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   1562977篇
  免费   110025篇
  国内免费   3380篇
耳鼻咽喉   21540篇
儿科学   53455篇
妇产科学   43423篇
基础医学   235282篇
口腔科学   44354篇
临床医学   137930篇
内科学   294506篇
皮肤病学   37109篇
神经病学   122172篇
特种医学   61238篇
外国民族医学   386篇
外科学   236063篇
综合类   31832篇
一般理论   514篇
预防医学   117847篇
眼科学   37075篇
药学   115682篇
  3篇
中国医学   3196篇
肿瘤学   82775篇
  2018年   17000篇
  2017年   13051篇
  2016年   15324篇
  2015年   17257篇
  2014年   22538篇
  2013年   34326篇
  2012年   46497篇
  2011年   49105篇
  2010年   29131篇
  2009年   26948篇
  2008年   46471篇
  2007年   49727篇
  2006年   50500篇
  2005年   49024篇
  2004年   47579篇
  2003年   45888篇
  2002年   44552篇
  2001年   70540篇
  2000年   72545篇
  1999年   60556篇
  1998年   16900篇
  1997年   15000篇
  1996年   15067篇
  1995年   14232篇
  1994年   13237篇
  1993年   12417篇
  1992年   46892篇
  1991年   46681篇
  1990年   46267篇
  1989年   44624篇
  1988年   40851篇
  1987年   40828篇
  1986年   38140篇
  1985年   36859篇
  1984年   27546篇
  1983年   23250篇
  1982年   13706篇
  1981年   12484篇
  1979年   26011篇
  1978年   18883篇
  1977年   15985篇
  1976年   15166篇
  1975年   16600篇
  1974年   19893篇
  1973年   18885篇
  1972年   17833篇
  1971年   16809篇
  1970年   15572篇
  1969年   14654篇
  1968年   13685篇
排序方式: 共有10000条查询结果,搜索用时 15 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.
Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
4.
5.
6.
7.
8.
9.
10.
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   
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