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   1696092篇
  免费   111635篇
  国内免费   2095篇
耳鼻咽喉   21327篇
儿科学   56650篇
妇产科学   46770篇
基础医学   245168篇
口腔科学   42804篇
临床医学   150665篇
内科学   326338篇
皮肤病学   33473篇
神经病学   136469篇
特种医学   65918篇
外国民族医学   302篇
外科学   250533篇
综合类   34893篇
现状与发展   4篇
一般理论   717篇
预防医学   139585篇
眼科学   36925篇
药学   119847篇
  34篇
中国医学   3331篇
肿瘤学   98069篇
  2019年   12295篇
  2018年   38581篇
  2017年   30188篇
  2016年   34740篇
  2015年   17471篇
  2014年   23336篇
  2013年   35218篇
  2012年   52578篇
  2011年   68867篇
  2010年   46871篇
  2009年   38923篇
  2008年   65410篇
  2007年   71773篇
  2006年   48588篇
  2005年   49393篇
  2004年   49182篇
  2003年   48844篇
  2002年   45151篇
  2001年   66735篇
  2000年   68374篇
  1999年   57317篇
  1998年   16293篇
  1997年   14906篇
  1996年   14946篇
  1995年   14160篇
  1994年   13238篇
  1993年   12371篇
  1992年   44944篇
  1991年   44571篇
  1990年   43229篇
  1989年   41902篇
  1988年   38703篇
  1987年   37795篇
  1986年   36064篇
  1985年   34164篇
  1984年   25901篇
  1983年   22590篇
  1982年   13485篇
  1979年   24638篇
  1978年   18036篇
  1977年   15058篇
  1976年   13983篇
  1975年   15137篇
  1974年   18416篇
  1973年   18177篇
  1972年   17116篇
  1971年   16031篇
  1970年   15212篇
  1969年   14235篇
  1968年   13411篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
The value of adding simeprevir (SMV) vs placebo (PBO) to peginterferon and ribavirin (PR) for treatment of chronic hepatitis C virus infection was examined using patient‐reported outcomes (PROs); further, concordance of PROs with virology endpoints and adverse events (AEs) was explored. Patients (= 768 SMV/PR,= 393 PBO/PR) rated fatigue (FSS), depressive symptoms (CES‐D) and functional impairment (WPAI: Hepatitis C Productivity, Daily Activity and Absenteeism) at baseline and throughout treatment in three randomised, double‐blind trials comparing the addition of SMV or PBO during initial 12 weeks of PR. PR was administered for 48 weeks (PBO group) and 24/48 weeks (SMV group) using a response‐guided therapy (RGT) approach. Mean PRO scores (except Absenteeism) worsened from baseline to Week 4 to the same extent in both groups but reverted after Week 24 for SMV/PR and only after Week 48 for PBO/PR. Accordingly, there was a significantly lower area under the curve (baseline–Week 60, AUC60) and fewer weeks with clinically important worsening of scores in the SMV/PR group at any time point. Incidences of patients with fatigue and anaemia AEs were similar in both groups, but FSS scores showed that clinically important increases in fatigue lasted a mean of 6.9 weeks longer with PBO/PR (P < 0.001). PRO score subgroup analysis indicated better outcomes for patients who met the criteria for RGT or achieved sustained virological response 12 weeks post‐treatment (SVR12); differences in mean PRO scores associated with fibrosis level were only observed with PBO/PR. Greater efficacy of SMV/PR enabled reduced treatment duration and reduced time with PR‐related AEs without adding to AE severity.  相似文献   
82.
83.
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   
84.
85.
86.
87.
88.
89.
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   
90.
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   
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