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   121856篇
  免费   8141篇
  国内免费   546篇
耳鼻咽喉   1585篇
儿科学   3371篇
妇产科学   1847篇
基础医学   15436篇
口腔科学   2810篇
临床医学   11109篇
内科学   27993篇
皮肤病学   2383篇
神经病学   11389篇
特种医学   4691篇
外国民族医学   1篇
外科学   19916篇
综合类   901篇
一般理论   196篇
预防医学   8763篇
眼科学   2285篇
药学   7180篇
中国医学   233篇
肿瘤学   8454篇
  2023年   897篇
  2022年   1335篇
  2021年   3801篇
  2020年   2031篇
  2019年   3411篇
  2018年   4335篇
  2017年   2886篇
  2016年   3035篇
  2015年   3366篇
  2014年   4495篇
  2013年   6000篇
  2012年   9319篇
  2011年   9561篇
  2010年   5232篇
  2009年   4432篇
  2008年   7921篇
  2007年   7776篇
  2006年   7543篇
  2005年   7456篇
  2004年   6772篇
  2003年   6183篇
  2002年   5697篇
  2001年   1634篇
  2000年   1736篇
  1999年   1568篇
  1998年   1030篇
  1997年   782篇
  1996年   663篇
  1995年   617篇
  1994年   496篇
  1993年   501篇
  1992年   682篇
  1991年   562篇
  1990年   542篇
  1989年   458篇
  1988年   417篇
  1987年   387篇
  1986年   414篇
  1985年   384篇
  1984年   425篇
  1983年   358篇
  1982年   362篇
  1981年   354篇
  1980年   275篇
  1979年   183篇
  1978年   209篇
  1977年   205篇
  1975年   161篇
  1974年   180篇
  1973年   162篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
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   
3.
4.
5.
6.
7.
Among the chief limitations in achieving early detection and control of animal‐origin influenza of pandemic potential in high‐risk livestock populations is the existing lag time between sample collection and diagnostic result. Advances in molecular diagnostics are permitting deployment of affordable, rapid, highly sensitive, and specific point‐of‐capture assays, providing opportunities for targeted surveillance driving containment strategies with potentially compelling returns on investment. Interrupting disease transmission at source holds promise of disrupting cycles of animal‐origin influenza incursion to endemicity and limiting impact on animal production, food security, and public health. Adoption of new point‐of‐capture diagnostics should be undertaken in the context of promoting robust veterinary services systems and parallel support for operationalizing pre‐authorized plans and communication strategies that will ensure that the full potential of these new platforms is realized.  相似文献   
8.
9.
10.
Chondrocytes are the main cells in the extracellular matrix (ECM) of articular cartilage and possess a highly differentiated phenotype that is the hallmark of the unique physiological functions of this specialised load-bearing connective tissue. The plasma membrane of articular chondrocytes contains a rich and diverse complement of membrane proteins, known as the membranome, which defines the cell surface phenotype of the cells. The membranome is a key target of pharmacological agents and is important for chondrocyte function. It includes channels, transporters, enzymes, receptors, and anchors for intracellular, cytoskeletal and ECM proteins and other macromolecular complexes. The chondrocyte channelome is a sub-compartment of the membranome and includes a complete set of ion channels and porins expressed in these cells. Many of these are multi-functional proteins with “moonlighting” roles, serving as channels, receptors and signalling components of larger molecular assemblies. The aim of this review is to summarise our current knowledge of the fundamental aspects of the chondrocyte channelome, discuss its relevance to cartilage biology and highlight its possible role in the pathogenesis of osteoarthritis (OA). Excessive and inappropriate mechanical loads, an inflammatory micro-environment, alternative splicing of channel components or accumulation of basic calcium phosphate crystals can result in an altered chondrocyte channelome impairing its function. Alterations in Ca2+ signalling may lead to defective synthesis of ECM macromolecules and aggravated catabolic responses in chondrocytes, which is an important and relatively unexplored aspect of the complex and poorly understood mechanism of OA development.  相似文献   
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