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   4199282篇
  免费   314272篇
  国内免费   10712篇
耳鼻咽喉   59672篇
儿科学   135129篇
妇产科学   114470篇
基础医学   587199篇
口腔科学   121337篇
临床医学   386522篇
内科学   812975篇
皮肤病学   94586篇
神经病学   350380篇
特种医学   164639篇
外国民族医学   1447篇
外科学   631818篇
综合类   92322篇
现状与发展   6篇
一般理论   1899篇
预防医学   332796篇
眼科学   98254篇
药学   310308篇
  11篇
中国医学   8299篇
肿瘤学   220197篇
  2019年   33453篇
  2018年   47076篇
  2017年   36101篇
  2016年   41182篇
  2015年   46437篇
  2014年   64782篇
  2013年   97669篇
  2012年   130620篇
  2011年   138092篇
  2010年   82663篇
  2009年   78567篇
  2008年   129166篇
  2007年   137129篇
  2006年   138781篇
  2005年   134690篇
  2004年   129494篇
  2003年   124804篇
  2002年   121226篇
  2001年   189304篇
  2000年   194670篇
  1999年   165432篇
  1998年   49746篇
  1997年   44239篇
  1996年   43706篇
  1995年   42335篇
  1994年   39237篇
  1993年   36705篇
  1992年   130716篇
  1991年   126473篇
  1990年   122292篇
  1989年   118176篇
  1988年   109209篇
  1987年   107507篇
  1986年   101613篇
  1985年   97341篇
  1984年   73297篇
  1983年   62602篇
  1982年   37811篇
  1981年   34084篇
  1979年   67441篇
  1978年   47810篇
  1977年   40493篇
  1976年   37922篇
  1975年   40176篇
  1974年   48586篇
  1973年   46354篇
  1972年   43662篇
  1971年   40450篇
  1970年   37785篇
  1969年   35721篇
排序方式: 共有10000条查询结果,搜索用时 31 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.
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