注册会计师行业面临的挑战及对策

我国注册会计师行业正面临着严峻的挑战.注册会计师迫切需要提高自身的业务素质,加强职业道德修养;会计师事务所必须加强制度建设.提高竞争力;注册会计师协会应强化监督职能.     

用场效应管放大电路测量可逆电池的电动势

本文介绍应用场效应管放大电路来测量电池电动势的新原理与新方法.该测量原理与方法简单、实用,不但更新了传统的测量原理,而且也提高了测量精度和学生的学习兴趣及动手能力.     

动态车辆调度系统的滚动时域调度算法

提出了一类特殊的动态车辆调度问题--动态独占性带时间窗口装卸货问题.给出了问题的数学描述,分析了其静态性质,并把问题简化为不对称带时间窗口旅行商问题.提出了求解该动态问题的滚动时域调度算法,通过时域的不断滚动,不仅可以跟踪问题的动态变化,还由于每次滚动只对部分客户进行处理,可以减少问题的求解时间.并分析了算法的3个要素:当前客户窗口、当前客户窗口的调度和滚动策略.测试结果验证了算法在求解动态车辆调度问题中的有效性.     

建筑设计中PDM系统开发的关键问题及其实现技术

根据PDM系统建设的实际,提出了开发PDM系统中的几个关键问题,主要包括角色管理、工作流管理、片本控制以及应用软件集成等,对于每一种问题均给出了相应的解决方案。     

协调运用交际教学法和传统教学法

本文针对目前大学专业英语教学中存在的问题，分析了交际教学法与传统教学法的利弊并提出了将两者协调运用的方法。     

水稻免耕栽培生理基础——Ⅱ.免耕水稻的光合特性

威优64、陆青早1号作为试验材料,免耕能提高功能叶的光合速率、生育前期功能叶的呼吸强度、绿叶面积、叶绿素和可溶性蛋白含量,并延缓它们在生育后期的下降速率,降低后期功能叶的呼吸速率。主分量分析说明,在研究光合作用时,光合强度、叶绿素、可溶性蛋白质、叶片含氮量,可以任意选择一个作为光合特性指际。粒/叶比说明,免耕对源的改善较对库的改善较好些。     

试析隋李谔《上书正文体》

东晋以降,文风浮华,内容空洞,“损本逐末”。隋初,治书侍御史李谔提请文帝杨坚用行政手段端正公文文。本文以其《上书正文体》为研究对象,从文种学角度出发,探索“上书”的历史渊源与向“奏”文种转化;分析后世沿用残留状态的上书之原因,印证该实例处的文种演化阶段。从文体写作的角度出发：分析该文所崇尚的“儒素”之内涵,是强调公文以实用为本。“儒”指内容实在,“素”之指文字朴实。与文艺作品基本出发点,以意境为统率,情趣为根本,欣赏为目的,明显有异。进而分析李谔的主张在公文写作指导思想上的局限性。     

Homoharringtonine induces apoptosis of endothelium and down-regulates VEGF expression of K562 cells

Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. How ever, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry. The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner. Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.     

Cloning, expression, purification, and characterization of LC-1 ScFv with GFP tag

INTRODUCTION Because of its low molecular weight and ability to fluoresce independently (George, 1997), the new molecular tag, green fluorescent protein (GFP), has become more and more popular after Prasher et al.(1992) cloned its cDNA in 1992. There are many reports describing the co-expression of GFP and a specific antibody or cytokine gene, with the fusion protein expressing the fluorescent activity and bio-logical activity of the complement protein (Haraguchi et al., 1999; Mclean…