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   2730032篇
  免费   192319篇
  国内免费   7950篇
耳鼻咽喉   36314篇
儿科学   91002篇
妇产科学   76064篇
基础医学   382953篇
口腔科学   73910篇
临床医学   246390篇
内科学   540639篇
皮肤病学   65827篇
神经病学   222375篇
特种医学   107817篇
外国民族医学   819篇
外科学   408933篇
综合类   51352篇
现状与发展   5篇
一般理论   983篇
预防医学   208964篇
眼科学   60025篇
药学   198052篇
  10篇
中国医学   5434篇
肿瘤学   152433篇
  2019年   20988篇
  2018年   32698篇
  2017年   26326篇
  2016年   29181篇
  2015年   33740篇
  2014年   44099篇
  2013年   63424篇
  2012年   88474篇
  2011年   88591篇
  2010年   52949篇
  2009年   52279篇
  2008年   80923篇
  2007年   86280篇
  2006年   88183篇
  2005年   91668篇
  2004年   90970篇
  2003年   83985篇
  2002年   76109篇
  2001年   130513篇
  2000年   132142篇
  1999年   113362篇
  1998年   31600篇
  1997年   28091篇
  1996年   28412篇
  1995年   27605篇
  1994年   25268篇
  1993年   23559篇
  1992年   88939篇
  1991年   85754篇
  1990年   83134篇
  1989年   80318篇
  1988年   73484篇
  1987年   71964篇
  1986年   67382篇
  1985年   63854篇
  1984年   47267篇
  1983年   39899篇
  1982年   23115篇
  1981年   20498篇
  1979年   41618篇
  1978年   29039篇
  1977年   24510篇
  1976年   22555篇
  1975年   24545篇
  1974年   29037篇
  1973年   27383篇
  1972年   25775篇
  1971年   23985篇
  1970年   22071篇
  1969年   21277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.

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.
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   
6.
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