既然阎老师点了我的名，那我就再多说几句关于乳房癌的话题。我不会因是哈佛的文章而退避。挟哈佛、挟洋文而令天下读者的时代已相去甚远了。

1） 首先，文章的题目就是讲乳房尺寸以及和左、右手僻与乳房癌的关系。乳房的尺寸是间接地用cup size来衡量、统计。摘要中没有一句提到乳房癌是由于戴胸罩而引起的。怎么到了阎老师的文章里就变成是戴胸罩会引起乳房癌？至于乳房尺寸和乳房癌的关联，我就不用多提了。阎老师一天要读十几小时的书，我相信这致癌机理阎老师一定能琢磨出来。

2） 文章只提及以上两因素可能和乳房癌有关（suggestive)，并没有肯定。P value只有一个是0.026，有意义的统计值，别的都没有达标。怎么到了阎老师的文章里就变成是有确凿的科学证据的？是否应该让男同学戴上胸罩试试，看乳房癌的发病率会不会有所提高？

3） 昨天给出的戴胸罩引发乳房癌的机理是因淋巴管被胸罩压迫、堵塞。那真是无稽之谈。“医生”和“南泥湾”引文中指出这原来是两位开夫妻老婆店的江湖术士般的人类学家提出的。毫无科学根据，是凭想象得出的结论。

4） 一个人的知识是非常有限的。不要说一天读十几小时的书、文章，就是一天读24小时的书和文章也不可能把所有的东西都看过来，更不要说理解、读明白了。所以读书、看文章时个人的思考、分析和判断比实际能读多少书、看多少文章更重要。

下文是阎老师引用的哈佛文章摘要的原文，同学们自己可以判断真伪：

Eur J Cancer. 1991;27(2):131-5. Links
Breast size, handedness and breast cancer risk.Hsieh CC, Trichopoulos D.
Department of Epidemology, Harvard School of Public Health, Boston, Massachusetts 02115.
Bra cup size and handedness were studied as possible risk factors for breast cancer. Data for 3918 cases and 11,712 controls from 7 centres were used to examine the association of handedness with laterality of breast cancer; data for 2325 cases and 7008 controls from 4 centres were used to assess the relation of bra cup size to breast cancer risk. There was a suggestive (P about 0.10) association of handedness with breast cancer laterality: odds ratio of a left-handed (or ambidextrous) woman having a left-sided cancer 1.22 (95% CI 0.96-1.56). Handedness may affect the lateral occurrence of breast cancer, although this tumour is in general more common in the left breast, possibly because this breast is usually slightly larger. Premenopausal women who do not wear bras had half the risk of breast cancer compared with bra users (P about 0.09), possibly because they are thinner and likely to have smaller breasts. Among bra users, larger cup size was associated with an increased risk of breast cancer (P about 0.026), although the association was found only among postmenopausal women and was accounted for, in part, by obesity. These data suggest that bra cup size (and conceivably mammary gland