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21.
Appraisals about the implications of stressful events that are evaluated as involving a threat to self (negative self-evaluation, negative evaluation from others, rejection by others) have been shown to place youth at risk for the development of mental health problems. This longitudinal study tested a protective-stabilizing interactive model, in which high maternal acceptance was predicted to mitigate the prospective relation between threat to self appraisals and change in adolescents’ mental health problems six months later. Participants were 89 adolescents from divorced families ages 10–12 and residential mothers. Adolescents reported on threat to self appraisals from the most stressful event experienced in the past month. Mothers and youth reported on maternal acceptance and mental health problems. Multiple regression analyses provided support for the protective effects of maternal acceptance on adolescents’ mental health problems. Intervention implications are discussed. Ana Brown is a pre-doctoral fellow in prevention research (NIMH 2 T32 MH18387–19) and doctoral student in the Department of Psychology at Arizona State University, Tempe, AZ. Research interests include the study of children’s appraisals and responses to stressful events in the prevention of mental health problems. Sharlene Wolchik is a clinical psychologist and professor in the Department of Psychology at Arizona State University, Tempe, AZ. Her research focuses on identifying risk and protective factors for children whose parents have divorced. She also has designed and evaluated the efficacy of preventive interventions for children from divorced families and children who have experienced parental bereavement. Jenn-Yun Tein is a research associate professor and Co-Director of the Research Methodology Core of the Prevention Research Center at Arizona State University, Tempe, AZ. Her research interests include analyses of mediation and moderation of preventive interventions as well as applications of methodology and statistics in prevention research. Irwin Sandler is a Regents’ Professor in the Department of Psychology and Director of the Prevention Research Center at Arizona State University, Tempe, AZ. His research interests focus on understanding resilience for children exposed to stress and on the development, evaluation and dissemination of programs to promote resilience and prevent mental health problems for children in stress.  相似文献   
22.
Gene and genotype frequencies in relation to the D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S820 loci were determined in a sample of 290 unrelated individuals (204 Caucasians and 86 mulattoes) living in the city of S?o Paulo, Brazil. The sex test Amelogenin was also performed in all subjects from our sample, revealing the expected sex in all instances. Allele frequency data obtained from the analysis of these samples were in the usual range of other population groups with similar racial background. In the sample of Caucasian individuals, panmictic proportions were ruled out in relation to TPOX and CSF1PO loci, but only in the latter was the overall frequency of heterozygotes significantly less than expected. In the sample of mulattoes, Hardy-Weinberg proportions were rejected in relation to FGA and CSF1PO loci, but in no instance were the overall numbers of heterozygotes different from the corresponding expected ones under panmixia. Taking into account all this and also the number of tests performed, the degree of genetic heterogeneity of Brazilian populations, and the critical level reached by the significant results (1% < alpha<5%), the departures from panmixia here observed can be considered to be negligible in altering significantly biologic relationship odds calculated under the assumption of random matings.  相似文献   
23.
A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit.  相似文献   
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Nine Y-STR loci from the "minimal haplotype" included in Y-STR Haplotype Reference Databases (YHRD) together with eight additional Y-STRs (DYS437, DYS438, DYS439, DYS460, DYS461, GATA C4, GATA H4 and GATA A10) were analyzed in a sample of 101 males from Equatorial Guinea living in Madrid. Haplotype and allelic frequencies were calculated and genetic diversities were estimated for each genetic system as well as for the whole haplotype. An unexpected high frequency (6%) of intermediate alleles (13.2 and 14.2) was found in DYS385. For DYS19, two alleles were found in one sample. Another sample failed to amplify with DYS393 primers using either PowerPlex Y System (Promega Corporation) or the Y-PLEXtrade mark 12 (Reliagene, New Orleans, LA) commercial kits. Comparison between Equatorial Guinea and another African population (Mozambique; South East Coast) revealed a significant pairwise Phi(st) value between them (Phi(st)=0.03309; P=0.00000).  相似文献   
27.
The 11 Y-chromosomal short tandem repeats (STRs) included in the Promega Corporation PowerPlex Y System (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438 and DYS439) were typed in three ethnic groups ("Andalusians", Berber and Arab) and one cosmopolitan population (Tunis) from Tunisia, summing up 247 individuals, and 139 different haplotypes. Focusing the analysis on the seven Y-STRs of the YHRD Minimal Haplotype Core (DYS385 excepted), "Andalusians" showed no differences from the Cosmopolitan and the Arab samples previously published (our Arab sample presented an extremely low haplotype diversity), but were different from the Berbers. The Berbers from Tunisia were not different from those from Morocco.  相似文献   
28.
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.  相似文献   
29.
Risk factors associated with the likelihood of being sexually victimized by a stranger or friend/acquaintance since being on the street was examined among 372 homeless and runaway youth. Young people were interviewed on the streets and in shelters by outreach workers using a systematic sampling strategy. Youth who engaged in more high-risk behaviors were expected to be at greater risk for sexual victimization by both known and unknown assailants. Results indicated that for females, running from home for the first time at an earlier age was associated with sexual victimization by both a stranger and friend/acquaintance. However, engaging in deviant subsistence strategies, survival sex, and grooming predicted being sexually victimized by a friend/acquaintance. For males, survival sex and grooming predicted stranger sexual victimization, whereas sexual orientation was associated with sexual victimization by a friend/acquaintance. Overall, 35% of the sample had been sexually victimized.  相似文献   
30.
Survival analysis: A survey   总被引:1,自引:0,他引:1  
This paper is a survey of statistical methods used to analyze the length of time until a specified event occurs. These models have often been used to analyze the survival times (i.e., time until death) of medical patients, and so the term survival analysis is natural. In criminology, the main application of these models has been to analyze the time until recidivism, but many other applications are possible. The paper summarizes the statistical literature on survival analysis, and describes its applications in criminology. The methods are illustrated by an application to the prediction of time until recidivism for a sample of North Carolina prison releasees.  相似文献   
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