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501.
The study was to eliminate interference from ephedrine in the analysis of methamphetamine. The extraction procedure for methamphetamine was modified to include an oxidation step (2 ml urine specimen was treated with 0.5 ml of 1 mol/L phosphate buffer (pH 6.8) and 0.5 ml 0.3 mol/L sodium periodate). Results showed that ephedrine could be oxidized in the presence of periodate ions into smaller fragments while leaving methamphetamine intact. It is recommended that specimens be treated with sodium periodate prior to extraction in order to eliminate any interference caused by ephedrine. 相似文献
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Population genetic study of the complicated STR locus-FGA was performed by the method of PCR in Han population samples. A total of 21 different alleles including 7 interalleles and 63 different genotypes were observed in 349 unrelated individuals. The observed genotype discrimination showed no significant deviation from Hardy-Weinberg equilibrium and 51 family studies showed no mutation. According to the results obtained in this study(DP = 0.9612, PE = 0.7007, PIC = 0.8333), this system can be used as an useful means in forensic identification of both criminal and paternity case. 相似文献
506.
Allele and genotype frequencies of four short tandem repeat loci were determined in a population sample from east China by using PCR and fluorescence techniques. After denaturing PAGE, 9 alleles were identified for CSF1PO, 8 alleles for TPOX, and 7 alleles for TH01. All loci met Hardy-Weinberg expectations. In addition, the theoretical values of these loci for paternity and forensic casework were evaluated. 相似文献
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尿样中海洛因代谢物的测定及海洛因滥用的确认 总被引:5,自引:1,他引:4
用SPE-GC-NPD法建立了尿样中吗啡、6-单乙酰吗啡及可待因的定性分析方法,适用于海洛因滥用者的尿样分析。尿样中吗啡及可待因的最小检测限均为50ng/ml。方法的相对标准偏差分别为:吗啡11.3%(n=5),可待因14.2%(n=5)。方法简便、灵敏、快速,15min可完成一例尿样的分析。研究了服用含可待因成分的复方甘草合剂后,尿样中的吗啡及可待因的峰面积比为0.457±0.197(P=99%);统计了40例明确滥用海洛因尿液的分析结果,吗啡与可待因的峰面积比为3.46±0.894,P=99%。可作为判断海洛因滥用的依据。同时与免疫板法比较,附55例免疫板法阳性尿样的分析结果 相似文献
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Adolescents' Commitment to Developing Talent: The Role of Peers in Continuing Motivation for Sports and the Arts 总被引:2,自引:0,他引:2
Patrick Helen Ryan Allison M. Alfeld-Liro Corinne Fredricks Jennifer A. Hruda Ludmila Z. Eccles Jacquelynne S. 《Journal of youth and adolescence》1999,28(6):741-763
The role of peer relationships in supporting or hindering adolescents' talent development has received little research attention, despite the importance of peers in adolescents' lives. We conducted semi-structured in-depth interviews with 41 adolescents talented in sports or the arts, and their parents, to investigate (a) the role of peer relationships in adolescents' continued involvement in their talent activities, (b) possible differences in this role by activity domain, and (c) possible gender differences. Thematic analysis indicated that peers typically played a positive function in supporting the continued involvement of talented adolescents in their talent activities. There were differences in opportunities for peer relationships and social satisfaction between in-school and out-of school activities, but not between activity domains. Both males and females mentioned equally social benefits of such involvement. However, females mentioned receiving negative peer attention more frequently than males, and more often cited social dissatisfaction as a significant contributor to decreased involvement or quitting. 相似文献