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   205183篇
  免费   3727篇
  国内免费   42篇
耳鼻咽喉   1347篇
儿科学   7795篇
妇产科学   3778篇
基础医学   20457篇
口腔科学   2017篇
临床医学   16306篇
内科学   36039篇
皮肤病学   1273篇
神经病学   19193篇
特种医学   9678篇
外国民族医学   11篇
外科学   31676篇
综合类   2900篇
一般理论   50篇
预防医学   22082篇
眼科学   3628篇
药学   11735篇
  1篇
中国医学   656篇
肿瘤学   18330篇
  2023年   204篇
  2022年   311篇
  2021年   631篇
  2020年   403篇
  2019年   711篇
  2018年   22559篇
  2017年   17768篇
  2016年   20017篇
  2015年   1564篇
  2014年   1694篇
  2013年   1985篇
  2012年   8802篇
  2011年   22858篇
  2010年   19668篇
  2009年   12353篇
  2008年   20969篇
  2007年   23215篇
  2006年   2092篇
  2005年   3657篇
  2004年   4857篇
  2003年   5654篇
  2002年   3698篇
  2001年   1007篇
  2000年   1128篇
  1999年   777篇
  1998年   512篇
  1997年   463篇
  1996年   328篇
  1995年   347篇
  1994年   310篇
  1993年   274篇
  1992年   515篇
  1991年   541篇
  1990年   555篇
  1989年   508篇
  1988年   432篇
  1987年   478篇
  1986年   389篇
  1985年   397篇
  1984年   310篇
  1983年   302篇
  1982年   196篇
  1981年   180篇
  1980年   199篇
  1979年   296篇
  1978年   232篇
  1975年   173篇
  1974年   207篇
  1973年   180篇
  1972年   175篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
42.
Conclusions  Noninvasive imaging of neurohumoral upregulation in remodeled myocardium suggests that an imaging strategy can be developed for predicting the rate of remodeling and likelihood of HF development. This should allow a more judicious use of neurohumoral antagonists especially in subjects who do not have manifest HF.74 In others specific targeted imaging may allow timely selection of individualized treatment strategies and ensure optimization of therapeutic intervention. Similar to ACE and AII receptors, multiple other targets in the hormonal cascades can identify the likelihood of adverse and favorable remodeling.74  相似文献   
43.
Clinicopathologic correlation of pigmented epiretinal membranes   总被引:1,自引:0,他引:1  
We performed clinicopathologic correlation on ten surgically removed pigmented epiretinal membranes causing macular pucker. All cases occurred in eyes with existing retinal holes or tears, including eight cases of macular pucker after previous retinal detachment. These cases probably represented a limited form of proliferative vitreoretinopathy. All membranes contained pigment epithelial cells with polarity, basement membrane, and melanosomes. Cytoplasmic melanin granules accounted for the clinical feature of pigmentation in these eyes.  相似文献   
44.
45.
Oral mucosal lichen planus (OMLP) is a well recognized mucosal disease with unknown etiology. Considerable controversy exists as to whether OMLP is intrinsically premalignant, or if the disorder facilitates the development of oral mucosal squamous cell carcinoma (OMSCC) by external factors. The aim of the present study was to investigate the expression of c-erbB-2 protein in the keratinocytes of initial biopsies of oral mucosal disorders diagnosed as OMLP with no evidence of epithelial dysplasia. and to compare the results with the expression of c-erbB-2 protein in subsequent biopsies obtained from the same patients. These results were compared with the findings from control groups (patients with dysplasia with no evidence of OMLP, patients with OMSCC with no evidence of OMLP and normal oral mucosa). The expression of the c-erbB-2 protein was evaluated by immunohistochemical staining of the gene product with the avidin-biotin-complex method using paraffin-embedded tissue sections. Five of the initial biopsies from patients with OMLP expressed the c-erhB-2 protein and one did not. None of the OMLP cases that subsequently showed evidence of dysplasia expressed the c-erhB-2 protein, and of the three OMSCC specimens from the patients with OMLP. two were negative and one expressed c-erbB-2 protein. The specimens from the control groups all expressed the c-erhB-2 protein. The results indicated the probability of the absence of c-erbB-2 staining being an indication of a potential for neoplastic transformation in OMLP with dysplastic changes.  相似文献   
46.
? The paper describes a multiproject practice development programme undertaken over a period of 1 year. ? The background and development of the programme are outlined, whilst attention is paid to the innovatory nature of the work, particularly the use of inductive, deductive and integrated approaches to both change implementation and project supervision. ? The programme was monitored throughout using different data sources and the paper uses evaluative material retrospectively to provide answers to organizational and professional difficulties which arose during the course of the programme. ? The authors conclude that the use of combinations of different models for practice development has potential, but requires careful supervision. ? They also recommend that those involved in practice development are made fully aware of its local or micropolitics, and develop strategies to deal with change before it occurs, not after it has taken place.  相似文献   
47.
The concept of need and the practice of needs assessment are both subject to a wide range of interpretations, to the likely detriment of individual assessments and to multidisciplinary working. Clear definition is important for individual assessment, for the development of multidisciplinary tools and in gathering planning information. The concept of need is clarified, firstly by distinguishing between need and the difficulties that engender it, and secondly through a taxonomy of need. These assist clear definitions of both need and needs assessment when linked with a consideration of the current help a person receives and a specification of the type of help required by a person to meet their needs. Such definitions have implications for the role of needs assessment in individual assessment, service evaluation, service management and planning and in the development of multidisciplinary needs assessment tools.  相似文献   
48.
49.
50.
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