全文获取类型
收费全文 | 299篇 |
免费 | 8篇 |
国内免费 | 43篇 |
专业分类
系统科学 | 23篇 |
丛书文集 | 2篇 |
教育与普及 | 5篇 |
理论与方法论 | 3篇 |
现状及发展 | 72篇 |
综合类 | 244篇 |
自然研究 | 1篇 |
出版年
2023年 | 6篇 |
2022年 | 9篇 |
2021年 | 12篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 8篇 |
2014年 | 13篇 |
2013年 | 11篇 |
2012年 | 13篇 |
2011年 | 10篇 |
2010年 | 16篇 |
2009年 | 16篇 |
2008年 | 24篇 |
2007年 | 21篇 |
2006年 | 24篇 |
2005年 | 24篇 |
2004年 | 23篇 |
2003年 | 29篇 |
2002年 | 14篇 |
2001年 | 10篇 |
2000年 | 12篇 |
1999年 | 13篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有350条查询结果,搜索用时 15 毫秒
261.
用LabVIEW和数据采集卡实现信号检测 总被引:1,自引:0,他引:1
介绍了虚拟仪器在铁路信号检测中的应用 .具体内容包括检测系统的功能、硬件组成和软件结构 .文中同时介绍了LabVIEW和数据采集卡 . 相似文献
262.
S. K. Grant 《Cellular and molecular life sciences : CMLS》2009,66(7):1163-1177
Protein kinase inhibitors represent an important and still emerging class of targeted therapeutic agents. Drug discovery and
development strategies have explored numerous approaches to target the inhibition of protein kinase signaling. This review
will highlight some of the strategies that have led to the successful clinical development of therapeutic protein kinase inhibitors,
particularly as anticancer drugs. Some notable advances have been made in the development of novel protein and oligonucleotide-based
biologics that target growth factor or receptor tyrosine kinases. Also, advances have been made in the rational design of
small-molecule inhibitors that target unique kinase conformational forms and binding sites, and have specific kinase selectivity
profiles. A review will also be given of some of the potential clinical toxicities and adverse side-effects associated with
these kinase-targeted drugs. Therapeutic protein kinase inhibitors have been highly beneficial to cancer patients and offer
the promise of future therapies for other diseases as well.
Received 02 September 2008; received after revision 13 October 2008; accepted 15 October 2008 相似文献
263.
Ca2+ influx evoked across the plasma membrane upon internal store depletion is essential for a myriad of cellular functions including
gene expression, cell proliferation, differentiation and even apoptosis. Darier’s disease (DD), an autosomal dominant inherited
disorder of the skin, arising due to mutations in the isoform 2 of the sarco (endo) plasmic reticulum Ca2+ ATPase (SERCA2), exemplifies an anomaly of Ca2+ signaling disturbances. Owing to loss of function mutations in SERCA2, keratinocytes in DD patients have a reduced pool of
endoplasmic reticulum (ER) Ca2+. Importantly, the status of ER Ca2+ is critical for the activation of a class of plasma membrane Ca2+ channels referred to as store operated Ca2+ channels (SOCs). The widely expressed transient receptor potential (TRP) family of channels is proposed to be SOCs. In this
review we discuss DD from the viewpoint of Ca2+ signaling and present a potential role for TRPC1 in the disease pathogenesis.
Received 30 August 2007; received after revision 17 October 2007; accepted 6 November 2007 相似文献
264.
Stem cells are a powerful resource for cell-based transplantation therapies in osteodegenerative disorders, but before some kinds of stem cells can be applied clinically, several aspects of their expansion and differentiation need to be better controlled. Wnt molecules and members of the Wnt signaling cascade have been ascribed a role in both these processes in vitro as well as normal development in vivo. However some results are controversial. In this review we will present the hypothesis that both canonical and non-canonical signaling are involved in mesenchymal cell fate regulation, such as adipogenesis, chondrogenesis and osteogenesis, and that in vitro it is a timely switch between the two that specifies the identity of the differentiating cell. We will specifically focus on the in vitro differentiation of adipocytes, chondrocytes and osteoblasts contrasting embryonic and mesenchymal stem cells as well as the role of Wnts in mesenchymal fate specification during embryogenesis. 相似文献
265.
Tang J Wu YM Zhao P Yang XM Jiang JL Chen ZN 《Cellular and molecular life sciences : CMLS》2008,65(18):2933-2942
Mechanism of HAb18G/CD147 underlying the metastasis process of human hepatoma cells has not been determined. In the present
study, we found that integrin α3β1 colocalizes with HAb18G/CD147 in human 7721 hepatoma cells. The enhancing effect of HAb18G/CD147
on adhesion, invasion capacities and matrix metalloproteinases (MMPs) secretion was decreased by integrin α3β1 antibodies
(p<0.01). The expressions of integrin downstream molecules including focal adhesion kinase (FAK), phospho-FAK (p-FAK), paxillin,
and phospho-paxillin (p-paxillin) were increased in human hepatoma cells overexpressing HAb18G/CD147. Deletion of HAb18G/CD147
reduces the quantity of focal adhesions and rearranges cytoskeleton. Wortmannin and LY294002, specific phosphatidylinositol
kinase (PI3K) inhibitors, reversed the effect of HAb18G/CD147 on the regulation of intracellular Ca2+ mobilization, significantly reducing cell adhesion, invasion and MMPs secretion potential (p<0.01). Together, these results suggest that HAb18G/CD147 enhances the invasion and metastatic potentials of human hepatoma
cells via integrin α3β1-mediated FAK-paxillin and FAKPI3K-Ca2+ signal pathways.
Received 5 June 2008; received after revision 16 July 2008; accepted 23 July 2008 相似文献
266.
In cases of animal mimicry, the receiver of the signal learns the truth that he is either dealing with the real thing or with a mimic. Thus, despite being a prototypical example of animal deception, mimicry does not seem to qualify as deception on the traditional definition, since the receiver is not actually misled. We offer a new account of propositional content in sender-receiver games that explains how the receiver is misled (and deceived) by mimicry. We show that previous accounts of deception, and of propositional content, give incorrect results about whether certain signals are deceptive. 相似文献
267.
Role of heregulin in human cancer 总被引:3,自引:0,他引:3
Breuleux M 《Cellular and molecular life sciences : CMLS》2007,64(18):2358-2377
Heregulin (HRG) is a soluble secreted growth factor, which, upon binding and activation of ErbB3 and ErbB4 transmembrane receptor
tyrosine kinases, is involved in cell proliferation, invasion, survival and differentiation of normal and malignant tissues.
The HRG gene family consists of four members: HRG-1, HRG-2, HRG-3 and HRG-4, of which a multitude of different isoforms are synthesized by alternative exon splicing, showing various tissue distribution
and biological activities. Disruption of the physiological balance between HRG ligands and their ErbB receptors is implicated
in the formation of a variety of human cancers. The general mechanisms involved in HRG-induced tumorigenesis is discussed.
Received 8 March 2007; received after revision 6 May 2007; accepted 9 May 2007 相似文献
268.
Savaskan NE Rocha L Kotter MR Baer A Lubec G van Meeteren LA Kishi Y Aoki J Moolenaar WH Nitsch R Bräuer AU 《Cellular and molecular life sciences : CMLS》2007,64(2):230-243
Autotaxin is a secreted cell motility-stimulating exo-phosphodiesterase with lysophospholipase D activity that generates bioactive
lysophosphatidic acid. Lysophosphatidic acid has been implicated in various neural cell functions such as neurite remodeling,
demyelination, survival and inhibition of axon growth. Here, we report on the in vivo expression of autotaxin in the brain during development and following neurotrauma. We found that autotaxin is expressed in
the proliferating subventricular and choroid plexus epithelium during embryonic development. After birth, autotaxin is mainly
found in white matter areas in the central nervous system. In the adult brain, autotaxin is solely expressed in leptomeningeal
cells and oligodendrocyte precursor cells. Following neurotrauma, autotaxin is strongly up-regulated in reactive astrocytes
adjacent to the lesion. The present study revealed the cellular distribution of autotaxin in the developing and lesioned brain
and implies a function of autotaxin in oligodendrocyte precursor cells and brain injuries.
Received 18 September 2006; received after revision 30 October 2006; accepted 4 December 2006 相似文献
269.
Decoding the Hedgehog signal in animal development 总被引:4,自引:0,他引:4
The Hedgehog (Hh) family of secreted proteins plays essential roles in a myriad of developmental processes via a complex signaling
cascade conserved in species ranging from insects to mammals. In many developmental contexts, Hh acts as long-range morphogen
to control distinct cellular outcomes as a function of its concentration. Here we review the current understanding of the
Hh signaling mechanisms that govern the establishment of the Hh gradient and the transduction of the Hh signal with an emphasis
on the intracellular signaling cascade from the receptor to the nuclear effector. We discuss how graded Hh signals are transduced
to govern distinct developmental outcomes.
Received 28 October 2005; received after revision 6 February 2006; accepted 15 February 2006 相似文献
270.