问题 单项选择题

有关细胞因子的ELISA测定方法,下列说法正确的是()

A.ELISA方法可检测可溶性细胞因子

B.正常生理情况下,ELISA方法可检测出血清或血浆标本中的各种细胞因子浓度

C.测定的是细胞因子的生物活性

D.需要使用荧光素标记的细胞因子特异的单克隆抗体

E.可以测定单个细胞的细胞因子产生特性

答案

参考答案:A

解析:ELISA方法是目前临床最常用的细胞因子免疫测定方法,主要用于可溶性细胞因子的检测,其缺点是,测定的是细胞因子的免疫反应性,而不是细胞因子的生物活性。正常生理情况下,血循环中各种细胞因子的浓度极低,使用血清或血浆标本检测不出。酶联免疫斑点试验可检测单个细胞的细胞因子产生特性。所以只有A对。

阅读理解

阅读理解。

     One day, Tomas Jefferson, the president of the USA, was crossing a river with a group of travelers.

The river was overflowing its banks. So it was very dangerous to cross it on a horse. Each man was

fighting for his life! Then another traveler came and he wanted to cross it, too. But he didn't have a horse.

He watched the group and then asked Jefferson to take him. Jefferson agreed immediately. The man climbed

on. After they were both safe to the other side of the river, someone asked the man,"Why did you ask

present for help? Did you know him?" The man was shocked because he didn't know Jefferson was the

president. "All I know," he said, "on some of your faces were written the answer NO, but there was the

answer YES on his face."

1. Who was Tomas Jefferson?

A. He was a businessman.

B. He was a teacher.

C. He was a captain.

D. He was the president of the USA.

2. How did they cross the river?

A. In a boat.

B. On their horses.

C. By swimming.

D. By building a bridge.

3. When the group were crossing the river, _________.

A. water was flowing out of the river

B. it was windy and very cold

C. there were many empty boats in the river

D. everyone wrote a word on the face

4. At last, _________.

A. both Jefferson and the man were safe to cross the river

B. only Jefferson crossed the river

C. only the man crossed the river

D. Jefferson's horse died

5. From the passage, we know that _________.

A. all the travelers were kind

B. Jefferson was helpful

C. nobody knew the president

D. the man gave Jefferson some money

多项选择题