Literature retrieval should follow the principle of "four before four", that is, "near before far, inside before outside, professional before extensive, comprehensive before single article". It means that the publication time of documents should be as close as possible, so that the timeliness of articles is good; First inside and then outside is to look for domestic literature first, and then refer to foreign literature; It should be found that the contents of the literature are more professional and authoritative; The summary paper has been well summarized, which can save us the time to find the summary paper first.
Method/Step 2:
Professional medical network databases include: China Biomedical Literature Database (CBM), National Library of Medicine, Dutch Medical Abstracts Database (EMBase), American Chemical Abstracts (CA), International Pharmaceutical Abstracts (IPA) and Toxicology Database of National Library of Medicine (TOXLINE).
Method/Step 3:
Commonly used retrieval networks include: China Knowledge Network (CNKI), VIP Network, Wanfang Database, Superstar Electronic Library, China Sci-tech Periodical Database (NSTL), National Science and Technology Library and China Pharmaceutical Literature, as well as your university library, google, soopat, uspto, Daokebaba, Douding Network, Woodworm, Reading Show Account Network, Free Resource Network, Science Citation Index, Elsevier.