202 research outputs found

    制油方法和精炼过程对麻疯籽油品质的影响

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    为更好地了解油脂加工过程对麻疯籽油品质的影响,对比研究了浸出和压榨2种制油方法对麻疯籽油理化指标、脂肪酸组成的影响,并研究了浸出麻疯籽油在精炼过程中的品质变化。结果表明:2种制油方法制备的麻疯籽油在理化指标上存在较大差异,但在脂肪酸组成上并没有显著差异;与压榨法相比,浸出法制备的麻疯籽油具有较高的酸值、碘值、过氧化值、皂化值以及磷脂含量;麻疯籽油中的主要甘三酯为LOO(17.86%),LLO(16.02%),POL(14.06%),POO(7.14%),LLP(6.58%),OOO(6.44%),St OL(6.38%);此外,精炼对麻疯籽油的主要脂肪酸组成基本没有影响,但精炼后麻疯籽油的酸值、过氧化值、碘值和皂化值均明显降低

    人CD4胞外区蛋白在杆状病毒-昆虫细胞系统中的表达纯化及性质鉴定

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    目的:通过条件优化实现人CD4蛋白胞外区在杆状病毒-昆虫细胞表达系统中的高效表达,并对纯化获得的人CD4蛋白胞外区进行抗原性与免疫原性分析。方法:通过选择人CD4分子胞外片段构建重组杆状病毒(p Ac-CD4),然后感染昆虫细胞进行蛋白的表达,采用镍离子亲和层析纯化。运用SDS-PAGE、Western blot、体积排阻色谱、ELISA、SPR法等分析纯化得到目的蛋白的理化性质和抗原性。通过弗氏佐剂与目的蛋白混合免疫BALB/c小鼠,监测小鼠免疫血清的抗体生成。结果:经纯化可获得纯度90%以上的人CD4蛋白,每升细胞培养液最终可获得11.2 mg的目的蛋白,且该人CD4胞外区蛋白具有良好的抗原性。小鼠血清监测结果显示人CD4蛋白能有效刺激机体产生免疫应答,显示其具有良好的免疫原性。结论:本研究通过杆状病毒-昆虫细胞系统进行高效表达,获得抗原性和免疫原性良好的人CD4胞外区蛋白,为HIV受体和感染的研究奠定基础。国家自然科学基金(No.81671645

    脱氢姜酮对人肺癌细胞A549细胞毒活性的研究

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    对生姜中有效成分脱氢姜酮对人肺癌细胞A549细胞(简称A549细胞)毒活性进行研究,同时考察其氢化产物姜酮的细胞毒活性,研究其构效关系.实验利用MTT法测定脱氢姜酮和姜酮对A549细胞的生长抑制作用,DNA电泳研究脱氢姜酮和姜酮对DNA切割作用,免疫印迹实验检测相关蛋白的表达.实验结果表明:脱氢姜酮对A549细胞增殖具有一定的抑制作用,在40~300μmol/L之间呈剂量依赖性;脱氢姜酮抑制A549细胞增殖的能力和对DNA的切割能力大于姜酮;N-乙酰基-L-半胱氨酸(NAC)明显抑制脱氢姜酮的活性,对姜酮没有影响.免疫印迹结果显示脱氢姜酮可诱导CHOP蛋白的表达,表明脱氢姜酮通过内质网应急途径发挥作用

    Surface structure-controlled synthesis of nanocrystals through supersaturation dependent growth strategy

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    纳米晶体很多重要的物理化学性质与其表面结构密切相关, 纳米晶的表面结构调控及相关理论研究是前沿和热点领域.; 本评述总结了非平衡态过饱和条件下纳米晶体生长热力学相关理论及其在离子晶体、分子晶体、贵金属、氧化物、金属有机框架等5类纳米晶体表面结构控制中的应; 用. 从热力学推导出的"类"Thomson-Gibbs方程可以发现, 晶体裸露晶面的表面能与其生长过程生长基元的过饱和度成正比.; 该理论揭示了过饱和度在纳米晶体表面结构控制中的重要作用, 为合理设计合成具有特定表面结构的纳米晶提供了有效指导.Many physical and chemical properties of nanocrystals are closely; related to their surface structures. Studies on the surface structure; control of nanocrystals and related theories are hot and frontier; research topics recently. In this review, we introduce the; supersaturation control strategy and its application in the surface; structure control of nanocrystals ranging from ionic, molecular,; metallic, metal oxide, to metal-organic frameworks crystals. Deduced; from thermodynamics, it can be found that the surface energy of; nanocrystals is directly proportional to the supersaturation of growth; units. The relationship between supersaturation and surface energy; provides an important theoretical basis for the controlled synthesis of; nanocrystals with specific surface structure.国家重点基础研究发展计划; 国家自然科学基金项目; 中央高校基本科研业务费专项资金资助; 中国博士后科学基

    Role of Nrf2/ARE in chemoprevention of cancer

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    化学致癌过程是涉及启动、促进和进展等多阶段的复杂过程。癌症的化学预防是应用天然的或合成的化学物质,以阻断、抑制或其癌变过程,从而达到预防肿瘤的目的。化学致癌物的体内生物转化依靠肝脏的Ⅰ相和Ⅱ相代谢相酶来完成。作为对化学预防剂的应答反应,碱性亮氨酸拉链蛋白家族成员转录因子Nrf2首先从胞质蛋白Keap1上解离,然后发生核内转位,与Ⅱ相代谢酶基因上游的抗氧化反应元件结合诱导Ⅱ相代谢酶基因的表达,这是化学防癌的重要机制;Nrf2/ARE对Ⅱ相代谢酶的调节涉及PI3K、MAPK、PKC等细胞内重要信号传导途径。这些发现加深了化学防癌机制的认识并为评估潜在抗癌物质提供了新的策略。 【英文摘要】 Chemical carcinogenesis is involved in complicated multiple stages of initiation,promotion and progression.Chemoprevention comprises multiple intervention methods using either pharmacological or dietary agents to impede,arrest,or reverse carcinogenesis at various stages.Biotransformation of carcinogens may be associated with hepatic phase Ⅰ and Ⅱ detoxifying enzymes.It is proved that Nrf2,a member of the basic-leucine zipper family of transcription factors,is dissociated from cytoplasmic protein Keap1 first..

    平潭实验区行政主体资格与管理权能的界定

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    注重制度建设,尤其是法律制度建制,是各种实验区、示范区走向成功的极为重要的条件,也是当前平潭实验区急切的现实需求。平潭实验区面临着行政主体定位不科学、行政管理权限范围模糊、行政管理授权不明等体制局限。平潭实验区的体制创新首先是法律创新问题,只有完善关于平潭实验区的立法,赋予实验区独立行政主体地位,创新有关经济、社会、行政管理等领域的体制机制,走向法治政府,才能使平潭真正发挥两岸交流合作中的“综合实验“作用,实现国家赋予它的历史使命,成为探索两岸交流合作新模式的先行区。厦门大学“985工程”-公共管理重点学科建设项目; 平潭综合实验区行政体制改革方案研究(平潭综合实验区管委会委托项目

    虎伯寮南亚热带雨林自然保护区的竹类资源及开发利用

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    福建省南靖县虎伯寮南亚热带雨林自然保护区的竹类资源丰富 ,有 8属 2 0种 3变种 5栽培型 ,其中梅花毛竹 ( Phyllostachys heterocycla cv.obtusangula)为福建竹类新分布 ;主要的竹林类型有毛竹林、麻竹林、绿竹林、石竹林、单竹林。竹类资源的开发利用具有广阔的前

    Intratumoral Chemotherapy with an Implantable Collagen Film Impregnated with Epirubicin-loaded Polylactic Acid Microspheres Inhibits Tumor Growth in Hepatocellular Carcinoma Xenografts

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    [中文文摘]制备用于实体肿瘤局部治疗的植入型表阿霉素缓释药膜。采用复乳-溶剂挥发法制备聚乳酸载表阿霉素缓释微球,用交联复合法制备含载药微球的植入型胶原药膜;用扫描、透射电镜、共聚焦及粒度仪等考察微球和药膜的形貌、结构、粒径及体外释放;用H22肝癌荷瘤动物模型评价其体内抑瘤效果。结果:载药微球粒径分布均匀,外观圆整,平均粒径为5.81μm;微球的载药量4.39%,包裹率为37.2%;10h内载药微球在模拟体液中的累积释放率为35%;腹腔注射载药微球与瘤体局部植入胶原药膜对H22肝癌均有明显的抑瘤效果;微球注射与药膜植入两种不同给药方式对H22肝癌抑瘤效果也存在显著性差异(P<0.05)。植入型载表阿霉素缓释胶原膜具有良好的药物局部缓释特性,在肿瘤的术后局部治疗方面具有良好的临床应用前景。[英文文摘]Drug-releasing implants delivering chemotherapeutic agents can provide promising local therapy to patients with malignant disorders.The purpose of the present study was to develop implantable collagen film impregnated with epirubicin-loaded polylactic acid(PLA) microspheres(EPI-PM) for intratumoral administration in solid tumors.EPI-PM was prepared by double emulsion-solvent evaporation method,and the microspheres were further incorporated in biodegradable chemically cross-linked collagen to formulate implantable collagen film. The microspheres were characterized by scanning electron microscope , transmission electron microscope and laser confocus microscopy. In vitro release of epirubicin was examined by ultraviolet spectrophotometry. Transplantable murine hepatoma 22 (H22) model was used to evaluate the effects of EPI-PMor collagen film impregnated with EPI-PMon murine liver cancer.The results indicated that the epirubicin was well incorporated and dispersed homogeneously in PLA. The EPI-PM was uniformly spherical with average diameter of 5181μm, drug loading of 4139% , and embedding ratio of 3712%. The cumulative drug release rate of EPI2PM was 35 % in analog body fluid at the 10h. The tumor growth rate was significantly inhibited by intraperitonal injection of EPI2PMor intratumoral implantation of collagen film impregnated.国家重大科学研究计划项目(2006CB933300); 福建省自然科学基金(C0610045); 厦门市科技计划项目(3502Z20055007); 厦门市科技创新资金项目(3502Z20041029)

    Studies on Light-Scattering Nephelometic Determination of Sulfate Radical with Polyvinyl Alcohol-Barium Sulphate System

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    对聚乙烯醇—硫酸钡乳浊体系的共振光散射光谱、二级光散射光谱与反二级光散射光谱的光谱特性进行研究, 并开展了用此体系测定环境水样中硫酸根的应用研究, 3 种散射光谱法在0 ~0-24Mg/Ml的硫酸根浓度范围内的标准曲线均呈良好线性关系.The spectra of resonance light scattering(RLS),double scattering(DS) and anti-double scattering(ADS) for polyvinyl alcohol-barium sulphate system have been studied by using an ordinary spectrofluorophotometer.RLS,DS and ADS have been applied to the determination of sulfate radical in environmental water sample.The results are satisfactory

    Antitumor effects of a novel chloroquinoline derivative as EGFR inhibitor on human esophageal carcinoma

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    目的:评价Egfr抑制剂4-取代-7氯喹啉衍生物(TW9183)的体内外抗肿瘤生物活性。方法:采用分子对接技术探讨其与Egfr之间的相互作用模式,蛋白免疫印迹法评价在蛋白水平的直接作用,体外细胞生物学及体内裸鼠移植瘤模型探讨TW9183的活性。结果:Egfr受体的氨基酸残基MET769,PrO770,lyS721可与TW9183间形成氢键,蛋白印免疫迹法表明化合物抑制Egfr的磷酸化;体外细胞实验显示TW9183有明显抑制食管癌细胞增殖、周期阻滞于g2/M期及促进凋亡的效果;裸鼠食管癌移植瘤模型验证其在体内同样具有抑制肿瘤生长促进凋亡的作用。结论:TW9183在体内外实验中显示具有潜在的抗食管癌作用。Objective: To explore the underlying mechanism of 4-substituent-7-chloroquinoline derivative(TW9183),which has a selective anti-tumor effect in vitro and in vivo.Methods: Docking simulation was performed to position compounds into the EGFR structure active site to determine a possible binding model.We also used Western blot assay to directly evaluate the interaction.Cell cultures and tumor xenografts were utilized to test the effect of TW9183.Results: TW9183 was nice bound to the EGFR with the amino hydrogens of MET769, PRO770 and LYS721,forming optimal H-bonds interaction.Western blot assay showed that the compound inhibited EGFR phosphorylation.TW9183 treatment increased typical apoptosis and the number of cells in the G2/ M phase in ECA-109 cells.In ECA-109 xenograft model in nude mice,TW9183 inhibited tumor growth and promoted apoptosis.Conclusion: TW9183 has potential antitumor activity in vitro and in vivo.泉州市科技计划重点项目(2013Z35
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