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   4069284篇
  免费   307941篇
  国内免费   10206篇
耳鼻咽喉   57503篇
儿科学   130479篇
妇产科学   111190篇
基础医学   568837篇
口腔科学   116989篇
临床医学   375754篇
内科学   789830篇
皮肤病学   91258篇
神经病学   338237篇
特种医学   158622篇
外国民族医学   1440篇
外科学   610433篇
综合类   91259篇
现状与发展   6篇
一般理论   1723篇
预防医学   325696篇
眼科学   94828篇
药学   301536篇
  11篇
中国医学   7984篇
肿瘤学   213816篇
  2018年   43735篇
  2017年   33648篇
  2016年   38227篇
  2015年   43132篇
  2014年   60743篇
  2013年   92195篇
  2012年   122540篇
  2011年   130026篇
  2010年   77964篇
  2009年   74513篇
  2008年   121980篇
  2007年   129594篇
  2006年   131314篇
  2005年   126963篇
  2004年   122345篇
  2003年   117954篇
  2002年   114772篇
  2001年   187109篇
  2000年   192597篇
  1999年   163344篇
  1998年   48519篇
  1997年   43304篇
  1996年   42941篇
  1995年   41631篇
  1994年   38659篇
  1993年   36171篇
  1992年   129797篇
  1991年   125581篇
  1990年   121382篇
  1989年   117272篇
  1988年   108392篇
  1987年   106786篇
  1986年   100858篇
  1985年   96622篇
  1984年   72666篇
  1983年   62058篇
  1982年   37375篇
  1981年   33632篇
  1979年   66786篇
  1978年   47257篇
  1977年   40041篇
  1976年   37514篇
  1975年   39610篇
  1974年   48008篇
  1973年   45837篇
  1972年   43143篇
  1971年   39949篇
  1970年   37326篇
  1969年   35294篇
  1968年   32467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