问题 单项选择题

关于青霉素类的描述正确的是

A.青霉素类的抗菌谱相同

B.各种青霉素均可口服

C.广谱青霉素完全可以取代青霉素G

D.青霉素只对繁殖期细菌有杀灭作用

E.青霉素对繁殖期和静止期均有杀菌作用

答案

参考答案:D

解析: 青霉素类除青霉素G为天然青霉素外,其余均为半合成青霉素。本类基本结构均含有母核-6-氨基青霉烷酸和侧链。母核为抗菌活性重要部分,侧链则主要与抗菌谱、耐酸、耐酶等药理特性有关。侧链不同,该类药物的抗菌谱、耐酸、耐酶等药理特性不同。青霉素抗菌机制抑制细菌细胞壁的合成,对已合成的细胞壁无影响,故对繁殖期细菌的作用较静止期强,只对繁殖期细菌有杀灭作用。

阅读理解

Whenever the house gets quiet, Mrs. Smith knows just where to find her 6-year-old daughter Maria: lost in the world of stories.

“I like to read every time of the day,” said Maria, a student at Creel Elementary School in Australia.

Maria’s headmaster, Mrs. White, wants each of her 850 students and their families to learn the love of reading this year. She wants reading at home to become an activity of choice in every family, even during holiday breaks. “I truly realize reading should be an important part of everyone’s life, and nothing should stop it.” said Mrs. White.

“The aim we want most of all is to help children understand they can enjoy reading, as well as practice their skills,” said Hannas, an education researcher. He suggested parents take their children to the library and allow them to pick out books that interest them.

Each night, students take home two books to read with their parents or other family members. They have to return the books the next day with a signed note from their parents showing that the books were read, and have passing tests that check how well they understand the books.

“We’re trying to get parents into the habit of reading with their kids.” said the headmaster. “Nothing is better than sitting on a sofa with your child and reading and laughing.”

Through books, Mrs. Smith, a parent, said she’s able to give her two daughters more experiences than she could.

“I think reading opens all the doors and creates imaginations in children,” she said, “I think if you read well, you can succeed in anything in life.”

小题1:The aim of the at-home-reading activity is to __________.

A.show the parents how important reading is

B.ask each of the students to learn from Maria

C.let parents care about their children

D.help the students and their families enjoy reading小题2:To make sure how well the students understand the books, the school has to ________.

A.give the students tests

B.ask their parents to write a note

C.return the books the next day

D.check how many books they have read小题3:From the article, we know that the at-home-reading activity __________.

A.can bring everything we want

B.has influenced the students at Creel Elementary School

C.helps family members understand each other better

D.makes parents understand school better

单项选择题