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   2699527篇
  免费   195099篇
  国内免费   5969篇
耳鼻咽喉   37888篇
儿科学   86754篇
妇产科学   76258篇
基础医学   382627篇
口腔科学   80169篇
临床医学   238537篇
内科学   523450篇
皮肤病学   61327篇
神经病学   211888篇
特种医学   103751篇
外国民族医学   659篇
外科学   411536篇
综合类   62996篇
现状与发展   10篇
一般理论   927篇
预防医学   197088篇
眼科学   65398篇
药学   200407篇
  11篇
中国医学   6584篇
肿瘤学   152330篇
  2018年   28327篇
  2017年   21839篇
  2016年   24280篇
  2015年   27655篇
  2014年   38473篇
  2013年   57254篇
  2012年   77656篇
  2011年   82001篇
  2010年   48684篇
  2009年   45945篇
  2008年   76704篇
  2007年   82637篇
  2006年   83200篇
  2005年   79967篇
  2004年   77471篇
  2003年   74172篇
  2002年   72120篇
  2001年   131612篇
  2000年   134778篇
  1999年   112749篇
  1998年   30536篇
  1997年   27256篇
  1996年   26719篇
  1995年   25519篇
  1994年   23533篇
  1993年   21919篇
  1992年   86506篇
  1991年   84070篇
  1990年   81538篇
  1989年   78897篇
  1988年   72522篇
  1987年   71294篇
  1986年   67688篇
  1985年   64325篇
  1984年   47942篇
  1983年   40870篇
  1982年   23834篇
  1981年   21515篇
  1979年   44459篇
  1978年   31284篇
  1977年   26864篇
  1976年   24640篇
  1975年   27186篇
  1974年   32566篇
  1973年   31603篇
  1972年   29817篇
  1971年   27795篇
  1970年   26092篇
  1969年   24729篇
  1968年   23241篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
105.
106.
Porocarcinoma is an unusual, locally aggressive and potentially fatal neoplasm. Several cutaneous malignancies have been described in association with porocarcinoma, including squamous cell carcinoma, basal cell carcinoma and tricholemmal carcinoma. Previous reports have indicated that the occurrence of malignant tumours in combination with porocarcinoma is extremely rare, in particular with regard to Bowen disease (BD). We report an uncommon case of porocarcinoma occurring synchronously in a single BD lesion in a 63‐year‐old woman with multiple BD lesions. The clinical and histological findings confirmed this diagnosis.  相似文献   
107.
Children who expect they can bring about good outcomes and avoid bad outcomes tend to experience more personal successes. Little is known about factors that contribute to these ‘control expectancies’. The purpose of the present study was to determine whether children's internal control expectancies occur in the context of parents’ internal control expectancies, low family strain, and high family cohesiveness and whether these factors are more strongly related to daughters’ than sons’ control expectancies. A community sample of 85 children aged 9–11 years and their parents (85 mothers; 63 fathers) completed rating scales. Fathers’ more internal control expectancies and mothers’ reports of fewer family strains were associated with daughters’ but not sons’ greater internal control expectancies, and greater family cohesiveness was related to both daughters’ and sons’ internal control orientations. These findings suggest that family factors may contribute to children's, particularly daughters’, development of internal control expectancies.  相似文献   
108.
Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis.  相似文献   
109.
110.
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