2. Literature index (secondary literature) processes, arranges and arranges the literature to form a systematic literature catalogue, that is, retrieval tools, such as catalogues and indexes, which are convenient for readers to find and use, and through it, the source of the original text can be found. 3 abstracts, monographs, progress, guides, manuals, etc. It is three documents, which are the systematic arrangement, selective generalization and analysis and synthesis of the original documents, making them more organized and explaining the problems more detailed and profound. 4. Bibliography and publication index recorded on CD-ROM are searched by computer and belong to four kinds of literature. According to the types of medical literature, it can be divided into teaching materials, reference books, monographs, magazines, periodicals, abstracts, reviews, academic conference papers and so on. Methods of medical literature retrieval: Manual retrieval or computer retrieval if possible. 1. Find the source of quoting the original text: trace back from papers, monographs, review textbooks and other references, find the source of quoting the original text, and consult authoritative and representative publications at home and abroad, from near to far. 2. Consult the periodical index. Most periodicals are published once a year, and original documents can be found once a year. 3. The retrieval abstracts are classified for easy reference. After finding the clue, you can further select the original document you want. For example, China Medical Abstracts 15, covering Chinese medicine, internal medicine, surgery, pediatrics, family planning, obstetrics and gynecology, otolaryngology, ophthalmology, dermatology, stomatology and hygiene, oncology, etc. , basic medicine, diagnostic radiology and nursing. Foreign Medicine consists of 46 volumes, which comprehensively introduces the new achievements, new technologies and new progress in various fields of foreign medicine in three forms: abstract, translation and abstract. It is an important information publishing system for learning foreign medical experience. 4. Using retrieval tools, such as China Science and Technology Information Catalogue (Medical Edition) and Foreign Science and Technology Information Catalogue (Medical Edition), manual retrieval can also be used for computer retrieval. Most scientific research institutions, medical colleges, medical centers and libraries in large and medium-sized hospitals with high computer popularization have established computer retrieval services. Due to the large number of files stored in the computer and the rapid retrieval of the use code, the online retrieval system is operated by professionals at present, and users do not need to operate buttons themselves. You can get the required documents by paying a certain fee. 5. Obtaining Personal Cumulative Cards Clinical medical researchers often consult relevant publications in their daily work to understand the new progress, and develop the habit of making cards, make a brief summary of their useful things, classify them, and consult them when necessary. 6. Ask an expert. Generally speaking, a medical expert and professor should always pay attention to the academic trends of his major, so sometimes he can point out which documents to find relevant information from.