以原发性DNA损伤为检测终点的致突变试验是（） A.UDS试验 B.Ames试验 C

We’ve talked about snails (蜗牛) and their slow move. But much of the time snails don’t move at all. They are in their shells (壳) —sleeping.

Hot sun will dry out a snail’s body. So at the least sign of hot sun, a snail draws its body into his shell. A snail will die in a heavy rain. So when it rains, a snail does the same thing, too. A snail can sleep for as long as it needs to. It spends all the winter months in its shell, asleep.

In the spring the snail wakes up. Its body, about three inches long, comes out from the shell. When hungry, the snail looks for food. Its eyes, at the end of the top feelers (触角), are very weak. But its sense (感觉) of smell is very strong. It helps the snail to find food and the new greens.

A snail’s mouth is no bigger than the point of a pin (大头针). Yet it has 256,000 teeth! The teeth are very small, and you can’t see them. If you put a snail in a hard paper box, it will eat its way out! And if a snail wears out its teeth, it will grow new ones.

小题1: A snail _________.

A．moves more slowly at night

B．has thousands of feet

C．doesn’t move at all　　

D．sleeps much of the time小题2: In the sentence “A snail draws its body into its shell”, the word “draw” means _____.

A．to make with a pencil

B．to push

C．to pull

D．to move away小题3: From the story, we know _________.

A．a snail’s shell is very thin

B．a snail can’t see well

C．a snail’s nose is quite short

D．a snail’s body changes in different seasons小题4: A snail goes to sleep when _____.

A．it feels hungry

B．it is put into a paper box

C．spring is coming

D．it rains heavily小题5:Which of the following is wrong?

A．In winter the snail doesn’t eat or move.

B．A snail doesn’t like living under the sun

C．The snail’s teeth can’t be worn out.

D．The snail’s nose helps to find food.

下列哪项不属舌形改变

A．老嫩

B．胖瘦

C．裂纹

D．歪斜

某一船舶检验机构授权其一分支机构的工作权限为：

（一）负责船长小于60米或单机功率小于300kW的普通货船和特种货船，各类工程船舶，载客定额小于12人的旅游艇和工作艇，以及其它无特殊要求的船舶的图纸审查。

（二）负责各种类型的内河普通货船、工程船、特种货船，载客定额小于50人的客船，船长小于40米的非入级危险品船和油船，水上平台或水上设施，以及其它无特殊要求的船舶建造检验。

现该分支机构辖区内一船厂申请了一艘船长为53米，主机单机功率为378kW的船舶的建造检验并附送了该船的设计图纸要求审核，该分支机构是否可以受理该船的建造检验和图纸审查？如果可以则该如何正确操作该船图纸审查与建造检验？

患者，男，89岁。久病卧床，近日来冷汗自出，四肢厥逆，面色苍白，舌淡苔白，脉微欲绝。首选药组是（）

A.肉桂、桂枝

B.干姜、高良姜

C.附子、干姜

D.细辛、小茴香

E.吴茱萸、丁香

电磁阀容易出现哪些故障（）。

A.磁头过热

B.阀芯卡死

C.易损件磨损严重

D.过载