问题 单项选择题 B型题

当接触铅作业人员处于慢性铅中毒期时,主要应该提供何种膳食()

A.多钙少磷的成碱性食品

B.低钙多磷的酸性食品

C.正常膳食

D.高钙高磷膳食

E.成酸性食品和成碱性食品的交替使用

答案

参考答案:B

解析:1.膳食钙的摄入量,对铅中毒者有着重要影响。当血钙增高,体液趋向碱性,血液中的铅将形成不溶性磷酸三铅而沉积在骨骼中,对机体暂时不呈毒性。因此,急性铅中毒期,主要应供给高钙低磷的成碱性膳食,促使铅在骨骼中沉积。 2.膳食钙的摄入量,对铅中毒者有着重要影响。当血钙降低、体液趋向酸性,沉积在骨中的铅会形成磷酸氢铅而易于从骨骼中游离入血液,排出体外。因此,慢性铅中毒者应供给低钙高磷的酸性食物,以促进沉积在骨中的铅游离入血,促进排泄。

阅读理解

Maybe everyone likes dogs, and almost everyone likes to read stories about dogs.

  I have a friend. He has a large police dog named Jack. Police dogs are very clever. Every Sunday afternoon my friend takes Jack for a long walk in the park. Jack likes these long walks very much.

  One Sunday afternoon a young man came to visit my friend. He stayed a long time. He talked and talked. Soon it was time for my friend to take Jack for his walk. But the visitor still stayed. Jack became very worried. He walked around the room several times and then sat down in front of the visitor and looked at him. But the visitor paid no attention to Jack. He went on talking. At last Jack got angry. He went out of the room and came back a few minutes later. He sat down again in front of the visitor, but this time he took the visitor’s hat in his mouth. The visitor saw it and was surprised. He laughed and left.

小题1:--The young visitor stayed a long time, didn’t he?

  --_____.

A.Yes, he didn’t

B.No, he didn’t

C.Yes, he did

D.No, he did小题2:Jack became worried because _____.

A.he wanted to go out for a walk

B.he wanted to play with him

C.he didn’t know the young man

D.he wanted to eat something小题3:Jack sat down in front of the visitor because _____.

A.he wanted the visitor to talk to him

B.he wanted to talk with the young man

C.he wanted to show the visitor how clever he is

D.he wanted the visitor to leave小题4:The visitor went on talking and _____.

A.he paid no attention to his hat

B.he paid no attention to Jack

C.he didn’t know that his hat was taken away by Jack

D.he didn’t like Jack小题5:Jack went out of the room, but came back with _____ in his mouth.

A.food

B.nothing

C.something

D.the visitor’s hat

选择题