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   3369412篇
  免费   245900篇
  国内免费   8406篇
耳鼻咽喉   45404篇
儿科学   111000篇
妇产科学   94249篇
基础医学   479830篇
口腔科学   93979篇
临床医学   311064篇
内科学   658588篇
皮肤病学   78989篇
神经病学   276316篇
特种医学   128872篇
外国民族医学   964篇
外科学   496489篇
综合类   69107篇
现状与发展   7篇
一般理论   1452篇
预防医学   266268篇
眼科学   75936篇
药学   246285篇
  12篇
中国医学   6466篇
肿瘤学   182441篇
  2019年   26501篇
  2018年   36844篇
  2017年   28378篇
  2016年   32490篇
  2015年   36894篇
  2014年   50850篇
  2013年   77083篇
  2012年   102576篇
  2011年   108823篇
  2010年   65142篇
  2009年   62601篇
  2008年   102194篇
  2007年   108681篇
  2006年   109880篇
  2005年   105993篇
  2004年   102002篇
  2003年   98306篇
  2002年   95004篇
  2001年   156409篇
  2000年   160061篇
  1999年   135208篇
  1998年   39221篇
  1997年   35009篇
  1996年   35478篇
  1995年   34127篇
  1994年   31452篇
  1993年   29504篇
  1992年   106339篇
  1991年   103206篇
  1990年   99997篇
  1989年   96531篇
  1988年   89017篇
  1987年   87238篇
  1986年   82264篇
  1985年   78397篇
  1984年   58984篇
  1983年   50319篇
  1982年   30025篇
  1981年   26986篇
  1979年   53102篇
  1978年   38028篇
  1977年   32263篇
  1976年   29842篇
  1975年   31948篇
  1974年   38069篇
  1973年   36720篇
  1972年   34566篇
  1971年   32116篇
  1970年   29895篇
  1969年   28542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.

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