155 research outputs found

    Upconversion fluorescence silk mateirals

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    蚕丝材料是一种典型的天然高分子材料,蚕丝材料不仅具有良好的生物相容性,而且具有优异的机械性能和可控的降解速率,因而在生物医学领域有着广泛的应用。在蚕丝材料优良性能的基础上,对蚕丝材料进行光学功能化可以赋予其特定的光学性能,可以为新一代柔性器件的设计与制备提供更加丰富的选择。 本论文采用介观材料自组装的方法,向丝素蛋白蚕丝支架上组装了稀土上转换纳米颗粒,首次制备了上转换功能化的蚕丝支架。研究了上转换纳米颗粒的表面羟基修饰对生物支架的结构,光学,力学和生物性能的影响,发现表面包有PEG和SiO2的上转换纳米颗粒可以与丝素蛋白中的羰基产生相互作用,从而使蚕丝支架具备均匀、稳定的上转换荧光功能。增加...As a typical class of soft materials, Bombyx mori silk fibroin (SF) has exhibited promising properties in biomedical applications due to excellent biocompatibility, remarkable mechanical strength and controllable biodegradability. To functionalize SF materials with some additional properties will provide us with vast opportunities in fabricating SF devices of next generation. To achieve this goa...学位:理学硕士院系专业:材料学院_高分子化学与物理学号:2072014115006

    The Structure-basis of RIG-I and TRIM25 Interaction

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    天然免疫是机体对抗病原体的第一道屏障。在天然免疫中,RIG-I介导的RLR抗病毒信号通路能够有效的诱导I型干扰素的表达,进而诱导一系列相关的抗病毒天然免疫反应。RIG-I在识别具有5’-三磷酸帽的短RNA配体后,发生构象变化和寡聚化,进而激活线粒体和过氧化物酶体膜上的信号伴侣MAVS。该信号传导过程受到RIG-I的翻译后修饰的严格调控,包括TRIM25介导的63位赖氨酸链接的多聚泛素链的泛素化修饰。本论文旨在阐明TRIM25介导的泛素化机制。我们采用NMR方法,研究TRIM25的PRYSPRY结构域与RIG-I的CARDs结构域间的相互作用,并通过单点突变和免疫共沉淀方法对指认的作用位点加以验...Innate immunity is the body’s first line of defense against pathogens. Being part of the innate immunity, RIG-I-mediated RLR antiviral signaling pathway plays an important role in the induction of type I interferon and the subsequent series of antiviral innate immune responses. After the recognition of short RNA ligands with the 5'-triphosphate cap, RIG-I undergoes conformational changes and oligo...学位:理学硕士院系专业:生命科学学院_生物化学与分子生物学学号:2162014115256

    The Choices of China Catastrophe Insurance

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    中国是世界上自然灾害最为严重的国家之一,自然灾害造成的直接经济损失已经占到我国GDP的3%——5%,伴随着全球气候变化以及中国经济快速发展和城市化进程不断加快,自然灾害防范应对形势更加严峻,以往以政府财政拨款救助为主的事后巨灾损失补偿模式已经无法适应我国社会生活和经济发展的步伐,于是,依靠保险这一专业的风险管理手段来分散巨灾风险、弥补巨灾损失的巨灾保险制度呼之欲出。 本文以保险原理和经济学为理论基础,以国际的视角和历史的眼光,通过对世界上运作地最为成功的几类巨灾保险制度的案例进行比较分析,并借助贯穿全文的两个发生在我国的巨灾案例(即2008年初南方雨雪冰冻灾害和“5.12”汶川地震)对我国现...China is one of the countries most affected by natural disasters. The direct economic losses caused by natural disasters accounted for 3 to 5 percent of China GDP. In the wake of climate change, rapid growth of economy and acceleration of urbanization in China, the situation to prevent and respond the losses caused by natural disasters is more urgent and serious. It does not suit social and econom...学位:管理学硕士院系专业:管理学院工商管理教育中心(MBA中心)_工商管理硕士(MBA)学号:1792006115156

    对氨基苯甲酸在拟南芥根生长发育中对生长素运输的调控

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    为探究对氨基苯甲酸(PABA)影响拟南芥根部生长发育的作用机制,通过以野生型拟南芥和DR5::GUS转基因拟南芥为实验材料,研究了PABA外源处理对根系形态结构和生长素的运输和分布的影响。结果表明:200 μmol/L PABA可以明显抑制拟南芥幼苗主根生长,并促进侧根和根毛的发育。PABA可增强生长素类似物2,4-D对幼苗主根生长抑制的影响,促进根毛伸长;相反,PABA可在一定程度上恢复生长素运输抑制剂NPA对幼苗主根和根毛生长发育的抑制作用。此外,PABA可以诱导拟南芥根尖生长素的积累,并影响生长素极性运输相关基因PIN1、PIN3和AUX1的表达。综上所述,PABA可调节根部生长素运输和分布,在拟南芥根生长发育过程中起重要作用。国家自然科学基金(30571259

    对氨基苯甲酸在拟南芥根生长发育中对生长素运输的调控

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    为探究对氨基苯甲酸(PABA)影响拟南芥(Arabidopsis thaliana)根部生长发育的作用机制,以野生型和DR5∷GUS转基因拟南芥为实验材料,研究了PABA外源处理对根系形态结构和生长素运输的影响.结果表明:200μmol/L PABA可以明显抑制拟南芥幼苗主根生长并促进侧根和根毛的发育.PABA可增强生长素类似物2,4-D对幼苗主根生长的抑制作用和对根毛伸长的促进作用;相反,PABA可在一定程度上减弱生长素运输抑制剂NPA对幼苗主根和根毛生长发育的抑制作用.此外,PABA可诱导拟南芥根尖生长素的积累以及生长素极性运输相关基因PIN1、PIN3和AUX1的表达.综上所述,PABA可调节根部生长素运输和分布,在拟南芥根生长发育过程中起重要作用.国家自然科学基金(30571259

    旋毛虫病的免疫诊断研究

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    旋毛虫病的免疫诊断研究刘光明蔡海松综述宋思扬苏文金审校厦门大学生物学系(厦门361005)旋毛虫病的临床表现错综复杂,临床诊断较为困难,易与其它传染病相混淆。肌肉活检发现幼虫或囊包虽可确诊,但在轻度感染和感染早期往往不易检出,即使是感染晚期,因受摘取..

    Medium Optimization of Astaxanthin by Oceanic Red Yeast

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    为了提高海洋红酵母发酵虾青素的产量水平,对海洋红酵母的培养基成分进行了初步研究。试验结果表明,海洋红酵母能利用葡萄糖、淀粉水解糖、糖蜜等多种碳源,用淀粉水解糖为碳源培养海洋红酵母所获得的虾青素体积产率最大;用牛肉膏为氮源有利于提高海洋红酵母的生物量,以(NH4)2SO4、NH4Cl和蛋白胨为氮源有利于提高海洋红酵母的虾青素体积产率,用KNO3、草酸铵、蛋白胨、尿素有利于提高海洋红酵母的虾青素细胞产率;在海洋红酵母的培养基中添加Mn2+、Cd2+、Zn2+、Fe2+能增加生物量,添加Zn2+、Fe3+、Mn2+能增加海洋红酵母的虾青素体积产率,添加Fe3+能提高海洋红酵母的虾青素细胞产率。In order to improve the production level of astaxanthin by oceanic red yeast(ORY),the ingredients of medium for it were studied.The results of experiment showed that ORY could utilize many kinds of carbon sources such as glucose,starch hydrolyzed sugar(SHS),and molasses etc.However,volume productivity of astaxanthin was the biggest among these sugars when using SHS.Using beef extract as nitrogen source is helpful to enhance biomass of ORY, while(NH4)2SO4,NH4Cl and peptone were conducive to improve the ORY volume productivity of astaxanthin.In addition,KNO3,ammonium oxalate,peptone,and urea were conducive to improve the cellular productivity of astaxanthin.Adding Mn2+,Cd2+,Zn2+,and Fe2+ to the ORY medium,could increase the biomass.Adding Zn2+,Fe2+,and Mn2+ could increase the ORY volume productivity of astaxanthin.And adding Fe2+ could increase the ORY cellular productivity of the astaxanthin.福建省重点科技项目(2006H0033);; 厦门市科技项目(B04066

    Study on the Interaction of Gliotoxin with BSA

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    应用荧光、圆二色和紫外—可见吸收等波谱法研究胶毒素与牛血清白蛋白(bSA)的相互作用。荧光光谱实验结果表明胶毒素主要靠疏水作用与bSA结合,而对其内源荧光产生猝灭作用,其淬灭方式为静态猝灭,胶毒素与bSA的结合常数为7.2x103l/MOl。圆二色光谱检测发现,随着胶毒素浓度的增加,bSA的α-螺旋数量也增加,当胶毒素浓度为bSA浓度的100倍时,bSA的α-螺旋增加40.1%,表明胶毒素与bSA的结合改变了bSA的空间构象。The interaction between Gliotoxin and bovine serum albumin (BSA) was studied by the fluo-rescence, Circular Dichroism (CD) and ultraviolet visible (UV-Vis) techniques.The fluorescent experiment showed that the intrinsic fluorescence of BSA was quenched by the binding of gliotoxin in a static quenching procedure, with an association constant of 7.2×103 L/mol and in hydropobic forces.And the CD spectrum revealed that gliotoxin effected the conformation of BSA by increased the mass of α-helix.国家863计划项目(No.2006AA09Z410

    PURIFICATION of P49 ANTIGEN GENE PRODUCT of TRICHINELLA SPIRALLS EXPRESSED IN ESCHERICHIA COLI

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    目的建立旋毛虫P49抗原基因原校表达产物的纯化方法。方法菌体经冻融、超声破菌及提取包涵体后,用离子交换和凝胶过滤层析纯化蛋白质。结果纯化后的融合蛋白P49/gST经SdS-PAgE电冰鉴定达电泳纯。双抗体夹心ElISA法检测结果表明纯化的P49/gST融合蛋白能与旋毛虫感染的鼠血清和纯化融合蛋白免疫的兔血清反应,而不与正常民和兔血清反应。结论纯化后的融合蛋白P49/gST具有较高的纯度及较强的免疫活性,可望作为旅毛虫病的免疫诊断抗原。Aim To establish a purification procedure for p49 antigen gene product of Trichinella spiralis expressed inEschedchia coli.Methods After centrifugation of the bacterial culture, the bacterial pellet was resuspended and lysed byfreezing-thawing treatment and ultrasonication.Ion exchanged and gel filtration chromatography were used to purify the fu-sion protein p49/GST from the inclusion bodies- Re8ultS The purity of the fusion protein p49/GST was verified using SDS-PAGE.The purified p49/GST protein could react with mouse antisera against Tricinella sPiralis and rabbit antisera againstpurified p49/GST protein, but not with normal mouse and rabbit sera by sandwich EL1SA.Concluslon The purified fusionprotein p49/GST with high purity and good immune activity could be used for the immune aasay of trichinellosis.福建省重点(农医)项目!95-Z-15

    胰岛素降低海马谷氨酸和D-丝氨酸含量改善糖尿病大鼠空间学习记忆能力

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    目的观察胰岛素对糖尿病(DM)大鼠空间学习记忆及海马组织中谷氨酸和D-丝氨酸含量的影响。方法采用尾静脉注射链脲佐菌素(STZ)制备大鼠DM模型。注射STZ第3天建模成功后,大鼠sc给予胰岛素2 U·kg-1,每天1次,持续82 d。定期检测各组大鼠体质量及空腹血糖。第81天进行Morris水迷宫实验,检测大鼠学习记忆能力;实验结束后取海马组织,观察形态变化,并测定谷氨酸和D-丝氨酸含量。结果与正常对照组比较,DM模型组大鼠体质量明显减轻(P<0.01),血糖明显升高(P<0.01),逃避潜伏期明显延长,原平台象限游泳时间显著减少(P<0.01),海马组织中谷氨酸及D-丝氨酸的含量均显著升高(P<0.01)。胰岛素治疗组体质量增加,血糖含量恢复到正常水平。与DM模型组相比,胰岛素治疗组大鼠逃避潜伏期显著缩短(P<0.01),原平台象限游泳时间占总时间百分比显著增加(P<0.01);海马组织中谷氨酸和D-丝氨酸的含量也分别由DM模型组的(1.550±0.054)和(0.084±0.05)mg·g-1下降为胰岛素治疗组的(1.137±0.023)和(0.068±0.004)mg·g-1。结论胰岛素可以改善糖尿病大鼠空间学习记忆能力,这可能与其降低海马组织中谷氨酸和D-丝氨酸含量有关
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