试题与答案

关于β-内酰胺酶,下列说法正确的是() A.它是由耐药菌株合成的一种钝化酶,可以作用

题型:多项选择题 X型题

题目:

关于β-内酰胺酶,下列说法正确的是()

A.它是由耐药菌株合成的一种钝化酶,可以作用于各种抗菌药物使其失效

B.青霉素酶属于β-内酰胺酶,可以打开青霉素分子结构中的β-内酰胺环,水解青霉素

C.氯霉素酶属于β-内酰胺酶,可以水解氯霉素

D.头孢菌素属于β-内酰胺酶,可以水解头孢菌素

E.β-内酰胺酶可以是细菌染色体编码,也可以是质粒编码

答案:

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    I did this for two years, but the lessons I learned have lasted a lifetime. I acquired

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balancing life's competing interests-in my case, school, homework and a job. This really

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    The hard work paid off. I attended the US Military Academy and went on to receive

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in everything else I've done, I have never forgotten those nights in the parking lot. The

experience taught me that there is dignity in all work and that if people are working to

provide for themselves and their families that is something we should honor.

1. Before my father got injured,we _____. [ ]

A. didn't like living in the USA

B. lived a poor but happy life

C. were lucky to move to the USA

D. had many ways to make money

2. When he recovered,to make a living my father _____. [ ]

A. ran a small shopping mall

B. did a part-time job

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3. Working in the parking lot for two years had taught me _____. [ ]

A. how to obey school discipline

B. how to do two things well at a time

C. that discipline and work were of equal value

D. that I must do as many things as possible at a time

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A. have done all kinds of jobs

B. are cleaning the parking lot

C. have achieved a lot in their lives

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