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151.
为探究中华鳖天然免疫的分子机制,针对TLR2(Toll-like receptor 2)保守区设计兼并引物,从中华鳖脾cDNA中扩增出了740bp的目标序列。测序和序列分析结果表明,该序列包含富含半胱氨酸型C端结构域、跨膜结构域和TIR结构域;与斑马鱼、鸡等脊椎动物相应的TLR2序列相似性为60.5%~74.4%。采用荧光定量PCR检测中华鳖感染嗜水气单胞菌后各组织TLR2mRNA表达的变化,结果显示,感染后第24小时,中华鳖脾和外周血TLR2mRNA相对表达水平升高,其中外周血中的增幅最显著,是对照组的8.57倍;中华鳖外周血经4μg/mL酵母聚糖刺激后,第2小时TLR2mRNA相对表达水平较高。首次获得了中华鳖TLR2部分cDNA序列,并分析了不同刺激物对中华鳖TLR2mRNA转录的影响。  相似文献   
152.
为开发减毒猪霍乱沙门氏菌的活疫苗载体,通过自杀性质粒介导的细菌同源重组技术,构建了猪霍乱沙门氏菌C78-1株ΔcrpΔasd双基因缺失株,并对其生物学特性进行探讨。首先构建含有缺失1 488bp asd基因的重组自杀性质粒pREΔasd,然后与已构建完成的ΔcrpC78-1缺失株进行接合转移,采用两步法筛选无抗性的C78-1的ΔcrpΔasd双缺失株。PCR鉴定结果表明,C78-1的ΔcrpΔasd双缺失株构建成功;进一步研究表明,该缺失株的生长需要外源的二氨基庚二酸(DAP),且能稳定遗传缺失的asd基因,与C78-1相比,其血清型未发生变化,但其生长速度明显减慢。ΔcrpΔasd C78-1双缺失株可接受asd+质粒作为宿主平衡致死系统高效稳定地表达外源基因,为开发以C78-1为载体的口服多价疫苗奠定了基础。  相似文献   
153.
对14株分离自四川不同地区的基因C型鸭甲肝病毒(DHAV-C)VP1基因进行了PCR扩增、测序、序列比对分析以及抗原表位分析。结果显示,14株DHAV-C VP1基因核苷酸序列的同源性为92.2%~100%,推导氨基酸序列的同源性为85.8%~100%,与GenBank中的24株DHAV-C VP1基因的核苷酸和氨基酸序列同源性分别为87.9%~99.3%和80.8%~100%。聚类分析显示,四川华阳地区分离的6株DHAV-C的VP1基因与黑龙江分离株Du/CH/LJS/090905同属一支,3株四川邛崃地区分离株与北京分离株C-GY及福建分离株FJ01同属一支,4株四川郫县分离株与1株四川邛崃分离株处于独立的小分支,它们与其他毒株之间存在一定的遗传距离。DHAV-C VP1蛋白由240个氨基酸组成,是由α螺旋、β折叠和无规则卷曲共同组成的混合型蛋白,VP1蛋白氨基酸序列的亲水性、抗原指数和表面可及性均较高,其中212~222位氨基酸区域的亲水性、抗原指数和表面可及性最高,可能是DHAV-C VP1蛋白上的B细胞表位优势区域,为DHAV-C表位疫苗的研究提供了理论依据。结果表明,四川分离株可能由于引种等原因从全国不同地区进入四川境内。  相似文献   
154.
《国际相互影响》2012,38(1):84-128
Given both corruption's and bureaucratic inefficiency's importance for development and good governance, understanding their causes is paramount. This paper argues that majority state ownership of most the most important economic sectors of a country results in higher levels of corruption and inefficiency. When political and managerial elites both own and manage the country's most important economic resources, they have greater incentives for corrupt or inefficient behavior. These elites use national resources at their disposal more for short-term personal and political goals than for long-term economic ones. This paper tests this hypothesis on a relatively underused, but often cited, data set from the 1980s. Using a cross-national, regression analysis, this paper finds that the best predictors a country's level of corruption or bureaucratic inefficiency are these: majority state ownership of significant economic sectors, levels of GDP per capita, levels of government spending, and levels of democracy. Other factors, such as common law heritage, percent of population that is Protestant, federalism, economic freedoms, or mineral/ oil exporting, were not consistent, significant predictors of either bureaucratic inefficiency or corruption. We also argue that Tobit may be the best estimation procedure for these data.  相似文献   
155.
Traditional methods for bone pulverization typically generate heat, risking stability of DNA sample. SPEX? has developed cryogenic grinders which introduce liquid nitrogen to cool the sample and aid in the grinding process. In this study, the Freezer Mill 6970 EFM was used with two DNA extraction methods and routine downstream STR analysis procedures. DNA from as little as 0.1 g of bone powder was used to develop full STR profiles after freezer mill pulverization, and the method was reproducible. Further, no contamination was detected upon cleaning/reuse of the sample vials. There were no significant differences in DNA yield, STR alleles detected, or peak heights using the freezer mill as compared to traditional grinding, and successful DNA profiles were achieved from as low as 0.1 g of bone powder with this method. Overall, this work indicates that this cryogenic mill method may be used as a viable alternative to traditional tissue grinders.  相似文献   
156.
Objective: To detect the changes of (interleukin, IL)-1α, IL-1βand IL-13 mRNA in lung tissue and serum of drown rats, and to explore the potential value for the diagnosis of drowning in forensic practice. Methods: Eighteen SD rats were randomly divided into drowning group, blank control group and myocardial infarction group (as control group). The serum of right ventricular, the inferior lobe of right lung and the myocardium were taken from the rats in different groups. The expressions of IL- 1α, IL-1βand IL-13 mRNA in the lung tissue and the serum of right ventricular were detected by TaqMan probe method. Results: The expression differences of IL-1α, IL-1βand IL-13 mRNA in lung tissue between drowning group and blank control group, myocardial infarction group were not statistically significant (P>0.05). The expression of IL-1βand IL-13 mRNA in serum of right ventricular increased (P<0.05). The expression differences of IL-1α, IL-1βand IL-13 mRNA in serum between blank control group and myocardial infarction group were not statistically significant (P>0.05). Conclusion: The changes of cytokines IL-1βand IL-13 mRNA in the serum of right ventricular of drown rats are statistical significance, which are highly correlated with drowning. © 2018 by the Editorial Department of Journal of Forensic Medicine.  相似文献   
157.
On 26 July 2017, the Grand Chamber of the European Court of Justice rendered its seminal Opinion 1/15 about the agreement on Passenger Name Record data between the EU and Canada. The Grand Chamber considered that the decision of the Council about the conclusion, on behalf of the Union, of the agreement between the EU and Canada about the transfer and processing of PNR data must be based jointly on Article 16(2) about the protection of personal data and Article 87(2)(a) about police co-operation among member states in criminal matters, but not on Article 82(1)(d) about judicial co-operation in criminal matters in the EU of the Treaty on the Functioning of the EU. The Grand Chamber also considered that the agreement is incompatible with Article 7 on the right to respect for private life, Article 8 on the right to the protection of personal data, Article 21 on non-discrimination and Article 52(1) on the principle of proportionality of the Charter of Fundamental Rights of the EU since it does not preclude the transfer, use and retention of sensitive data. In addition to the requirement to exclude such data, the Grand Chamber listed seven requirements that the agreement must include, specify, limit or guarantee to be compatible with the Charter.The opinion of the Grand Chamber has far-reaching implications for the agreement on PNR data between the EU and Canada. It has also far-reaching implications for international agreements on PNR data between the EU and other third states. Last, it has far-reaching implications for Directive 681 of 27 April 2016 on PNR data.  相似文献   
158.
Since the termination of its nuclear weapons programme, commenced in 1989 and verified by the International Atomic Energy Agency's (IAEA) in 1993, successive South African governments have consistently advocated the country's commitment to nuclear non-proliferation. South Africa has secured a niche role through norm construction and state identity for itself through its nuclear diplomacy with the IAEA. The article explores aspects of South Africa's nuclear diplomacy with the IAEA as an example of niche diplomacy. Therefore, it traces South Africa's diplomatic relations with the IAEA, starting with the IAEA's verification process and the implementation of a Safeguards Agreement (1989–1994) through the conversion of South Africa's research nuclear reactor (1991–2005); South Africa's position on greater representation for developing countries on the IAEA's Board of Governors; its ambition to be elected to the position of IAEA Director General (2008–2009); and its refusal to support the establishment of a nuclear fuel bank in Russia under the IAEA's auspices (2009–2010).  相似文献   
159.
目的探讨GRIN1基因启动子区两个单核苷酸多态性位点-855 G/C、-1140 G/A遗传多态性与偏执型精神分裂症的相关性及法医学意义。方法采用PCR限制性片段长度多态性(restriction fragment length polymorphism,RFLP)结合PAGE法对中国北方汉族183例健康无关个体和172例偏执型精神分裂症患者GRIN1基因5′端的-855 G/C和-1140 G/A位点多态性进行检测,采用χ2检验人群中基因型分布是否符合Hardy-Weinberg平衡定律,并比较两组人群中基因型和等位基因频率分布的差异。结果两组群体基因型分布符合Hardy-Weinberg平衡定律。-855 G/C位点基因型分布在对照组女性和实验组女性间的差异具有统计学意义(P0.05),-1140 G/A位点基因型和等位基因频率分布在对照组和实验组间及两组女性间差异具有统计学意义(P0.05)。结论 GRIN1基因启动子区-1140 G/A位点单核苷酸多态性可能与精神分裂症存在相关性;精神分裂症发生的遗传学因素可能存在性别倾向,可为精神分裂症的司法鉴定提供参考。  相似文献   
160.
The opportunities to analyse the genetic variations related to the risk of addiction are of interest to forensics, who beside their involvement in drugs-related fatalities may also be required to assess driving and working ability as well as permanent invalidity due to drugs-related conditions. Several genetic variants have been shown to be associated with heroin addiction. The most investigated gene is OPMR1 that encode the μ-opioid receptor. The purpose of this study was to examine the contribution of genetics variants in OPRM1 to the susceptibility to addiction.  相似文献   
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