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问题 单项选择题 A1/A2型题

HbBarts见于下列哪种疾病（）.

A.HbC

B.β珠蛋白生成障碍性贫血

C.α珠蛋白生成障碍性贫血

D.HbE

E.HbS

答案

参考答案：C

解析：珠蛋白基因缺失或基因缺陷导致一种或一种以上的珠蛋白肽链不能合成或合成不足，如α珠蛋白基因缺失，α链不能合成或合成不足，结果形成的HbH（β4）、HbBaIts（γ4）两种异常血红蛋白，都对氧有极高的亲和力，失去向组织释放氧的功能，而且极不稳定，易发生沉淀形成包涵体，导致溶血。

选择题

The children ran away________all directions the moment they caught sight of their teacher coming near. [ ]

A. in  

B. to

C. from  

D. off
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单项选择题

Are you a man or a mouse When people ask this question they want to know (1) you think you are a (2) person or a coward. But you will never really know the answer to this question (3) you are tested in real life. Some people (4) they are brave but when they come face to face with real (5) , they act like cowards. Others think of themselves as cowards, but when they meet danger, they act like (6)

Lenny had always thought of himself as a (7) person. He got worried before examinations. He worried about his job and health. All he wanted in life was to be safe and healthy. (8) , on January 15th, 2002, a plane crashed into the Potomac River in Washington. Lenny went to the river to see what was happening. He saw a woman in the (9) water. Lenny did not feel afraid. He kept very (10) and did a very dangerous thing. He jumped into the Potomac, (11) to the woman, and kept her head (12) the water. Seventy-eight people died that day. Thanks to Lenny, it was not (13) .

When you are in a very (14) situation and feel afraid, the body automatically produces a chemical in the blood. The chemical is called adrenalin. (15) adrenalin in the blood system, you actually feel per and per and are (16) to fight or run away. However, when you are absolutely terrified, the body can produce too much adrenalin. When this (17) , the muscles become very hard and you find you (18) move at all. You are then paralyzed with fear. This is (19) when we are very frightened, we sometimes say we’re "petrified". This word comes from the Greek word "petros", which means "stone". We are (20) frightened that we become stonelike.

5（）

A.life 

B.question 

C.mouse 

D.danger
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