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   3374843篇
  免费   246566篇
  国内免费   8420篇
耳鼻咽喉   45504篇
儿科学   111259篇
妇产科学   94413篇
基础医学   480562篇
口腔科学   94197篇
临床医学   311927篇
内科学   659304篇
皮肤病学   79121篇
神经病学   276768篇
特种医学   129079篇
外国民族医学   964篇
外科学   497167篇
综合类   69334篇
现状与发展   7篇
一般理论   1454篇
预防医学   266834篇
眼科学   76026篇
药学   246747篇
  12篇
中国医学   6481篇
肿瘤学   182669篇
  2019年   26618篇
  2018年   36963篇
  2017年   28490篇
  2016年   32591篇
  2015年   36991篇
  2014年   50952篇
  2013年   77292篇
  2012年   102749篇
  2011年   109018篇
  2010年   65272篇
  2009年   62732篇
  2008年   102416篇
  2007年   108926篇
  2006年   110125篇
  2005年   106187篇
  2004年   102197篇
  2003年   98489篇
  2002年   95225篇
  2001年   156559篇
  2000年   160238篇
  1999年   135341篇
  1998年   39301篇
  1997年   35071篇
  1996年   35549篇
  1995年   34196篇
  1994年   31529篇
  1993年   29598篇
  1992年   106439篇
  1991年   103313篇
  1990年   100105篇
  1989年   96622篇
  1988年   89094篇
  1987年   87321篇
  1986年   82333篇
  1985年   78488篇
  1984年   59033篇
  1983年   50349篇
  1982年   30050篇
  1981年   27030篇
  1979年   53140篇
  1978年   38049篇
  1977年   32311篇
  1976年   29899篇
  1975年   32004篇
  1974年   38102篇
  1973年   36774篇
  1972年   34626篇
  1971年   32182篇
  1970年   29948篇
  1969年   28573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.
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