GWD-10-9

usdream

我想问一下， 文中已经说了“infection by the SV40 virus is a contributing cause, since
in the United States 60 percent of tissue samples from mesotheliomas,“

现在说“E. In Finland, where the polio vaccine was never contaminated, samples from mesotheliomas do not contain SV40.“ 那么不久反对了文章的前提SV40 causes Mesotheliomas 吗？ 怎么能说是加强呢？

谢谢！

umclaire

usdream:

first, " infection by the sv40 virus is a contributing cause " is a stated fact; answer c, however just repeats this fact.

second, " infection by the sv40 virus" does not mean that the virus contracted by human comes from vaccine.

third, from E we can infer that vaccine is the only "possible"source.

luckyoldmi

the conclusion is that SV40 virus is a contributing cause.

the supportive evidence is that in the United States 60 percent of tissue samples from mesotheliomas contain SV40.

However, somebody may argue it is possible that SV40 is a derivative of mesotheliomas instead of the cause. Thus E ,which exclude the possibility of being dirivative supports the conclusion.

yanying76

c正确

e与题干中作者的结论（假设）无关：Researchers hypothesize that this vaccine was
the source of the virus found in mesotheliomas decades later.
Which of the following, if true, most strongly supports the researchers’ hypothesis?

micht

C is my answer...我的理解如下...

Researchers hypothesize that this vaccine was
the source of the virus found in mesotheliomas decades later

SV40 --> mesotheliomas
since some polio vaccine contaminated with convirus S40
Therefore, the question hypothesize that "polio vaccine is the source of the virus SV40 found in mesotheliomas"

C. Recently discovered samples of the vaccine dating from 1960 still show traces of the virus
Proves that polio vaccine still has virus S40

E. In Finland, where the polio vaccine was never contaminated, samples from mesotheliomas do not contain SV40.
polio vaccine, not contaminated with SV40, and mesotheliomas do not contain SV40==> 沒有contaiminated的polio vaccine是mesotheliomas的起因?

無法support polio vaccine是否是SV40的source

Thus, if C is true-->strengthen the hypothesis that polio vaccine may be the source of virus, SV40, found in mesotheliomas

[此贴子已经被作者于2004-9-25 5:52:52编辑过]

sh_eric77

I fully agree with unclaire, E is the best answer

ztlbox

以下是引用cloud0819在2004-9-4 15:35:00的发言：

Q9:
Although exposure to asbestos is the primary cause of mesothelioma, a slow-developing
cancer, researchers believe that infection by the SV40 virus is a contributing cause, since
in the United States 60 percent of tissue samples from mesotheliomas, but none from
healthy tissue, contain SV40. SV40 is a monkey virus; however, in 1960 some polio
vaccine was contaminated with the virus. Researchers hypothesize that this vaccine was
the source of the virus found in mesotheliomas decades later.
Which of the following, if true, most strongly supports the researchers’ hypothesis?
A. SV40 is widely used as a research tool in cancer laboratories.
B. Changes in the technique of manufacturing the vaccine now prevent
contamination with SV40.
C. Recently discovered samples of the vaccine dating from 1960 still show traces of the virus.

D. In a small percentage of cases of mesothelioma, there is no history of exposure to asbestos.
E. In Finland, where the polio vaccine was never contaminated, samples from mesotheliomas do not contain SV40.

我觉得C。E都是加强，如何区分？

这里涉及到一个问题：如果原文是从一个事实推出一个结论，那么强调这个事实的确是存在的构不构成加强？

C. Recently discovered samples of the vaccine dating from 1960 still show traces of the virus

首先，发现的virus有可能是后来污染的，还有，从现存的sample中发现virous也不一定意味着已用的vaccine中有virus

E. In Finland, where the polio vaccine was never contaminated, samples from mesotheliomas do not contain SV40.

排除了virus从其他途径来的可能，如果打了没被污染的疫苗，仍能检查出sv40，说明sv40肯定另有来源，相反，打了没被污染的疫苗，就检查不出sv40正说明污染的疫苗是sv40的唯一来源。

这是我们要加强的部分：

this vaccine was
the source of the virus found in mesotheliomas decades later.

richard_zhang

答案是E,排除其它可能性!

blur

同意E,大家还有什么意见？

mikeleven

E
C不过把题目的已知再说1次罢了。