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   4212877篇
  免费   300644篇
  国内免费   9935篇
耳鼻咽喉   56819篇
儿科学   140035篇
妇产科学   116836篇
基础医学   591070篇
口腔科学   116675篇
临床医学   388125篇
内科学   811779篇
皮肤病学   95165篇
神经病学   346299篇
特种医学   161598篇
外国民族医学   1316篇
外科学   625781篇
综合类   91955篇
现状与发展   7篇
一般理论   1756篇
预防医学   339533篇
眼科学   96398篇
药学   304257篇
  12篇
中国医学   8808篇
肿瘤学   229232篇
  2018年   62397篇
  2017年   48325篇
  2016年   55566篇
  2015年   44916篇
  2014年   62210篇
  2013年   94035篇
  2012年   130291篇
  2011年   150118篇
  2010年   94348篇
  2009年   85298篇
  2008年   140062篇
  2007年   150371篇
  2006年   133610篇
  2005年   130994篇
  2004年   127186篇
  2003年   123622篇
  2002年   117986篇
  2001年   186383篇
  2000年   191171篇
  1999年   161042篇
  1998年   47802篇
  1997年   42601篇
  1996年   42520篇
  1995年   40920篇
  1994年   37627篇
  1993年   35272篇
  1992年   126238篇
  1991年   122584篇
  1990年   119013篇
  1989年   114879篇
  1988年   105945篇
  1987年   103880篇
  1986年   97952篇
  1985年   93763篇
  1984年   70849篇
  1983年   60597篇
  1982年   36368篇
  1981年   32699篇
  1979年   64287篇
  1978年   46072篇
  1977年   38945篇
  1976年   36304篇
  1975年   38558篇
  1974年   46305篇
  1973年   44727篇
  1972年   42214篇
  1971年   39204篇
  1970年   36622篇
  1969年   34775篇
  1968年   32333篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  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.
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   
7.
8.
9.
10.
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