194 research outputs found

    Research on the Certified Public Accountant Environmental Auditing

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    当前,环境污染和生态破坏已经成为影响我国战略发展的重要因素。我国的环境保护工作是由国家环保部门和国家审计机关联合开展的,国家环保部门的工作侧重于事前审批和控制,国家审计机关则侧重于事后跟踪与监督。为了监督国家环保资金的投入和使用情况,监督环境法规的遵守情况,1998年国家审计署设立了农业与资源环保司。该部门主要负责审计政府部门的资源能源、环境保护资金项目,开展专项审计调查等工作。到目前为止,环境审计的实施主体只有国家审计机关,其审计能力因受制于人员数量等因素而显得相对有限。而我国目前对企业负有主要审计责任的是注册会计师,他们规模庞大,相对国家审计而言人员充沛。但是可惜的是,注册会计师对环境事项...Environmental pollution and ecological damage have become important factors influencing the development of China. In China, the work of environmental protection is developed by related national environment department and the auditing agency. The former focuses on beforehand approval and control, while the latter focuses on post tracking and supervision. In order to supervise the use of the funds p...学位:管理学硕士院系专业:管理学院会计系_会计学学号:1752007115108

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    目的:为借助分子影像技术提高抗肿瘤药物研发效率、降低研发成本提供参考。方法:以“分子影像技术”“药物研发”“肿瘤诊断”“生物标志物”等为关键词,通过检索和筛选中国知网、中国国家图书馆、PubMed、WebofScience等数据库收录的2017年4月以前发表的分子影像技术用于抗肿瘤药物研发的最新文献,进行整理、归纳和综述。结果与结论:近年来分子影像技术已取得重大进展,正越来越广泛地应用于抗肿瘤药物研发,并在药物生物分布标志物(药物由血液循环运送到体内各脏器的过程)、药效学生物标志物(药物对机体的作用及作用机制)、疾病生物标志物(用于疾病诊断、判断疾病分期或者用来评价新药或新疗法在目标人群中的安全性及有效性)及患者选择生物标志物(识别可能对治疗有反应的患者,指导治疗)等方面发挥重要作用。分子影像技术的成功应用,有望提高抗肿瘤药物开发全链条的效率和收益,其潜在价值有待进一步开发。国家科技部重点专项项目(No.2017YFA0205200):国家自然科学基金资助项目(No.81101101、81422023、51273165、U1505221);教育部科技重点项目(No.212149);教育部新世纪优秀人才支持计划(No.NCET-13-0502

    纳米酶在疾病治疗中的最新进展

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    纳米酶是具有酶催化活性的纳米材料,对比天然酶,纳米酶具有价格便宜、制备工艺简单、稳定性好、循环利用率高等优势.早期的纳米酶研究主要集中在检测方面,包括检测离子、小分子、核酸、蛋白质、癌细胞等,随着对纳米酶的深入了解,研究人员发现纳米酶在疾病治疗领域也具有巨大的应用前景.本论文将介绍纳米酶在细菌感染、炎症、癌症、神经退行性疾病等治疗领域的最新研究进展

    On the Minimum Roots of the Adjoint Polynomials of Unicyclic Graphs

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    引入伴随多项式是为了从补图的角度研究色多形式,图的伴随多项式的极小根可用于判定色等价图.β(g)表示图g的伴随多项式的极小根.n表示n个顶点的单圈图的集合.分别确定了具有MAX{β(g)|g∈Ωn}和MIn{β(g)|g∈Ωn}的所有单圈图.The adjoint polynomial was introduced for solving the chromaticity problem of the complements of graphs.The minimum roots of the adjoint polynomials of graphs can be applied to sort out graphs that are not chromatically equivalent.Let β(G) be the minimum root of the adjoint polynomial of the graph G.Denote by n the set of all unicyclic graphs on n vertices.All graphs with max{β(G)|G ∈Ωn}(resp.min{β(G)|G ∈Ωn}) are determined.supportedbyNSFC(11061027;11161037); theNaturalScienceFoundationofQinghaiProvince(2011-Z-907;2011-Z-911

    Preparation and Characterization of Clean and Uniform Substrates for Surface-Enhanced Raman Spectroscopy

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    作者简介: 任斌, 男, 博士, 教授, 博士生导师, 主要从事光谱电化学研究. E-mail : [email protected][中文文摘]采用盐酸羟胺种子生长法制备60 nm左右的粒径均一的金纳米粒子,通过在ITO上修饰3-氨基丙基-三甲氧基硅烷(APTMS)对金纳米粒子进行组装,得到组装密度较高、均一的表面增强拉曼光谱(SERS)基底;采用等离子体清洗再用醋酸溶液浸泡除去氧化层的方法,可获得干净的SERS基底,这种方法与其它基底除杂方法相比更为简单、操作性强且信号只衰减了20%。[英文文摘]Gold nanoparticles with uniform size and shape distribution were synthesized by hydroxylamine seed-mediated growing method.High density and uniform SERS(surface-enhanced Raman spectroscopy) substrates were obtained by assembling Au nanoparticles on the indium tin oxide(ITO) substrates which had been modified with(3-aminopropyl) trimethoxysilane(APTMS).Clean SERS substrates have been obtained by cleaning the assembled substrate in Plasma cleaner followed by immersion in acetic acid to remove the surface oxides.This method to remove the contaminants on the surface appears to be very simple, which only lead to a decrease of signal by 20% .973项目(2009CB930703,2007CB935603); 国家自然科学基金(20673086,20825313,20827003

    The Size and Shape Effects on the Optical Properties of Gold Nanoparticles

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    【中文文摘】纳米尺度的金属及半导体呈现出特殊的光学、电学及磁学性质,采用近年发展起来的离散偶极近似(DDA)的方法,我们分析了金纳米粒子的尺寸及形状对其光学性质的影响。粒子周围介质的影响在文中亦作了分析。计算结果显示,金纳米粒子的等离子体吸收带同时受到粒子尺寸和形状的影响,但来自形状的影响更为明显。与米氏理论及扩展的甘氏理论相比较,DDA方法在粒子尺寸不再远小于入射光波长的时候更准确,并能应用于任何形状的纳米粒子。理论计算与实验结果能较好的吻合。 【英文文摘】Metals and semiconductors exhibit unusual optical, electronic, and magnetic properties at the nanometer scale. Based on the newly developed method, discrete dipole approximation (DDA), the dependence of the optical properties of the gold nanoparticles on the size and shape was analyzed. The effects of the surrounding medium were also taken into consideration in the calculation. The calculated results show that the plasmon absorption band depends on both the size and shape of the gold noanoparticles. However , the influence of the shape is more significant . Compared to the Mieps theory and the extension , Gansp theory , the DDA method is more accurate when the dimensions of the particles are not much smaller than the wavelength of the incident light and can be applied to particles of any shape. The theoretical results are in good agreement with the experimental data.国家自然科学基金项目,批准号为 :20003008,2983306

    三叶因子1表达与胃黏膜损伤及胃癌的关系

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    目的 测定三叶因子 1(TFF1)在正常及病理条件下胃黏膜中的表达情况 ,探讨TFF1在胃黏膜损伤修复及胃癌抑制中的作用及意义。方法 应用免疫组化方法测定正常及不同病理条件下胃黏膜中TFF1的表达情况 ,通过图像分析软件分析阳性信号平均吸光度值以了解其表达情况。结果 胃炎、胃溃疡及十二指肠球部溃疡患者TFF1表达明显高于正常胃黏膜 (0 .5 1± 0 .0 5 ,0 .5 1± 0 .0 6 ,0 .5 0± 0 .0 6比 0 .4 4± 0 .0 6 ;P值均 0 .0 5 )。结论 TFF1表达随黏膜损伤程度的加重而表达增强 ,提示其在胃黏膜保护及促进上皮重建机制中具有一定的作用。TFF1在癌旁组织中表达增强提示其可能与肿瘤抑制及分化机制有关 ,而在癌组织中表达减弱可能与其分泌减少有关
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