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   2768702篇
  免费   196221篇
  国内免费   8007篇
耳鼻咽喉   36724篇
儿科学   91998篇
妇产科学   76858篇
基础医学   388265篇
口腔科学   75277篇
临床医学   251444篇
内科学   547528篇
皮肤病学   66229篇
神经病学   225836篇
特种医学   109528篇
外国民族医学   821篇
外科学   414070篇
综合类   52383篇
现状与发展   5篇
一般理论   1010篇
预防医学   212973篇
眼科学   60852篇
药学   201333篇
  10篇
中国医学   5488篇
肿瘤学   154298篇
  2019年   21334篇
  2018年   33147篇
  2017年   26698篇
  2016年   29574篇
  2015年   34316篇
  2014年   44901篇
  2013年   64747篇
  2012年   90349篇
  2011年   90587篇
  2010年   54163篇
  2009年   53402篇
  2008年   82991篇
  2007年   88377篇
  2006年   90305篇
  2005年   93830篇
  2004年   92987篇
  2003年   86027篇
  2002年   78125篇
  2001年   131486篇
  2000年   132991篇
  1999年   114329篇
  1998年   32217篇
  1997年   28567篇
  1996年   28886篇
  1995年   28093篇
  1994年   25661篇
  1993年   23975篇
  1992年   89703篇
  1991年   86453篇
  1990年   83830篇
  1989年   80982篇
  1988年   74112篇
  1987年   72631篇
  1986年   68078篇
  1985年   64495篇
  1984年   47817篇
  1983年   40421篇
  1982年   23529篇
  1981年   20844篇
  1979年   42021篇
  1978年   29449篇
  1977年   24837篇
  1976年   22865篇
  1975年   24829篇
  1974年   29371篇
  1973年   27677篇
  1972年   26095篇
  1971年   24279篇
  1970年   22316篇
  1969年   21545篇
排序方式: 共有10000条查询结果,搜索用时 281 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.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases.  相似文献   
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