首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Thousands of years ago man used handy rocks for his surgical operations. Later he used sharp bone or horn, metal knives and more
Thousands of years ago man used handy rocks for his surgical operations. Later he used sharp bone or horn, metal knives and more
admin
2015-06-23
62
问题
Thousands of years ago man used handy rocks for his surgical operations. Later he used sharp bone or horn, metal knives and more recently, rubber and plastic and that was where we stuck, in surgical instrument terms, for many years. 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, in time, 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, for a very large number of different complaints. The word "laser" means: light amplification by stimulated emission of radiation. As we all know, light is hot, any source of light — from the sun itself down to a humble match burning — 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 produce 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. No knives, no stitches, no unwanted damage — a true surgical wonder. Operations which once left patients exhausted and in need of long period of recovery time now leave them feeling relaxed and comfortable. So much more difficult operations can now be tried.
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. Altogether, tomorrow may see more and more information coming to light on the diseases which can be treated medically.
Which of the following is NOT a tool used for surgical operations before the 1960s?
选项
A、Bone.
B、Metal knives.
C、Scissors.
D、Rubber and plastic.
答案
C
解析
细节题。第一段前两句提到,数千年前,轻便的石头被用于外科手术中。之后,人类还使用了锋利的骨头或角、金属制的刀和塑胶。文中没有提到剪刀。故答案为C。
转载请注明原文地址:https://kaotiyun.com/show/jRl7777K
0
大学英语四级
相关试题推荐
ANewYorkTimes-CBSNewspollfoundthatalmost90percentofAmericansthinkthathomeownershipisanimportantpartoftheAm
ANewYorkTimes-CBSNewspollfoundthatalmost90percentofAmericansthinkthathomeownershipisanimportantpartoftheAm
Ifyouareayoungcollegestudent,mostofyourconcernsaboutyourhealthandhappinessinlifeareprobably【B1】______onthe
Ifyouareayoungcollegestudent,mostofyourconcernsaboutyourhealthandhappinessinlifeareprobably【B1】______onthe
Ifyouareayoungcollegestudent,mostofyourconcernsaboutyourhealthandhappinessinlifeareprobably【B1】______onthe
Ifyouareayoungcollegestudent,mostofyourconcernsaboutyourhealthandhappinessinlifeareprobably【B1】______onthe
Ifyouareayoungcollegestudent,mostofyourconcernsaboutyourhealthandhappinessinlifeareprobably【B1】______onthe
Thepointoffactoryfarmingischeapmeat,madepossiblebyconfininglargenumbersofanimalsinsmallspaces.Perhapsthegre
A、InPhilippineIslands.B、InpartsofAfrica.C、InChina.D、InRussia.C事实细节题。“InChina,clothandkniveswereused.”表明在中国,布匹
Thethousandsofpeopleforcedtoabandontheirhomesinrecentweekstofloodwatersarevictimsnotjustofnaturebutofhuman
随机试题
变压器温度的测量主要是通过对其油温的测量来实现的。如果发现油温较平时相同负载和相同条件下高出10℃时,应考虑变压器内发生了故障。 ()
a.thatmustbedoneb.anactiontakenagainstsomeoneinaccordancewiththelawc.aninsurerwhoiswell-knowninaparticul
患者,女性,24岁,已婚。因反复发作口腔溃疡3年、外阴溃烂3周余就诊。一年前曾患“结膜炎”,已治愈。无结核史,否认婚外冶游史。查体:上下唇黏膜、齿龈见数个米粒大小散在表浅性溃疡、周围红晕。背部见多个毛囊性炎性丘疹、丘疱疹及小结节。双侧小阴唇潮红、各见两枚绿
血沉减慢可见于
吊装方案的主要内容有()。
Shipping agents will( )the goods to be shipped.
企业采用类比法制订生产控制标准的依据有()。
某学生精力旺盛,争强好胜,做事勇敢果断,为人热情直率,其气质类型为多血质。()
亚洲国家躲过了近年来的全球大萧条,其中最主要的原因是它未被卷入2008年金融危机。然而近日一项调查显示,亚洲的债务水平正在以可怕的速度增长。从某些方面来说,这有部分合理理由,许多国家的超低息政策鼓励贷款,债务增长是财富增长的自然产物。但值得警惕的是,亚洲国
(think)______itover,hedecidedtogiveitup.
最新回复
(
0
)