问题 单项选择题

关于核医学放射性核素的选择,下列说法错误的是()

A.诊断性用药的放射性核素要有比较短的半衰期

B.为减少电离辐射对人体的危害,显像常用的核素γ射线能量小于100keV为好

C.治疗性用药目前多应用以发射β射线为主的核素

D.发射α射线类核素、俄歇电子类核素也可以用于核素治疗

E.治疗性用药的放射性核素要有比较长的半衰期

答案

参考答案:B

阅读理解

阅读理解。

     Peter wondered why he didn't have many friends. The reason was he was always taking, never giving.

     One day Peter told Bill, "I'd like to give a party on Saturday, I'd like you to come and bring Martha, too."

"Thanks, Peter. We'd be happy to come" "Perhaps you'd like to bring your violin. You and Martha sing well

together. I'm sure everyone will want you to sing for us."That was how Peter began to plan his party. Next

he asked another friend, Betty, to bring a cake."You make the best cake in the world, Betty, and I like to eat

your cake better than have one from the bakery."Peter invited a few other friends to come to his party. He

didn't forget to ask something from each one of them. He even asked Jim and Mary Jackson to let him give

the party at their house! 

     The party was a big success. However, as the guests were leaving, they said "Thank you" to Bill and

Martha for the music, Betty for tile cake, the Jacksons for the use of the house and to others for their hard

work. To Peter they just said, "Thanks for the invitation."

1. The party was held ________.

A. at Peter's house

B. in a large hall

C. at Peter's friend's house

D. in a secret place

2. Which of the following is not true?

A. Betty made the best cake.

B. Mary Jackson sang well.

C. Bill played the violin well.

D. The Jacksons did hard work for the party.

3. ________ liked Peter.

A. Many of his friends

B. Few people

C. Everyone

D. All his friends

4. Peter ________ to give the party.

A. tried his best

B. did nothing

C. only invited some friends

D. did everything

5. From the story, we can see Peter was ________.

A. a warm-hearted man

B. good at making friends

C. a selfish man

D. a welcomed friend

单项选择题