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   998459篇
  免费   77142篇
  国内免费   2613篇
耳鼻咽喉   13022篇
儿科学   34605篇
妇产科学   28594篇
基础医学   145698篇
口腔科学   27725篇
临床医学   90643篇
内科学   193591篇
皮肤病学   22995篇
神经病学   79525篇
特种医学   38455篇
外国民族医学   305篇
外科学   149802篇
综合类   23754篇
一般理论   390篇
预防医学   78148篇
眼科学   22679篇
药学   72119篇
  3篇
中国医学   2032篇
肿瘤学   54129篇
  2018年   10837篇
  2017年   8458篇
  2016年   9621篇
  2015年   10801篇
  2014年   14677篇
  2013年   22309篇
  2012年   29385篇
  2011年   31250篇
  2010年   18689篇
  2009年   17604篇
  2008年   29038篇
  2007年   30673篇
  2006年   31158篇
  2005年   29821篇
  2004年   29072篇
  2003年   27958篇
  2002年   26936篇
  2001年   46940篇
  2000年   48038篇
  1999年   40267篇
  1998年   11193篇
  1997年   10101篇
  1996年   10167篇
  1995年   9777篇
  1994年   9096篇
  1993年   8482篇
  1992年   32249篇
  1991年   31459篇
  1990年   31007篇
  1989年   29874篇
  1988年   27145篇
  1987年   27315篇
  1986年   25403篇
  1985年   24584篇
  1984年   18364篇
  1983年   15461篇
  1982年   9249篇
  1981年   8330篇
  1979年   16822篇
  1978年   12191篇
  1977年   10281篇
  1976年   9718篇
  1975年   10153篇
  1974年   12298篇
  1973年   11827篇
  1972年   10878篇
  1971年   10104篇
  1970年   9370篇
  1969年   8713篇
  1968年   8093篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
1.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
2.

Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017–6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD21lo/neg cells are significantly increased in SSc-ILD but not in SSc without ILD (15.4 ± 13.3% vs. 5.8 ± 0.9%, p = 0.002) or healthy controls (5.0 ± 0.5%, p < 0.0001). While CD21lo/neg B cells can be identified from a single biaxial gate, tSNE analysis reveals that the biaxial gate is comprised of multiple distinct subsets, all of which are increased in SSc-ILD. CD21lo/neg cells in both healthy controls and SSc-ILD are predominantly tBET positive and do not have intracellular CD21. Immunohistochemistry staining demonstrated that CD21lo/neg B cells diffusely infiltrate the lung parenchyma of an SSc-ILD patient. Additional work is needed to validate this biomarker in larger cohorts and longitudinal studies and to understand the role of these cells in SSc-ILD.

  相似文献   
3.
4.
5.
6.
7.
8.
9.
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study...  相似文献   
10.
Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.  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