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   3346649篇
  免费   234967篇
  国内免费   8671篇
耳鼻咽喉   46108篇
儿科学   110267篇
妇产科学   92539篇
基础医学   471987篇
口腔科学   92957篇
临床医学   301771篇
内科学   652893篇
皮肤病学   80637篇
神经病学   271535篇
特种医学   127921篇
外国民族医学   919篇
外科学   496821篇
综合类   65923篇
现状与发展   6篇
一般理论   1190篇
预防医学   257821篇
眼科学   76268篇
药学   250523篇
  13篇
中国医学   7438篇
肿瘤学   184750篇
  2021年   26481篇
  2019年   27428篇
  2018年   39352篇
  2017年   29948篇
  2016年   34229篇
  2015年   38367篇
  2014年   52056篇
  2013年   77868篇
  2012年   105484篇
  2011年   111581篇
  2010年   66370篇
  2009年   62570篇
  2008年   103045篇
  2007年   109588篇
  2006年   111161篇
  2005年   106498篇
  2004年   102130篇
  2003年   98310篇
  2002年   94793篇
  2001年   161066篇
  2000年   165305篇
  1999年   139055篇
  1998年   39210篇
  1997年   34687篇
  1996年   34902篇
  1995年   33690篇
  1994年   30680篇
  1993年   28768篇
  1992年   107346篇
  1991年   103306篇
  1990年   100476篇
  1989年   97113篇
  1988年   88793篇
  1987年   86704篇
  1986年   81633篇
  1985年   77673篇
  1984年   57653篇
  1983年   48581篇
  1982年   28564篇
  1979年   51230篇
  1978年   35726篇
  1977年   31073篇
  1976年   28210篇
  1975年   30618篇
  1974年   36059篇
  1973年   34494篇
  1972年   32556篇
  1971年   30278篇
  1970年   27877篇
  1969年   26917篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
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   
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