基于C/S的计算机生物病毒免疫系统

计算机病毒对计算机安全构成的威胁日益突出,传统的病毒检测技术已无法有效地防御病毒,作者在研究了病毒检测技术和现有计算机病毒免疫系统的基础上,提出了基于Client/Server模式的计算机病毒智能免疫系统。     

高效价麻疹抗血清的制备及检定

目的制备高效价麻疹抗血清,用于疫苗检定中病毒鉴别、支原体检测、麻腮二联和麻腮风三联疫苗的联合滴定试验。方法将麻疹病毒L4株于Vero细胞中传代培养,获得高滴度病毒原液,制备免疫抗原,分别经腹腔注射法、耳静脉注射法和背部皮下多点注射法免疫家兔,制备抗血清,并按规程要求对抗血清进行检定。结果采用腹腔注射法、耳静脉注射法和背部皮下多点注射法免疫家兔所制备的抗血清的中和效价分别为1∶960、1∶2 560和1∶3 840,经检定,3种方法制备的抗血清均达到疫苗检定的使用要求。结论背部皮下多点注射法制备的麻疹抗血清效价最高,且操作简单,可作为制备高效价麻疹抗血清的最佳方案。     

Influence of water chemistry and travel distance on bacteriophage PRD-1 transport in a sandy aquifer

Experiments were conducted to evaluate the impact of groundwater chemistry and travel distance on the transport and fate behavior of PRD-1, a bacteriophage employed as a surrogate tracer for pathogenic enteric viruses. The experiments were conducted in the unconfined aquifer at the United States Geological Survey Cape Cod Toxic-Substances Hydrology Research Site in Falmouth, Massachusetts. The transport behavior of bromide (Br(-)) and PRD-1 were evaluated in a sewage-effluent contaminated zone and a shallower uncontaminated zone at this site. Several multilevel sampling devices located along a 13-m transect were used to collect vertically discrete samples to examine longitudinal and vertical variability of PRD-1 retardation and attenuation. The concentration of viable bacteriophage in the aqueous phase decreased greatly during the first few meters of transport. This decrease is attributed to a combination of colloid filtration (attachment) and inactivation. The removal was greater (10(-12) relative recovery) and occurred within the first meter for the uncontaminated zone, whereas it was lesser (10(-9) relative recovery) and occurred over 4m in the contaminated zone. The lesser removal observed for the contaminated zone is attributed to the influence of sorbed and dissolved organic matter, phosphate, and other anions, which are present in higher concentrations in the contaminated zone, on PRD-1 attachment. After the initial decrease, the aqueous PRD-1 concentrations remained essentially constant in both zones for the remainder of the tests (total travel distances of 13 m), irrespective of variations in geochemical properties within and between the two zones. The viable, mobile PRD-1 particles traveled at nearly the rate of bromide, which was used as a non-reactive tracer. The results of this study indicate that a small fraction of viable virus particles may persist in the aqueous phase and travel significant distances in the subsurface environment.     

Virus removal during simulated soil-aquifer treatment

Removals of indigenous coliphage and seeded poliovirus type 1 during simulated soil-aquifer treatment were evaluated during transport of secondary effluent under unsaturated flow conditions in 1-m soil columns. Independent variables included soil type (river sand or sandy loam) and infiltration rate. Removal of coliphage was in all cases less than removal of poliovirus type 1 (strain LSc-2ab), supporting contentions that indigenous coliphage can act as a conservative indicator of groundwater contamination by viral pathogens of human origin. Coliphage retention was significantly more efficient (p<0.001) in the finer-grained sandy loam (93%) than in sand (76%). Increasing reactor detention time from 5 to 20 h increased coliphage attenuation from 70% to 99% in a 1-m sand column. There was a significant linear correlation (p=0.012) between log-transformed (fractional) coliphage concentration [log(C/C(0))] and reactor detention time. Re-mobilization of attached coliphage occurred during simulated rainfall using low-ionic-strength water. Inhibition of aerobic respiration resulted in significantly less efficient coliphage attenuation (p=0.033), suggesting the involvement of aerobic microorganisms in the survival/retention of this virus.     

烟草抗病新品系“转基因NC89”的大田试验

对转“黄瓜花叶病毒外壳蛋白（ＣＭＶＣＰ）＋卫星ＲＮＡ”嵌合基因的工程ＮＣ８９的Ａ、Ｂ、Ｃ三个纯系以及转“ＣＭＶＣＰ＋烟草花叶病毒外壳蛋白（ＴＭＶＣＰ）”嵌合基因的工程ＮＣ８９Ｔ纯系进行了田间抗病性鉴定及农艺性状测试，结果表明：不论在人工接毒或自然发病条件下，转基因ＮＣ８９的花叶病病情指数都明显低于未转基因ＮＣ８９对照，其中Ｂ纯系的抗病性最高，在上述条件下，相对防效分别达到８０．２％、９２．９５％。在农艺性状方面，转基因ＮＣ８９较对照有所改善，但种性未变。     

Detection and identification of transgenic virus resistant papaya and squash by multiplex PCR

Two separate multiplex PCR assays were developed for the detection of transgenic papaya and transgenic squash. Papaya line 55-1 contains a genetic insertion consisting of the coat protein gene of Papaya ringspot virus strain p and is resistant to infection by this virus. A multiplex PCR was developed to specifically amplify the papaya ringspot virus coat protein transgene construct and an endogenous papaya gene sequence. A third primer set was designed to amplify the -glucuronidase gene construct, which can distinguish between the commercial and noncommercial papaya lines 55-1 and 63-1. Squash line ZW-20 contains genetic insertions of the coat protein genes from Watermelon mosaic virus II and Zucchini yellow mosaic virus and is resistant to these two viruses. Squash line CZW-3 is similar to ZW-20 but additionally confers resistance to Cucumber mosaic virus. A second multiplex assay was developed to detect and differentiate squash lines ZW-20 and CZW-3 in a single reaction.     

诺沃克类病毒

诺沃克类病毒是引起急性非细菌性胃肠炎暴发的病原之一 ,常通过污染的食物和水而传播。通过分子生物学技术能够从大便标本中检出该病毒。诺沃克类病毒也称为小圆结构病毒 ,并归类为杯状病毒成员。可分为两个不同的基因组 ,基因 Ⅰ 组 (GⅠ)和基因Ⅱ 组 (GⅡ)。诺沃克类病毒多在餐厅、护理中心、医院、学校、旅游等地爆发流行。     

“棉烟灵”防治烟青虫、斜纹夜蛾和烟蚜试验

20 0 0 - 2 0 0 1年进行了利用病毒制剂“棉烟灵”防治烟青虫、斜纹夜蛾和烟蚜研究。结果表明 ,“棉烟灵”对烟青虫有较好防效 ,对斜纹夜蛾无效。“棉烟灵”加辛硫磷的混剂对烟蚜有兼治作用。“棉烟灵”在田间的持效达 36d左右 ,药效呈线性递减 ,每天递减率为 3.14 % ,防效与烟青虫幼虫密度无关。依靠烟青虫幼虫的移动来实现病毒的扩散范围有限 ,幼虫感染病毒后的第 5d达到死亡高峰。     

广州市一起群体性诺沃克病毒性胃肠炎调查分析

诺沃克病毒的感染是成人和大龄儿童流行性非细菌性肠炎的主要病因 ,但由于检验方法尚不普及 ,临床上确诊的较为少见。 2 0 0 3年 10月广州市越秀区某小学学生出现呕吐、腹痛、腹泻、发热等症状 ,人数达 82人 (其中 1名老师 ) ,经广州市、越秀区疾病预防控制中心反复多次详细的现场调查 ,并在广东省疾病预防控制中心的技术支持下 ,利用RT PCR方法在病人粪便标本中检测到诺沃克类病毒。首次在广州市证实该事件的病因是诺沃克类病毒引起的急性胃肠炎。     

局域网中ARP病毒欺骗攻击及防御方法

局域网中ARP病毒问题会严重影响到网络的正常运行,甚至造成大面积网络不能正常使用.通过了解ARP病毒工作原理、分析ARP病毒攻击机理,从网络管理和网内主机管理两方面给出局域网内有效地防御ARP病毒的对策.