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   5075201篇
  免费   371270篇
  国内免费   11351篇
耳鼻咽喉   73096篇
儿科学   163919篇
妇产科学   139280篇
基础医学   717066篇
口腔科学   148148篇
临床医学   474491篇
内科学   961593篇
皮肤病学   113499篇
神经病学   415143篇
特种医学   193644篇
外国民族医学   1765篇
外科学   757960篇
综合类   115599篇
现状与发展   16篇
一般理论   2239篇
预防医学   412114篇
眼科学   121922篇
药学   376951篇
  17篇
中国医学   9885篇
肿瘤学   259475篇
  2018年   54860篇
  2017年   41669篇
  2016年   47416篇
  2015年   53512篇
  2014年   75733篇
  2013年   115893篇
  2012年   155258篇
  2011年   165468篇
  2010年   99487篇
  2009年   94147篇
  2008年   154993篇
  2007年   164918篇
  2006年   166669篇
  2005年   161698篇
  2004年   155756篇
  2003年   149894篇
  2002年   145897篇
  2001年   221443篇
  2000年   227943篇
  1999年   193810篇
  1998年   59675篇
  1997年   52419篇
  1996年   51738篇
  1995年   49804篇
  1994年   46164篇
  1993年   43449篇
  1992年   154261篇
  1991年   150503篇
  1990年   146257篇
  1989年   141735篇
  1988年   131239篇
  1987年   129064篇
  1986年   122321篇
  1985年   117693篇
  1984年   88850篇
  1983年   76102篇
  1982年   46013篇
  1981年   41536篇
  1979年   83058篇
  1978年   59118篇
  1977年   50147篇
  1976年   47443篇
  1975年   50387篇
  1974年   60983篇
  1973年   58416篇
  1972年   55411篇
  1971年   51831篇
  1970年   48180篇
  1969年   45888篇
  1968年   42334篇
排序方式: 共有10000条查询结果,搜索用时 484 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.
Journal of Medical Ultrasonics - Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced...  相似文献   
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