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   3240426篇
  免费   230986篇
  国内免费   8385篇
耳鼻咽喉   44782篇
儿科学   107747篇
妇产科学   90256篇
基础医学   456735篇
口腔科学   89498篇
临床医学   294620篇
内科学   629425篇
皮肤病学   77976篇
神经病学   262645篇
特种医学   125574篇
外国民族医学   918篇
外科学   485009篇
综合类   65265篇
现状与发展   6篇
一般理论   1174篇
预防医学   244439篇
眼科学   73440篇
药学   243050篇
  13篇
中国医学   6999篇
肿瘤学   180226篇
  2019年   25489篇
  2018年   36029篇
  2017年   27889篇
  2016年   32221篇
  2015年   36161篇
  2014年   49641篇
  2013年   74250篇
  2012年   99055篇
  2011年   104725篇
  2010年   63011篇
  2009年   60180篇
  2008年   97605篇
  2007年   103843篇
  2006年   105712篇
  2005年   101335篇
  2004年   97359篇
  2003年   93935篇
  2002年   90693篇
  2001年   159354篇
  2000年   163406篇
  1999年   137521篇
  1998年   38866篇
  1997年   34383篇
  1996年   32461篇
  1995年   33327篇
  1994年   30383篇
  1993年   28484篇
  1992年   106260篇
  1991年   102394篇
  1990年   99535篇
  1989年   96292篇
  1988年   87938篇
  1987年   85953篇
  1986年   80852篇
  1985年   76927篇
  1984年   57053篇
  1983年   48021篇
  1982年   28183篇
  1981年   24970篇
  1979年   50472篇
  1978年   35175篇
  1977年   30484篇
  1976年   27690篇
  1975年   30052篇
  1974年   35303篇
  1973年   33699篇
  1972年   31840篇
  1971年   29601篇
  1970年   27209篇
  1969年   26195篇
排序方式: 共有10000条查询结果,搜索用时 109 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