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   3013234篇
  免费   218674篇
  国内免费   8376篇
耳鼻咽喉   40650篇
儿科学   99829篇
妇产科学   82760篇
基础医学   431453篇
口腔科学   82877篇
临床医学   274837篇
内科学   591537篇
皮肤病学   72266篇
神经病学   243376篇
特种医学   115344篇
外国民族医学   801篇
外科学   449425篇
综合类   60880篇
现状与发展   8篇
一般理论   1090篇
预防医学   229148篇
眼科学   67820篇
药学   221692篇
  9篇
中国医学   6958篇
肿瘤学   167524篇
  2021年   23523篇
  2019年   23972篇
  2018年   33834篇
  2017年   26057篇
  2016年   30139篇
  2015年   33943篇
  2014年   46494篇
  2013年   69702篇
  2012年   92447篇
  2011年   97563篇
  2010年   58721篇
  2009年   56181篇
  2008年   91018篇
  2007年   96768篇
  2006年   98445篇
  2005年   94006篇
  2004年   90743篇
  2003年   87407篇
  2002年   84510篇
  2001年   147003篇
  2000年   150436篇
  1999年   126456篇
  1998年   35963篇
  1997年   31796篇
  1996年   32086篇
  1995年   31024篇
  1994年   28490篇
  1993年   26625篇
  1992年   98065篇
  1991年   94878篇
  1990年   91904篇
  1989年   89182篇
  1988年   81514篇
  1987年   79791篇
  1986年   74815篇
  1985年   71235篇
  1984年   52993篇
  1983年   44893篇
  1982年   26308篇
  1979年   46726篇
  1978年   32991篇
  1977年   28053篇
  1976年   26116篇
  1975年   27913篇
  1974年   32901篇
  1973年   31247篇
  1972年   29311篇
  1971年   27180篇
  1970年   25348篇
  1969年   24098篇
排序方式: 共有10000条查询结果,搜索用时 31 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.
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   
6.
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