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   3012973篇
  免费   218543篇
  国内免费   8304篇
耳鼻咽喉   40601篇
儿科学   99773篇
妇产科学   82776篇
基础医学   431083篇
口腔科学   82875篇
临床医学   274895篇
内科学   591912篇
皮肤病学   72208篇
神经病学   243295篇
特种医学   115152篇
外国民族医学   801篇
外科学   449251篇
综合类   60891篇
现状与发展   6篇
一般理论   1092篇
预防医学   229492篇
眼科学   67811篇
药学   221485篇
  9篇
中国医学   6922篇
肿瘤学   167490篇
  2019年   23871篇
  2018年   33758篇
  2017年   25990篇
  2016年   30042篇
  2015年   33782篇
  2014年   46294篇
  2013年   69498篇
  2012年   92162篇
  2011年   97275篇
  2010年   58573篇
  2009年   56061篇
  2008年   90857篇
  2007年   96623篇
  2006年   98286篇
  2005年   93936篇
  2004年   90647篇
  2003年   87377篇
  2002年   84466篇
  2001年   146991篇
  2000年   150439篇
  1999年   126436篇
  1998年   35951篇
  1997年   31789篇
  1996年   32085篇
  1995年   31021篇
  1994年   28487篇
  1993年   26626篇
  1992年   98076篇
  1991年   94892篇
  1990年   91926篇
  1989年   89192篇
  1988年   81528篇
  1987年   79813篇
  1986年   74828篇
  1985年   71239篇
  1984年   52993篇
  1983年   44886篇
  1982年   26307篇
  1981年   23475篇
  1979年   46721篇
  1978年   32999篇
  1977年   28057篇
  1976年   26113篇
  1975年   27907篇
  1974年   32914篇
  1973年   31254篇
  1972年   29314篇
  1971年   27182篇
  1970年   25357篇
  1969年   24109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.
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