The patients aged 5.5-14 years old were divided into 2 groups. aged和old有一个即可，不应同时出现。可改为：

　　The patients aged 5.5-14 years were divided into 2 groups. 或

　　The patients，5.5-14 years old，were divided into 2 groups. 或

　　The patients 5.5-14 years of age were divided into 2 groups. 又如：

　　The patients of mean age 58 years old in the treatment group received interferon alpha injection，也不妥，可改为：

　　The patients in the treatment group, mean age 58 years, received interferon alpha injection.

　　7-day postnatal male Sprague-Dawley rats (n=51) were used for study. 可改为：Seven-day old male Sprague-Dawley rats (n=51) were used for study.

　　方法部分的时态也要用一般过去时。

　　结果

　　一般论文摘要中占篇幅较大的是这一部分。在这一段里介绍最主要的研究结果。时态用一般过去时。一般不主张用图表，可以介绍一些关键的数字。在摘要的'结果部分描述结果时，应当避免的一些情况：

　　The results of our study showed that …

　　It was shown that …

　　The present study showed that … 等等。

　　因为前面有个小标题Results，所以可以直接开始描述结果。

　　描述结果时最常遇到的问题是比较的句子。在组织句子时，应力求简练，避免重复、罗列太多的数字或罗嗦。

　　The mean ALT of group 1 patients was significantly higher than that of group 2 and 3 patients (p<0.01). 这样的描述是正确而流畅的，但改用下面的描述，则更简练：

　　The mean ALT level was higher in group 1 than in groups 2 and 3 (p<0.01).

　　注意，than 后面要有与比较项目相应的代词，that或those。单数用that, 复数用those。但比较的句子也可以不用带有than的句子，只用比较级，而后面用as compared to …。例如上面的句子：The mean ALT of group 1 patients was significantly higher as compared to group 2 and 3 (p<0.01). 这样的句子可在用了若干个带than的比较句子之后使用，换一个方式，免得太单调、重复。

　　国内作者常常写成如下句型：… and … of … group ... were …, …, respectively; … and … of … group ... were … and … These differences were statistically significant (p<0.05). 后面这句必要性不大，在前一句后附上P值即可。

　　下面是N Engl J Med一篇摘要中的结果部分：

　　Results The mortality rate was 30.8 percent in the placebo group and 24.7 cent in the drotrecogin alfa activated group. On the basis of the prospectively defined primary analysis, ment with drotrecogin alfa activated was associated with a reduction in the relative risk of death of 19.4 percent (95 percent confidence interval,6.6 to 30.5)and an absolute reduction in the risk of death of 6.1 percent (P=0.005).The incidence of serious bleeding was higher in the drotrecogin alfa activated group than in the placebo group (3.5 percent vs.2.0 percent, P=0.06). 这样的描述显得简捷、清楚，可读性强。

　　结论

　　这一部分一般用1~3句话。很多摘要只用一句话表示结论。例如下面的结论：Conclusion Patients who received their first CABG surgery without cardiopulmonary bypass had improved cognitive outcomes 3 months after the procedure, but the effects were limited and became negligible at 12 months.仅一句话，谓语动词用了一般过去时。又如：Conclusions Exercise capacity is a more powerful predictor of mortality among men than other established risk factors for cardiovascular disease. 也仅一句话，但谓语动词用了一般现在时。下面的例子有所不同：Conclusions Impaired glucose tolerance is highly prevalent among children and adolescents with severe obesity, irrespective of ethnic group. Impaired oral glucose tolerance was associated with insulin resistance while beta-cell function was still relatively preserved. Overt type 2 diabetes was linked to beta-cell failure. 这篇摘要的结论有三句。第一句用了一般现在时，说明糖耐量受损在重度肥胖儿童青少年中十分常见，虽然研究的样本不是很大(167名)。实际上在这种情况下用一般过去时也完全可以。但作者可能对这一结论的普遍性有较大把握。但后面2句均用了一般过去时。内容涉及葡萄糖耐量受损和显著的二型糖尿病的相关因素。

　　结论部分的写法，内容上要紧紧围绕或针对研究的目的和取得的结果叙述，不应扩大范围、慎重使用或不用推测的语句、也不应对研究本身进行评论或褒奖(这种作法在国内作者写的摘要中经常出现)。应当就事论事。至于对研究本身的意义或价值，应等待其他研究人员重复或有关部门进行评价、鉴定，而且这种鉴定或评价的结果也不是写进论文摘要中的内容。下面举几个有关的例子。