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   2861557篇
  免费   199818篇
  国内免费   8055篇
耳鼻咽喉   37475篇
儿科学   93837篇
妇产科学   77691篇
基础医学   401164篇
口腔科学   75756篇
临床医学   256071篇
内科学   574985篇
皮肤病学   68646篇
神经病学   239563篇
特种医学   108772篇
外国民族医学   836篇
外科学   425045篇
综合类   51950篇
现状与发展   5篇
一般理论   1024篇
预防医学   221753篇
眼科学   61423篇
药学   205972篇
  8篇
中国医学   6004篇
肿瘤学   161450篇
  2021年   24307篇
  2019年   25041篇
  2018年   43967篇
  2017年   33316篇
  2016年   38345篇
  2015年   34795篇
  2014年   46619篇
  2013年   69511篇
  2012年   97449篇
  2011年   107036篇
  2010年   64825篇
  2009年   59664篇
  2008年   99041篇
  2007年   106380篇
  2006年   98184篇
  2005年   95884篇
  2004年   92141篇
  2003年   89447篇
  2002年   85105篇
  2001年   132250篇
  2000年   135368篇
  1999年   114004篇
  1998年   32455篇
  1997年   28991篇
  1996年   29082篇
  1995年   28201篇
  1994年   25811篇
  1993年   24080篇
  1992年   87267篇
  1991年   83560篇
  1990年   80692篇
  1989年   77759篇
  1988年   71123篇
  1987年   69566篇
  1986年   65003篇
  1985年   61928篇
  1984年   46057篇
  1983年   38892篇
  1982年   23128篇
  1981年   20448篇
  1979年   40001篇
  1978年   28185篇
  1977年   23916篇
  1976年   22097篇
  1975年   23490篇
  1974年   27640篇
  1973年   26218篇
  1972年   24543篇
  1971年   22719篇
  1970年   20975篇
排序方式: 共有10000条查询结果,搜索用时 328 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