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   4064471篇
  免费   307775篇
  国内免费   10199篇
耳鼻咽喉   57485篇
儿科学   130327篇
妇产科学   111145篇
基础医学   568557篇
口腔科学   117096篇
临床医学   374863篇
内科学   788525篇
皮肤病学   91261篇
神经病学   337901篇
特种医学   158529篇
外国民族医学   1438篇
外科学   610016篇
综合类   91144篇
现状与发展   6篇
一般理论   1721篇
预防医学   324955篇
眼科学   94688篇
药学   301219篇
  11篇
中国医学   8003篇
肿瘤学   213555篇
  2018年   43715篇
  2017年   33633篇
  2016年   38197篇
  2015年   43111篇
  2014年   60722篇
  2013年   92127篇
  2012年   122458篇
  2011年   129936篇
  2010年   77888篇
  2009年   74479篇
  2008年   121894篇
  2007年   129502篇
  2006年   131249篇
  2005年   126886篇
  2004年   122270篇
  2003年   117863篇
  2002年   114709篇
  2001年   187060篇
  2000年   192541篇
  1999年   163300篇
  1998年   48486篇
  1997年   43266篇
  1996年   42907篇
  1995年   41615篇
  1994年   38637篇
  1993年   36150篇
  1992年   129757篇
  1991年   125528篇
  1990年   121335篇
  1989年   117245篇
  1988年   108362篇
  1987年   106746篇
  1986年   100820篇
  1985年   96579篇
  1984年   72640篇
  1983年   62030篇
  1982年   37355篇
  1981年   33616篇
  1979年   66747篇
  1978年   47233篇
  1977年   40026篇
  1976年   37493篇
  1975年   39595篇
  1974年   47989篇
  1973年   45811篇
  1972年   43108篇
  1971年   39925篇
  1970年   37309篇
  1969年   35275篇
  1968年   32452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.
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