问题 单项选择题

中年男性。近2周前牙咀嚼疼痛,且牙龈肿胀有脓液流出,2年前该牙曾因龋坏而疼痛,未曾治疗。检查:残冠,近中邻面探及深龋洞,牙变色,叩诊有不适感,唇侧牙龈见一瘘管,有脓液溢出,X线片显示根尖有阴影。

如用桩冠修复该牙,冠桩的长度和宽度分别为()

A.长度为根长的2/3~3/4,宽度应为直径的1/3

B.长度为根长的1/2,宽度应为直径的1/3

C.长度为根长的1/3,宽度应为直径的2/3~3/4

D.长度为根长的2/3~3/4,宽度应为直径的1/2

E.长度为根长的1/2,宽度为直径的 2/3

答案

参考答案:A

阅读理解

阅读短文,根据其内容回答问题。

      Americans love sports — they love to play them, to watch them on television, and to talk about them. But

this hobby sometimes has serious results — at least to the players. For example, when people play tennis,

sometimes they hurt their elbow (肘部) and in this way they develop "tennis elbow". Also it is easy to hurt a

knee in a football game. These injuries (损伤) happen while the player is having fun, but they still hurt.

      A few months ago, Kathleen Simmons, who loves playing volleyball, hurt her knee in a volleyball game. Her

doctor told her that she needed a very difficult operation (手术) or she might not be able to play again. She felt

very sad and didn't know what to do.

      Then Simmons learned about "video operation". With the help of this new science in medicine, doctors can

now repair many injuries and get people back on the playing field and back to their jobs much faster. Simmons

found a hospital that was using this new science and went to see the doctor there. The doctors told her the

operation could help.

      For this operation, her doctor didn't have to open her knee. Instead he put a very small camera lens (镜头)

inside her knee. The lens sent back pictures, which appeared on a television screen. As he worked, he could see

the inside of her knee on the TV. With the help of the large pictures on the screen, the doctor knew exactly what

to do when he was making the repairs.

      Simmons started walking five days after her operation. "My knee hurt a lot the first few days," she said. "But

I felt better very quickly." Now, six months after her operation, Simmons can do everything she did before her

injury. "It feels like a new knee," she said. "I can even play volleyball again."

1. Do Americans love sports? 

    _____________________________________________

2. What sport is Simmons interested in?

    _____________________________________________

3. What did the doctor put inside Simmons' knee?

    _____________________________________________

4. What problem may people have when they play sports?

    _____________________________________________

5. What's the advantage (优点) of the new science?

    _____________________________________________

单项选择题