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   10335篇
  免费   712篇
  国内免费   52篇
耳鼻咽喉   53篇
儿科学   358篇
妇产科学   337篇
基础医学   1544篇
口腔科学   149篇
临床医学   991篇
内科学   2434篇
皮肤病学   255篇
神经病学   954篇
特种医学   157篇
外科学   910篇
综合类   90篇
一般理论   8篇
预防医学   1118篇
眼科学   280篇
药学   760篇
中国医学   53篇
肿瘤学   648篇
  2023年   74篇
  2022年   194篇
  2021年   369篇
  2020年   224篇
  2019年   310篇
  2018年   339篇
  2017年   242篇
  2016年   260篇
  2015年   335篇
  2014年   441篇
  2013年   556篇
  2012年   845篇
  2011年   899篇
  2010年   495篇
  2009年   427篇
  2008年   739篇
  2007年   744篇
  2006年   666篇
  2005年   596篇
  2004年   491篇
  2003年   453篇
  2002年   436篇
  2001年   77篇
  2000年   49篇
  1999年   66篇
  1998年   73篇
  1997年   48篇
  1996年   42篇
  1995年   47篇
  1994年   23篇
  1993年   35篇
  1992年   42篇
  1991年   44篇
  1990年   31篇
  1989年   30篇
  1988年   23篇
  1987年   22篇
  1986年   18篇
  1985年   22篇
  1984年   22篇
  1983年   17篇
  1982年   18篇
  1981年   28篇
  1979年   12篇
  1978年   17篇
  1977年   24篇
  1976年   18篇
  1974年   13篇
  1973年   13篇
  1970年   10篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
Case report A 28-year-old female patient was admitted because of painlessmacroscopic haematuria. Past history included severe mentalretardation and nystagmus. At age 17, a computed tomography(CT) scan of the brain showed an absent cerebellar vermis andcerebellar hypoplasia. There was no  相似文献   
4.
5.
As the biological width is established around neighboring implants, there is a flattening of the interimplant bone and a change in the position of the soft tissue. As a result, a normal progression of papilla from natural teeth through the adjacent implant area is lost. This presentation describes various techniques and strategies to improve the aesthetic outcome of anterior implant restorations, together with the use of a scalloped implant designed to sustain the interdental bony peaks, and in doing so, maintain the interimplant papillae.  相似文献   
6.

Objective  

The aim of the project was to assess the effectiveness and safety of weekly epoetin-beta (EB) in patients with gastrointestinal cancer (GIC) subjected to concomitant chemoradiotherapy (CCTRT).  相似文献   
7.
8.
Exposure to trauma and stress has been linked with poor health, while forgiveness appears to be positively associated with health outcomes. The current study investigates whether traits such as forgiveness and ruminative tendencies predict levels of trauma and stress experienced by New York City residents on the 1‐year anniversary of the September 11th terrorist attack. Seventy‐one students and staff members (57 females, 14 males) of a graduate school in New York City were administered the Impact of Events Scale, the Perceived Stress Scale, and questionnaires designed for the purpose of this study to measure ruminative tendencies and forgiveness on September 11, 2002. Rumination predicted levels of trauma (p < 0.05) and perceived stress (p < 0.01). Lower levels of forgiveness predicted perceived stress (p < 0.05), but not trauma. Rumination mediated the relationship between forgiveness and perceived stress. These findings suggest that individuals with higher levels of rumination have an elevated risk of experiencing trauma and stress‐related symptoms following a traumatic event. Forgiveness is associated with lower levels of stress, but not trauma, perhaps because trauma is an extreme form of stress. Forgiveness appears to serve as a buffer against stress more so in individuals with low levels of rumination than in individuals with high levels of rumination. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
9.
Abstract Caries experience and enamel fluorosis prevalence in 8-year-old children belonging to different socio-economic classes were determined in two Chilean twin cities that are served by optimally fluoridated community water from the same waterworks facility. Low socio-economic status (LSES) children had a higher mean dm ft and DMFT indices (P<0.001) than high socioeconomic status (HSES) children. Prevalence of enamel fluorosis in the permanent teeth of LSES children was 0.79, significantly higher (X2= 9.0; P<0.003) than the value 0.59 found in HSES children. The proportion of Dean's scores 2. 3, 4 and 5 in first molars, mandibular and maxillary incisors in LSES children was higher than in HSES children (P<0.001). Differences in prevalence and seventy of enamel fluorosis between both groups are tentatively attributed lo a different pattern of tap water and tea consumption at pre-school ages. Suggestions are advanced to minimize the undesirable prevalence and severity of enamel fluorosis.  相似文献   
10.
A novel chiral redox-active ferrocene compound (FcVI) with amphiphilic properties has been synthesized. Cryogenic Transmission Electron Microscopy (cryo-TEM) has been used to estimate the shape and size of the FcVI aggregates in solution. Uni- and multi-lamellar vesicles (between 40 and 300 nm in diameter) were observed in water. Large particles (of more than 1 μm in diameter) with a hexagonal fine structure were found in 50 mM aqueous Na2SO4 solution. Sonication transformed the latter into ‘rosette’-like structures. Cyclic voltammetry has been employed to investigate the electrochemical properties of FcVI. The amphiphile adsorbed on graphite electrodes and a reversible electrochemical behaviour, characteristic of ferrocene, was observed with redox potentials between 330 and 350 mV.  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