腺病毒介导血管内皮细胞生长因子基因体外转染骨髓间充质干细胞

【目的】探讨腺病毒介导血管内皮细胞生长因子(VEGF165)基因转染大鼠骨髓间充质干细胞(MSCs)后目的基因表达情况及对MSCs增殖分化的影响。【方法】构建含VEGF基因的腺病毒表达载体,利用贴壁法分离培养MSCs后,用荧光显微镜和流式细胞仪检测转染效果和转染率,用免疫组化、Western-Blot和ELISA方法分别检测VEGF基因转染MSCs后VEGF的表达情况。【结果】腺病毒介导的VEGF基因对于MSCs具有很高的转染效率,转染效率与病毒感染复制数(multiplicyties of infection,MOI)具有量效关系。MOI为150倍时,转染效率>95%,转染VEGF后,MSCs可有效表达VEGF,9d时达到表达高峰(1125pg/mL),13d后仍可检测到VEGF的表达。转染VEGF对MSCs的增殖分化没有明显影响。【结论】腺病毒介导的VEGF基因可以有效的转染MSCs,MSCs是一种理想的基因载体细胞,其携带的VEGF基因可获得较高的表达水平

Capacity Modulation Device with Changing Concentration of Mixture Refrigerant:A State-of-the-art Review

Air source heat pump is widely used, and a capacity modulation with concentration of mixture refrigerant is a new type modulation of environment protection and energy conservation. In this paper, the state of the art of existing variable concentration devices with mixture refrigerant is presented and their types are described according to their locations in the system. The analysis results indicate that the variable concentration device should be set at the outlet of liquid refrigerant in order to change concentration of mixture refrigerant in air source heat pump. Moreover, a rectification section is more effective to change concentration than a gasliquid separator or liquid reservoir, and the middle throttling apparatus should be an electronic regulation device other than a capillary tube. The improvement and application of variable concentration devices in air source heat pumps are also discussed

The Role of Microorganisms in the Geochemical Iron Cycle

铁元素虽然只在地壳含量中位列第4,但却是地球上分布最广的变价金属元素之一,微生物介导的铁循环及其与生源要素碳、氮、氧和硫等耦合的氧化还原反应是微生物地球化学循环的重要驱动力.由于铁循环过程中氧化态三价铁Fe(Ⅲ)在环境p H条件下大多以不溶状态存在,因而由其参与的地球化学循环进程通常较为缓慢.研究表明,微生物在铁元素的地球化学循环过程中起着举足轻重的作用,并在该过程中参与矿物的生成与转化.近年来的最新研究发现,参与地球化学铁循环的微生物之间,微生物与矿物之间,以及矿物介导的微生物之间存在着多样的相互作用,而含铁矿物介导的微生物胞外电子传递机制是其中最受瞩目的研究热点.本文综述了微生物介导的地球..

翡翠贻贝足蛋白作为生物黏合剂的提取及应用

贻贝黏附蛋白作为一种潜在的环保性生物黏合剂,在医学以及水下应用等方面具有潜在价值。为了研究翡翠贻贝足部黏附蛋白(Pvfp)作为生物黏合剂的黏附特性,利用酸提取法提取Pvfp,并对其进行不同材料表面包被能力分析,以石英晶体微天平(QCM)检测蛋白在金表面的黏附量,分析该蛋白对细胞及组织的黏附能力以及细胞毒性。对不同材料表面包被能力以及QCM分析结果显示,Pvfp具有与Cell-TakTM相似甚至更佳的吸附能力;细胞黏附结果显示,Pvfp具有比Cell-TakTM和PLL(poly-L-lysine)更强的细胞黏附能力;对Hela细胞和293T细胞的毒性分析结果显示,Pvfp没有细胞毒性;组织黏附结果显示,Pvfp可以黏接断裂的小鼠股骨;黏接聚氯乙烯材料和黏接猪的断裂股骨实验结果表明,Pvfp具有比医用生物蛋白胶更强的抗张强度。提示,Pvfp蛋白可能作为有效的细胞和组织黏合剂而广泛应用于生物技术领域,并在临床应用生物黏合剂中具有潜在应用价值

Instability analysis of non-linear unmanned model helicopter control

针对无人机的飞行安全这一典型的系统工程问题,从目前国际惯用的非线性控制和辨识建模的角度出发,通过建立波动信息能量函数模型并结合模糊评价理论,量化分析了dfT变换对无人机系统建模和控制的不稳定性影响;通过对无人机非线性运动模型的分析,说明了该模型中各参数的不稳定关系和不稳定特征,提出了符合SHIlnIkOV定理的三阶非线性模型;通过构造综合影响函数和进行参数配置,确定了无人机非线性运动模型的若干鞍焦点和异宿轨道,从而找到了该系统的若干混沌运动轨道.最后通过仿真证明了直升机非线性运动模型的混沌运动特征和运用dfT辨识模型进行控制的条件下出现无人机不稳定性现象,说明了无人机非线性运动模型混沌运动的存在性及dfT变换中的高阶能量损失和参数配置方式的共同作用模式可构成无人机系统不稳定性的条件.For a typical system engineering problem of unmanned airplane vehicle flight safety,the paper quantitatively analysised the instability effects between the DFT transform and modeling control of the UAV system through the establishment of fluctuation energy function and the combinations of fuzzy evaluation theory from the current international practices perspective of nonlinear controlling and modeling identification,gave out the instability relationship between the parameters and their instability characteristic of the nonlinear motion model of helicopter through the analysis of the modeling process,raised the three-order nonlinear model in line with Shilnikov theorem,showed the possibility of the existence of chaotic orbits.By constructing the comprehensive effect function and parameter configuration,a number of saddle-focus and heteroclinic orbits were discovered.Finally,the chaotic motion characteristics of the non-linear model were proven by stimulation,and the conditions and causes of the existence of the instability were listed by DFT identification model.Additionally,the existence of chaos in a UAV nonlinear motion model was proven.The common mode action of high-level energy loss in DFT transformation and the configuration of parameters constitute the conditions under which a UAV system is not stable.国家985工程二期信息平台建设(0X0007);国家自然科学基金资助项目(61070151);福建省自然科学基金资助项目(2010J01353

Relevant relationship between IUD and endometrial polypus

目的:研究宫内节育器(InTrAuTEruS dEVICE,Iud)与子宫内膜息肉的相关性。方法:统计2004年5月--2007年5月在厦门大学附属中山医院行宫腔镜取环并经病理检查确诊Iud合并子宫内膜息肉病例,分析Iud与子宫内膜息肉的相关敏感因素。结果:1357例宫腔镜取环者Iud合并子宫内膜息肉285例,占21%,患者对金属皮带扣或金饰物过敏,经阴道分娩和人工流产且中位子宫患者的发病率较高,息肉好发于Iud的周围。放环时间15年以上,Iud变形、下移和长锈斑的比例均较高。结论:放置Iud且有息肉形成高危因素的患者应及时行宫腔镜检查,并行诊刮术或子宫内膜息肉电切术、取环术。Objective:To study relevant relationship between IUD and endometrial polyps(EMP).Methods:The cases who removed IUD and EMP by hysteroscopic operation and diagnosed by pathological examination were analyzed in Xiamen Zhongshan Hoapital from may 2004 to may 2007,and the related factors of IUD and EMP were analyzed.Results:of 1357 cases who removed IUD by hysteroscopic operation,the cases who had EMP was 21%(285/1357).EMP growed around IUD in cases whose uteri were middle position.Vaginal labor and artificial abortion and allergic to metal including the metal buckle and gold ornaments were high risk factors.Conclusion:The cases with IUD who had risk factors of endometrial polypus formation need do hysteroscopic operation and remove IUD

Structure and Function of Marine Mussel Adhesive Proteins

海洋贻贝粘附蛋白具有高强度、高韧性和防水性,以及极强的黏附基体的功能,这与其特殊的分子结构、多巴(DOPA)介导的链间交联和与底材之间的相互作用方式有关,并且,它还具有很好的生物相容性和可降解性,是一类极具优势和潜力的生物胶黏剂.本文主要就粘附蛋白分子的结构和功能、粘附蛋白的粘附机理以及有关粘附蛋白生物粘剂等问题对其进行综述.The characteristics of marine mussel adhesive proteins,such as strong intensity, tenacity,moisture-resistance and strong adhesive ability,are due to their peculiarity of molecular structure, cross-linking of bonds and the interaction between proteins and substratum mediated by DOPA. Furthermore, they are biocompatible and biodegradable. Therefore, marine mussel adhesive proteins may be a preponderant and potential bio-adhesive. This review mainly focused on structure and function of adhesive protein molecule, adhesive mechanism of adhesive protein, and the potential of adhesive protein to be bio-adhesive.福建省青年科技人才创新项目(No.2004J022);; 国家自然科学基金(No.30600147)资助~

不停跳心内直视手术对心肌细胞凋亡的影响

【目的】评价不停跳体外循环心内直视手术对心肌细胞凋亡的影响和探讨其临床意义。【方法】停跳心内直视手术患者25例（A组）,不停跳心内直视手术患者20例（B组）,取心肌组织作TUNEL细胞凋亡检测,比较分析术前和术后心肌细胞凋亡率并参照围手术期肌钙蛋白T（cTnT）检测。【结果】两组患者均无低心输出量综合征的发生。心肌细胞凋亡指数A组（0.003±0.002）和B组（0.004±0.003）术前无明显差别（P〉0.05）;术后心肌细胞凋亡指数A组（0.012±0.008,P〈0.001）和B组（0.006±0.004,P〈0.001）均高于术前;A、B两组术后心肌细胞凋亡指数差别有明显差别（P〈0.05）。围手术期cTnT水平A组在CPB末和术后2 h明显高于B组（P〈0.05）。【结论】本实验提示不停跳体外循环心内直视手术引起心肌细胞凋亡和心肌损害小于停跳手术