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   2643497篇
  免费   191761篇
  国内免费   7709篇
耳鼻咽喉   35278篇
儿科学   86804篇
妇产科学   73365篇
基础医学   371920篇
口腔科学   71506篇
临床医学   238265篇
内科学   528479篇
皮肤病学   64159篇
神经病学   218344篇
特种医学   101108篇
外国民族医学   737篇
外科学   393892篇
综合类   50726篇
现状与发展   5篇
一般理论   986篇
预防医学   203319篇
眼科学   58095篇
药学   192550篇
  8篇
中国医学   5528篇
肿瘤学   147893篇
  2021年   21071篇
  2019年   21960篇
  2018年   31501篇
  2017年   23949篇
  2016年   27488篇
  2015年   30940篇
  2014年   41966篇
  2013年   62857篇
  2012年   84552篇
  2011年   88909篇
  2010年   53237篇
  2009年   50729篇
  2008年   82533篇
  2007年   87604篇
  2006年   89217篇
  2005年   85350篇
  2004年   82069篇
  2003年   79067篇
  2002年   76202篇
  2001年   129634篇
  2000年   132650篇
  1999年   111523篇
  1998年   31493篇
  1997年   28065篇
  1996年   28378篇
  1995年   27510篇
  1994年   25164篇
  1993年   23508篇
  1992年   85742篇
  1991年   82116篇
  1990年   79322篇
  1989年   76554篇
  1988年   69917篇
  1987年   68468篇
  1986年   64011篇
  1985年   60981篇
  1984年   45297篇
  1983年   38214篇
  1982年   22606篇
  1981年   20122篇
  1979年   39380篇
  1978年   27683篇
  1977年   23441篇
  1976年   21730篇
  1975年   23056篇
  1974年   27185篇
  1973年   25732篇
  1972年   24057篇
  1971年   22231篇
  1970年   20529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