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   2792356篇
  免费   202498篇
  国内免费   7737篇
耳鼻咽喉   37706篇
儿科学   92663篇
妇产科学   77822篇
基础医学   395354篇
口腔科学   75621篇
临床医学   253984篇
内科学   551421篇
皮肤病学   66845篇
神经病学   228549篇
特种医学   107802篇
外国民族医学   769篇
外科学   418702篇
综合类   56243篇
现状与发展   6篇
一般理论   1125篇
预防医学   212421篇
眼科学   61888篇
药学   203604篇
  8篇
中国医学   5825篇
肿瘤学   154233篇
  2021年   21644篇
  2019年   22382篇
  2018年   31828篇
  2017年   24406篇
  2016年   28361篇
  2015年   31888篇
  2014年   43705篇
  2013年   65805篇
  2012年   86780篇
  2011年   91456篇
  2010年   55508篇
  2009年   53109篇
  2008年   85334篇
  2007年   90755篇
  2006年   92349篇
  2005年   88314篇
  2004年   85104篇
  2003年   82155篇
  2002年   79173篇
  2001年   135988篇
  2000年   139179篇
  1999年   117196篇
  1998年   33390篇
  1997年   29834篇
  1996年   29936篇
  1995年   29059篇
  1994年   26663篇
  1993年   24938篇
  1992年   90449篇
  1991年   87017篇
  1990年   84264篇
  1989年   81462篇
  1988年   74538篇
  1987年   72932篇
  1986年   68226篇
  1985年   65182篇
  1984年   48424篇
  1983年   40975篇
  1982年   24371篇
  1981年   21609篇
  1979年   42439篇
  1978年   29971篇
  1977年   25451篇
  1976年   23472篇
  1975年   25045篇
  1974年   29523篇
  1973年   28116篇
  1972年   26376篇
  1971年   24403篇
  1970年   22543篇
排序方式: 共有10000条查询结果,搜索用时 15 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.
3.

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   
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