2,809 research outputs found
Flow Cytometric Sorting Based Molecular Ecological Study of Prochlorococcus in the South China Sea
海洋原绿球藻(Prochlorococcus)是贫营养大洋的优势自养微型生物,可划分为光生理以及16SrRNA基因系统发育显著差异的两个基本生态型,即高光生态型(Highlightecotype,HL)和低光生态型(Lowlightecotype,LL)。在高光生态型内部有两个不同的亚类,低光生态型有四个亚类,但近年来研究发现还存在着未知的亚类,所以寻找未知亚类是改善原绿球藻定量研究以及加深了解其环境适应机制的必要途径。 流式细胞仪是研究超微型生物的重要工具,本论文与传统的膜过滤采样方法不同,利用流式细胞仪的分选功能获得原绿球藻浓缩样品,并采用简洁的冻融法提取DNA,通过克隆文库以及变性梯度...Prochlorococcus is the most abundant photosynthetic organism in the oligotrophic ocean. It can be divided into two basical ecotypes with distinct photophysiology and phylogenetically distinct 16S rRNA markers, the high light (HL) and low light (LL) ecotypes. Two ecologically distinct subclusters have been identified within the HL ecotype and at least four distinct genotypes within the LL. Recently...学位:理学硕士院系专业:海洋与环境学院_环境科学学号:2005130222
Study on the formation mechanism of gelation of konjac glucomannan
利用直流电,在添加CaCl2、MgCl2、FeCl3、钨酸钠的条件下,分别制备了KGM-Ca、KGM-Mg、KGM-Fe、KGM-T凝胶,对获得凝胶后电处理KGM溶胶电极两侧pH进行了测试,并对KGM-T凝胶进行了FTIR、Raman、SEM、XRD、DSC表征。结果表明,正极附近KGM溶胶为酸性,负极一侧KGM溶胶为碱性。SEM表明KGM在粉末状态下,外表呈现规则的微纤维状,KGM分子间有氢键;KGM溶胶冻干后呈现大小孔洞不均匀的支架结构,直流电处理的KGM溶胶冻干后的扫描电镜没有发生明显的变化,电处理未使KGM链的糖苷键发生断裂;KGM-Ca凝胶的表面形貌呈现大小孔洞不规则的絮状结构,KG...Konjac glucomannan (KGM) -Ca 、KGM-Mg 、KGM-Fe 、KGM-tungsten (KGM-T) gels were successfully produced under DC electric fields in the presence ofCaCl2、MgCl2、FeCl3 and sodium tungstate. pH experiments were conducted tomeasure pH value of DC treated KGM sol. And KGM-T gels were characterized byFTIR、Raman、SEM、XRD and DSC. pH experiments showed that KGM solcontaining Na2WO4.2H2O in the vicinity of the p...学位:博士后院系专业:材料学院_软物质与功能材料学号:201317006
Network Business Marketing Strategy Research of HXB
摘要 随着现代信息化技术的高速发展,民众的传统生活方式发生了重大转变,进而对于传统行业的营销手段以及方式也提出了新的要求以及挑战。就我国商业银行为例,在信息化高速发展的今天,通过网络业务的方式开设,我国商业银行能够有效的降低在客户服务过程中的运营成本,如何有效的通过网络业务的开展,强化商业银行市场竞争力以及服务质量、效率的提升成为了制约当代商业银行网络业务发展的关键。 网络业务营销是今后商业银行的重要营销方式,同时也是今后商业银行竞争的重要战略市场体现,在优化自身网络业务营销策略推行的过程中,商业银行必须优化以网络业务营销基础平台为依托,同时结合现代客户的需求转变点为基础,通过针对化的...Abstract With the rapid development of modern information technology, people's traditional way of life has changed greatly, and it also puts forward new requirements and challenges for the traditional industry marketing tools and methods. As an example, in the development of information technology, the commercial banks can effectively reduce the operating costs in the process of customer service....学位:工商管理硕士院系专业:管理学院_工商管理硕士(高级管理人员工商管理硕士)学号:X201315619
Functions of DHP and its nuclear receptor on reproductive neuroendocrine in zebrafish (Danio rerio)
本文研究了DHP对野生型和孕酮核受体敲除纯合型两种类型雄性斑马鱼垂体中促性腺激素β亚基基因(fshb和lhb)、脑中多巴胺合成限速酶酪氨酸羟基化酶基因(th2)及多巴胺二型受体基因(drd2a和drd2b)和促性腺激素释放激素基因(gnrh2和gnrh3)mRNA表达的影响。主要研究结果如下: 1.野生型雄性斑马鱼垂体中促性腺激素β亚基基因(fshb和lhb)mRNA表达呈现周日变化趋势,可分为基础表达期、上升表达期和高峰表达期3个期,高峰表达期的mRNA表达量显著高于其它2个期。野生型雄性斑马鱼活体暴露于DHP水溶液后,垂体中fshb和lhbmRNA表达量随DHP暴露浓度的增加和暴露时间的...We examined the effects of DHP on the fshb, lhb, th2, drd2a, drd2b, gnrh2 and gnrh3 mRNA expression in WT and pgr-/-. The main results were as follows: 1. fshb and lhb mRNA expression of WT showed diurnal change. The level of peak expression phase was significantly higher than those of other two expression phases. After WT were exposed to DHP in vivo, fshb and lhb mRNA expression showed a upward ...学位:理学博士院系专业:海洋与地球学院_海洋生物学学号:2232012015345
Studies on the regulation of membrane microdomains (lipid rafts) / Flot to mitogen-activated protein kinase signaling pathway and its effect on reversing multidrug resistance of hepatocellular carcinoma cells
目的: 1.构建耐药肝癌细胞模型。 2.检测Flot下调对ERK1/2信号通路的影响,明确能否通过Flot调控ERK1/2信号通路从而实现肝癌细胞耐药性的逆转。 3.检测脂筏破坏剂甲基-β-环糊精破坏脂筏结构对ERK1/2的影响,探索脂筏与ERK1/2之间的关联。 4.检测下调Flot对耐药肝癌细胞侵袭能力的影响。 5.构建过表达质粒Flot1/pcDNA3.1(+)、Flot2/pcDNA3.1(+),为后续研究工作奠定基础。 方法: 1.用阿霉素大剂量冲击法诱导细胞,Celltiter-Glo荧光细胞活性检测法检测细胞对阿霉素的敏感性。 2.设计siRNA和shRNA,Re...Objective: 1. To induce poly multidrug resistant (MDR) cell models from human hepatocellular carcinoma (HCC) cell lines by chemotherapy drugs and detect resistance of the developed HCC MDR cells. 2. To detect the effects of ERK1/2 pathway by down-regulating Flot on HCC drug-resistant cells, thus to explore if down-regulating Flot could affect ERK1/2 pathway and reverse resistance of HCC MDR cell...学位:医学硕士院系专业:医学院_病理学与病理生理学学号:2452012115310
Study on Embryotoxicity and Bioaccumulation of the Combined Exposure of Typical Antibiotics in Oryzias Melastigma Embryos
抗生素以其优良的抗菌作用,被人类广泛地使用,致使其以各种途径,大量地进入到自然环境中,尤其是水环境中。其中,磺胺类和氟喹诺酮类药物因其广谱的抗菌性而被大量使用,因此成为水环境中检出率最高、检出浓度最大的两类抗生素。目前,环境中抗生素的研究主要集中于痕量检测,对于水生生物毒性研究多针对于大型溞、浮萍、月芽藻等低等水生生物,而对低剂量、长期暴露下抗生素对鱼类的生理毒性效应,及其在生物体内的富集研究相对较少,其在水环境中潜在的生态毒理效应尚未有明确的评价,有必要对相关的生态毒理数据进行完善,同时,研究手段上偏重生物学方法,与化学相结合来研究毒性作用机制非常欠缺。 本研究从磺胺类和氟喹诺酮两大类抗生...Antibiotics have been widely used by people with its excellent antibacterial effect, which result in a large number of antibiotics into the environment through a variety of ways, especially water environment. The sulfonamides and fluoroquinolones were widely used, and this has caused that they became one of the highest detection rate and quantity antibiotics. Currently, most reseach focus on trace...学位:理学硕士院系专业:海洋与地球学院_海洋化学学号:2232012115130
Exploration on Social Assistance to the Poor Elderly in Fuzhou
社会救助作为伴随社会发展而出现的一项社会保障制度,对于缓解老年贫困,提高老年人的福祉具有重要意义。贫困老年群体因其收入低、健康状况差而被低保、医疗救助、特殊困难群体救助等多项救助制度覆盖。在我国社会经济发展进步的过程中,老年社会救助制度也逐渐系统化、科学化。然而我国老年社会救助还存在救助水平不高,救助内容偏少,救助覆盖范围比较窄等问题。 不论是对于建立和完善具有中国特色的老年社会救助制度,还是为经济发展提供一个稳定的社会环境,对贫困老年社会救助这项制度的研究都具有重要意义。本文以福州为个案,通过实证分析,试图对福州市“十二五”期间贫困老年社会救助情况进行梳理与深入分析,在此基础上提出完善贫困...Social assistance,as one of the social security system accompanied with the development of society, is of great significance to alleviate poverty and improve the welfare of the elderly. The poor elderly population, due to their low income and poor health,is well protected by the subsistence allowance, medical assistance and special relief and other relief system. With the improvement of China's so...学位:公共管理硕士院系专业:公共事务学院_公共管理硕士学号:1392011115043
TGF-β1-induces activation of HSC-T6 and epithelial-mesenchymal transition in rats
目的:研究转化生长因子-β1(TGF-β1)在大鼠肝星状细胞-T6细胞系(HSC-T6)活化及上皮间质转化(EMT)中的作用及其对TGF-β1/Smads信号通路的影响,揭示肝纤维化的发生与发展的分子病理机制,为肝纤维化的逆转治疗及肝硬化的防治提供新靶点。 方法:体外培养大鼠肝星状细胞-T6细胞系,用四甲基偶氮唑盐(MTT)法筛选TGF-β1对肝星状细胞-T6细胞系的最适作用浓度;用MTT法筛选出的最适作用浓度(10μg/L)的TGF-β1处理肝星状细胞24小时,倒置相差显微镜下观察细胞形态学的改变,免疫荧光染色法检测细胞内纤维形肌动蛋白(fibrousactin,F-actin)的表达,R...Objective: To observe the effect of TGF-β1 on activation and epithelial-mesenchymal transition, to investigate the effects of TGF-β1 on TGF-β1/Smads signaling pathway in rat hepatic stellate cells-T6,reveal the pathogenesis of hepatic fibrosis, and provide new target for the treatment of hepatic fibrosis and liver circosis. Methods: Adopt the MTT method to screening the optimum working concentra...学位:医学硕士院系专业:医学院_内科学学号:2452014115350
Theoretical studies of magnetic resonance shielding constants
核磁共振(NMR:Nuclearmagneticresonance)技术已经发展成为结构解析的标准技术。核磁共振屏蔽常数的理论计算是预测核磁共振波谱常数必不可缺少的工具。而且,其技术和方法都向着生物大分子的方向发展。 近几年里,越来越多的组合方法被运用到核磁共振屏蔽常数的理论计算中。其中焦点分析(FPA-M:Focalpointanalysisformagneticproperties)方法已经成功地计算了各类小分子体系的屏蔽常数,并且其精度达到了CCSD(T)完全基组(CBS:CompleteBasisset)极限值的水平。然而,FPA-M方法需要同时计算MP2/cc-pV5Z和CCSD(...Nuclear magnetic resonance (NMR) is so important that it has become a standard technique for giving key information about the structure and composition. The theoretical calculation of NMR parameters is a necessary tool for the prediction of NMR spectroscopy. Moreover, the methods and technology continue to develop to enlarge the limit for size of molecules. In recent years, more and more combinat...学位:理学硕士院系专业:化学化工学院_物理化学学号:2052014115159
Mechanistic study of IG20/MADD in regulating glucose-induced insulin release in pancreatic B-cells
糖尿病已经成为影响我国居民健康的重大疾病。前期研究中实验室已经通过胰腺B细胞特异性IG20/MADD基因敲除小鼠发现该基因的敲除可导致B细胞对葡萄糖刺激的胰岛素分泌缺陷,进而导致小鼠2型糖尿病表型的产生,表明IG20/MADD基因在调节胰岛细胞功能,尤其是胰腺B细胞内葡萄糖诱导的胰岛素分泌过程起着关键作用,也是该类2型糖尿病患者致病的关键基因。 本课题的主要研究内容就是进一步对IG20/MADD参与胰腺B细胞胰岛素分泌过程的分子机制进行深入研究。一方面,我构建了一系列人KIAA0358这一IG20/MADD基因剪接异构体的不同标签融合表达质粒,并最终利用腺病毒表达系统在Min6细胞系上实现了...Pancreatic β-cell dysfunction is a common feature of type 2 diabetes. Earlier, we had generated IG20/MADD conditional knockout (KMA1ko) mice. Deletion of IG20/MADD in β-cells resulted in hyperglycemia and glucose intolerance associated with reduced and delayed glucoseinduced insulin production. These findings indicated that IG20/MADD plays a critical role in glucose-induced insulin release from β-...学位:博士后院系专业:化学化工学院_药理学学号:201419001
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