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   53569篇
  免费   4245篇
  国内免费   122篇
耳鼻咽喉   478篇
儿科学   1890篇
妇产科学   1199篇
基础医学   7428篇
口腔科学   877篇
临床医学   7194篇
内科学   9390篇
皮肤病学   937篇
神经病学   5476篇
特种医学   1368篇
外国民族医学   1篇
外科学   6043篇
综合类   798篇
一般理论   49篇
预防医学   6386篇
眼科学   869篇
药学   3924篇
  1篇
中国医学   100篇
肿瘤学   3528篇
  2023年   444篇
  2022年   719篇
  2021年   1494篇
  2020年   895篇
  2019年   1381篇
  2018年   1636篇
  2017年   1159篇
  2016年   1202篇
  2015年   1463篇
  2014年   1836篇
  2013年   2759篇
  2012年   3893篇
  2011年   4103篇
  2010年   2189篇
  2009年   1992篇
  2008年   3259篇
  2007年   3331篇
  2006年   3215篇
  2005年   3085篇
  2004年   2851篇
  2003年   2655篇
  2002年   2418篇
  2001年   811篇
  2000年   699篇
  1999年   655篇
  1998年   453篇
  1997年   363篇
  1996年   387篇
  1995年   288篇
  1994年   294篇
  1993年   252篇
  1992年   425篇
  1991年   434篇
  1990年   435篇
  1989年   401篇
  1988年   311篇
  1987年   327篇
  1986年   265篇
  1985年   295篇
  1984年   272篇
  1983年   229篇
  1982年   206篇
  1981年   154篇
  1980年   166篇
  1979年   203篇
  1978年   164篇
  1977年   132篇
  1976年   123篇
  1974年   150篇
  1973年   124篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
181.
There is an increasing clinical demand for HER2 analysis in breast cancer, especially since the release of trastuzumab. The authors assessed the ability of immunohistochemistry to detect HER2 overexpression in invasive mammary carcinomas (IMC) using five antibodies. Paraffin-embedded samples of 86 IMCs (T2N0) were used to compare the immunohistochemical overexpression of HER2 using two polyclonal antibodies (HercepTest [DAKO] and A0485 [DAKO]) and three monoclonal antibodies (CB11 from two different laboratories, Biogenex and Novocastra, and 4D5 [Genentech]). All immunostainings were scored according to the FDA-approved HercepTest recommendations. The HercepTest-positive cases were compared with gene amplification by FISH (Oncor Inform, Ventana). The HercepTest was positive in 31 of the 86 cases (36.1%). The DAKO antibody A0485 was positive in 25 of the 66 (37.8%). Monoclonal antibody 4D5 was positive in only 15 of the 86 cases (17.4%). There was almost total agreement in results between the two CB11 antibodies: 25 of the 86 positive cases (29.1%). All cases positive for CB11 or 4D5 were HercepTest positive. Most of the HercepTest 2+ cases were negative when using either monoclonal antibody. FISH was positive in 19 of the 20 HercepTest 3+ cases and negative in 5 HercepTest 2+ cases. Three CB11-2+ cases showed no amplification by FISH. In three FISH-positive cases the immunohistochemistry showed no overexpression by all antibodies used. These findings suggest that immunohistochemistry may be used reliably as a primary methodology for evaluating HER2; however, the use of polyclonal antibodies may not be adequate to assess HER2 overexpression. CB11, regardless of the manufacturer (Biogenex or Novocastra), showed better concordance with FISH (kappa=0.83) than did the polyclonal antibodies.  相似文献   
182.
183.
184.
Changing economic, political, environmental, and social conditions continue to have a cumulative impact on Australian regional communities, and in many instances, rural communities are being forced to initiate their own strategies in order to remain economically and socially viable. However, while communities respond in differing ways to similar change events, as do individuals, research examining the change process has largely been undertaken at the individual level. This article reports on an investigation of the characteristics that moderate a community's ability to manage change and the types of collective coping strategies communities employ to deal with change events. A model of community change process was used as the framework to examine the links between community characteristics, appraisal of change events (forest restructuring and tourism), and the use of collective strategies in three communities in Western Australia. Findings suggest that a community's mobilization of strategies is dependent on the collective assessment of the change event, the nature of the event, and the characteristics of the community. The implications for intervention through policy and community development are discussed briefly. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 201–216, 2004.  相似文献   
185.
186.
Although calcineurin inhibitors (CNIs) remain the mainstay of immunosuppression in liver transplantation (LTX), their long-term toxicity significantly contributes to morbidity and mortality. The elucidation of mechanisms of alloimmunity and leukocyte migration have provided novel targets for immunosuppression development. The toxicities of these agents differ from that of the CNI and act additively or synergistically. CNI avoidance protocols in LTX have not been achieved routinely; however, pilot trials have begun to delineate the limitations and promises of such approaches. CNI-sparing protocols appear to be much more promising in balancing the early need for minimizing rejection while tapering doses and minimizing long-term toxicity.  相似文献   
187.
188.
Schizophrenic psychopathology is heterogeneous and multidimensional. Various strategies have been developed over the past several years to assess and measure more accurately discrete domains of psychopathology. One of the more fruitful strategies to investigate more homogenous domains of psychopathology has been the positive-negative syndrome approach. However, this approach is unable to address a number of important issues. Most schizophrenics present a mixed syndrome; the criteria for what constitutes a positive and negative syndrome are variable; distinguishing primary from secondary negative symptoms can be difficult. In order to address some of these problems, we propose the introduction of a five syndrome model based on a reanalysis of factor analytic procedures used on 240 schizophrenics assessed with the Positive and Negative Syndrome Scale (PANSS). We present data on a 5-factor solution which appears to best fit the psychopathological data and which is supported by three independent and comparable factor analyses; negative, positive, excitement, cognitive and depression/anxiety domains of psychopathology give patients their individual mark. Data on internal consistency of the five factors and on initial validation using demographic and clinical variables are presented.  相似文献   
189.
190.
We report on a patient with interstitial deletion of 10q and compare her to 8 previously described patients, 2 of whom have chromosomal breakpoints similar to our patient. Minor anomalies including broad forehead, hypertelorism, strabismus, prominent philtrum, and “dysplastic” pinnae are present in our patient. Psychomotor retardation and hypotonia are universal findings in 10q interstitial deletion. Growth retardation, not present in our patient, is seen in some. These clinical findings are sufficiently distinct to suggest early chromosome studies. © 1992 Wiley-Liss, Inc.  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