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   408867篇
  免费   30246篇
  国内免费   10612篇
耳鼻咽喉   4357篇
儿科学   10025篇
妇产科学   7067篇
基础医学   30261篇
口腔科学   8654篇
临床医学   44000篇
内科学   46902篇
皮肤病学   5225篇
神经病学   20576篇
特种医学   9247篇
外国民族医学   37篇
外科学   39342篇
综合类   68239篇
现状与发展   25篇
一般理论   52篇
预防医学   39752篇
眼科学   5712篇
药学   37877篇
  632篇
中国医学   56694篇
肿瘤学   15049篇
  2024年   1664篇
  2023年   7013篇
  2022年   12553篇
  2021年   17069篇
  2020年   16224篇
  2019年   20573篇
  2018年   17974篇
  2017年   15659篇
  2016年   13309篇
  2015年   12404篇
  2014年   26191篇
  2013年   26587篇
  2012年   23990篇
  2011年   25601篇
  2010年   20597篇
  2009年   18223篇
  2008年   17225篇
  2007年   17842篇
  2006年   15324篇
  2005年   13213篇
  2004年   10749篇
  2003年   9431篇
  2002年   7380篇
  2001年   6640篇
  2000年   5488篇
  1999年   4633篇
  1998年   3762篇
  1997年   3571篇
  1996年   3057篇
  1995年   2870篇
  1994年   2736篇
  1993年   2135篇
  1992年   2167篇
  1991年   1889篇
  1990年   1669篇
  1989年   1455篇
  1988年   1379篇
  1985年   3836篇
  1984年   4838篇
  1983年   3359篇
  1982年   3832篇
  1981年   3575篇
  1980年   3186篇
  1979年   2919篇
  1978年   2540篇
  1977年   1918篇
  1976年   2157篇
  1975年   1636篇
  1974年   1432篇
  1973年   1280篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
粉防己碱对野百合碱致大鼠肺动脉构形重建的逆转作用   总被引:2,自引:0,他引:2  
以野百合碱复制Wistar大鼠肺动脉高压模型,用特殊染色方法观察粉防已碱对野百合碱致大鼠肺动脉构形重建的逆转作用,结果表明粉防已碱可选择性的降低野百合碱诱导的大鼠肺动脉高压的作用,并明显地逆转肺血管及肺组织损伤,降低肺动脉高压和右心室肥大,对体循环压力无影响  相似文献   
62.
超市连锁店熟食卤味销售的HACCP研究   总被引:2,自引:0,他引:2  
应用HACCP的原理和方法,对超市连锁店熟食卤味销售进行了危害因素分析,找出了关键控制点(CCP),提出了控制措施,并建议超市连锁店销售非包装熟食卤味时使用密封低温冷藏展示柜。  相似文献   
63.
中国女性的生殖健康权力   总被引:1,自引:1,他引:0  
<正> 中国的计划生育工作和人口控制的进程取得了举世瞩目的成就,中国妇女在这方面做出了巨大的贡献。在目前的生育调节工作中,妇女承担了几乎全部的生育调节和养育子女的责任及义务。社会、家庭甚至妇女本身都默认和接受了这种程式化的规范。  相似文献   
64.
Summary Twenty-two patients with recurrent or metastatic squamous cell carcinoma of the head and neck were treated with piroxantrone 150 mg/m2 intravenously every 21 days. There were no objective responses. The 95% upper confidence bound for response is 15%. Primary toxicity was hematologic.  相似文献   
65.
The present study evaluates the response comparability between 361 elderly hip fracture patients admitted from the community to seven Baltimore area hospitals between 1984 and 1986 and interviewer selected proxies on items pertaining to patients' pre-fracture health and functional status. Agreement across items ranges from very poor to good and varies with respect to the health or functional area assessed. Proxies tend to overestimate patient disability relative to the patients themselves, especially with regard to capacity to perform instrumental activities of daily living. Although proxies who report the greatest contact with patients respond most comparably to the patients, when they do disagree, proxies with the greatest patient contact tend to overestimate patient disability. The authors suggest that attention to item construction and phrasing may improve response comparability.  相似文献   
66.
Measurement of health-related quality of life was integrated into a randomized trial (NMSG 4/90) comparing melphalan/prednisone to melphalan/prednisone + interferon α-2b in newly diagnosed multiple myeloma. One of the aims of the study was to assess the prognostic significance of quality-of-life scores, using the EORTC QLQ-C30 questionnaire. Univariate analysis showed a highly significant association with survival from the start of therapy for physical functioning as well as role and cognitive functioning, global quality of life, fatigue and pain. In multivariate analysis, physical functioning and W.H.O. performance status were independent prognostic factors ( P values=0.001 for both) when analysed in a Cox regression model with the somatic variables β-2 microglobulin, skeletal disease and age. The best prediction for survival from the start of therapy was obtained by combining the β-2 microglobulin and physical functioning scores in a variable consisting of three risk factor levels with an estimated median survival of 17, 29 and 49 months, respectively. At a 12 months landmark analysis, the relative risk for patients with physical functioning score 0–20 v 80–100 was 5.63 (99% CI 2.76–11.49), whereas the relative risk for patients without an objective response to chemotherapy compared to those with at least a minor response was 2.32 (99% CI 1.44–3.74). Quality-of-life assessment may be an independent and valuable addition to the known prognostic factors in multiple myeloma.  相似文献   
67.
Newer policies of community care for those with disabilities have resulted in the home becoming the usual site of care. Policy makers must now give attention to the needs of those at home giving this care. This article explores the constraints on sociability opportunities of 73 mothers who were caring for children with disabilities. These opportunities are often built into leisure pursuits for women without caring responsibilities. However, choice of out-of-house leisure activity was circumscribed for the mothers in this study and their reported leisure activities revolved around home and neighbourhood. Even these sites offered limited scope for sociability because of the way in which caring affected domestic space and because of the characteristics of the modern Australian suburb. It is argued in this paper that personal time and personal domestic space are needed by care-givers so their sociability needs can be fulfilled. An understanding of the constraints imposed by use of the home as a place of care may make possible the planning of a rearrangement of domestic space to increase sociability opportunities for carers.  相似文献   
68.
PURPOSE: This study was undertaken to clarify the importance of bleeding vascular ectasia of the colon as the etiology of massive lower gastrointestinal hemorrhage in patients 40 years of age or younger. METHODS: An otherwise healthy 21-year-old male was admitted to a tertiary medical center with massive lower gastrointestinal hemorrhage. Technetium-labeled red blood cell scan, selective visceral angiography, and colonoscopy identified the source of bleeding as vascular abnormality of the descending colon. Segmental colonic resection was performed. RESULTS: Histologic review of the specimen demonstrated a vascular ectasia. The patient recovered uneventfully and has had no further stigmata of hemorrhage. A review of the literature was undertaken to make clear the significance of vascular ectasia as the source for massive colonic hemorrhage in the young adult. CONCLUSION: This is the first report that documents histologically a vascular ectasia as the source of massive lower gastrointestinal hemorrhage in an otherwise healthy patient less than 40 years of age. Vascular ectasia is an uncommon cause of lower gastrointestinal hemorrhage in the young adult.The Chief, Bureau of Medicine and Surgery, Navy Department, Washington, DC, Clinical Investigation Program sponsored this report #84-16-1968-532, as required by HSETCINST 6000.41A. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of Defense, or the United States Government.  相似文献   
69.
本文分析了460例胃癌胃粘膜活检资料,结果:男:女为2.36:1:51~60岁年龄组发病率最岛(37.17%);发生部位以胃窦部最多见,占46.74%;组织学分类以低分化腺癌最多,占51 52%;在伴随病变中,畅化生的检出率为21.74%,胃腺囊为35%,胃粘膜上皮异型增生为32.61%。本组材料提示,不完全性大肠型肠化生、异型胃腺囊及胃粘膜中度以上异型增生与胃癌有密切关系。  相似文献   
70.
74例小儿慢性头痛经辨证治疗,显效80.95%,好转16.67%,无效2.38%。痰浊头痛二陈汤或半夏白术天麻汤加减;肾虚头痛,杞菊地黄汤加减;淤血头痛,补阳还五汤;气血虚头痛八珍汤加减。指出了小儿内伤头痛的病因病机,并指出脑电图,脑阻抗血流图、CT、甲皱微循环可做为此病的诊断及疗效指标。  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