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   3361009篇
  免费   245630篇
  国内免费   8380篇
耳鼻咽喉   45379篇
儿科学   110943篇
妇产科学   94141篇
基础医学   478756篇
口腔科学   93810篇
临床医学   310112篇
内科学   655678篇
皮肤病学   78933篇
神经病学   275929篇
特种医学   128678篇
外国民族医学   964篇
外科学   495544篇
综合类   68982篇
现状与发展   7篇
一般理论   1450篇
预防医学   265115篇
眼科学   75940篇
药学   246019篇
  12篇
中国医学   6465篇
肿瘤学   182162篇
  2019年   26483篇
  2018年   36827篇
  2017年   28372篇
  2016年   32465篇
  2015年   36887篇
  2014年   50803篇
  2013年   77022篇
  2012年   102469篇
  2011年   108715篇
  2010年   65072篇
  2009年   62548篇
  2008年   102063篇
  2007年   108594篇
  2006年   109827篇
  2005年   105911篇
  2004年   101927篇
  2003年   98227篇
  2002年   94955篇
  2001年   156380篇
  2000年   160033篇
  1999年   135168篇
  1998年   39186篇
  1997年   34994篇
  1996年   35442篇
  1995年   34106篇
  1994年   31444篇
  1993年   29501篇
  1992年   106290篇
  1991年   103195篇
  1990年   99904篇
  1989年   96445篇
  1988年   88900篇
  1987年   87161篇
  1986年   82177篇
  1985年   78291篇
  1984年   58869篇
  1983年   50135篇
  1982年   29851篇
  1981年   26834篇
  1979年   52938篇
  1978年   37890篇
  1977年   32085篇
  1976年   29686篇
  1975年   31828篇
  1974年   37962篇
  1973年   36621篇
  1972年   34507篇
  1971年   32088篇
  1970年   29823篇
  1969年   28482篇
排序方式: 共有10000条查询结果,搜索用时 37 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.

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   
3.
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