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   2375090篇
  免费   194616篇
  国内免费   4205篇
耳鼻咽喉   34264篇
儿科学   72747篇
妇产科学   62934篇
基础医学   334872篇
口腔科学   67519篇
临床医学   215521篇
内科学   468577篇
皮肤病学   47930篇
神经病学   200770篇
特种医学   95961篇
外国民族医学   886篇
外科学   360385篇
综合类   56216篇
现状与发展   1篇
一般理论   977篇
预防医学   190612篇
眼科学   55463篇
药学   177529篇
  4篇
中国医学   4365篇
肿瘤学   126378篇
  2018年   24209篇
  2016年   20577篇
  2015年   23278篇
  2014年   33536篇
  2013年   50831篇
  2012年   68733篇
  2011年   72276篇
  2010年   42470篇
  2009年   40864篇
  2008年   68759篇
  2007年   73096篇
  2006年   73998篇
  2005年   72035篇
  2004年   69334篇
  2003年   67010篇
  2002年   66260篇
  2001年   112452篇
  2000年   116525篇
  1999年   98335篇
  1998年   27859篇
  1997年   25523篇
  1996年   25449篇
  1995年   24610篇
  1994年   23159篇
  1993年   21553篇
  1992年   79387篇
  1991年   76393篇
  1990年   73577篇
  1989年   70842篇
  1988年   65847篇
  1987年   64800篇
  1986年   61334篇
  1985年   58400篇
  1984年   44223篇
  1983年   37657篇
  1982年   22886篇
  1981年   20332篇
  1980年   19034篇
  1979年   41301篇
  1978年   28985篇
  1977年   24346篇
  1976年   22832篇
  1975年   23964篇
  1974年   29640篇
  1973年   28043篇
  1972年   26227篇
  1971年   24154篇
  1970年   22753篇
  1969年   21087篇
  1968年   19135篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
52.
53.
54.
55.
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   
56.
57.
58.
59.
60.
To evaluate the changes in alveolar contour after guided bone regeneration (GBR) with two different combinations of biomaterials in dehiscence defects arou  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