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   349663篇
  免费   25102篇
  国内免费   1469篇
耳鼻咽喉   3891篇
儿科学   8942篇
妇产科学   6202篇
基础医学   46798篇
口腔科学   6740篇
临床医学   35362篇
内科学   73733篇
皮肤病学   5120篇
神经病学   34744篇
特种医学   12357篇
外国民族医学   17篇
外科学   52218篇
综合类   4698篇
一般理论   391篇
预防医学   29167篇
眼科学   8230篇
药学   23718篇
  6篇
中国医学   464篇
肿瘤学   23436篇
  2023年   1875篇
  2022年   3407篇
  2021年   7415篇
  2020年   4464篇
  2019年   7140篇
  2018年   8197篇
  2017年   6127篇
  2016年   6939篇
  2015年   8139篇
  2014年   11650篇
  2013年   15840篇
  2012年   24183篇
  2011年   25125篇
  2010年   14313篇
  2009年   12828篇
  2008年   22142篇
  2007年   23422篇
  2006年   22857篇
  2005年   22764篇
  2004年   21357篇
  2003年   19627篇
  2002年   18655篇
  2001年   4008篇
  2000年   3462篇
  1999年   3997篇
  1998年   4219篇
  1997年   3534篇
  1996年   2968篇
  1995年   2881篇
  1994年   2418篇
  1993年   2195篇
  1992年   2433篇
  1991年   2260篇
  1990年   2040篇
  1989年   1970篇
  1988年   1867篇
  1987年   1785篇
  1986年   1801篇
  1985年   1806篇
  1984年   1895篇
  1983年   1701篇
  1982年   1907篇
  1981年   1750篇
  1980年   1541篇
  1979年   1232篇
  1978年   1171篇
  1977年   1015篇
  1976年   878篇
  1975年   811篇
  1974年   838篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
We targeted the MVNP gene to the OCL lineage in transgenic mice. These mice developed abnormal OCLs and bone lesions similar to those found in Paget's patients. These results show that persistent expression of MVNP in OCLs can induce pagetic-like bone lesions in vivo. INTRODUCTION: Paget's disease (PD) of bone is the second most common bone disease. Both genetic and viral factors have been implicated in its pathogenesis, but their exact roles in vivo are unclear. We previously reported that transfection of normal human osteoclast (OCL) precursors with the measles virus nucleocapsid (MVNP) or measles virus (MV) infection of bone marrow cells from transgenic mice expressing a MV receptor results in formation of pagetic-like OCLs. MATERIALS AND METHODS: Based on these in vitro studies, we determined if the MVNP gene from either an Edmonston-related strain of MV or a MVNP gene sequence derived from a patient with PD (P-MVNP), when targeted to cells in the OCL lineage of transgenic mice with the TRACP promoter (TRACP/MVNP mice), induced changes in bone similar to those found in PD. RESULTS: Bone marrow culture studies and histomorphometric analysis of bones from these mice showed that their OCLs displayed many of the features of pagetic OCLs and that they developed bone lesions that were similar to those in patients with PD. Furthermore, IL-6 seemed to be required for the development of the pagetic phenotype in OCLs from TRACP/MVNP mice. CONCLUSIONS: These results show that persistent expression of the MVNP gene in cells of the OCL lineage can induce pagetic-like bone lesions in vivo.  相似文献   
83.
84.
Experiments were performed to determine the effect of pin channel preparation with standard and reduction speed handpieces, and pin seating by hand and with motor drive. The greatest retention was achieved by preparation with a standard handpiece at 6000 rpm, and manual pin placement with a hand driver. The most consistent retention values were achieved using the reduction handpiece. All preparation and placement combinations examined produced a clinically acceptable result.  相似文献   
85.
86.
D. W. Barnes, D. A. Sirbasku & G. H. Sato, (eds.): Cell culture methods for molecular and cell biology. P. M. Gootman (ed.): Developmental neurobiology of the autonomic nervous system. M. Sandler, C. Feuerstein, B. Scatton (eds.): Neurotransmitter interactions in the basal ganglia. Harry M. Zimmerman (ed). Progress in neuropathology. M. Yahr & K. J. Bergmann (eds.): Parkinson's disease. G. Bock & M. O'Connor (eds.): Selective neuronal death. H. Julia Hannay (ed.): Experimental techniques in human neuropsychology. D. Papakostopoulos, S. Butler, I. Martin (eds.): Clinical and experimental neuropsychophysiology J. C. Rothwell: Control of human voluntary movement.  相似文献   
87.
88.
In a study of rock music preferences, listening/watching behavior, and views on destructive rock lyrics, 894 adolescents in grades 9 through 12 in rural, urban, suburban public, and metropolitan parochial schools were administered a questionnaire. Demographic information on parents was also collected. It was found that 17.5% of the students were fans of rock music with lyrics that promote homicide, suicide, or satanic practices (HSSR). Loglinear and multiple regression analyses were used to analyze the data. Parents' marital status, student sex, race, and school environment (urban, rural, suburban, etc.) were found to be significant predictors of HSSR status. As compared with non-HSSR fans, the HSSR fans were more likely to have parents who were “Never married” or “Remarried” and less likely to have parents in the “married” category. The HSSR fans were more likely to be male, white, and enrolled in urban schools but not parochial schools than expected; HSSR status also significantly predicted other music-related attitudes and behaviors. The HSSR fans reported liking both the sound and the lyrics of rock music more often than did non-HSSR fans, as did females and urban students. The HSSR fans more often felt that children under 10 years of age should be allowed to listen to HSSR lyrics, and they more frequently expressed the conviction that HSSR music does not affect adolescents' homicidal or self-destructive behavior. The HSSR fans and females reported more nearly complete knowledge of lyrics than did non-HSSR fans and males. The HSSR fans reported that they watch more MTV than did any other group except rural students.  相似文献   
89.
90.
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