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   3353730篇
  免费   246937篇
  国内免费   8538篇
耳鼻咽喉   46459篇
儿科学   112282篇
妇产科学   93083篇
基础医学   472307篇
口腔科学   92413篇
临床医学   304529篇
内科学   659407篇
皮肤病学   78474篇
神经病学   272867篇
特种医学   130168篇
外国民族医学   1282篇
外科学   505447篇
综合类   69746篇
现状与发展   6篇
一般理论   1224篇
预防医学   257194篇
眼科学   75764篇
药学   247415篇
  9篇
中国医学   6787篇
肿瘤学   182342篇
  2019年   25881篇
  2018年   36583篇
  2017年   28013篇
  2016年   32182篇
  2015年   36279篇
  2014年   50020篇
  2013年   75563篇
  2012年   101073篇
  2011年   107128篇
  2010年   64627篇
  2009年   61796篇
  2008年   100558篇
  2007年   107061篇
  2006年   108598篇
  2005年   104532篇
  2004年   101137篇
  2003年   97695篇
  2002年   94592篇
  2001年   161241篇
  2000年   165702篇
  1999年   140213篇
  1998年   40211篇
  1997年   35789篇
  1996年   35986篇
  1995年   34702篇
  1994年   32166篇
  1993年   30134篇
  1992年   110100篇
  1991年   106358篇
  1990年   103303篇
  1989年   99745篇
  1988年   91542篇
  1987年   89835篇
  1986年   84047篇
  1985年   80314篇
  1984年   60046篇
  1983年   50849篇
  1982年   29909篇
  1981年   26994篇
  1979年   53343篇
  1978年   37494篇
  1977年   31978篇
  1976年   29656篇
  1975年   31693篇
  1974年   37329篇
  1973年   35575篇
  1972年   33273篇
  1971年   30671篇
  1970年   28573篇
  1969年   26933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.

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