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Thousands of years ago man used handy rocks for his surgical operations. Later he used sharp bones or horns, metal knives and mo
Thousands of years ago man used handy rocks for his surgical operations. Later he used sharp bones or horns, metal knives and mo
admin
2023-03-13
67
问题
Thousands of years ago man used handy rocks for his surgical operations. Later he used sharp bones or horns, metal knives and more recently, rubber and plastic. In the 1960s a new tool was developed, one which was, first of all, to be of great practical use to the armed forces and industry , but which was also to revolutionize the art and science of surgery.
The tool is the laser and it is being used by more and more surgeons all over the world. As we all know, light is hot, and any source of light will give warmth. But light is usually spread out over a wide area. The light in a laser beam, however, is concentrated. This means that a light with no more power than that produced by an ordinary electric light bulb becomes intensely strong as it is concentrated to a pinpoint-sized beam.
Experiments with these pinpoint beams showed researchers that different energy sources pro-duce beams that have a particular effect on certain living cells. It is now possible for eye surgeons to operate on the back of human eye without harming the front of the eye, simply by passing a laser beam right through the eye-ball. Operations which once left patients exhausted and in need of long period of recovery time now leave them feeling relaxed and comfortable.
The rapid development of laser techniques in the past ten years has made it clear that the future is likely to be very exciting. Perhaps some cancers will be treated with laser in a way that makes surgery not only safer but also more effective.
What do we find after the development of the laser in the 1960s?
选项
A、Industrial revolution brought surgery changed greatly.
B、Medical help became available for industrial workers.
C、The study of art went through a complete revolution.
D、Human being’ s methods in surgery changed greatly.
答案
D
解析
事实细节题。题干的意思是“20世纪60年代激光取得发展后我们可以发现什么?”根据原文第一段最后一句可知“激光为外科手术带来革命性的变化”,故选D。
转载请注明原文地址:https://kaotiyun.com/show/nZ0D777K
本试题收录于:
公共英语二级笔试题库公共英语(PETS)分类
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公共英语二级笔试
公共英语(PETS)
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