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By substituting the saturated vapour phase tension of the pure normal hydrocarbons described by the Clausius-Clapeyron law into the accepted expression of the specific retention volume (Vg,T), a theoretically coherent and relatively simple mathematical evidence of the elution behaviour of the homologous members has been deduced. It gives exponential retention time dependence on carbon number for isothermal, and nearly equidistant (i.e., approximately linear retention-time dependence on carbon number) elution for linear temperature programmed gas chromatographic runs. The final equations are in close correlation with the experimental results. Special emphasis is placed on the fact that a good approximation—not strict physical laws—have been found. 相似文献
13.
Â. C. Volpini M. J. Marques S. Lopes dos Santos G. L. Machado-Coelho W. Mayrink A. J. Romanha 《Clinical microbiology and infection》2006,12(8):815-818
This study examined the ability of PCR to amplify Leishmania DNA, stored on Giemsa-stained slides, from American cutaneous leishmaniasis (ACL) patients. In total, 475 slides stored for up to 36 years were obtained from an outpatient clinic in a Brazilian ACL-endemic region, and Leishmania DNA was amplified from 395 (83.2%) of the DNA samples using primers specific for the minicircle kinetoplast DNA. Restriction fragment length polymorphism analysis of these amplicons demonstrated that Leishmania (Viannia) braziliensis was the only species present in these samples. The results demonstrated that archived Giemsa-stained slides can provide a Leishmania DNA source for performing clinical and epidemiological studies of leishmaniasis. 相似文献
14.
A. G. G. Lødeng C. Ahlén H. Lysvand L. H. Mandal O. J. Iversen 《Clinical microbiology and infection》2006,12(8):761-768
This report describes a new PCR-based assay for the detection of Pseudomonas aeruginosa genotype D in occupational saturation diving systems in the North Sea. This genotype has persisted in these systems for 11 years (1993-2003) and represents 18% of isolates from infections analysed during this period. The new PCR assay was based on sequences obtained after randomly amplified polymorphic DNA (RAPD)-PCR analysis of a group of isolates related to diving that had been identified previously by pulsed-field gel electrophoresis (PFGE). The primer set for the D genotype targets a gene that codes for a hypothetical class 4 protein in the P. aeruginosa PAO1 genome. A primer set able to detect P. aeruginosa at the species level was also designed, based on the 23S-5S rDNA spacer region. The two assays produced 382-bp and 192-bp amplicons, respectively. The PCR assay was evaluated by analysing 100 P. aeruginosa isolates related to diving, representing 28 PFGE genotypes, and 38 clinical and community P. aeruginosa isolates and strains from other species. The assay identified all of the genotype D isolates tested. Two additional diving-relevant genotypes (TP2 and TP27) were also identified, as well as three isolates of non-diving origin. It was concluded that the new PCR assay is a useful tool for early detection and prevention of infections with the D genotype. 相似文献
15.
川产贝母种质资源遗传多样性的ISSR分析 总被引:1,自引:0,他引:1
目的:为阐明川产贝母资源间亲缘关系提供更多证据.方法:利用ISSR分子标记技术对川产10个种1变种共19份材料进行分析,采用NTSYS软件计算材料间相似系数,并用UPGMA法构建了系统树.结果:从35个ISSR引物中共筛选出11个多态性明显、反应稳定的引物,在19份供试材料DNA中共扩增出179条谱带,其中多态性条带163条,占86.8%.材料间ISSR标记遗传相似性系数(GS)在0.569~0.855.聚类分析结果显示,所有供试材料均可区分开,并聚为4组.第1组包括川贝母、甘肃贝母、长腺贝母和短丝贝母,第Ⅱ组由暗紫贝母和浓蜜贝母组成,槽鳞贝母、浙贝母、瓦布贝母和梭砂贝母聚为第Ⅲ组,湖北贝母单独为第Ⅳ组.试验结果还表明,来源于同一地区的多数川产贝母材料可分别聚在一起.结论:ISSR标记适用于川产贝母资源的遗传多样性研究,但药典收载的川贝母药材的4种基原植物种间及其与其他川产贝母属各物种间尚不能仅通过采用ISSR标记技术进行分子鉴定.此外,ISSR聚类结果同川产贝母资源的地理分布有一定关系. 相似文献
16.
Andrea Lamont-Mills Steven A. Christensen 《Journal of Science and Medicine in Sport》2006,9(6):472-478
This study looked at the relationship between athletic identity and three levels of sport participation (elite, recreational, non-participation). Athletic identity was measured using the Athletic Identity Measurement Scale (AIMS) with participants being compared on the total AIMS score and scores on its three factors (social identity, exclusivity, negative affectivity). Results indicated that the male non-participation group scored lower on all three factors and the total AIMS when compared to the two athlete groups. The male elite and recreational groups did not differ on exclusivity and negative affectivity but did differ on the total AIMS and social identity, with elite scoring higher than recreational. For female participants, the non-participation group again scored lower on all three factors and the total AIMS when compared to the two athlete groups. The female elite and recreational groups did not differ on negative affectivity but did differ on the total AIMS, social identity, and exclusivity, with elite scoring higher than recreational. Findings suggest that to assume sport is only important to elite athletes ignores the role that sport may play for less talented sport participants. Whilst not seeing themselves as athletes per se, it is suggested that participation in sport may still impact upon the self-perceptions of recreational sport participants. Therefore, threats to participation may result in similar negative consequences for both elite athletes and recreational sport participants. 相似文献
17.
上海城乡儿童智力发育调查 总被引:3,自引:0,他引:3
为探索着力低下早期发现的途径和方法,对上海城乡4546名0~12岁)儿童进行了智力发育测查。首先用DDST或绘人测验进行智力筛查,筛查阳性者按不同年龄用儿——心量表、WPPSI或WISC—R进行测试。DQ或IQ低于70者以婴幼儿一初中生社会生活量表进行社会适应能力评估。测查结果共发现智力低下42例,占调查儿童总数的9.24%。城乡相比,农村智力低下现患率(16.13‰)明显高于城市(4.19‰),P<0.01。从性别来分,男孩现患率(11.36‰)高于女孩(6.91‰)。智力低下患病率有随年龄增加而上升的趋势。因素分析与配对研究显示智力低下与父母文化素质有密切关系,父母文化程度小学以下者其子女智力低下患病率高。智力低下的发生还与高危因素有关。 相似文献
18.
喉症丸鉴定方法的研究 总被引:1,自引:1,他引:0
对不同批号喉症丸的二阶导数紫外谱线组图谱进行了测绘分析,发现不同批号的喉症丸其四溶剂二阶导数紫外吸收光谱特征数据,λmax或λsh具有很好的重现性,其分辨率高,特征性强,因此,以二阶导数紫外谱线组法控制喉症丸质量,鉴别喉症丸真伪优劣具有良好的重现性和准确性。 相似文献
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20.
报告了从辽宁省部分地区腹泻和感染标本中检出的成团肠杆菌、非脱羧勒克氏菌、克吕沃尔氏菌、彭氏变形菌、霍堆氏肠杆菌的分离、鉴定,药敏试验及致病性研究结果.部分菌株可引起动物、生物模型病变,证明有致病力.与人的腹泻和感染有关.致病性研究中,溶血性阳性率最高,依次为乳鼠灌胃,HeP—2细胞、Vero细胞病变,兔肠袢结扎.豚鼠角膜侵袭试验无阳性.药敏试验证实,5组细菌抗药谱已很广,临床可用的敏感药物不多,一旦发生感染,治疗将十分困难. 相似文献