首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2350748篇
  免费   171283篇
  国内免费   3331篇
耳鼻咽喉   32050篇
儿科学   75903篇
妇产科学   62714篇
基础医学   348241篇
口腔科学   63634篇
临床医学   211413篇
内科学   457376篇
皮肤病学   51893篇
神经病学   185331篇
特种医学   88033篇
外国民族医学   489篇
外科学   353890篇
综合类   47510篇
现状与发展   12篇
一般理论   848篇
预防医学   182760篇
眼科学   54328篇
药学   175120篇
  11篇
中国医学   4576篇
肿瘤学   129230篇
  2021年   18995篇
  2019年   19544篇
  2018年   27064篇
  2017年   20361篇
  2016年   22753篇
  2015年   25649篇
  2014年   36114篇
  2013年   53975篇
  2012年   74704篇
  2011年   79427篇
  2010年   47067篇
  2009年   44575篇
  2008年   74632篇
  2007年   79507篇
  2006年   80308篇
  2005年   77808篇
  2004年   74389篇
  2003年   71721篇
  2002年   69394篇
  2001年   108754篇
  2000年   111463篇
  1999年   93509篇
  1998年   26995篇
  1997年   23667篇
  1996年   24059篇
  1995年   22719篇
  1994年   20898篇
  1993年   19717篇
  1992年   72010篇
  1991年   70087篇
  1990年   68409篇
  1989年   65694篇
  1988年   60318篇
  1987年   59140篇
  1986年   55231篇
  1985年   53015篇
  1984年   39322篇
  1983年   33397篇
  1982年   19860篇
  1979年   35872篇
  1978年   25652篇
  1977年   21233篇
  1976年   20334篇
  1975年   21823篇
  1974年   26160篇
  1973年   24806篇
  1972年   23204篇
  1971年   22039篇
  1970年   20248篇
  1969年   19319篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
993.
994.
An endoscopic endonasal approach was performed to remove an intra-suprasellar Rathke's cleft cyst. Rathke's cleft cyst are benign lesions, rarely diagnosed because they are often asymptomatic. To the best of our knowledge, at least 475 cases of Rathke's cleft cysts have been reported. They seem to arise from remnants of Rathke's pouch, an invagination of the stomodeum. A 52-year-old woman, complaining of bilateral frontal headaches, was operated on by using an endoscopic endonasal approach, for an intra-suprasellar tumor. The pre-operative diagnosis was non-functioning pituitary adenoma. Intra-operatively a creamy-coloured viscous tissue was found. After the removal of the cyst contents and of the capsule, the suprasellar structures were seen well. The chiasmatic cistern, the chiasm, the pituitary stalk and the pituitary gland were visualized with 0 and 30 degree endoscopes. The pathological findings showed a well-differentiated cuboidal epithelium. The diagnosis was Rathke's cleft cyst. No post-operative complications were observed. The endoscopic technique was particularly suitable in this case, both for the Rathke's cleft features and for an excellent outcome. The Rathke's cleft cyst was easily removed by suction and the cyst wall was entirely removed with curettes and pituitary punches. The hypophysis was distinguished from the cyst and was preserved. The surgical manoeuvres were all done under direct visual control. The absence of nasal packing and of breathing difficulties made comfortable the post-operative outcome. Thus, the endoscopic endonasal approach can be considered the favourite technique in case of either intra- and/or suprasellar Rathke's cleft cysts.  相似文献   
995.
996.
OBJECTIVE: Traditional assessments of the microbial flora associated with acute bacterial rhinosinusitis have relied on maxillary sinus punctures (taps) and culture. These taps are now considered the gold standard for obtaining cultures and are used as the method of identifying bacterial pathogens in antimicrobial trials. Maxillary sinus taps are limited by discomfort to the patients and technical concerns. Because of these factors, the standard of performing taps has limited antibiotic trials and microbial surveillance. Alternatives to maxillary sinus taps have been explored. STUDY DESIGN: We conducted a retrospective, systematic review of the literature from 1950 to 2000 of articles comparing culture techniques in the nose and paranasal sinuses for acute bacterial rhinosinusitis. RESULTS: Nasal cultures have poor correlation to maxillary sinus cultures, whereas there is 60% to 85% concordance between endoscopically guided middle meatal cultures and maxillary sinus cultures. These studies, however, are all limited by small sample sizes and therefore are inadequate to make any concrete recommendations regarding the relative role of endoscopically guided middle meatal cultures as a formal method of pathogen identification in acute bacterial rhinosinusitis. CONCLUSION: A formal prospective study with sufficient sample size to assess the concordance between the microbial flora of the maxillary sinus punctures and middle meatal cultures in acute rhinosinusitis is recommended.  相似文献   
997.
THE BASIC SCIENCE OF PSYCHOLOGY HAS IDENTIFIED specific ingrained responses that are fundamental elements of human nature, underpin common influence strategies and may apply in medical settings. People feel a sense of obligation to repay a perceived debt. A request becomes more attractive when preceded by a marginally worse request. The drive to act consistently will persist even if demands escalate. Peer pressure is intense when people face uncertainty. The image of the requester influences the attractiveness of a request. Authorities have power beyond their expertise. Opportunities appear more valuable when they appear less available. These 7 responses were discovered decades ago in psychology research and seem intuitively understood in the business world, but they are rarely discussed in medical texts. An awareness of these principles can provide a framework for physicians to help patients change their behaviour and to understand how others in society sometime alter patients' choices.  相似文献   
998.
999.
Hypersensitivity reactions may occur during antituberculous chemotherapy. Severe reactions are rare, and in the three years 1983-86 during which we have both worked in Africa managing large numbers of patients with tuberculosis we only saw one or two cases with severe and generalised cutaneous hypersensitivity. In the last 12 months, however, there have been a number of cases with severe Stevens-Johnson syndrome which developed during antituberculous chemotherapy and has invariably been associated with seropositivity to HIV (human immunodeficiency virus).  相似文献   
1000.
Hemorrhage following mandibular osteotomies: a report of 21 cases   总被引:1,自引:0,他引:1  
Hemorrhage associated with mandibular osteotomies, especially to the extent that it becomes life threatening, is a rare occurrence and its risk is less than that following maxillary orthognathic surgery. Twenty-one cases of significant bleeding following mandibular sagittal split ramus osteotomies, vertical and oblique ramus osteotomies, and genioplasties are presented. Life-threatening hemorrhage associated with mandibular osteotomies is primarily an intraoperative problem and the incidence of major postoperative and recurrent hemorrhage is not as great as following maxillary osteotomies. Suggestions for the avoidance and treatment of these bleeding complications are discussed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号