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41.
边缘无浆体MSP5蛋白基因的克隆及原核表达 总被引:2,自引:0,他引:2
参照已发表的边缘无浆体主要表面蛋白5(MSP5)基因的核苷酸序列,设计了1对特异性引物,以边缘无浆体基因组DNA为模板,采用PCR技术扩增获得了MSP5蛋白基因。将其克隆到pGEM-T Easy载体,并进行测序分析。结果表明,克隆的MSP5基因与GenBank上登录的Florida株MSP5蛋白基因的序列同源性达98.6%,编码氨基酸的同源性为99.0%,并且该序列包含有完整的开放阅读框,大小为633 bp。将该基因亚克隆入原核表达载体pGEX-4T-1,构建了重组原核表达载体。将其转化到DH5α宿主菌中,用IPTG进行诱导表达,实现了融合表达,表达产物的分子质量为45 ku。Western-blot分析表明,此表达产物能够被抗边缘无浆体阳性血清所识别。 相似文献
42.
The accountability of international development NGOs (INGOs) has attracted a great deal of interest from academics and development practitioners. INGO accountability falls into two categories: practical accountability (for the use of inputs, the way activities are performed, and outputs) and strategic accountability for INGOs' performance in relation to their mission. This article presents a conceptual framework for exploring INGO accountability. It is based on information collected through a literature review and semi-structured interviews with representatives from 20 UK-based INGOs. The research found that INGOs tend to use a number of quality-assurance mechanisms to achieve ‘practical’ accountability. However, it is suggested that this kind of accountability will not necessarily enable INGOs to achieve their missions to alleviate poverty and eliminate injustice. Furthermore, the predominant use of practical accountability has led to a number of gaps in INGO accountability. It is suggested that, like the term ‘participation’ before it, accountability has been co-opted for its instrumental benefits to INGO project performance and management. It is argued that if INGOs are to achieve their missions, this will require more ‘strategic’ forms of accountability, geared towards fundamentally changing those social, economic, and political structures that promote poverty. 相似文献
43.
44.
P. Gill C.H. Brenner J.S. Buckleton A. Carracedo M. Krawczak W.R. Mayr N. Morling M. Prinz P.M. Schneider B.S. Weir 《Forensic Science International Supplement Series》2006,160(2-3):90-101
The DNA commission of the International Society of Forensic Genetics (ISFG) was convened at the 21st congress of the International Society for Forensic Genetics held between 13 and 17 September in the Azores, Portugal. The purpose of the group was to agree on guidelines to encourage best practice that can be universally applied to assist with mixture interpretation. In addition the commission was tasked to provide guidance on low copy number (LCN) reporting. Our discussions have highlighted a significant need for continuing education and research into this area. We have attempted to present a consensus from experts but to be practical we do not claim to have conveyed a clear vision in every respect in this difficult subject. For this reason, we propose to allow a period of time for feedback and reflection by the scientific community. Then the DNA commission will meet again to consider further recommendations. 相似文献
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46.
George M. Guess 《公共行政管理与发展》1991,11(6):573-589
The failure of forestry to contribute to poverty reduction in Central America is due to public policies which inhibit its profitability. Absence of public regulation of harvesting and competing subsidies to agriculture keep forestry stumpage prices artificially low. This encourages destruction of the forest resource, which damages both the environment and the potential to reduce poverty. A comparison of Costa Rica and Honduras reveals two dissimilar approaches toward forest policy. While Costa Rica attempts to raise producer and grower stumpage prices by tax credits, soft loans and differential species fees, Honduras enforces price ceilings and uses centralized authority to control forest production and export. Both countries exhibit weaknesses in the management control cycle of programming, budgeting, implementing and evaluating their forest policies. Yet the Costa Rican approach has increased stumpage prices already, which bodes well for their forest sector. By contrast, the major beneficiary of Honduran forest policy has been COHDEFOR, the state enterprise responsible for forestry management, controlling production, and running its national system of agroforestry cooperatives. Despite greater public authority and resources than the Costa Rican forest service (DGF), the Honduran forest policy is not likely to increase producer profitability or reduce poverty in the near future. 相似文献
47.
Provincial governments in the Netherlands have only one general tax at their disposal. However, it has become an insufficient source of revenue for this level of government in the Dutch system. To increase the revenue raising capacity of the provincial governments, thirteen broad-based general tax proposals not used at the local level were examined. The objective was to find a fair and equitable tax that could easily be collected and would result in fl. 200 million in additional revenue for the provincial governments. 相似文献
48.
宁夏羊胃肠道线虫对现行驱虫药的抗药性调查 总被引:4,自引:2,他引:2
采用粪便虫卵减少试验对宁夏地区所属灵武、贺兰、盐池、吴忠、中宁、中卫、永宁和银川市郊8个县(市)的12个绵羊场、6个山羊场进行了丙硫苯咪唑和阿维菌素抗药性的随机调查。结果表明:在用丙硫苯咪唑调查的10个绵羊场和6个山羊场中,虫卵减少率在95%以下和95%的置信域下限在90%以下的有山羊场2个、绵羊场2个,证明对丙硫苯咪唑有抗药性;1个绵羊场和1个山羊场的虫卵减少率是96.3%、95.9%,但95%置信域的下限在90%以下,具有抗药性可疑;山羊群中丙硫苯咪唑的抗药性为33.3%,绵羊群为20.0%。用同样的方法调查了1个山羊场和5个绵羊场(其中有4个羊场曾执行了丙硫苯咪唑的试验),查出1个山羊场和1个绵羊场对阿维菌素具有抗药性可疑,其虫卵减少率分别为97.3%和95.5%,置信域下限在90%以下。揭示了宁夏地区羊消化道线虫对现行驱虫药的抗药状态,为今后防治提供了依据。 相似文献
49.
Michael M. Gunter 《中东政策》2007,14(1):117-123
50.
涉网犯罪在刑事案件发案中所占比例呈上升趋势,利用网络为犯罪提供各种服务的刑事案件越来越普遍.文章结合各种形式的涉网犯罪,对涉网犯罪案件利用网络寻找犯罪对象、准备犯罪工具、联络同伙、实施犯罪、销赃等情况进行仔细剖析,帮助侦查人员了解涉网犯罪,发现犯罪与网络具有的联系,为研究涉网犯罪侦查提供思路. 相似文献