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   3521539篇
  免费   259122篇
  国内免费   8995篇
耳鼻咽喉   48344篇
儿科学   116695篇
妇产科学   96130篇
基础医学   494300篇
口腔科学   95897篇
临床医学   321765篇
内科学   693897篇
皮肤病学   80701篇
神经病学   289562篇
特种医学   135395篇
外国民族医学   1287篇
外科学   530123篇
综合类   72387篇
现状与发展   6篇
一般理论   1486篇
预防医学   272559篇
眼科学   80256篇
药学   259249篇
  14篇
中国医学   7037篇
肿瘤学   192566篇
  2021年   28175篇
  2019年   29299篇
  2018年   40408篇
  2017年   30939篇
  2016年   35325篇
  2015年   39971篇
  2014年   55626篇
  2013年   83649篇
  2012年   112905篇
  2011年   119610篇
  2010年   71833篇
  2009年   68178篇
  2008年   111616篇
  2007年   118724篇
  2006年   120257篇
  2005年   116174篇
  2004年   112069篇
  2003年   107879篇
  2002年   104260篇
  2001年   162625篇
  2000年   166720篇
  1999年   141749篇
  1998年   42274篇
  1997年   37514篇
  1996年   37428篇
  1995年   36059篇
  1994年   33329篇
  1993年   31152篇
  1992年   110900篇
  1991年   107054篇
  1990年   103920篇
  1989年   100340篇
  1988年   92160篇
  1987年   90415篇
  1986年   84618篇
  1985年   80915篇
  1984年   60860篇
  1983年   51610篇
  1982年   30863篇
  1981年   27932篇
  1979年   53820篇
  1978年   38021篇
  1977年   32422篇
  1976年   30077篇
  1975年   32039篇
  1974年   37675篇
  1973年   35858篇
  1972年   33527篇
  1971年   30845篇
  1970年   28738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