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排序方式: 共有543条查询结果,搜索用时 15 毫秒
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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
484.
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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486.
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
489.
Denise B. Kandel Ronald C. Kessler Rebecca Z. Margulies 《Journal of youth and adolescence》1978,7(1):13-40
The social psychological antecedents of entry into three sequential stages of adolescent drug use, hard liquor, marihuana, and other illicit drugs, are examined in a cohort of high school students in which the population at risk for initiation into each stage could be clearly specified. The analyses are based on a two-wave panel sample of New York State public secondary students and subsamples of matched adolescent-parent and adolescent-best schoolfriend dyads. Each of four clusters of predictor variables, parental influences, peer influences, adolescent involvement in various behaviors, and adolescent beliefs and values, and single predictors within each cluster assume differential importance for each stage of drug behavior. Prior involvement in a variety of activities, such as minor delinquency and use of cigarettes, beer, and wine are most important for hard liquor use. Adolescents' beliefs and values favorable to the use of marihuana and association with marihuana-using peers are the strongest predictors of initiation into marihuana. Poor relations with parents, feelings of depression, and exposure to drug-using peers are most important for initiation into illicit drugs other than marihuana.This research is supported by Grant DA-00064 from the National Institute on Drug Abuse and by the Center for Socio-Cultural Research on Drug Use of Columbia University.Revised version of a paper presented at the Conference on Strategies of Longitudinal Research on Drug Use, San Juan, Puerto Rico, April 1976. Authors' names are listed alphabetically.Received Ph.D. in sociology from Columbia University in 1960. Current research interests are adolescent socialization, longitudinal approaches to the study of human behavior and psychopathology, and processes of interpersonal influence.Received Ph.D. in sociology from New York University in 1975. Major interest is quantitative sociology.Received Ph.D. in sociology from Columbia University in 1975. Current research interests include adolescent socialization and deviant behavior. 相似文献
490.
Genetic variation and relationships at five STR loci in five distinct ethnic groups in China 总被引:3,自引:0,他引:3
Lin Z Ohshima T Gao S Kondo T Takayasu T Sato Y Sun K 《Forensic science international》2000,112(2-3):179-189
Five short tandem repeat (STR) systems of TH01, vWA, LPL, F13B and FES/FPS were investigated in five ethnic groups living in China (Tujia, Miao, Bai, Chaoxian and Han). All five loci did not deviate from the Hardy-Weinberg equilibrium (P>0.05). At the five loci of each ethnic group, the observed heterozygosity, the mean exclusion chance (MEC), and the power of discrimination (PD) ranged from 0.42 to 0.86, from 0.20 to 0.66 and from 0.61 to 0.95, respectively. For the five ethnic groups, the combined MEC and combined PD were >0. 9360 and >0.9998, respectively, suggesting that combinations of these five systems are feasible for DNA typing in forensic investigations such as personal identification or paternity testing. Furthermore, the allelic frequencies at the five loci suggested that these five ethnic groups were distinctly different communities. Judging from the phylogenetic tree constructed based on the genetic distance among the five ethnic groups, Han, Chaoxian and Tujia were involved in an identical cluster, and Miao and Bai in another. These findings indicate that each of the five groups examined is not only a distinct community, but also has a relationship with each of the others. 相似文献