Directions: Revise the following sentences where necessary. Accumulating evidences exist that grape polyphenols work in 点我阅读全文
病例对照研究是按照有无所研究的疾病或某种卫生事件,将研究对象分为病例组和对照组,分别追溯其既往(发病或出现某种卫生事件前)所研究因素的暴露 临床研究方法-章节讨论 简答题 如何在pubmed中高特异性地检索随机对照试验?答案:文献检索的查全 点我阅读全文
For a paper, you need all the data before beginning the writing. 答案:错误 For a paper, every co-author needs to participate 点我阅读全文