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21.
采用RT-PCR方法对1株H9N2亚型禽流感病毒Ck/GS/2/99株RNA聚合酶基因PB2、PB1和PA分别进行了扩增,将其克隆到pGEM-T easy载体后进行序列测定与分析。结果表明,该株病毒的PB2、PB1和PA基因开放阅读框(ORF)分别由2280、2274和2 151个碱基组成,分别编码759、757和716个氨基酸。经同源性与系统发生树分析,该毒株RNA聚合酶基因PB2、PB1和PA与Ck/NX/4/99株的核苷酸和氨基酸同源性均在98%以上,另外这3个基因与Dk/HK/Y280/97、Sw/HK/9/98和Qu/HK/NT/28/99株的关系密切。  相似文献   
22.
中国—东盟的全面经济合作,是应经济全球化而产生的国际区域合作的又一新的成果,其“合作框架协议”是最基本的法制依据。而我国南方九省区加上香港、澳门两地的“泛珠三角区域合作”则是在一个国家之内,“一国两制”之下不同省区横向合作的机制创新,它不仅受到了国际区域经济合作创新的启示,而且顺应了整个社会区域整体发展的潮流。本文将在二者的实施框架机制方面进行一定的比较,欲为“泛珠三角区域合作”的法制建构献可替否。  相似文献   
23.
The floral development and potencies [Δ(9) -tetrahydrocannabinol (THC) contents] of cannabis plants were compared when grown indoors under high-pressure sodium lamps consuming electrical power at three densities (270, 400, and 600 W/m(2)). After a 3-week vegetative phase, plants were grown for 8 weeks, with lamps maintaining an artificial day length of 12 h. Foliar and floral yields were measured. Gas chromatography was used to measure the content of the psychoactive cannabinoid THC. Mean yields per unit of electrical power in each lighting regime ranged from 0.9 to 1.6 g/W, the highest being achieved in the lowest irradiance regime. The individual potencies of the separated leaf and flower materials were not affected by increasing irradiance. However, there was a corresponding increase in the overall potency of the aerial plant tissue. This was because of the plants in brighter conditions producing a higher proportion of floral material.  相似文献   
24.
Evaluation of cannabinoid concentrations in products from the legal cannabis market has been fraught with uncertainty. The lack of standardized testing methodology and the susceptibility of cannabinoids to degradation under certain storage conditions complicates the efforts to assess total tetrahydrocannabinol (THC) levels across wide geographic areas. There are few peer-reviewed surveys of cannabinoid concentrations in regulated products. Those that have been done have not characterized the effects of differences in analytical methodology, sample population, and storage conditions. Viridis Laboratories, which operates two cannabis safety compliance facilities in Michigan, has analyzed over 34,000 cannabis products throughout 2021 and 2022 before the sale in the regulated market. Fifteen cannabinoids in cannabis flower, concentrates, and infused products were tested using methanolic extraction and analysis by high-performance liquid chromatography with diode-array detection. Methods were validated before use, and the flower analysis procedure was certified by the Association of Analytical Collaboration. All the samples were tested before submission for sale and therefore had not undergone prolonged storage. The results are compared with those seen in other states as well as in the illicit market. Total THC levels in cannabis flower from the regulated market are significantly higher than those seen in illicit products. The distribution of cannabinoid levels is similar in flowers intended for either the medicinal or adult-use markets, with an average potency of 18%–23% of total THC. Total THC in concentrates averages up to 82%. Other cannabinoids are observed at significant levels, mostly in products specifically formulated to contain them. These results may act as a benchmark for potency levels in the regulated market.  相似文献   
25.
H9亚型禽流感病毒RT-PCR检测方法的建立   总被引:1,自引:0,他引:1  
通过分析流感数据库中123个HA序列,根据HA保守区序列设计并合成了1对引物,建立了一步法RT-PCR检测方法,预期扩增片段大小为732 bp。通过对H9亚型禽流感病毒(AIV)不同稀释度的尿囊液和棉拭子浸出液进行检测,证实病毒尿囊液的最低检出量为1×104.7EID50/mL;阳性棉拭子的最低检出量为1×102.5EID50/mL。用该方法检测H1~H15亚型AIV和鸡新城疫病毒等其他14种禽病病原,结果仅有H9亚型AIV出现特异性目的条带,而其他均未出现目的条带。脏器及咽喉、泄殖腔棉拭子样品在1∶10稀释度下,病毒分离和RT-PCR方法可以达到相同的阳性检出率。表明建立的AIV H9亚型RT-PCR方法具有较好的特异性和敏感性。  相似文献   
26.
Abstract: The University of Mississippi has a contract with the National Institute on Drug Abuse (NIDA) to carry out a variety of research activities dealing with cannabis, including the Potency Monitoring (PM) program, which provides analytical potency data on cannabis preparations confiscated in the United States. This report provides data on 46,211 samples seized and analyzed by gas chromatography‐flame ionization detection (GC‐FID) during 1993–2008. The data showed an upward trend in the mean Δ9‐tetrahydrocannabinol (Δ9‐THC) content of all confiscated cannabis preparations, which increased from 3.4% in 1993 to 8.8% in 2008. Hashish potencies did not increase consistently during this period; however, the mean yearly potency varied from 2.5–9.2% (1993–2003) to 12.0–29.3% (2004–2008). Hash oil potencies also varied considerably during this period (16.8 ± 16.3%). The increase in cannabis preparation potency is mainly due to the increase in the potency of nondomestic versus domestic samples.  相似文献   
27.
为验证siRNAs对猪繁殖与呼吸综合征病毒复制的抑制效果,构建了猪繁殖与呼吸综合征病毒NSP9基因与增强型绿色荧光蛋白基因GFP的融合表达质粒,并在Marc145细胞中进行了表达。通过RT-PCR方法扩增猪繁殖与呼吸综合征病毒NSP9基因,将其克隆入表达载体pEGFP-N1,并进行双酶切、PCR及测序鉴定。将阳性重组质粒转染Marc145细胞,检测绿色荧光蛋白的表达和NSP9基因转录水平。结果显示,经双酶切及PCR鉴定,目的基因的大小与预期相符。荧光显微镜和流式细胞仪均检测到细胞内绿色荧光蛋白的表达,荧光定量PCR检测到细胞内有NSP9基因的转录。本研究成功构建的猪繁殖与呼吸综合征病毒NSP9基因GFP融合表达质粒,为在细胞水平快速筛选有效的siRNAs提供了工具。  相似文献   
28.
为明确3株鸭源H9N2亚型禽流感病毒福建株A/Muscovy duck/Fujian/CL/1997(H9N2)(简称CL株)、A/duck/Fujian/MH/2003(H9N2)(简称MH株)和A/duck/Fujian/FQ2/2007(H9N2)(简称FQ2株)全基因组的分子特征和遗传进化情况,采用RT-PCR方法扩增这3株病毒全基因片段,并进行序列比较及遗传进化分析。结果表明,所克隆的8个基因片段均有完整的开放阅读框,其血凝素基因蛋白裂解位点的氨基酸组成为-RSSR*GLF-,为不连续的碱性氨基酸,其静脉接种指数远小于1.2,均符合低致病性AIVHA蛋白裂解位点特征;CL株和MH株的HA基因在遗传进化上属于常见的CK/BJ/1/94群系;FQ2株HA基因在遗传进化上属于DK/HK/Y280/97群系,3株H9N2亚型AIV HA基因在遗传进化上均属于经典的欧亚种系。3株H9N2亚型AIV NA基因颈部均存在缺失,CL株和MH株的NA基因在遗传进化上属于常见的CK/BJ/1/94群系,FQ2株NA基因在遗传进化上属于G1群系。CL株和MH株的其他6个基因在遗传进化上均和经典的CK/BJ/1/94一致,而FQ2株则可能是由不同流感病毒基因亚系间发生自然重排的产物。  相似文献   
29.
《国际相互影响》2012,38(3):352-364
Recent studies examining the political impact of individuals9; connections to the victims of international violence find these ties have a powerful effect on people9;s attitudes and feelings. How reliable, however, are self-reported claims of ties to a conflict9;s casualties? Using data from 9/11 and the Iraq War, I examine these claims, analyzing: 1) their influence on both public assessments of foreign policy and voting behavior, 2) whether critical demographic and political factors predict the likelihood of individuals reporting a tie to a conflict casualty, 3) the predicted, aggregate likelihood of survey respondents having connections to conflict victims, and 4) the theoretical distinction between actual vs. perceived casualty connections. The results strongly support the use of casualty connection data for understanding individuals9; responses to international violence, and encourage future applications of social network approaches to the study of war and politics.  相似文献   
30.
From a humanities course on terrorism that focuses on how terrorist ideology and acts are transformed into cultural artefacts, several pedagogical–theoretical issues have emerged: the incongruity of viewing terrorist violence as art; 9/11 as an ahistorical event; the impossibility of defining terrorism; the infiltration (trivialisation?) of terrorism into popular culture; subgenres of terrorist works, each with its own paradigm; and the iconoclastic potential of many terrorist texts and films. These issues have implications for the curricular design of terrorism courses and for the role of instructors – in academia and in the larger community.  相似文献   
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