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   4631183篇
  免费   342784篇
  国内免费   11099篇
耳鼻咽喉   66854篇
儿科学   150439篇
妇产科学   128377篇
基础医学   650252篇
口腔科学   135555篇
临床医学   425757篇
内科学   886728篇
皮肤病学   104019篇
神经病学   380166篇
特种医学   179835篇
外国民族医学   1687篇
外科学   696698篇
综合类   104995篇
现状与发展   7篇
一般理论   1903篇
预防医学   370986篇
眼科学   109606篇
药学   344509篇
  12篇
中国医学   9015篇
肿瘤学   237666篇
  2018年   48718篇
  2017年   37255篇
  2016年   42405篇
  2015年   47872篇
  2014年   67461篇
  2013年   103099篇
  2012年   137196篇
  2011年   146059篇
  2010年   87521篇
  2009年   83222篇
  2008年   137227篇
  2007年   146432篇
  2006年   148278篇
  2005年   143745篇
  2004年   138569篇
  2003年   133604篇
  2002年   130289篇
  2001年   205867篇
  2000年   211827篇
  1999年   179987篇
  1998年   54516篇
  1997年   48232篇
  1996年   47786篇
  1995年   46170篇
  1994年   42925篇
  1993年   40289篇
  1992年   144128篇
  1991年   140311篇
  1990年   136348篇
  1989年   132119篇
  1988年   122285篇
  1987年   120556篇
  1986年   114388篇
  1985年   109842篇
  1984年   82641篇
  1983年   71050篇
  1982年   42940篇
  1981年   38483篇
  1979年   77278篇
  1978年   54845篇
  1977年   46737篇
  1976年   43987篇
  1975年   47055篇
  1974年   56839篇
  1973年   54423篇
  1972年   51588篇
  1971年   47863篇
  1970年   44981篇
  1969年   42639篇
  1968年   39563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.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
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