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641.
642.
中朝板块北缘志留纪海岛的发现 总被引:2,自引:0,他引:2
在内蒙古达尔罕茂明安联合旗北部巴特敖包地区发现了志留纪的海岸带及其底栖无脊椎动物化石(层孔虫、日射与床板珊瑚等),证实当时该地发育一个位于中朝古板块北缘大陆棚上的小海岛,将其命名为巴特岛.该岛的基部由奥陶纪火成岩组成,长、短轴分别为610和200m,现今呈北东-南西向延伸.志留纪罗德洛世(距今约420Ma)的地层围绕该岛分布,产状向四周倾状.巴特岛的南缘(背风)发育皮壳状生物,栖息在火成岩顶面并被 相似文献
643.
GAO Zhi-wei Ho Daniel W. C. WANG Xian-lai LI Guang-quan . Tianjin University Tianjin China . City University of Hong Kong Kowloon Hong Kong China 《系统科学与系统工程学报(英文版)》2000,(1)
1 IntroductionConsider a singular decentralized control system of the formEx(t) =Ax(t) ∑Ni=1Biui(t)yi =Cix(t) ,i∈ N ={ 1 ,2 ,… ,N}(1 )where x(t)∈ Rn is the state vector,ui(t)∈ Rmi and yi(t)∈ Rpi are respectively the localcontrol input and measure outputvectors of the ith control channel.The matrix E may besingular,i.e.,rank(E) 相似文献
644.
纤溶酶原激活因子和抑制因子在早期胎盘中的表达及其功能 总被引:5,自引:1,他引:4
用原位杂交方法研究了人早期胎盘中组织型(t)和尿激酶型(u)纤溶酶原激活因子(PA)与其相应的抑制因子1型(PAI-1)和2型(PAI-2)mRNA的分布。结果表明:(1)在绒毛和蜕膜的血管壁,Rohrs和Nitabuch纹间的蜕膜中的大部分外细胞滋养层细胞沿绒毛盘、基底盘、绒毛叶间隔和绒毛膜的细胞滋养层细胞以及蜕膜的腺体细胞中都检测到tPA、uPA、PAI-1和PAI-2mRNA;(2)在基底绒 相似文献
645.
646.
The role of hypoxia-inducible factors in cancer 总被引:7,自引:0,他引:7
647.
648.
Advances in our understanding of cardiac development have fuelled research into cellular approaches to myocardial repair of
the damaged heart. In this collection of reviews we present recent advances into the basic mechanisms of heart development
and the resident and non-resident progenitor cell populations that are currently being investigated as potential mediators
of cardiac repair. Together these reviews illustrate that despite our current knowledge about how the heart is constructed,
caution and much more research in this exciting field is essential. The current momentum to evaluate the potential for cardiac
repair will in turn accelerate research into fundamental aspects of myocardial biology. 相似文献
649.
Samuel CS Hewitson TD Unemori EN Tang ML 《Cellular and molecular life sciences : CMLS》2007,64(12):1539-1557
The peptide hormone relaxin is emerging as a multi-functional factor in a broad range of target tissues including several
non-reproductive organs, in addition to its historical role as a hormone of pregnancy. This review discusses the evidence
that collectively demonstrates the many diverse and vital roles of relaxin: the homeostatic role of endogenous relaxin in
mammalian pregnancy and ageing; its gender-related effects; the therapeutic effects of relaxin in the treatment of fibrosis,
inflammation, cardioprotection, vasodilation and wound healing (angiogenesis) amongst other pathophysiological conditions,
and its potential mechanism of action. Furthermore, translational issues using experimental models (to humans) and its use
in various clinical trials, are described, each with important lessons for the design of future trials involving relaxin.
The diverse physiological and pathological roles for relaxin have led to the search for its significance in humans and highlight
its potential as a drug of the future.
Received 12 December 2006; received after revision 12 February 2007; accepted 15 March 2007 相似文献
650.
de Wit PJ 《Cellular and molecular life sciences : CMLS》2007,64(21):2726-2732
Plants have an innate immunity system to defend themselves against pathogens. With the primary immune system, plants recognize
microbe-associated molecular patterns (MAMPs) of potential pathogens through pattern recognition receptors (PRRs) that mediate
a basal defense response. Plant pathogens suppress this basal defense response by means of effectors that enable them to cause
disease. With the secondary immune system, plants have gained the ability to recognize effector-induced perturbations of host
targets through resistance proteins (RPs) that mediate a strong local defense response that stops pathogen growth. Both primary
and secondary immune responses in plants depend on germ line-encoded PRRs and RPs. During induction of local immune responses,
systemic immune responses also become activated, which predispose plants to become more resistant to subsequent pathogen attacks.
This review gives an update on recent findings that have enhanced our understanding of plant innate immunity and the arms
race between plants and their pathogens.
Received 24 June 2007; received after revision 18 July 2007; accepted 15 August 2007 相似文献