Caristi不动点定理与Banach压缩原理的等价性

作者证明了在一定条件下存在某一等价度量d*,使得满足Caristi不动点定理条件的映射F关于d*是Banach压缩映射,因此,Caristi不动点定理在一定条件下与Banach压缩映射原理等价.     

二灰稳定碎石半刚性基层性能的试验研究

由于结构设计不当,半刚性基层的优越性往往不能充分发挥,从而导致路面的早期破坏;同时由于其早期强度低,使得施工养护难度增大。文章对二灰稳定碎石半刚性基层两种结构进行材料选择和配合比的优化设计,试验表明在二灰稳定碎石半刚性基层材料中加入适量的水泥能提高混合料的早期强度和总体强度,而且能减少混合料的干缩、温缩裂缝。     

小型猪骨髓间充质干细胞经心导管冠状动脉移植及其迁移和分化的研究

目的建立小型猪心导管介入冠状动脉治疗模型,为骨髓间充质于细胞（MSCs）移植治疗心血管疾病提供新的方法,观察骨髓间充质干细胞经心导管介入冠状动脉移植后在心肌内的迁移及分化。方法选用冠状动脉解剖生理特点与人类相似的小型猪,应用心导管介入技术将体外培养扩增的小型猪自体MSCs移植进入左冠状动脉前降支,用免疫荧光检测即刻移植和移植后6W移植细胞的肌钙蛋白T（cTnT）、缝隙连接蛋白43（Cx43）、anti－Ⅷfactor的表达。结果成功的完成了小型猪心导管介入冠状动脉进行自体骨髓间充质干细胞移植。移植细胞存活,向心肌组织迁移,并向心肌细胞和毛细血管方向分化。结论该方法稳定,技术先进。可进行准确的定位和动态观测,为临床应用提供了一个可靠的技术平台。MSCs移植后在心肌内发生迁移及分化。     

Differential regulation of collagen types I and III expression in cardiac fibroblasts by AGEs through TRB3/MAPK signaling pathway

Advanced glycation end products (AGEs) play an important role in collagen deposition in diabetic cardiomyopathy. TRB3, a mammalian homolog of Drosophila tribbles, functions to increase glucose intolerance and regulates cell proliferation. We demonstrated that AGEs induce collagen type I expression but inhibit collagen type III expression, accompanied by increased TRB3 expression. Furthermore, the collagen type I induced byAGEs was down-regulated after inhibition of ERK and p38-MAPK, the collagen type III reduced by AGEs was up-regulated after inhibition of ERK. The expression of collagen types I and III regulated by AGEs through MAPK was partly reversed after treatment with TRB3 siRNA. It suggests that the TRB3/MAPK signaling pathway participates in the regulation of collagen types I and III by AGEs and may provide new therapeutic strategies for diabetic cardiomyopathy. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Received 08 May 2008; received after revision 25 June 2008; accepted 22 July 2008 M. Tang, M. Zhong: These two authors contributed equally to this work.     

Effects of constitutively active GTPases on fibroblast behavior

The GTP-binding proteins RhoA, Cdc42 and Rac1 regulate the organization and turnover of the cytoskeleton and cell-matrix adhesions, structures bridging cells to their support, and translating forces, external or generated within the cell. To investigate the specific requirements of Rho GTPases for biomechanical activities of clonal cell populations, we compared side-by-side stable lines of human fibroblasts expressing constitutively active (CA) RhoA, Cdc42 or Rac1. There was no marked effect of any CA GTPase on cell adhesion to different extracellular matrix proteins. Cell spreading was CA Rho GTPase specific and independent of the extracellular matrix proteins allowing adhesion. Mechanical properties were dramatically restricted by CA RhoA on bi- and in tri-dimensional surroundings, were boosted by CA Rac1 on bi-dimensional surroundings only, and were not or marginally affected by CA Cdc42. In conclusion, the action of Rho GTPases appears to depend on the task cells are performing. Received 12 September 2005; received after revision 5 October 2005; accepted 1 November 2005     

收缩临界5连通图中平凡不可收缩边的新下界

证明n个顶点的收缩临界5连通图中至少有n 1条平凡不可收缩边.     

一类新型Stefan问题局部解的存在唯一性

讨论了一类单相Stefan问题解的存在唯一性.先将原问题转化为等价的积分方程问题,然后针对这个积分方程组定义一个由连续函数组成的Banach空间Ls及其上的一个映照F.通过证明F是Ls,M上的一个压缩映照,从而得到了积分方程局部解的存在唯一性.     

基于一种免疫遗传算法的BP网络设计

利用一种免疫遗传算法来辅助设计ＢＰ网络。此算法结合了遗传算法的随机全局搜索能力和生物免疫中抗体通过浓度的相互作用机制,实验结果证明了这种算法在设计神经网络时的有效性。     

基于混沌迁移策略的多种群差分进化算法

针对差分进化算法全局寻优效率偏低的弱点,提出了一种基于多种群的混沌迁移策略,用以改进常规差分进化算法。该策略通过在多种群并行进化过程中引入混沌迁移序列,引导个体进行种群间的迁移。利用混沌的遍历性和随机性,保证子种群之间能够进行充分高效的信息交换。仿真实验和PID控制参数优化应用表明:该算法具有很强的全局搜索能力,寻优效率高,有效地克服了基本差分算法的早熟收敛问题。     

重组Nkx2．5腺病毒的构建及心肌细胞感染实验

利用AdEasy腺病毒表达系统构建了Nkx2．5重组腺病毒．Nkx2．5基因克隆入pAdTrackcmv质粒,pAdTtrackcmv—Nkx2．5经Pme I线性化后转化含pAdEasy-1的BJ5183菌进行同源重组,以构建pAdEsay-Nkx2．5重组质粒．pAdEsay—Nkx2．5转染293A细胞进行病毒包装．以Ad-Nkx2．5重组腺病毒感染Hela及乳鼠心肌细胞,检测了Nkx2．5蛋白表达及对下游ANF和β-MHC基因的表达调控;并采用感染病毒的H9c2心肌细胞经H2O2处理建立细胞凋亡模型,采用噻唑蓝法和荧光染色法检测了细胞存活率和凋亡细胞的形态变化．结果显示,Nkx2．5过表达能抑制H2O2诱导的H9c2细胞凋亡．