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   2501881篇
  免费   199043篇
  国内免费   4544篇
耳鼻咽喉   36661篇
儿科学   77878篇
妇产科学   66435篇
基础医学   353075篇
口腔科学   71556篇
临床医学   225014篇
内科学   490666篇
皮肤病学   51636篇
神经病学   212270篇
特种医学   102104篇
外国民族医学   900篇
外科学   381205篇
综合类   57117篇
现状与发展   1篇
一般理论   1001篇
预防医学   196505篇
眼科学   59039篇
药学   186325篇
  4篇
中国医学   4653篇
肿瘤学   131423篇
  2018年   26365篇
  2017年   20510篇
  2016年   22994篇
  2015年   26001篇
  2014年   36440篇
  2013年   54885篇
  2012年   74783篇
  2011年   78005篇
  2010年   45944篇
  2009年   43693篇
  2008年   74335篇
  2007年   79266篇
  2006年   80191篇
  2005年   78682篇
  2004年   75630篇
  2003年   73245篇
  2002年   72272篇
  2001年   116571篇
  2000年   120664篇
  1999年   102034篇
  1998年   29106篇
  1997年   26544篇
  1996年   26257篇
  1995年   25239篇
  1994年   23752篇
  1993年   22075篇
  1992年   81007篇
  1991年   77944篇
  1990年   75124篇
  1989年   72298篇
  1988年   67149篇
  1987年   66067篇
  1986年   62530篇
  1985年   59573篇
  1984年   45094篇
  1983年   38378篇
  1982年   23374篇
  1981年   20802篇
  1979年   42318篇
  1978年   29731篇
  1977年   24974篇
  1976年   23395篇
  1975年   24742篇
  1974年   30465篇
  1973年   28803篇
  1972年   27000篇
  1971年   24883篇
  1970年   23426篇
  1969年   21700篇
  1968年   19786篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
31.
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   
32.
33.
34.
35.
36.
37.
38.
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   
39.
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   
40.
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