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   4109477篇
  免费   307809篇
  国内免费   10165篇
耳鼻咽喉   57859篇
儿科学   132314篇
妇产科学   112024篇
基础医学   573974篇
口腔科学   117182篇
临床医学   377021篇
内科学   796476篇
皮肤病学   91466篇
神经病学   342946篇
特种医学   160870篇
外国民族医学   1438篇
外科学   618288篇
综合类   91471篇
现状与发展   6篇
一般理论   1719篇
预防医学   328353篇
眼科学   95121篇
药学   303976篇
  11篇
中国医学   7985篇
肿瘤学   216951篇
  2018年   49994篇
  2017年   38641篇
  2016年   44174篇
  2015年   43314篇
  2014年   60781篇
  2013年   92200篇
  2012年   124094篇
  2011年   135546篇
  2010年   82646篇
  2009年   77673篇
  2008年   127693篇
  2007年   136416篇
  2006年   131303篇
  2005年   128131篇
  2004年   123711篇
  2003年   119889篇
  2002年   116030篇
  2001年   187222篇
  2000年   192812篇
  1999年   163413篇
  1998年   48593篇
  1997年   43411篇
  1996年   42982篇
  1995年   41714篇
  1994年   38748篇
  1993年   36020篇
  1992年   129630篇
  1991年   125580篇
  1990年   121346篇
  1989年   117212篇
  1988年   108314篇
  1987年   106735篇
  1986年   100797篇
  1985年   96571篇
  1984年   72559篇
  1983年   61888篇
  1982年   37243篇
  1981年   33453篇
  1979年   66695篇
  1978年   47155篇
  1977年   39864篇
  1976年   37399篇
  1975年   39482篇
  1974年   47928篇
  1973年   45750篇
  1972年   43068篇
  1971年   39897篇
  1970年   37270篇
  1969年   35241篇
  1968年   32426篇
排序方式: 共有10000条查询结果,搜索用时 543 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