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221.
This study was designed to compare the qualitative results and concentrations of methamphetamine (MA) and its metabolite amphetamine (AP) in head hair and hair collected from different parts of the body (axillae and pubis). Hair from subjects (N = 14) suspected MA users was simultaneously collected. Hair preparation involved washing step, fine cutting, overnight extraction, derivatization by the trifluoroacetic anhydride, and gas chromatography/mass spectrometry (GC/MS) using selective ion monitoring. In this study, we found a good correlation of the qualitative results for MA between head hair and hair on other parts of the body, but there were some differences in concentrations of MA and AP. Namely, the concentrations of MA and AP were higher in axillary and pubic hair than in head hair.  相似文献   
222.
Sequence polymorphism of the mitochondrial DNA (mtDNA) control region, hypervariable regions HVR I, HVR II and HVR III, from 51 unrelated China Han (Yan Bian area) were determined by PCR amplification and cycle sequencing.  相似文献   
223.
This study reviewed the public notification policy of sexual offenders against minors in South Korea as compared to community notification programs in the United States. The study then examined the policy's impact on increasing the general public's awareness of such sexual crimes. This is based on the assumption that heightening public awareness can be a starting point in combating such crimes. Results of the data, drawn from a sample of 1,409 Koreans across the nation, showed that the notification policy enhanced public awareness. Factors related to this increase in awareness were people's concern about or familiarity with the policy and people's experience in identifying the existence of known sexual offenders in their communities. Based on the results of this study, strategies for enhancing public awareness of sexual crimes on minors were formulated. The need to develop treatment programs for sexual offenders was likewise highlighted.  相似文献   
224.
The prevalence and age distribution of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) in hair samples by gas chromatography/mass spectrometry (GC/MS) were studied. The recoveries obtained from hair were 97% and 99% for MDMA and MDA, respectively. The inter- and intra-assay precision and accuracy were determined. Out of 791 hair samples, 44 (5.6 %) contained MDMA and/or MDA. Out of these 44 subjects, urinalyses from 35 were negative for both MDMA and MDA, while only 9 were positive. We also evaluated concentrations of MDMA and MDA, and the metabolite-to-parent drug ratios. This study showed that the abuse of MDMA or MDA was found principally among young adults and male abusers. We found the epidemiology of ecstasy users in Korea between March 2002 and April 2003.  相似文献   
225.
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed.  相似文献   
226.
The recent House of Lords decision in Quintavalle v Human Fertilisation and Embryology Authority has raised difficult and complex issues regarding the extent to which embryo selection and reproductive technology can be used as a means of rectifying genetic disorders and treating critically ill children. This comment outlines the facts of Quintavalle and explores how the House of Lords approached the legal, ethical and policy issues that arose out of the Human Fertilisation and Embryology Authority's (UK) decision to allow reproductive and embryo technology to be used to produce a 'saviour sibling' whose tissue could be used to save the life of a critically ill child. Particular attention will be given to the implications of the decision in Quintavalle for Australian family and medical law and policy. As part of this focus, the comment explores the current Australian legislative and policy framework regarding the use of genetic and reproductive technology as a mechanism through which to assist critically ill siblings. It is argued that the present Australian framework would appear to impose significant limits on the medical uses of genetic technology and, in this context, would seem to reflect many of the principles that were articulated by the House of Lords in Quintavalle.  相似文献   
227.
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.  相似文献   
228.
The purpose of this study is to understand why some battered mothers physically abuse their children. Mothers who were battered and physically abused their children (the co-occurrence group) were compared with mothers who were neither battered nor physically abused, who were only battered, and who only abused (N = 184). The mothers in the co-occurrence group were more likely than the mothers who did not physically abuse their children to have been severely assaulted by their own mothers as children, have had poorer quality relationships with and receive less support from their mothers, have more stressors, and have known their partners for less time. These differences were not found between the mothers in the co-occurrence and abuse-only groups. In the multivariate analysis, having been assaulted by one's own mother as a child--not being battered by one's partner--was the most potent predictor for whether a mother physically abused her child.  相似文献   
229.
The Y-PLEX 12 system, developed for use in human identification, enables simultaneous amplification of eleven polymorphic short tandem repeat (STR) loci, namely DYS392, DYS390, DYS385 a/b, DYS393, DYS389I, DYS391, DYS389II, DYS 19, DYS439 and DYS438, residing on the Y chromosome and Amelogenin. Amelogenin provides results for gender identification and serves as internal control for PCR. The validation studies were performed according to the DNA Advisory Board's (DAB) Quality Assurance Standards. The minimal sensitivity of the Y-PLEX 12 system was 0.1 ng of male DNA. The mean stutter values ranged between 3.76-15.72%. A full male profile was observed in mixture samples containing 0.5 ng of male DNA and up to 400 ng of female DNA. Amelogenin did not adversely affect the amplification of Y-STRs in mixture samples containing male and female DNA. The primers for the Y-STR loci present in Y-PLEX 12 are specific for human DNA and some higher primates. None of the primate samples tested provided a complete profile at all 11 Y-STR loci amplified with the Y-PLEX 12 system. Y-PLEX 12 is a sensitive, valid, reliable, and robust multiplex system for forensic analysis, and it can be used in human forensic and male lineage identification cases.  相似文献   
230.
This study examined effects of clothing cues on children's identification accuracy from lineups. Four- to 14-year-olds (n = 228) saw 12 video clips of individuals, each wearing a distinctly colored shirt. After watching each clip children were presented with a target-present or target-absent photo lineup. Three clothing conditions were included. In 2 conditions all lineup members wore the same colored shirt; in the third, biased condition, the shirt color of only one individual matched that seen in the preceding clip (the target in target-present trials and the replacement in target-absent trials). Correct identifications of the target in target-present trials were most frequent in the biased condition, whereas in target-absent trials the biased condition led to more false identifications of the target replacement. Older children were more accurate than younger children, both in choosing the target from target-present lineups and rejecting target-absent lineups. These findings suggest that a simple clothing cue such as shirt color can have a significant impact on children's lineup identification accuracy.  相似文献   
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