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   1431778篇
  免费   104905篇
  国内免费   3107篇
耳鼻咽喉   19085篇
儿科学   48808篇
妇产科学   39951篇
基础医学   216548篇
口腔科学   40436篇
临床医学   128062篇
内科学   271458篇
皮肤病学   33299篇
神经病学   109858篇
特种医学   54098篇
外国民族医学   365篇
外科学   215062篇
综合类   30944篇
一般理论   487篇
预防医学   111665篇
眼科学   33385篇
药学   106423篇
  3篇
中国医学   2906篇
肿瘤学   76947篇
  2018年   14696篇
  2016年   12741篇
  2015年   14312篇
  2014年   19457篇
  2013年   30048篇
  2012年   39769篇
  2011年   42871篇
  2010年   25412篇
  2009年   24001篇
  2008年   40274篇
  2007年   42886篇
  2006年   43647篇
  2005年   41795篇
  2004年   40773篇
  2003年   39113篇
  2002年   37964篇
  2001年   66543篇
  2000年   68478篇
  1999年   57068篇
  1998年   15738篇
  1997年   14061篇
  1996年   14384篇
  1995年   13648篇
  1994年   12698篇
  1993年   11906篇
  1992年   45295篇
  1991年   45089篇
  1990年   44727篇
  1989年   43147篇
  1988年   39534篇
  1987年   39562篇
  1986年   36935篇
  1985年   35685篇
  1984年   26638篇
  1983年   22499篇
  1982年   13161篇
  1981年   11995篇
  1979年   24956篇
  1978年   18121篇
  1977年   15316篇
  1976年   14605篇
  1975年   15754篇
  1974年   19049篇
  1973年   18089篇
  1972年   17022篇
  1971年   16030篇
  1970年   14850篇
  1969年   13980篇
  1968年   13044篇
  1967年   11691篇
排序方式: 共有10000条查询结果,搜索用时 31 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