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   3466209篇
  免费   242982篇
  国内免费   9281篇
耳鼻咽喉   46744篇
儿科学   115644篇
妇产科学   95436篇
基础医学   488750篇
口腔科学   96557篇
临床医学   314773篇
内科学   678303篇
皮肤病学   82191篇
神经病学   282240篇
特种医学   133728篇
外国民族医学   1133篇
外科学   514322篇
综合类   68878篇
现状与发展   5篇
一般理论   1306篇
预防医学   272142篇
眼科学   77954篇
药学   252201篇
  13篇
中国医学   7124篇
肿瘤学   189028篇
  2021年   26914篇
  2019年   28029篇
  2018年   43329篇
  2017年   33589篇
  2016年   37007篇
  2015年   42293篇
  2014年   55330篇
  2013年   82111篇
  2012年   115317篇
  2011年   117994篇
  2010年   69209篇
  2009年   65922篇
  2008年   107611篇
  2007年   114613篇
  2006年   115786篇
  2005年   117589篇
  2004年   114822篇
  2003年   107350篇
  2002年   99749篇
  2001年   156509篇
  2000年   159550篇
  1999年   136122篇
  1998年   38699篇
  1997年   34407篇
  1996年   34434篇
  1995年   33385篇
  1994年   30751篇
  1993年   28627篇
  1992年   107564篇
  1991年   104270篇
  1990年   101547篇
  1989年   98071篇
  1988年   89853篇
  1987年   88557篇
  1986年   83026篇
  1985年   79298篇
  1984年   59055篇
  1983年   50041篇
  1982年   29402篇
  1979年   53158篇
  1978年   37549篇
  1977年   31813篇
  1976年   29495篇
  1975年   31845篇
  1974年   38170篇
  1973年   36299篇
  1972年   33894篇
  1971年   31703篇
  1970年   29278篇
  1969年   27998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.
3.
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   
4.

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   
5.
6.
7.
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   
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