Study on the Inhibitory Effects to Tyrosinase and Bioactivity by Aromatic Fragrance

酪氨酸酶（EC.1.14.18.1）是一种含铜的氧化还原酶，它具有单酚酶活性和二酚酶活性，是生物体合成黑色素的限速酶[1-3]，广泛存在于微生物、动植物及人体中。其抑制剂可广泛应用于美白化妆品、果蔬保鲜、杀虫等方面。 本论文围绕三大部分进行，第一部分是探讨蘑菇酪氨酸酶的抑制剂对单酚酶和二酚酶催化反应的抑制机理。研究了芳香族香料对蘑菇酪氨酸单酚酶和二酚酶效应，研究它们的抑制机理，并测定它们的抑制类型和抑制常数。第二部分以小鼠B16黑色素瘤细胞为研究对象，研究了芳香族香料对细胞增殖率、体内酪氨酸酶活力和对细胞黑色素生成的影响。第三部分是以大肠杆菌、枯草芽胞杆菌、金黄色葡萄球菌、串珠镰刀杆菌、茄形...Tyrosinase (EC 1.14.18.1) is a kind of redoxidase containing copper, which is of the activity of monophenolase and diphenolase.It is a key enzyme during the melanin biosynthesis and widely distributed in nature. Its inhibitors can be used widely in many fields including whitening agents, keeping fruits and vegetables fresh, insecticides. In this paper, it mainly is of three parts. The first part ...学位：理学硕士院系专业：生命科学学院生物学系_生物化学与分子生物学学号：K20014502

Progresses in the structure and biological function of Raf kinase inhibitory protein

rAf激酶抑制蛋白(rAf kInASE InHIbITOry PrOTEIn,rkIP)属于磷脂酰乙醇胺结合蛋白(PHOSPHATIdy-lETHAnOlAMInE bIndIng PrOTEIn,PEbP)家族,参与多种生理过程,可以交叉调控MAPk(MITOgEn-ACTIVATEdPrOTEIn kInASE)通路、gPCr(g-PrOTEIn-COuPlEd rECEPTOr)通路和nf-κb(nuClEAr fACTOr-κb)信号通路。细胞信号转导通路的异常会促进肿瘤的发生与发展。rkIP在肿瘤发生、发展中发挥着重要作用,影响肿瘤细胞的转移和治疗,是一种新的肿瘤诊断标志物。开展rkIP的结构生物学研究有助于理解rkIP发挥生理功能的结构基础,对揭示人类重大疾病(肿瘤)的分子机制以及研发用于细胞信号转导异常相关疾病的药物,都有着极其重要的科学意义。主要阐述了rkIP的结构特点、生物学功能及其与肿瘤疾病的关系。Raf kinase inhibitory protein(RKIP) is a member of the phosphatidylethanolamine-binding protein(PEBP) superfamily,which plays vital roles in many physiological processes and regulates MAPK,GPCR and NFκB signaling pathways.Abnormal signaling pathways will promote tumorigenesis and development.It has been reported that RKIP modulates tumors at several stages including tumorigenesis,development,metastasis and therapeutic response.By now RKIP has been considered as a new biomarker for cancer diagnosis.Therefore,it is highly significant to study the structure and function of RKIP,which helps us understand the structural basis and the molecular mechanism of RKIP-modulated signal pathways,and facilitate the drug development against diseases caused by abnormal signal transduction.This article reviewed the structural characteristics,biological functions of RKIP and its relationship with tumor.国家自然科学基金项目(30900233

对氰基苯酚对蘑菇酪氨酸酶的抑制作用

报道了对氰基苯酚对蘑菇酪氨酸酶单酚酶和二酚酶活力的抑制效应.结果表明,对氰基苯酚对酪氨酸酶活性的抑制作用表现为可逆抑制作用,对酪氨酸酶的单酚酶的效应主要表现于迟滞时间有明显的延长,对稳态酶活力有显著抑制作用.0.50mmol/L对氰基苯酚使得单酚酶的迟滞时间从18s延长到80s,增大4.4倍,稳态酶活力下降80%.对氰基苯酚对二酚酶的抑制作用显示浓度关系,测定导致酶活力下降50%的抑制剂浓度(IC50)为0.80mmol/L,其抑制作用为竞争性类型,抑制常数KI为0.31mmol/L.通过研究对氰基苯酚对酪氨酸酶的抑制作用机理,试图寻找新型的有增白作用的化妆品添加剂

modeling and rendering snowy natural scenery

合成高度复杂自然场景一直是计算机图形学中的一个富有挑战性的课题.生成雪景或许更加困难,因为利用常用的造型工具,比如多边形和曲面来表达雪的形状非常不方便.该文介绍一种解决这个问题的方法,这种方法采用位移映射(displacement mapping)来构造近处由多边形构造的物体上的雪块,而体纹理映射(volumetric texture mapping)被用来处理远处的复杂物体,比如树木.绘制结果显示,这种方法能够在较少的内存和计算开销的基础上绘制出高度复杂和真实的雪景