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   2760531篇
  免费   190911篇
  国内免费   7571篇
耳鼻咽喉   35624篇
儿科学   91802篇
妇产科学   74844篇
基础医学   382313篇
口腔科学   71377篇
临床医学   246687篇
内科学   546541篇
皮肤病学   63285篇
神经病学   229410篇
特种医学   108947篇
外国民族医学   741篇
外科学   416681篇
综合类   52994篇
现状与发展   5篇
一般理论   981篇
预防医学   213035篇
眼科学   59744篇
药学   197488篇
  8篇
中国医学   5963篇
肿瘤学   160543篇
  2021年   20222篇
  2019年   20809篇
  2018年   49639篇
  2017年   38727篇
  2016年   45072篇
  2015年   30678篇
  2014年   41469篇
  2013年   61585篇
  2012年   87238篇
  2011年   104554篇
  2010年   68462篇
  2009年   60263篇
  2008年   98264篇
  2007年   105885篇
  2006年   86800篇
  2005年   84874篇
  2004年   83275篇
  2003年   81801篇
  2002年   77050篇
  2001年   128928篇
  2000年   132057篇
  1999年   110885篇
  1998年   31634篇
  1997年   28334篇
  1996年   28447篇
  1995年   27614篇
  1994年   25327篇
  1993年   23622篇
  1992年   85370篇
  1991年   81813篇
  1990年   79052篇
  1989年   76263篇
  1988年   69664篇
  1987年   68186篇
  1986年   63700篇
  1985年   60696篇
  1984年   45103篇
  1983年   38102篇
  1982年   22629篇
  1981年   20091篇
  1979年   39111篇
  1978年   27563篇
  1977年   23312篇
  1976年   21601篇
  1975年   22875篇
  1974年   26880篇
  1973年   25439篇
  1972年   23816篇
  1971年   21991篇
  1970年   20222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