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   3461634篇
  免费   253664篇
  国内免费   8874篇
耳鼻咽喉   47719篇
儿科学   114952篇
妇产科学   94791篇
基础医学   486318篇
口腔科学   95021篇
临床医学   315472篇
内科学   681782篇
皮肤病学   80745篇
神经病学   283022篇
特种医学   134715篇
外国民族医学   1291篇
外科学   521522篇
综合类   71144篇
现状与发展   6篇
一般理论   1316篇
预防医学   265844篇
眼科学   78232篇
药学   254352篇
  9篇
中国医学   6956篇
肿瘤学   188963篇
  2019年   27971篇
  2018年   38982篇
  2017年   29864篇
  2016年   34278篇
  2015年   38603篇
  2014年   53398篇
  2013年   80240篇
  2012年   107965篇
  2011年   114639篇
  2010年   69025篇
  2009年   66000篇
  2008年   107151篇
  2007年   114045篇
  2006年   115475篇
  2005年   111447篇
  2004年   107448篇
  2003年   103497篇
  2002年   100324篇
  2001年   162374篇
  2000年   166585篇
  1999年   141357篇
  1998年   41515篇
  1997年   36825篇
  1996年   36855篇
  1995年   35499篇
  1994年   32861篇
  1993年   30798篇
  1992年   110747篇
  1991年   106930篇
  1990年   103801篇
  1989年   100237篇
  1988年   91978篇
  1987年   90259篇
  1986年   84470篇
  1985年   80748篇
  1984年   60515篇
  1983年   51289篇
  1982年   30465篇
  1981年   27515篇
  1979年   53709篇
  1978年   37887篇
  1977年   32273篇
  1976年   29971篇
  1975年   31975篇
  1974年   37639篇
  1973年   35836篇
  1972年   33508篇
  1971年   30847篇
  1970年   28758篇
  1969年   27090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