still, whereas older ones run away.
The facts stated above provide the pest support for which of the following working hypotheses

A．The reaction of mice to sudden, serious threats is triggered by a chemical produced by the body, and this chemical is similar to the protein that was injected into the mice.

B．The protein contained in snail toxin that was injected into the mice ordinarily has the primary function of protecting snails by inducing in those snails complete immobility.

C．The protein that was injected into the mice would have made the mature mice fall asleep, too, if they had been injected with larger doses.

D．Very young mice are as likely to be exposed to sudden serious threats as are older mice.

E．(E) Very young mice are not developed enough to deal appropriately with even the stimuli that they are most likely to encounter.

小儿的体质特点有()

A．纯阳之体

B．稚阴稚阳

C．易虚易实

D．易寒易热

E．易夹痰瘀

有关系模式A(C，T，H，R，S)，其中各属性的含义是：
　　C：课程 T：教员 H：上课时间 R：教室 S：学生
　　根据语义有如下函数依赖集：
　　P=C→T，(H，R)→C，(H，T)→R，(H．S)→R
　　关系模式A的码是

A．C

B．(H，R)

C．(H，T)

D．(H，S)

一般认为证券市场是有效市场的机构投资者倾向于选择( )。

A．收入型证券组合
B．平衡型证券组合
C．指数化型证券组合
D．有效型证券组合

我国幼儿园的“双重”任务是指（）。

A.保育、教育儿童

B.为方便家长服务

C.获取经济效益

D.为儿童升入小学作准备