2015年考研英语阅读理解考前专项训练（38）
发布时间：2012/10/31 13:02:37 来源：城市网学院 编辑：admin
Since the late l970s，there has been lively debate about the possible connection between overhead power lines and childhood cancer.More specifically，researchers have been interested in the link，if any， between the extremely low frequency magnetic fields generated by these lines and childhood leukaemia.④ Studies on people have left more questions than answers， and laboratory experiments have failed to pin down a Dlausible mechanism whereby weak magnetic fields could trigger the disease.②In this context，a paper in this week's issue of the British Medical Journal may well spark alarm.But it shouldn't.
Gerald Draper and his colleagues at the University of Oxford，and John Swanson of National Grid Transc0，a Dower.transmission #pany，have looked at the distribution of childhood cancer along the Dower lines of the national electricity grid in England and Wales.The group analysed more than 2 9，000 cases of children with cancer against a #parable group without the disease.They found that children whose homes when they were born were within 200 metres of high—voltage lines appeared to have a 70％ higher risk of leukaemia——but not other cancers--than those who lived more than 600 metres from the lines.If living Bear power lines does increase the risk of cancer，the researchers reckon their result would account for about five of the more than 400 cases of childhood leukaemia that occur in England and Wales each year.④Even that small number is a big if.
Other studies that have shown a correlation between childhood leukaemia and power lines have done so onlv at smaller distances from the lines than Dr Draper's group.⑤Indeed，the researchers reckon the magnetic fields at the distances they considered are less than the average fields in homes--and fields of this level have been shown to have no effect.“We have no satisfactory explanation for our results in terms of causation by magnetic fields，and the findings are not supported by convincing laboratory data or any accepted biological mechanism”。they damply conclude.
Correlations are tricky things.Childhood leukaemia probably involves damage to DNA before birth. But that damage can be caused in many ways--infection，chemicals and ionizing radiation,for example. Despite Dr Draper's study，current evidence does not prove that living by high-voltage lines should be added to this list. [381 wordsl
1.By saying“a paper…may well spark alarm”，the author means that______.
A.the mechanism formulated in the paper is still plausible
B.the achievements introduced in the paper are unexpected
C.shocking influence of power lines might be revealed in the paper
D.readers should be welI prepared for the alarm before reading the paper
2.The researchers in Dr Draper's group______.
A.were most experts of fl power—transmission #pany
B.investigated more than 400 cases of childhood cancer
C.studied the power lines of the nationaI electricity grid
D.found a link between power lines and childhood leukaemia
3.The #ment“Even that small number is a big if”probably means that______.
A.the real number of cancer cases caused by power lines is negligible
B.the real number of cancer cases caused by power lines is much larger
C.1iving near power lines doesn't necessarily increase the risk of cancer
D.there are more cases of childhood leukaemis outside England and Wales
4.The author maintains that______.
A.any two things in the world might be correlated
B.the link between power lines and cancer is uncertain
C.strong magnetic fields are likely to trigger childhood cancer
D.there is no link between power lines and childhood leukaemia
5.It is implied in the text that the link between power lines and childhood leukaemia.examda.
A.there is little evidence to prove
B.Dr Draper's group has verified
C.a plausible mechanism can justify
D.further evidence is needed to support [NextPage] 难句透析
①More specifically，researchers have been interested in the link，if any，between the extremely low frequency ma9— netic fields[-generated by these lines]and childhood leukaemia.
【结构】介词短语“between…and…”是“link”的后置定语。“if any”是插入语。方括号所标示的过去分词短语“generated by these lines”是“magnetic fields”的后置定语，#。
【释义】更明确地说，研究人员一直关注这些高压线所产生的极低频磁场与儿童白血病之间的关系（如果有关系的话）。
②Studies on people have left more questions than answers，and laboratory experiments have failed tO pin down a plausible mechanism[whereby weak magnetic fields could trigger the disease].
【结构】本句是由逗号和“and”连接的两个分句组成的并列句。方括号所标示的“whereby…disease”是“mecha— nism”的后置定语从句。
【释义】对人群所做的研究与其说给出了答案，倒不如说发现了更多问题。实验室实验没有找到一种似乎合理的机制，可以用来解释为什么微弱磁场可能引发白血病。
③They found[that children（whose homes（when they were born）were within 200 metres of high—voltage lines） appeared tO have a 70％higher risk of leukaemia—but not other cancers than those（who lived more than 600 metres from the lines）].
【结构】方括号所标示的“that children…lines”是“found”的宾语从句。圆括号所标示的“whose homes…
lines”是“children”的后置定语从句，尖括号所标示的“when they were born”是其中的时间状语从句。圆括号所标示的“wh0…1ines”是“those”的后置定语从句。
【释义】研究人员发现，出生地距高压线不足200米，和那些出生地距高压线600米以外的儿童相比，他们患白血病（而非其他癌症）的几率高70％。
④[If（1iving near power lines）does increase the risk of cancer]，the researchers reckon[their result would account／or about five of the more than 400 cases of childhood leukaemia（that occur in England and Wales each year）J.
【结构】方括号所标示的“If…cancer”是条件状语从句，圆括号所标示的动名词短语“livin9…lines”是其中的主语。方括号所标示的“their result…each year”是“reckon”的宾语从句。圆括号所标示的“that occur…each year”是“cases”的后置定语从句。
【释义】如果居住地离高压线近确实增加了患癌症的几率，研究人员估计，在英格兰和威尔士每年出现的400多例儿童自血病中，他们的结果大约只能解释其中的5例。
⑤Other studies[that have shown a correlation between childhood leukaemia and power lines]have done SO[only at smaller distances from the lines than Dr Draper'S group].
【结构】方括号所标示的“that have shown…power lines”是“studies”的后置定语从句。方括号所标示的介词短语“0nly at…Dr Draper'S group”是主句的状语。
【释义】表明儿童白血病与高压线相关的其他研究也是这样做的，只不过，与德拉伯博士的研究小组相比，他们得出结论的距离还要短。
⑥Indeed，the researchers reckon[the magnetic fields at the distances（they considered）are less than the average fields in homes--and fields of this level have been shown tO have no effect].
【结构】方括号所标示的“the magnetic fields…no effect”是“reckon”的宾语从句。圆括号所标示的“they consid— ered”是“distances”的后置定语从句。破折号后面的部分是对“magnetic fields”的补充说明。
【释义】实际上，研究人员从所在地方测量的磁场强度要比患病儿童家中测量的磁场强度低——而且这种强度的磁场已经证明不会产生什么影响。 [NextPage] 全文翻译
20世纪70年代后期，人们对悬在高空的高压电线与儿童癌症之间的关系展开了激烈的辩论。更明确地说，研究人员～直关注这些高压线所产生的极低频磁场与儿童白血病之间的关系（如果有关系的话）。对人群所做的研究与其说给出了答案，倒不如说发现了更多问题。实验室实验没有找到一种似乎合理的机制，可以用来解释为什么微弱磁场可能引发白血病。
在这种情况下，本周刊登在《英国医学杂志》上的一篇文章也许可以找到一些突破。但这种情况不太可能出现。
杰拉尔德。德拉伯和他牛津大学的同事以及英国国家电力公司的约翰。斯万森一道调查了英格兰和威尔士境内国家电力线路儿童癌症发病率的分布情况。这个小组分析了29000多例患癌症的儿童的情况以及相同数量没患癌症孩子的情况。研究人员发现，出生地距高压线不足200米，和那些出生地距高压线600米以外的儿童相比，他们患白血病（而非其他癌症）的几率高70％。如果居住地离高压线近确实增加了患癌症的几率，研究人员估计，在英格兰和威尔士每年出现的400多例儿童自血病中，他们的结果大约只能解释其中的5例。
但是，这个小数目仍然是一个很大的假设。
表明儿童白血病与高压线相关的其他研究也是这样做的，只不过，与德拉伯博士的研究小组相比，他们得出结论的距离还要短。实际上，研究人员从所在地方测量的磁场强度要比患病儿童家中测量的磁场强度低——而且这种强度的磁场已经证明不会产生什么影响。他们草草地下了结论：就磁场引起的结果而言，我们没有找到满意的解释，而且研究结果得不到令人信服的实验室数据或任何广为接受的生物机制的支持。
相关性是不太可靠的。儿童白血病也许跟出生前的DNA损伤有关。但是这种损伤可能是很多途径造成的，比如感染、化学药物和致电离辐射。撇开德拉伯博士的研究不说，目前的证据并没有证明生活在高压电线旁边是造成儿童白血病的原因之一。
超纲词汇
leukaemia n.白血病，血癌
damply adv.潮湿地，衰减地
spark v.发火花，激发，引火
grid .高压输电网
reckon vt.计算，总计，估计，猜想
tricky adj.难处理的，棘手的，微妙的
plausible adj.似乎合理的，似乎可能的
causation n.因果关系
参考答案：1.C 2.D 3.C 4.B 5.D
