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   2905611篇
  免费   205391篇
  国内免费   7821篇
耳鼻咽喉   38880篇
儿科学   95805篇
妇产科学   79645篇
基础医学   420234篇
口腔科学   77913篇
临床医学   264808篇
内科学   568731篇
皮肤病学   69744篇
神经病学   233643篇
特种医学   111767篇
外国民族医学   774篇
外科学   434739篇
综合类   55669篇
现状与发展   6篇
一般理论   1042篇
预防医学   220624篇
眼科学   64727篇
药学   213621篇
  9篇
中国医学   5969篇
肿瘤学   160473篇
  2019年   22803篇
  2018年   32504篇
  2017年   24915篇
  2016年   28966篇
  2015年   32537篇
  2014年   44557篇
  2013年   66656篇
  2012年   89424篇
  2011年   95023篇
  2010年   57113篇
  2009年   54337篇
  2008年   88477篇
  2007年   94347篇
  2006年   95800篇
  2005年   91617篇
  2004年   88290篇
  2003年   85420篇
  2002年   82410篇
  2001年   139984篇
  2000年   143246篇
  1999年   120589篇
  1998年   34350篇
  1997年   30425篇
  1996年   30702篇
  1995年   29666篇
  1994年   27039篇
  1993年   25451篇
  1992年   93279篇
  1991年   91013篇
  1990年   88330篇
  1989年   85528篇
  1988年   78313篇
  1987年   76798篇
  1986年   71841篇
  1985年   68680篇
  1984年   50968篇
  1983年   43031篇
  1982年   25057篇
  1981年   22417篇
  1979年   45018篇
  1978年   31738篇
  1977年   26697篇
  1976年   25259篇
  1975年   27398篇
  1974年   32025篇
  1973年   30451篇
  1972年   28487篇
  1971年   26559篇
  1970年   24527篇
  1969年   23509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.
Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses...  相似文献   
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