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51.
The differences between male and female adolescents' emotional reactions to their most recent occasion of sexual intercourse were examined. The sample included 932 sexually active Australian secondary school students who completed a self-report questionnaire concerning their sexual behavior. The majority of young people reported that they felt happy or good following their most recent occasion of sex. Females were more likely than males to report negative emotions such as feeling bad and used, but there was no difference between the percentage of males and the percentage of females who reported feeling guilty. Girls were more likely to feel bad, used, or guilty last time if they were drunk/high or had sex with someone who was not a steady partner. Boys who had sex with someone other than a steady partner last time were more likely to feel guilty. Peer and parental influences were also associated with feelings of guilt. Girls who were more confident that they could talk to one of their parents/guardians about sex, and boys who believed that most of their peers were sexually active, were less likely to have felt guilty.Received B.A. (Hons) from University of Queensland. Research interests include adolescents mental and sexual health.Received B.A.(Hons) from University of Queensland. Interested in the areas of sex roles and sexual behavior among adolescents.Received Ph.D. from Murdoch University. Research interests include population studies of sexual behavior and mental health.Received M.B.B.S., M.D. from University of Sydney. Research interests include adolescent health, psychological response in disasters, coping with grief and loss and living with HIV/AIDS.  相似文献   
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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   
54.
One hundred thirty-four unrelated Northeast Brazilian individuals were typed for the HPRTB, F13B, and LPL short tandem repeats (STRs). DNA was amplified by specific primers and identified by silver staining of polyacrylamide gels. The allelic frequencies of these loci were in agreement with Hardy-Weinberg proportions. The most frequent alleles were HPRTB*13, F13B*10, LPL*10. The combined probability of paternity and the discrimination power of these 3 STRs were high, permitting their utilization for forensic science purposes.  相似文献   
55.
A 77-year-old man was found in his flat with a shot to the right temple. In spite of hospital treatment he died from the head injury the next day. The weapon at the scene used for committing the suicide was a pistol, make Kaba Special (calibre 6.35 mm). At autopsy, the right temporal region showed a surgically treated, originally stellate gunshot entrance wound with a powder cavity. Close to this penetrating gunshot wound there were 3 parallel graze shot injuries of the scalp. The autopsy findings were consistent with the assumption that all the shots had been fired by the victim himself with suicidal intent. The injury pattern is presented and discussed in relation to the results of the technical investigation of the weapon and the findings at the scene.  相似文献   
56.
In a fire tragedy in Manila in December 1998, one of the worst tragic incidents which resulted in the reported death of 23 children, identity could not be established initially resulting in the burial of still unidentified bodies. Underscoring the importance of identifying each of the human remains, the bodies were exhumed 3 months after the tragedy. We describe here our work, which was the first national case handled by local laboratories wherein conventional and molecular-based techniques were successfully applied in forensic identification. The study reports analysis of DNA obtained from skeletal remains exposed to conditions of burning, burial, and exhumation. DNA typing methods using autosomal and Y-chromosomal short tandem repeat (Y-STR) markers reinforced postmortem examinations using conventional identification techniques. The strategy resulted in the identification of 18 out of the 21 human remains analyzed, overcoming challenges encountered due to the absence of established procedures for the recovery of mass disaster remains. There was incomplete antemortem information to match the postmortem data obtained from the remains of 3 female child victims. Two victims were readily identified due to the availability of antemortem tissues. In the absence of this biologic material, parentage testing was performed using reference blood samples collected from parents and relatives. Data on patrilineal lineage based on common Y-STR haplotypes augmented autosomal DNA typing, particularly in deficiency cases.  相似文献   
57.
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   
58.
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   
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The captive bolt pistol is an atypical firearm exclusively produced and used for butchery of breeding animals, but in some rare cases, it has been used as a lethal weapon for committing suicide by butchers, breeders and other people who have access to such weapons during their professional activities. This study describes the suicide committed by a butcher in the province of Udine (N. Italy) in 2001 who shot himself with his own captive bolt pistol that produced in the right temporal region a circular wound and a bone lesion of the temporal squama with a groove involving the frontal lobe; he died five days later of the fatal consequences of the meningo-encephalic lesions. The medico-legal issues implicated in this case, seen in the light of the data reported in the international literature, illustrate the difficulties faced when diagnosing these types of lesions, bearing in mind their rarity and peculiar nature, and introduce elements of differential diagnosis regarding lesions produced by similar weapons that lead to ascertainment of the event as accidental, suicidal, or homicidal.  相似文献   
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