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   4080703篇
  免费   308787篇
  国内免费   10248篇
耳鼻咽喉   57684篇
儿科学   130822篇
妇产科学   111477篇
基础医学   570268篇
口腔科学   117170篇
临床医学   376629篇
内科学   792253篇
皮肤病学   91496篇
神经病学   339514篇
特种医学   159118篇
外国民族医学   1438篇
外科学   612548篇
综合类   91354篇
现状与发展   7篇
一般理论   1760篇
预防医学   326434篇
眼科学   94953篇
药学   301999篇
  11篇
中国医学   8003篇
肿瘤学   214800篇
  2018年   44358篇
  2017年   34033篇
  2016年   38610篇
  2015年   43600篇
  2014年   61316篇
  2013年   92952篇
  2012年   123524篇
  2011年   131008篇
  2010年   78543篇
  2009年   74960篇
  2008年   122607篇
  2007年   130251篇
  2006年   131949篇
  2005年   127508篇
  2004年   122799篇
  2003年   118328篇
  2002年   115120篇
  2001年   187133篇
  2000年   192590篇
  1999年   163350篇
  1998年   48578篇
  1997年   43335篇
  1996年   42994篇
  1995年   41678篇
  1994年   38678篇
  1993年   36192篇
  1992年   129801篇
  1991年   125564篇
  1990年   121372篇
  1989年   117303篇
  1988年   108404篇
  1987年   106782篇
  1986年   100868篇
  1985年   96623篇
  1984年   72688篇
  1983年   62073篇
  1982年   37408篇
  1981年   33657篇
  1979年   66784篇
  1978年   47267篇
  1977年   40044篇
  1976年   37516篇
  1975年   39617篇
  1974年   48005篇
  1973年   45830篇
  1972年   43128篇
  1971年   39935篇
  1970年   37323篇
  1969年   35283篇
  1968年   32461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