问题 单项选择题

铜绿假单胞菌导致角膜迅速溶解坏死的主要原因是()

A.铜绿假单胞菌生长速度快

B.角膜的微环境适合铜绿假单胞菌的生长

C.铜绿假单胞菌分泌的胶原酶降解角膜胶原纤维

D.引起了机体的抗原抗体反应

E.以上都不正确

答案

参考答案:C

解析:革兰阴性细菌角膜感染,多表现为快速发展的角膜液化性坏死。其中铜绿假单胞菌引起的感染具有特征性,该型溃疡多发于角膜异物剔除术后或戴接触镜引起的感染。也见于使用了被铜绿假单胞菌污染的荧光素纳溶液或其他滴眼液。起病迅速、发展迅猛,患者眼痛明显,严重的睫状充血或混合性充血,甚至球结膜水肿。主要原因在于铜绿假单胞菌产生蛋白分解酶,使角膜呈现迅速扩展的浸润及黏液性坏死,因此导致角膜快速溶解的原因选择C。

阅读理解

阅读理解

   It is very important to keep yourself in good health. When you are sick, you will neither be able to

study nor enjoy yourself. One of the factors(因素)leading to good health is to have a balanced diet.

 Remember,"You are what you eat."

   You should eat more fruits and vegetables which contain a lot of fibre (纤维).

   Try to eat less fried food and choose those are boiled, steamed, baked or stewed. You should also

cut down on oily, fatty and sugared foods and eat more food with carbohydrates (碳水化合物) such

as rice,bread and cereals for energy, especially if you have a more active lifestyle.

   The basic rule to remember is to include something from EVERY food group at each meal using the

suggested proportions (比例).

1. To stay healthy, one should _____.

A. eat whenever possible              

B. eat food that tastes good

C. keep a balanced diet              

D. diet to lose weight

2. According to the Pyramid Diet, we should eat more ____.

A. fish and chicken                  

B. meat and vegetables

C. butter and bread                  

D. bread and fruits

3. Carbohydrates provide our bodies with _____.

A. fibre        

B. energy  

C. oil        

D. water

4. _____ food should be eaten less.

A. Fried        

B. Boiled  

C. Baked        

D. Stewed

5. To keep a balanced diet, we should eat something _____.

A. whenever we want to              

B. in different proportions

C. that is delicious                  

D. in the correct proportions

单项选择题