2017-07-10 218阅读
不断的练习是提升雅思阅读水平的一大常见方法,同学们在备考阶段应找到难度恰当的阅读理解进行练习。希望以下内容能够对大家的雅思学习有所帮助!
TECHNOLOGY advances not only through new inventions, but also by the imaginative application of old ones. And one of the most ancient forms of scientific investigation, the post-mortem autopsy, may be ripe for just such a technological upgrade. According to a paper in this week’s Lancet, published by Ian Roberts of the John Radcliffe Hospital, in Oxford, it may soon be time to put away the scalpel and the retractor clamp, and to replace them with the body scanner.
The study of death is never a cheerful topic, but it has gone through a particularly gloomy patch over the past few decades. A recent tally by America’s Centres for Disease Control and Prevention showed that in 2007 only 8.5% of deaths in America were investigated by autopsy. In 1972 that figure was 19.3%. Britain’s coroners are more active, but perhaps not more accurate. Twenty-two percent of deaths in the United Kingdom lead to an autopsy. According to a government review, however, one in four is of miserable quality. The upshot in both cases is not just that the cause of individual deaths may be misascribed. More seriously, data about the processes of disease are lost, and those diseases are thus not as well understood as they might have been. Squeamish relatives of the deceased, too, often do not like the idea of bodies being cut up at the behest of coroners. Britain’s health department therore commissioned Dr Roberts to study whether scanning dead bodies in the way that is routine for living ones would help. His conclusion is that it would.
Rather than slicing the body with a knife, scanning slices them with radiation. Computerised tomography (CT) uses X-rays to collect information from many angles, and a lot of processing power to convert that information into cross-sectional images of a body’s inner tissues. In forensic cases CT scans are often used to spot fractures and haemorrhages. Dr Roberts found them adept at noticing diseased arteries, as well. The other widespread scanning technique, magnetic-resonance imaging (MRI), uses radio waves and is best suited for exploring the detail of soft tissues.
Though both of these technologies have been around for a long time, they have had only limited use in autopsies. America’s authorities conduct CT scans of dead soldiers—but such scans are employed to augment traditional post mortems, not replace them. Some coroners in England, spurred on by the religious objections of Jews and Muslims, do allow scans rather than conventional autopsies in certain cases. But the accuracy of these scans is unknown. Dr Roberts is the first to provide data on whether scanning might replace conventional methods.
Copyright 2000 - 2020 北京澳际教育咨询有限公司
www.aoji.cn All Rights Reserved | 京ICP证050284号
总部地址:北京市东城区 灯市口大街33号 国中商业大厦2-3层
高国强 向我咨询
行业年龄 11年
成功案例 2937人
留学关乎到一个家庭的期望以及一个学生的未来,作为一名留学规划导师,我一直坚信最基本且最重要的品质是认真负责的态度。基于对学生和家长认真负责的原则,结合丰富的申请经验,更有效地帮助学生清晰未来发展方向,顺利进入理想院校。
Tara 向我咨询
行业年龄 6年
成功案例 1602人
薛占秋 向我咨询
行业年龄 10年
成功案例 1869人
从业3年来成功协助数百同学拿到英、美、加、澳等各国学习签证,递签成功率90%以上,大大超过同业平均水平。
Cindy 向我咨询
行业年龄 18年
成功案例 4806人
精通各类升学,转学,墨尔本的公立私立初高中,小学,高中升大学的申请流程及入学要求。本科升学研究生,转如入其他学校等服务。