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121.
参考Genebank发表的传染性支气管炎病毒(IBV)S1纤突蛋白基因序列,自行设计合成了1对引物,对IBV青岛腺胃分离株(SD/97/02)RNA进行RT-PCR扩增.产物经琼脂糖凝胶电泳分析,呈现1条1657 bp的条带,将其克隆入pMD18-T载体中,并进行序列测定,证实为S1基因.将此重组质粒命名为pMDQXS1.  相似文献   
122.
The vast majority of tests of major criminological theories have been conducted on youths in school settings. Following Hagan and McCarthy’s (1997) admonition to engage in “street criminology,” the current study surveyed 254 juveniles drawn mainly from impoverished neighborhoods in Uruguay, who were either confined or in an alternative justice program. Due to limited literacy skills, all youths were interviewed regarding theoretical measures and their delinquent involvement. The results revealed that self-control was unrelated to delinquency in this sample. By contrast, social learning factors and stressful life events were found to increase delinquent participation. The results suggest that the effects of the field’s core theories are general, accounting for as much or more variation in the sample of street youths as among youths attending conventional U.S. schools. The policy implications of the findings are explored.  相似文献   
123.
高致病性猪繁殖与呼吸综合征活疫苗的研制   总被引:1,自引:0,他引:1  
将高致病性猪繁殖与呼吸综合征病毒致弱株TJM株与耐热冻干保护剂混合制备弱毒活疫苗,并对该活疫苗进行安全性、免疫保护效果和保存期试验。结果显示,4~5周龄仔猪接种该疫苗后体温正常,无任何临床可见异常。该疫苗接种猪对强毒攻击的保护率达4/5以上;将其置于2~8℃保存24个月,病毒效价降低不超过100.5 TCID50/mL。表明该疫苗对猪安全,免疫保护效果良好,且便于保存。  相似文献   
124.
目的 从自然界选出不同类型的菌种,并筛选可以转化刺囊酸的菌株.方法 用微生物对刺囊酸进行转化,筛选出能转化刺囊酸的菌种,采用薄层色谱法(thin layer chromatography,TLC)和高效液相色谱法(high performance liquid chromatography,HPLC)检测转化反应的发生...  相似文献   
125.
According to Agnew’s General Strain Theory, many individuals who experience strain are more likely to engage in crime or become delinquent. To date, past research has examined the relationship between victimization and fear of crime, as well as the corresponding relationship between fear of crime and self-protective behaviors. Yet, the mediating role fear of sexual assault may have in accounting for the association between prior sexual assault victimization and self-protective behaviors has not been evaluated. The current study addresses this gap in the literature using data collected from a random sample of college students from 12 universities in the United States. The results indicated that the relationship between prior sexual assault victimization and self-protective behavior is partially mediated by fear of sexual assault. The study concludes with a discussion of implications and limitations, as well as directions for future research.  相似文献   
126.
目的观察和分析STR-typer 10G/F试剂盒在单亲鉴定中的作用。方法随机抽样湖北地区汉族个体206人静脉血样,Chelex-100法提取基因组DNA。采用STR-typer 10G/F试剂盒进行复合扩增,分型并计数基因型并计算基因频率、基因座杂合度(H)、标准三联体非父排除率(PE3)和二联体非父排除率(PE2)。结果 9个STR基因座等位基因数9~14个,基因型分布观察值与Hardy-Weinberg平衡理论值的差异均无显著性(P>0.05),杂合度在0.75以上,平均非父排除率0.57~0.75;STR-typer 10G/F试剂盒累积非父排除率(PE3)0.999 973,合并使用Identifiler Plus系统,累积非父排除率可达0.999 999 967 6。结论 STR-typer 10G/F系统多态性程度基本接近Identifiler Plus系统,在单亲鉴定时,可作为Identifiler试剂盒的有效补充。  相似文献   
127.
Cyber bullying has become more pervasive as a result of advances in communication technology such as email, text messaging, chat rooms, and social media sites. Despite the growth in research on correlates associated with engagement in cyber bullying, few studies test the applicability of criminological theories to explain engagement in cyber bullying. This study applies data from the 2009/2010 Health Behavior in School-Aged Children (HBSC) study to examine whether individual and social factors associated with general strain theory explain why children engage in cyber bullying. Multivariate logistic regression analyses were conducted to identify significant factors associated with engagement in cyber bullying. The multivariate logistic regression results show that students who experienced strain engage in cyber bullying. The regression analysis also shows a positive relationship between participation in traditional bullying and engagement in cyber bullying.  相似文献   
128.
Most scholars agree that low socio-economic status is associated with an elevated risk for violent victimization as well as offending. Nevertheless, it has been suggested that certain forms of violence—particularly intimate partner violence (IPV)—are more equally distributed in the population, not concentrating on the lower social strata as strongly as other forms of violence. In this paper, we examine the association between financial strain, measured on the household level, and two different types of victimization: IPV and violence committed by a person unknown to the victim. The analysis is based on the 2013 sweep of Finnish National Crime Victim Survey (n = 6,999), a nationally representative survey incorporating a mix of postal and web-based survey methodology. Multivariate analyses indicate that the risk for both kinds of victimization is highest among those who report financial difficulties. Moreover, the association between IPV and financial strain appears stronger when less serious violent incidences are excluded from the analysis.  相似文献   
129.
STEPHEN W. BARON 《犯罪学》2004,42(2):457-484
Using a sample of homeless street youth, this research examines how specific forms of strain–emotional abuse, physical abuse, sexual abuse, homelessness and being a victim of robbery, violence or theft, relative deprivation, monetary dissatisfaction and unemployment–lead to crime and drug use. It also explores how strain is conditioned by deviant peers, deviant attitudes, external attributions, self‐esteem and self‐efficacy. The results reveal that all ten types of strain examined can lead to criminal behavior either as main effects or when interacting with conditioning variables. The results are discussed in light of general strain theory and suggestions are offered for future research on this topic.  相似文献   
130.
利用鸡胚分离法由发生肾病变型传染性支气管炎 (IB)的病鸡分离到嗜肾型传染性支气管炎病毒 (NIBV)W株 ;再通过SPF鸡胚连续传代 ,获得了NIBV疫苗毒株W93;继而借助RT PCR法扩增了其S1基因 ,并测定了S1基因的核苷酸序列 ,分析了与相关毒株间的同源性。结果显示 ,W93株在鸡胚中的病毒产量达 10 7.8EID50 /0 .1mL ,适用于所有日龄的雏鸡 ;W93S1基因的核苷酸序列与马萨诸塞型的M4 1株、H52 株和H12 0 株的同源性很高 ,分别为 96 .9%、96 .8%和 97.1%。表明 ,W93可作为制备IB弱毒疫苗的毒株  相似文献   
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