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   49169篇
  免费   3246篇
  国内免费   188篇
耳鼻咽喉   612篇
儿科学   1232篇
妇产科学   858篇
基础医学   6495篇
口腔科学   1252篇
临床医学   4771篇
内科学   9964篇
皮肤病学   725篇
神经病学   4796篇
特种医学   2552篇
外国民族医学   6篇
外科学   7220篇
综合类   593篇
一般理论   40篇
预防医学   4053篇
眼科学   1203篇
药学   2930篇
中国医学   69篇
肿瘤学   3232篇
  2023年   206篇
  2022年   348篇
  2021年   807篇
  2020年   613篇
  2019年   810篇
  2018年   951篇
  2017年   776篇
  2016年   918篇
  2015年   1051篇
  2014年   1471篇
  2013年   2047篇
  2012年   3105篇
  2011年   3301篇
  2010年   1871篇
  2009年   1714篇
  2008年   3069篇
  2007年   3157篇
  2006年   3120篇
  2005年   3048篇
  2004年   2856篇
  2003年   2776篇
  2002年   2662篇
  2001年   630篇
  2000年   586篇
  1999年   648篇
  1998年   604篇
  1997年   469篇
  1996年   424篇
  1995年   405篇
  1994年   326篇
  1993年   295篇
  1992年   384篇
  1991年   346篇
  1990年   317篇
  1989年   333篇
  1988年   297篇
  1987年   312篇
  1986年   289篇
  1985年   310篇
  1984年   311篇
  1983年   294篇
  1982年   323篇
  1981年   298篇
  1980年   264篇
  1979年   228篇
  1978年   233篇
  1977年   195篇
  1976年   170篇
  1975年   181篇
  1974年   184篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Fear of falling and postural control in Parkinson's disease.   总被引:4,自引:0,他引:4  
This study investigated the relationship between fear of falling (FOF) and qualitative and quantitative postural control in Parkinson's disease (PD). Fifty-eight nondemented PD patients were studied along with age-matched healthy controls. The degree of FOF was estimated using the Activities-specific Balance Confidence scale. Qualitative postural control was evaluated using a component of the Unified Parkinson Disease Rating Scale. Postural control was quantified, using centre of pressure measures obtained from a force plate, for eight standing balance tests of different challenges. The results showed that FOF was more evident for PD patients when compared with healthy individuals of similar age. Furthermore, FOF was significantly associated with a qualitative estimate of postural control in PD; individuals with PD who had a greater degree of posture impairment reported greater FOF. The results also showed that an estimate of FOF may help to explain quantitative postural instability in PD. FOF, when coupled with a qualitative estimate of postural control, was able to explain a greater amount of variation in quantitative balance performance for five of the eight balance tests. When considered independently, the qualitative measure of postural control, in general, could not well predict quantitative balance performance. The greater degree of FOF and its possible association with altered postural control suggests that FOF should be considered as an important, independent risk factor in the assessment and treatment of postural instability in patients with PD.  相似文献   
92.
The current study presents both longitudinal behavioral data and functional activation data documenting the effects of early focal brain injury on the development of spatial analytic processing in two children, one with prenatal left hemisphere (LH) injury and one with right hemisphere (RH) injury. A substantial body of evidence has shown that adults and children with early, lateralized brain injury show evidence of spatial analytic deficits. LH injury compromises the ability to encode the parts of a spatial pattern, while RH injury impairs pattern integration. The two children described in this report show patterns of deficit consistent with the site of their injury. In the current study, their longitudinal behavioral data spanning the age range from preschool to adolescence are presented in conjunction with data from a functional magnetic resonance imaging (fMRI) study of spatial processing. The activation results provide evidence that alternative profiles of neural organization can arise following early focal brain injury, and document where in the brain spatial functions are carried out when regions that normally mediate them are damaged. In addition, the coupling of the activation with the behavioral data allows us to go beyond the simple mapping of functional sites, to ask questions about how those sites may have come to mediate the spatial functions.  相似文献   
93.
The inclusion of disc-related disease of the cervical and lumbar spinal column in the Occupational Illness Ordinance with effect in law from 1 January 1993 brought with it a multitude of problems on a scal no-one could have foreseen for medical experts. At that time there were absolutely no conclusive criteria available to distinguish the many cases that were not specifically occupational in origin from cases that were classifiable as occupationally induced. Such criteria appeared to be urgently needed, especially as even considerable occupational stress on the spine is by no means sure to result in disease of the disc. The epidemiologically derived data gathered from disc-related diseases in specific occupational sectors alone have proved unsuitable for application as conclusive criteria of causation in individual cases as demanded by the legislator. The historical developments directed at solving the problems involved for those entrusted with providing expert opinions are presentd, as are the tentative approaches currently being followed.  相似文献   
94.
95.
The shear modulus of the vocal fold is an essential parameter required to enhance our understanding of how the vocal fold operates, to develop mathematical models of phonatation, and to provide benchmarks to quantify the effectiveness of surgical procedures. The authors announced the successful deployment of an instrument to measure vocal fold elasticity in vivo last year, and now present the data taken from eight patients in vivo. The shear modulus was measured at the mid-membranous point, in a transverse direction with respect to the axis drawn between the anterior commissure and vocal process. The range of mean shear modulus results is 701–2,225 Pa, with a mean value of 1,371 Pa.  相似文献   
96.
97.
98.
99.
100.
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