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   2298109篇
  免费   171714篇
  国内免费   3356篇
耳鼻咽喉   32136篇
儿科学   77732篇
妇产科学   63513篇
基础医学   334026篇
口腔科学   63211篇
临床医学   208697篇
内科学   450672篇
皮肤病学   49759篇
神经病学   182462篇
特种医学   88399篇
外国民族医学   898篇
外科学   338157篇
综合类   49153篇
现状与发展   4篇
一般理论   892篇
预防医学   183844篇
眼科学   51866篇
药学   169862篇
  8篇
中国医学   4104篇
肿瘤学   123784篇
  2018年   24028篇
  2017年   18201篇
  2016年   19962篇
  2015年   22871篇
  2014年   31629篇
  2013年   48556篇
  2012年   66483篇
  2011年   70882篇
  2010年   41631篇
  2009年   39925篇
  2008年   67234篇
  2007年   72056篇
  2006年   71940篇
  2005年   70321篇
  2004年   68221篇
  2003年   65638篇
  2002年   64136篇
  2001年   105048篇
  2000年   108228篇
  1999年   91911篇
  1998年   25820篇
  1997年   23303篇
  1996年   23923篇
  1995年   22616篇
  1994年   21290篇
  1993年   19824篇
  1992年   73347篇
  1991年   71954篇
  1990年   69887篇
  1989年   67293篇
  1988年   62204篇
  1987年   61237篇
  1986年   57697篇
  1985年   55088篇
  1984年   41743篇
  1983年   35650篇
  1982年   21019篇
  1981年   19198篇
  1979年   38390篇
  1978年   27616篇
  1977年   23189篇
  1976年   21700篇
  1975年   23339篇
  1974年   27831篇
  1973年   27235篇
  1972年   25431篇
  1971年   23464篇
  1970年   22059篇
  1969年   20548篇
  1968年   18977篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
41.
European Journal of Orthopaedic Surgery & Traumatology - The goals of this study were to compare patient satisfaction and wound-related complications in patients receiving 2-octyl cyanoacrylate...  相似文献   
42.
43.
Advancement in microelectromechanical system has facilitated the microfabrication of polymeric substrates and the development of the novel class of controlled drug delivery devices. These vehicles have specifically tailored three dimensional physical and chemical features which together, provide the capacity to target cell, stimulate unidirectional controlled release of therapeutics and augment permeation across the barriers. Apart from drug delivery devices microfabrication technology’s offer exciting prospects to generate biomimetic gastrointestinal tract models. BioMEMS are capable of analysing biochemical liquid sample like solution of metabolites, macromolecules, proteins, nucleic acid, cells and viruses. This review summarized multidisciplinary application of biomedical microelectromechanical systems in drug delivery and its potential in analytical procedures.  相似文献   
44.
45.
46.
In the 6th Basic Plan for Long-Term Electricity Supply and Demand (6th BPE) for Korea, for the first time, the environmental costs of air pollution caused by oxides of sulfur (SOx), oxides of nitrogen (NOx), and particulate matters (PM) from power plants were estimated and included. However, several deficiencies in evaluating the environmental costs were found. In this study, (1) the validity of the environmental costs used in the 6th BPE was assessed, (2) a systematic approach was suggested and used to improve the environmental costs estimation, and (3) the sensitivity of the cost of generating electricity to the environmental costs by fuel type with the proposed approach was discussed. We found that the applied environmental costs used in the 6th BPE did not fully include the demographic characteristics of Korea. By applying more realistic parameter values, it was found that the newly estimated environmental cost was about 23 times higher than the cost estimated in the original 6th BPE for coal-fired power plants and about 1.5 times higher for liquefied natural gas (LNG)-fired power plants, suggesting that LNG-fired power plants are more economical if using more realistic environmental costs. Thus, it is critical to check the validity of parameter values when calculating environmental costs.  相似文献   
47.
48.
DNA methylation at CpG dinucleotides is an important epigenetic regulator common to virtually all mammalian cell types, but recent evidence indicates that during early postnatal development neuronal genomes also accumulate uniquely high levels of two alternative forms of methylation, non-CpG methylation and hydroxymethylation. Here we discuss the distinct landscape of DNA methylation in neurons, how it is established, and how it might affect the binding and function of protein readers of DNA methylation. We review studies of one critical reader of DNA methylation in the brain, the Rett syndrome protein methyl CpG-binding protein 2 (MeCP2), and discuss how differential binding affinity of MeCP2 for non-CpG and hydroxymethylation may affect the function of this methyl-binding protein in the nervous system.  相似文献   
49.
50.
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