水貂肠炎病毒疫苗株和野毒株PCR-RFLP鉴别方法的建立

为了建立水貂肠炎病毒(MEV)疫苗株与野毒株的鉴别检测方法,根据GenBank中的水貂肠炎病毒序列设计了1对引物,用来扩增包含水貂肠炎病毒NS1基因在内的2 013bp大小的片段。通过对国内疫苗毒MEVB株及其他细小病毒参考株的NS1基因序列比较发现,疫苗毒MEVB株NS1基因核苷酸1401位的碱基由T变为C,致使1399位～1404位的核苷酸构成由ATTGAT变异为ATCGAT,多了1个限制性内切酶ClaⅠ酶切位点,其他MEV分离毒株中均未出现此酶切位点。用特异性引物扩增出2 013bp的目的片段后,再用限制性内切酶ClaⅠ进行酶切分析,疫苗毒MEVB株被切割成1 404bp和609bp的2个片段,国内其他分离株均未出现上述片段。结果表明,所建立的PCR-RFLP方法可以区分疫苗毒MEVB株和野毒株。     

口蹄疫病毒基因组IRES和Poly(C)之间功能未知区一级和二级结构分析

用RT-PCR法,以口蹄疫病毒(FMDV)WH/99株牛舌水泡皮为材料,提取RNA及扩增目的cDNA,然后与pGEM-T Easy载体连接并转化JM109菌株,再经重组质粒电泳、PCR和EcoRⅠ酶切鉴定;用DNAstar软件比较功能未知区的序列差异,以RNAdraw软件分析它们的二级结构.结果表明,7株FMDV的功能未知区序列长度介于207-256个核苷酸;序列分析表明,WH/99与AsiaⅠ 63/72、A24/Cruzeiro、TWTY/97和TWCP/97的序列差异最大,预示此区段可能与病毒感染嗜性有关;二级结构分析表明,A24/Cruzeiro、Asia Ⅰ 63/72和TWCP/97均有5个结构域,WH/99和TWTY/97具有6个结构域.TWTY/97和TWCP/97二级结构的差异可能是TWTY/97功能未知区第20位插入的"C"所致,而O1K/66和O1Campos仅有3个结构域.2株猪O型FMDV功能未知区5′端存在着连续的核苷酸缺失现象,最多达52个,唯有3株牛O型FMDV(O1K/66、O1Campos和WH/99)在上述位置无任何缺失.     

微生态制剂—XA1503菌粉的研制和应用

从5株不同的蜡状芽胞杆菌中筛选出XA1503菌株,并与市售“止痢灵”菌种DM423蜡状芽胞杆菌进行了毒性和安全性试验的比较,证明XA1503菌株是一株十分安全无害的菌。用XA1503菌株制成的菌粉,经实验室和临床试验结果表明,它是一种有效的微生态制剂,用于畜禽肠道疾病的预防和治疗,特别是仔猪、犊牛、羔羊、仔犬的腹泻、鸡白痢有明显效果。     

雏鹅新型病毒性肠炎病毒弱毒株的培育及其特性研究

应用在鸭胚成纤维细胞上连续传代的方法 ,获得了由雏鹅新型病毒性肠炎病毒强毒株(NGVEV CN株 )致弱的弱毒株 (CN4 0 株 )。该弱毒株TCID50 为 10 - 8.0 83,具有良好的安全性和稳定性 ,在易感 1日龄雏鹅连传 8代不返强。该弱毒具有良好的免疫原性 ,最小免疫剂量为 10 0 0 0TCID50 ,免疫后 3d产生部分免疫力 ,5d产生坚强免疫力。口服免疫效果最好 ,对雏鹅免疫期在30d以上。该弱毒株能够干扰强毒在雏鹅体内繁殖 ,进入鹅体后能够进行一定程度繁殖并排泄出体外 ,使同居雏鹅感染并获得一定程度免疫力。临床使用后可极显著降低雏鹅的死亡率。     

Abating the Consequences of Managerialism on the Forgotten Employees: The Issues of Support,Control, Coping,and Pay

With the widespread and continuing adoption of managerialism in the public sector, ignoring the impact of change on employees could prevent managerialism from achieving its goals. Subsequently, this study investigates the efficacy of an augmented demand-control-support (D-C-S) model in predicting three of the key employee outcomes in the context of organizational change—psychological health, job satisfaction, and organizational commitment. Analyses of a survey of 207 employees in the Australian public sector, a sector that has undergone, and continues to undergo, substantial change toward managerialism, found that the augmented D-C-S model explained a significant proportion of the employee outcomes in the public sector context. The most important variables were work-based social support and job control. Coping style and perceptions of work conditions, such as pay, were also significant. The augmented D-C-S model provides a useful, proven tool for managers operating within the contemporary public sector.     

Street justice: a theoretical paradigm

Three theoretical perspectives examine the role of justice as a means of informal social control and as a reactionary process to dynamics of social strain and subcultural demands. This theoretical analysis is then applied to concepts of justice, including retributive, distributive, restorative, and procedural. The derived street justice paradigm incorporates these various forms of justice as they are linked with cultural imperatives associated with street culture and street crime. The linking of these concepts provides a clearer understanding of the motives and means of exacting justice in a state of heightened relative strain that is pronounced by a preference for revenge and violence. Implications for policy, future study, and theoretical expansion are discussed with particular emphasis on the application of the paradigm to non‐street crime and to policies directed toward involving community members in the justice process.     

土霉素降解菌的筛选及其降解特性研究

为了获得对土霉素具有降解活性的细菌,在建立无机盐培养基中土霉素含量的高效液相色谱(HPLC)检测方法的基础上,从某土霉素生产厂污水池底泥中分离能够高效降解土霉素的菌株,建立了土霉素高效降解菌的筛选模型,并进行了降解菌株降解特性的研究。结果表明,分离到的1株能高效降解土霉素的菌株(Oxy2),经初步鉴定为蜡样芽孢杆菌(Bacillus cereus)。该菌株最高可降解200 mg/L土霉素,对土霉素降解的最适条件为温度35℃,pH 7.0,土霉素浓度50 mg/L,装液量80 mL。此外,添加不同的碳源或氮源均有利于细菌对土霉素的降解,其中加入5 g/L可溶性淀粉或酵母浸液影响更显著。金属离子对菌株降解土霉素的速率亦有影响,其中添加1 g/L的Fe3+和Zn2+时可提高Oxy2菌株对土霉素的降解率,而Co3+,Pb2+,Cr3+可明显抑制细菌对土霉素的降解率。     

鸡马立克氏病病毒HC135分离株的致病性

从辽宁省某鸡场疑似马立克氏病发病鸡外周血淋巴细胞中分离到1株适应鸭胚成纤维细胞生长的马立克氏病病毒(MDV),经蚀斑克隆和细胞传代,成功培育了1株增殖性能稳定的MDV细胞毒株,命名为HC135株;将HC135株第4代细胞培养物分别人工感染非免疫和不同疫苗免疫的SPF鸡,分析其对鸡的致病力,分离毒株攻毒对照组鸡的发病率为100%(10/10),死亡率为30%(3/10);HVT疫苗及HVT/SB1双价疫苗对分离毒株的保护指数分别为22.2和40.0。结果表明,该毒株可以突破HVT疫苗和HVT/SB1双价疫苗的免疫保护,具有特超强毒株(vv+MDV)的特点;也证实了我国商品鸡群中存在vv+MDV毒株。同时比较了HC135株与14株参考毒株的Meq基因序列,发现其Meq基因的ORF内没有基因片段的插入或缺失,推导的氨基酸存在点突变,这种突变符合高毒力毒株的变异规律。     

Pathogen detection using a liquid array technology

Abstract: Low concentrations of microbial pathogens in pure and mixed samples were detected using a bead‐based, liquid array technology. A 20‐bp sequence in the 23S rRNA gene, rrl, was amplified in four microorganisms: Bacillus cereus, Escherichia coli, Salmonella enterica and Staphylococcus aureus. PCR products were positively identified with the Luminex^® 100? system. The system could detect very low amounts of DNA and the instrument response was proportional to the input concentration. The lower limit of detection (LLD) was determined to be 0.5 ng for B. cereus and E. coli and 2 ng for S. enterica. The LLD for S. aureus was not determined as the instrument response was still above the threshold when quantities of DNA as low as 0.25 ng were used. The platform positively identified organisms present in mixed samples even when the minor component was overshadowed by a 10‐fold excess of the major component.