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   4064038篇
  免费   307750篇
  国内免费   10192篇
耳鼻咽喉   57466篇
儿科学   130320篇
妇产科学   111133篇
基础医学   568418篇
口腔科学   116924篇
临床医学   374860篇
内科学   788393篇
皮肤病学   91241篇
神经病学   337891篇
特种医学   158562篇
外国民族医学   1438篇
外科学   610067篇
综合类   91156篇
现状与发展   6篇
一般理论   1720篇
预防医学   324914篇
眼科学   94637篇
药学   301278篇
  11篇
中国医学   7981篇
肿瘤学   213564篇
  2018年   43672篇
  2017年   33598篇
  2016年   38169篇
  2015年   43075篇
  2014年   60667篇
  2013年   92094篇
  2012年   122393篇
  2011年   129864篇
  2010年   77869篇
  2009年   74455篇
  2008年   121864篇
  2007年   129448篇
  2006年   131211篇
  2005年   126842篇
  2004年   122236篇
  2003年   117850篇
  2002年   114691篇
  2001年   187069篇
  2000年   192555篇
  1999年   163311篇
  1998年   48489篇
  1997年   43272篇
  1996年   42912篇
  1995年   41621篇
  1994年   38637篇
  1993年   36156篇
  1992年   129768篇
  1991年   125533篇
  1990年   121345篇
  1989年   117255篇
  1988年   108364篇
  1987年   106758篇
  1986年   100828篇
  1985年   96588篇
  1984年   72644篇
  1983年   62045篇
  1982年   37361篇
  1981年   33617篇
  1979年   66758篇
  1978年   47241篇
  1977年   40031篇
  1976年   37505篇
  1975年   39597篇
  1974年   47993篇
  1973年   45818篇
  1972年   43113篇
  1971年   39930篇
  1970年   37315篇
  1969年   35282篇
  1968年   32457篇
排序方式: 共有10000条查询结果,搜索用时 457 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