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   4563203篇
  免费   328297篇
  国内免费   10111篇
耳鼻咽喉   65169篇
儿科学   150954篇
妇产科学   127431篇
基础医学   650959篇
口腔科学   130384篇
临床医学   419192篇
内科学   871086篇
皮肤病学   104856篇
神经病学   368528篇
特种医学   173576篇
外国民族医学   1426篇
外科学   685507篇
综合类   98339篇
现状与发展   15篇
一般理论   1794篇
预防医学   359588篇
眼科学   108404篇
药学   338133篇
  16篇
中国医学   8935篇
肿瘤学   237319篇
  2018年   49409篇
  2017年   37410篇
  2016年   42960篇
  2015年   48432篇
  2014年   67741篇
  2013年   103174篇
  2012年   138996篇
  2011年   148005篇
  2010年   88963篇
  2009年   84274篇
  2008年   138754篇
  2007年   147928篇
  2006年   149970篇
  2005年   145152篇
  2004年   139716篇
  2003年   134805篇
  2002年   130739篇
  2001年   201447篇
  2000年   206822篇
  1999年   175244篇
  1998年   53055篇
  1997年   46454篇
  1996年   46535篇
  1995年   44451篇
  1994年   41085篇
  1993年   38634篇
  1992年   139088篇
  1991年   135448篇
  1990年   132122篇
  1989年   128397篇
  1988年   118604篇
  1987年   116559篇
  1986年   110336篇
  1985年   105945篇
  1984年   79375篇
  1983年   68111篇
  1982年   40895篇
  1981年   36758篇
  1979年   73640篇
  1978年   52352篇
  1977年   44649篇
  1976年   42077篇
  1975年   45465篇
  1974年   54080篇
  1973年   51811篇
  1972年   49082篇
  1971年   46008篇
  1970年   42844篇
  1969年   41084篇
  1968年   38091篇
排序方式: 共有10000条查询结果,搜索用时 265 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.
Journal of Medical Ultrasonics - Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced...  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