血管内皮生长因子与肿瘤新生血管的关系

目的：综述血管内皮生长因子(VEGF)与肿瘤新生血管的关系及近年来的研究现状。方法：通过对近年来血管内皮生长因子促进肿瘤血管生成方面的相关献的回顾、总结VEGF及VEGF与肿瘤新生血管的关系。结果：血管生成在肿瘤生长中占有重要地位，而VEGF在促进肿瘤血管生成因素中起到最关键的作用。结论：VEGF是目前发现的最重要的刺激微血管因子，针对VEGF的抗血管生成治疗可能给恶性肿瘤的治疗带来新的契机。     

中国技术市场规模扩张原因的实证检验

采用格兰杰因果分析法，依据需求拉动和技术推动理论，对中国技术交易规模扩张的原因进行了实证检验．结果表明：中国技术市场规模扩张的类型属于需求拉动的规模扩张，而不属于技术推动的规模扩张．     

东中西部地区经济增长的要素投入作用比较

运用经济增长理论,以新经济增长模型为基础,对我国东中西部各地区1978～1998年劳动、资本、技术的增长率及对GDP的贡献进行分析,比较东中西部地区在要素投入增长、全要素生产率增长对经济增长贡献方面的差异。结果表明:我国现阶段的经济增长主要还是靠要素投入来拉动;但经济发达的江苏、浙江、广东、上海和北京这些省市的固定资产投资已经趋于饱和,其投资的边际产出已经很低,造成其资本利用效率低下,应着重进行技术创新,提高全要素生产率的贡献。而西部地区的省市应该是资金首先投向的地方。由于先阶段一个地区的经济增长率主要由其资本增长率决定,因此,西部开发要把重点放在提高各省市的资本生产率,即要提高其资金的使用效率,进而提高整个地区的综合生产率。     

气泡塔熔融结晶器中传递与晶层生长

分析了气泡塔结晶器熔融结晶过程中自熔体向晶层界面的热、质传递特征，建立了描述该过程晶层生长的稳态模型。在自熔体向晶层界面对流传热膜系数的计算中，将弹单元分为弹状气泡周围液膜区、尾迹区及液塞段3段，各段的平均对流传热膜系数不同。分别在表观气速0.04和0．08m/s下，用模型对己内酰胺晶层生长进行了计算，计算结果与实验结果基本吻合。     

高校科技产业发展的思考

本文首先分析国内外对高校参与经济活动的理论争论以及众多争论背后的本质问题,在此基础上研究中国高校产业特征及存在的问题,发掘其动因,并从三方面分析了高校产业的成本收益。最后根据我国的实际情况,提出相应建议,以便更好地发挥高校的作用,促进中国产业界的技术进步。     

统筹城乡经济社会发展:解决“三农”问题的重大战略

统筹城乡经济社会发展是解决“三农”问题、实现城乡经济良性循环的必然选择;是解决“三农”问题的重大创新;是全面建设小康社会内在要求的深刻体现。我们要通过深化改革,改变城乡二元结构,建立平等和谐的城乡关系,推进城乡经济社会统筹发展。     

Inhibitory effect of the adenovirus type 5 E1A protein expressed in the yeast system

The human adenovirus type 5 E1A, a tumor- suppressor gene[1], codes for two major related proteins of 243 amino acids (12S) and 289 amino acids (13S) by al-ternative splicing in two exons[2]. Studies have been shown that E1A can regulate expression of many genes and cell cycle[3]. Both in vitro and in vivo experiments indicated that E1A could induce tumor cells differentia-tion, convert tumor cells into an epithelial phenotype, in-hibit tumor cell growth and metastasis and strongly en-ha…     

Impact of the Small Town Construction on Original Inhabitants in the Three Gorges Reservoir Area--A Case Study in Lishu Village, Changling Town, Chongqing Municipality, China

Based on the five-year long dynamic tracking and investigation of the peasant households of the Lishu village, the influences by small town construction on the economy and employment of the original peasant households are discussed. On the one hand, small town construction plays a positive role in adjustment of the industrial structure of the original peasant households and in the transfer of their employment towards non-agricultural industries. On the other hand the economic growth of the original peasant households is not so well sustainable, and is so fluctuating. Moreover,the unbalance of income distribution of the said households has been furthered, and small town construction has made the existing labor surplus of the original peasant households more serious, particularly the women labor surplus.     

Inhibitory effect of the adenovirus type 5 E1A protein expressed in the yeast system of the human tumor cell growth

Adenovirus 5 type E1A as a tumor suppressor gene can inhibit tumor growth and enhance the censitivity of chemotherapy and radiotherapy.E1A have the ability to integrate into the host genome,resulting in long-time expres-sion that induces Rb gene inactivation and animal cells im-mortalization.This prompted us to select the E1A protein for treatment of cancer in order to overcome the limitations of E1A gene therapy.Thus,we firstly comstructed E1A eu-caryotic expression vector (pPIC9/E1A),transformated the pichia pastoris yeast cells(GS115) and screened the high-expressing recombinant strains.The positive yeast strains were cultured in the shake flask,and induced for 3d.The crude E1A protein was purified using two steps of col-umu chromatography on HiTrap Q and HiTrap SP.The pu-rified E1A protein was identified by SDS-PAGE and Western blot.E1A protein was mostly located at cellular unclear when Cheriot delivered E1A protein into cells.The analysis in vitro indicated that the E1A protein arrested LN686 cell cycle at G2/M phase,and significantly inhibited the growth of LN686 tumor cells.The current studies firstly provided an experimental basis to further develop E1A protein for tumor treatment.     

1,3-苯二氧基二乙酸二芳酯的合成及植物生长调节活性

以PEG 4 0 0为催化剂 ,在液 液相转移催化条件下合成了一系列新的 1,3 苯二氧基二乙酸二芳酯 .用元素分析、IR以及1 HNMR确定了它们的结构 .初步生物活性试验表明 ,该类化合物对小麦幼苗的生长有一定的促进作用 .