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问题 单项选择题 B1型题

用于最后孤立磨牙、且向近中舌侧或近中颊侧倾斜牙上的卡环是（）

A．对半卡环

B．圈形卡环

C．三臂卡环

D．回力卡环

E．联合卡环

答案

参考答案：B

解析：

三臂卡环用于牙冠外形好，无明显倾斜的基牙，属于标准的圆形卡环，应用最为广泛；回力卡环常用于后牙游离端缺失，基牙为双尖牙或尖牙，牙冠较短为锥形牙，减轻基牙的负荷，其应力中断的作用。

单项选择题 A1/A2型题

成人椎体结核与肿瘤X线片主要鉴别点是（）

A.椎体破坏程度

B.椎间隙是否变窄或消失

C.死骨形成

D.椎旁软组织阴影

E.以上都是
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问答题

The proportion of works cut for the cinema in Britain dropped from 40 percent when I joined the BBFC in 1975 to less than 4 percent when I left. But I don’t’ think that 20 years from now it will be possible to regulate any medium as closely as I regulated film.
The Internet is, of course, the greatest problem for this century. (46) The world will have to find a means, through some sort of international treaty or United Nations initiative, to control the material that’s now going totally unregulated into people’s homes. That said, it will only take one little country like Paraguay to refuse to sign a treaty for transmission to be unstoppable. Parental control is never going to be sufficient.
(47) I’m still very worried about the impact of violent video games, even though researchers say their impact is moderated by the fact that players don’t so much experience the game as enjoy the technical maneuvers that enable you to win. But in respect of violence in mainstream films, I’m more optimistic. Quite suddenly, tastes have changed, and it’s no longer Stallone or Schwarzenegger who are the top stars, but Leonardo Di Caprio--that has taken everybody by surprise.
(48) Go through the most successful films in Europe and America now and you will find virtually none that are violent. Quentin Tarantino didn’t usher in a new, violent generation, and films are becoming much more pre-social than one would have expected.
Cinemagoing will undoubtedly survive. The new multiplexes are a glorious experience, offering perfect sound and picture and very comfortable seats, things which had died out in the 1980s. (49) I can’t believe we’ve achieved that only to throw it away in favour of huddling around a 14-inch computer monitor to watch digitally-delivered movies at home.
It will become increasingly cheap to make films, with cameras becoming smaller and lighter but remaining very precise. (50) That means greater chances for new talent to emerge, as it will be much easier to learn how to be a better film-maker. Careers will be shorter in the future, and once retired, people will spend a lot of time learning to do things that amuse them--like making videos. Fifty years on we could well be media-saturated as both producers and audiences: instead of writing letters, one will send little home movies entitled My Week.
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