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
2016-06-19
53
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/DEY7777K
0
大学英语四级
相关试题推荐
Gesturesaren’ttheonlyareainwhichtheunwarytravelercangettrippedup.Foreignculturesadheretodifferentbusinesscus
Papermoneyisusedeverydaybutpeopledonotoftenthinkofmoneyasjustpaper.Thisisbecausepeopleagreethatithasval
InBritainandothercountries,youngpeoplesometimestakea"gapyear",ayearoffbetweenhighschoolandcollege.Thisidea
Manyoftoday’scollegestudentsaresufferingfromaformofshock.Lisaisagoodexampleofastudentinshock.Sheisanatt
Intheearly20thcentury,fewthingsweremoreappealingthanthepromiseofscientificknowledge.Inaworldstrugglingwithr
Weoftenpassonlittlebitsofinformationtoourchildren,notknowingiftheyaretrue,andonlybecausetheywere【B1】_______
A、Theactorsandactressesonlyperformintheirowncommunities.B、Theactorsandactressesarenotpaidfortheirperformance.
Thousandsofyearsagomanusedhandyrocksforhissurgicaloperations.Laterheusedsharpboneorhorn,metalknivesandmore
Itwasoncethoughtthatairpollutionaffectedonlytheareaimmediatelyaroundlargecitieswithfactoriesandheavyautomobil
Thethousandsofpeopleforcedtoabandontheirhomesinrecentweekstofloodwatersarevictimsnotjustofnaturebutofhuman
随机试题
为2岁以下的婴儿进行肌内注射时,最好选用
临床广泛应用咪达唑仑的原因不包括
资金时间价值的习惯表达式是()。
在办理进境检疫审批手续后,检疫许可证的内容发生以下变化,货主或其代理人须重新办理检疫审批手续的有( )
衡量债券持有人按自己的需要和市场实际状况灵活地转让债券的难易程度的指标是()。
隋初展子虔开了“青绿山水”一派,后由唐代李思训、李昭道父子发展为“金碧山水”。()
对高中《工艺美术与现代设计艺术》[选自人美版社高中美术课程标准实验教科书《艺术欣赏》第二册第十二课,具体内容略]一课做教学设计。要求:(1)写出一篇要素完整的教学简案。(2)要明确本课的学习领域,恰当设定本课的教学目标、教学重点和难点。(3)合
国务院办公厅印发《关于开展2011年全国粮食稳定增产行动的意见》,明确提出了本年粮食生产的目标任务,其中包括全年粮食产量在一万亿斤以上,全力以赴争取实现连续第()个丰收年。
城镇体系多种多样,随不同的地理与经济因素而千差万别,但总体上可以分为四种类型,即金字塔型、多核型、网络型和带状型。以下中国的城镇体系中,属于带状型的是()。
2013年3月末,金融机构人民币各项贷款余额65.76万亿元,同比增长14.9%,增速比上年同期低0.8个百分点。2013年3月末,主要金融机构及小型农村金融机构、外资银行人民币小微企业贷款余额11.78万亿元,同比增长13.5%,比全部企业贷款
最新回复
(
0
)