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   4016876篇
  免费   291460篇
  国内免费   9047篇
耳鼻咽喉   55913篇
儿科学   131865篇
妇产科学   110815篇
基础医学   574150篇
口腔科学   112193篇
临床医学   370485篇
内科学   775304篇
皮肤病学   92984篇
神经病学   326270篇
特种医学   152277篇
外国民族医学   1141篇
外科学   601494篇
综合类   83729篇
现状与发展   15篇
一般理论   1620篇
预防医学   314795篇
眼科学   93690篇
药学   296496篇
  15篇
中国医学   7860篇
肿瘤学   214272篇
  2019年   32358篇
  2018年   44729篇
  2017年   33913篇
  2016年   38985篇
  2015年   43909篇
  2014年   61355篇
  2013年   92931篇
  2012年   125211篇
  2011年   132996篇
  2010年   79958篇
  2009年   76064篇
  2008年   124452篇
  2007年   132292篇
  2006年   134208篇
  2005年   129466篇
  2004年   124597篇
  2003年   120120篇
  2002年   116118篇
  2001年   183250篇
  2000年   188123篇
  1999年   159061篇
  1998年   47283篇
  1997年   41530篇
  1996年   41699篇
  1995年   40063篇
  1994年   36797篇
  1993年   34627篇
  1992年   124779篇
  1991年   120939篇
  1990年   117644篇
  1989年   114005篇
  1988年   104929篇
  1987年   102820篇
  1986年   96825篇
  1985年   92830篇
  1984年   69386篇
  1983年   59085篇
  1982年   35245篇
  1981年   31734篇
  1979年   62997篇
  1978年   44789篇
  1977年   37824篇
  1976年   35603篇
  1975年   38014篇
  1974年   45332篇
  1973年   43206篇
  1972年   40647篇
  1971年   38192篇
  1970年   35178篇
  1969年   33851篇
排序方式: 共有10000条查询结果,搜索用时 31 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