Construction and anti-tumor effects of recombinant fowlpox virus expressing Newcastle disease virus hemagglutinin-neuramidinase gene

Hemagglutinin-neuramidinase (HN), a Newcastle disease virus-derived protein, not only mediates receptor recognition but also possesses neuraminidase (NA) activity, the ability to cleave a component of those receptors, N-acetylneuraminic acid (NAcneu, sialic acid). It is known that this protein in mammalian species, including human beings, has interesting anti-neoplastic as well as immune stimulating properties. To explore the use of the HN gene in cancer gene therapy, we constructed a recombi-nant fowlpox virus expressing the HN protein (vFV-HN) and compared the anti-tumor activity of the recombinant virus with that of wild-type fowlpox virus (FPV) in vivo and in vitro. Here we found that although B16 cells were somewhat resistant to the basal cytotoxic effect of wild-type fowlpox virus, infection with vFV-HN caused a pronounced cytotoxic effect and, the survival of tumor-bearing mice immunized with vFV-HN was significantly increased compared with the survival of mice immunized with the FPV alone. Furthermore, the immunization of mice with vFV-HN elicited a B16 tumor-specific cytotoxic T lymphocyte (CTL) response and clonal expansion of both CD4 and CD8 T cell populations in vivo. In addition, T cells from lymph nodes of mice vaccinated with vFV-HN secreted high levels of the Th1 cytokine IL-2 and IFN-γ, indicating that the regression of tumor cells is related to a Th1-type dominant immune response. These results demonstrate that vaccination with vFV-HN may be a potential strategy for cancer gene therapy.     

计算机病毒及防治研究

随着计算机技术和计算机网络的发展,计算机病毒迅速蔓延。使计算机用户的数据安全受到严重威胁。通过对计算机病毒破坏性、传染性及不可预见性等特征的研究,按照病毒的不同分类分别对其工作原理进行了分析,并探讨了一些清除计算机病毒的方法。     

防波堤基础的爆炸处理方法及应用

为了快速有效地处理防波堤地基，采用了爆炸法处理地基的新方法，包括堤端推进爆填、边坡拓宽爆填、加抛密实爆历、边坡整理爆夯等方法，通过玉环坎门防波堤工程中的应用、观察、比较，结果显示此方法费用省、工期短、沉移少、效益好，能够比较彻底的置换淤泥层，夯实堆石体，形成符合设计要求的各部位尺寸及深度。     

温室效应与天花病毒复苏

工业革命以来,大气二氧化碳浓度持续增高,温室效应进一步加强,导致全球变暖.全球变暖导致冰川融化,埋藏在冰川内的病毒有可能复苏,引起大规模的疫病.本文介绍了天花的危害以及绝灭,以天花病毒为例讨论了温室效应与已经绝灭的病毒之间的关系.     

论物理教学中创造性思维的培养

阐述了在物理教学中如何培养学生的发散思维能力、逆向思维能力和横向思维能力以及如何运用思维的迁移规律 ,并提出了培养创造性思维的几种途径 .     

Candidate Multi-Peptide-Vaccine Against Classical Swine Fever Virus Induces Strong Antibody Response with Predefined Specificity

IntroductionClassical swine fever virus(CSFV) is a pestiviruswhich causes significantmortality and morbidity inpigs.An epidemic of CSFV in a high pig densityarea can result in devastating financial losses,because few infected pigs can be effectively cured.In many countries in Europe and Asia,classicalswine fever (CSF) is controlled by vaccinationwith commercially available vaccine strains,suchas the Chinese vaccine strain(C-strain,i.e.,hogcholera lapinized virus) orsome modified-live vir…     

大袋蛾核型多角体病毒,病状及毒力的生物测定

报道了对大袋蛾核型多角体病毒、病状的观察。林间因感染大袋蛾核型多角体病毒而死亡的幼虫可分为两类：一类为纯病毒感染，另一类为病毒和细菌混合染。用不同浓度的大袋蛾核型多角体病毒感染大袋蛾卵，得多角体浓度与死亡率的直线回归方程：ｙ＝０．７８＋０．８２３ｘ，ＬＣ５０为１．１８×１０＾５ＰＩＢ／ｍＬ。用１０＾５，５×１０＾５，１０＾６ ＰＩＢ／ｍＬ感染卵，得感染时间与死亡率的关系和ＬＴ５０，分别为：ｙ＝６．     

微机病毒与防范技术

本文阐述了计算机病毒的原理,综述了传统的计算机病毒防护方法,同时介绍了一些新的防护理论及方法.