聚合酶链反应检测乙型肝炎患者血清HBVDNA与ELISA检测HBeAg、抗HBe比较研究

应用聚合酶链反应（ＰＣＲ）检测了１５３例各型乙型肝炎患者的血清ＨＢＶＤＮＡ，并与ＥＬＩＳＡ法检测的血清ＨＢｅＡｇ和抗ＨＢｅ结果比较．结果ＨＢｅＡｇ阳性８９例，ＰＣＲ法ＨＢＶＤＮＡ检出率为９２．１３％；抗ＨＢｅ阳性２７例，ＰＣＲ法ＨＢＶＤＮＡ检出率为５１．８５％；ｅ系统用性３７例，ＰＣＲ法ＨＢＶＤＮＡ检出率为４０．５４％．提示抗ＨＢｅ血清学转换不能作为乙型肝炎病毒复制与非复制、病变活动与静止的唯一指标，而应该用或同时用ＨＢＶＤＮＡ作为指标才可靠．     

大豆花叶病毒杭州分离物基因组全序列测定及其结构分析

测定了大豆花叶病毒杭州分离物（SMV－HZ）的基因组全序列。该病毒基因组全长9588个核苷酸，3‘末端具poly(A)尾，包含单一开读框，编码一个350.07kD的多聚蛋白。基因组全序列与美国SMV G2、G7、N株系及我国黄淮5号株系（Y5）的核苷酸同一性分别为93％、93％、94％和96％。多聚蛋白酶解后产生马铃薯Y病毒属典型的10成熟蛋白。SMV－YZ与G2、G7、N的不同成熟蛋白间的氨基酸同一性为89％－100％；SMV－HZ与Y5的不同成熟蛋白间氨基酸同一性则较高，达97％－100％。多重分析显示了SMV－HZ与G2、G7、N、Y5之间的序旬差异，G2、G7的P1蛋白氨基酸序列明显不同于其他株系，对SMV－HZ与我国其他株系。对SMV－HZ与我国其他分离物也进行了序列比较，对CP蛋白氨基酸序列的系统进化树分析表明SMV－HZ与BJ分离物的亲缘性最高。     

Understanding Virtual Epidemics: Children’s Folk Conceptions of a Computer Virus

Our work investigates the annual outbreak of Whypox, a virtual epidemic in Whyville.net, a virtual world with over 1.2 million registered players ages 8–16. We examined online and classroom participants’ understanding of a computer virus using surveys and design activities. Our analyses reveal that students have a mostly na?ve understanding of a computer virus influenced by mythological or anthropomorphic perspectives; only few were able to describe computational elements. The 35 students who participated in a curricular intervention in addition to the virtual epidemic shared these na?ve conceptions initially, but developed more sophisticated views after the intervention. The discussion addresses possible explanations for students’ conceptions and implications for future instructional designs.     

Antiviral activities of extracts from Hong Kong seaweeds

We extracted six Hong Kong brown seaweed species with hot water for their antiviral properties. The cytotoxicity and antiviral activity of these extracts were tested by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenlytetrezolium bromide] method, cytopathic effect reduction assay, and plaque reduction assay. The antiviral effect was further determined by flow cytometric analysis. The results showed that most of these extracts inhibited the propagation of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) standard strains with very low cytotoxicity to the host cells. The extracts ofHydroclathrus clathratus and Lobophora variegata showed more potential anti-HSV activities than the extracts of the other four seaweeds. They also had moderate anti-respiratory syncytial virus (RSV) activities but could not inhibit influenza A virus. Hydroclathrus clathratus was further extracted by diluted acid and alkali and the antiviral effects of the extracts were also detected. The result showed that the hot water extract contained the main carbohydrate components that exhibited the antiviral activities against various strains of HSV, including the acyclovir-resistant strain. HI-3, a compound fractionated from this hot water extract, showed a dose-dependent anti-HSV activity in flow cytometric analysis and plaque reduction assay.     

数字图书馆的信息安全策略

本文主要以Sun So1aris操作系统为例，简要地论述了数字化图书馆的信息安全问题，针对主流操作系统，给出了相应的安全防范策略，详细地说明了如何加强服务器的自我保护，并给出了具体实例。     

Green tea polyphenol,epigallocatechin-3-gallate,possesses the antiviral activity necessary to fight against the hepatitis B virus replication in vitro

Although several antiviral drugs and vaccines are available for use against hepatitis B virus (HBV), hepatitis caused by HBV remains a major public health problem worldwide, which has not yet been resolved, and new anti-HBV drugs are in great demand. The present study was performed to investigate the anti-HBV activity of epigallocatechin-3-gallate (EGCG), a natural-origin compound, in HepG2 2.2.15 cells. The antiviral activity of EGCG was examined by detecting the levels of HBsAg and HBeAg in the supernatant and extracellular HBV DNA. EGCG effectively suppressed the secretion of HBsAg and HBeAg from HepG2 2.2.15 cells in a dose- and time-dependent manner, and it showed stronger effects at the level of 0.11–0.44 μmol/ml (50–200 μg/ml) than lamivudine (3TC) at 0.87 μmol/ml (200 μg/ml). EGCG also suppressed the amount of extracellular HBV DNA. The data indicated that EGCG possessed anti-HBV activity and suggested the potential of EGCG as an effective anti-HBV agent with low toxicity.     

基于高分子链的入侵容忍系统病毒吸附算法

对入侵病毒的最大化吸附可以有效保证网络安全,提高入侵容忍系统的安全防护性能。传统的入侵容忍系统检测和吸附病毒的方法采用链节点的随机运动生长模型,当入侵病毒为非均匀增长状态时,对病毒的吸附能力不好。提出一种基于高分子链的病毒优化吸附方法,采用线性规划技术进行入侵容忍系统状态数据融合,把入侵容忍系统描述为马尔科夫链的5个状态,进行入侵容忍系统安全属性分析,采用链重叠检测和向量化运算模拟高分子链吸附性能,实现对入侵病毒的强力吸附。仿真实验表明,采用该算法能把4类病毒入侵数据有效吸附在高分子链模型表面,聚类效果较好,具有较好的实时性和鲁棒性。     

基于有限理性视角的网络舆情传播模型构建

[目的/意义]探究个体决策的有限理性对于网络舆情传播的影响,从网民心理的微观层面来构建网络舆情传播模型。[方法/过程]以病毒动力学理论为基础,引入考虑个体心理参照点的前景理论,构建网络舆情传播模型,并求解模型的基本再生数,进行数值仿真对基本再生数的计算结果进行验证分析。[结果/结论]网络舆情传播扩散规模,与微博用户接触到的接触消极微博内容的比例β、相关舆情事件评论或转发中传达负面情绪的评论内容占比p、被感染网民的自愈率q等有密切关系。     

一类具有非线性发生率的时滞病毒模型Hopf分支

研究了一类具有Beddington-DeAngelis非线性发生率的时滞病毒动力学模型。以时滞为参数,研究了模型的Hopf分支,得到时滞病毒模型的局部稳定性和产生局部Hopf分支的充分条件。最后,给出仿真实例,验证了理论分析结果的正确性。     

乙肝疫苗研究进展

乙型肝炎是严重威胁人类健康的三大世界性顽症之一,推行乙肝疫苗接种是预防和阻断乙型肝炎病毒感染的重要措施.分析了目前乙肝疫苗存在的伺题,介绍了1018 ISS佐剂疫苗、YIC治疗疫苗、单剂缓控释微球的情况,指出简化免疫程序、发展更有免疫效果甚至具有一定治疗作用的新型乙肝疫苗是未来的发展趋势.