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921.
922.
Diane?Carlson?JonesEmail author Joy?K.?Crawford 《Journal of youth and adolescence》2005,34(6):629-636
This research evaluated a dual pathway model for body dissatisfaction among adolescent boys. The study provides empirical
support for the importance of distinguishing between weight and muscularity concerns in understanding male body image. A total
of 128 boys from grades 8 and 11 completed a self-report questionnaire. Results indicated that weight and muscularity concerns
each made unique contributions to body dissatisfaction and were associated with distinct individual and peer context characteristics.
Weight concern was associated with elevated BMI and more frequent appearance conversations with friends. Muscularity concern
was significantly greater among boys who reported more frequent muscle-building conversations, had lower BMI, and were older.
The results support the importance of distinguishing between and assessing both muscularity and weight concerns in the development
of body image dissatisfaction among adolescent boys. 相似文献
923.
Johnson RD Lewis RJ Canfield DV Dubowski KM Blank CL 《Journal of forensic sciences》2005,50(3):670-675
Specimens from fatal aviation accident victims are submitted to the FAA Civil Aerospace Medical Institute for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Care must be taken when interpreting a positive ethanol result due to the potential for postmortem ethanol formation. Several indicators of postmortem ethanol formation exist; however, none are completely reliable. The consumption of ethanol has been shown to alter the concentration of two major serotonin metabolites, 5-hydroxytryptophol (5-HTOL) and 5-hydroxyindole-3-acetic acid (5-HIAA). While the 5-HTOL/5-HIAA ratio is normally very low, previous studies using living subjects have demonstrated that the urinary 5-HTOL/5-HIAA ratio is significantly elevated for 11-19 h after acute ethanol ingestion. Recently, our laboratory developed and validated an analytical method for the simultaneous determination of both 5-HTOL and 5-HIAA in forensic urine samples using a simple liquid/liquid extraction and LC/MS/MS and LC/MS/MS/MS. In this previous work a 15 pmol/nmol serotonin metabolite ratio cutoff was established in postmortem urine, below which it could be conclusively determined that no recent antemortem ethanol consumption had occurred. In the current study this newly validated analytical method was applied to five ethanol-positive aviation fatalities where the origin of the ethanol present could not previously be conclusively determined. In four of the five cases examined the detected ethanol was demonstrated to be present due to postmortem microbial formation, and not consumption, even though some indication of ethanol consumption may have been present. 相似文献
924.
Ginter JK 《Journal of forensic sciences》2005,50(6):1303-1309
The effectiveness of the original maxillary suture method for estimating age at death, introduced in 1987 by Mann and colleagues, has been tested, but their revised maxillary suture method (1991) has not been subject to similar scrutiny. The purpose of this study is to test the accuracy of the revised maxillary suture method in estimating age at death on a genetically diverse skeletal sample of 155 maxillae (96 males, 59 females, aged 26 to 100 years) of known age at death from the Department of Anatomy and Cell Biology, University of Cape Town, South Africa. Results from a prior study of the original maxillary suture method will be compared. With age category correctly estimated for 83% of this sample, the results of this study indicate that the revised method is more effective in estimating age at death than the original method. The revised method appears to perform best for older individuals and tends to underestimate age for individuals of all age groups. The results suggest that the revised method is useful as a method for age estimation when it is used conjunction with other estimators. 相似文献
925.
Elizarova MK Konareva EG Kharichkova EV Shormanov VK 《Sudebno-meditsinskaia ekspertiza》2005,48(4):23-26
The results are presented of extraction of 1-methyl-3,4-dioxybenzene, 1-methyl-2,5-dioxybenzene and 4-oxybenzene acid from aqueous solutions with hydrophobic and hydrophilic organic soluvants. It is shown that the degree of extraction depends on the nature of the extragents and pH of the aqueous phase medium. Extraction multiplicity for obtaining necessary quantities of the compounds is calculated. 相似文献
926.
Mulla A Massey KL Kalra J 《The American journal of forensic medicine and pathology》2005,26(2):146-149
The present study was conducted to investigate the differences in the vitreous humor biochemical concentrations for vitreous electrolytes and calcium in the same pair of eyes at identical postmortem interval (PMI). The vitreous humor samples were collected independently in both eyes from 48 autopsies (PMI range, 4.5-84.3 hours) with documented time of death. The samples were analyzed for potassium, sodium, chloride, and calcium using a Beckman Coulter LX20 Automated Analyzer based on ion-selective electrode methodology. There were no statistically significant between-eye differences at identical postmortem interval. A significantly high correlation was observed between paired potassium concentrations of both the eyes. A highly significant linear correlation was observed between the individual eye and mean potassium concentrations of both the eyes with postmortem interval. The observed differences were not significantly correlated with postmortem interval. The results demonstrated that the between-eye differences for vitreous electrolytes and calcium are insignificant. Therefore, the utility of vitreous biochemistry, particularly potassium in postmortem interval estimation and other forensic applications, cannot be questioned solely on the basis of these differences. 相似文献
927.
The consumption of Delta9-tetrahydrocannabinol (THC) as cannabis has been shown to result in impaired and culpable driving. Testing drivers for the presence of THC in blood is problematic as THC and its metabolites may remain in the blood for several days following its consumption, even though the drug may no longer have an influence on driving performance. In the present study, the aim was to assess whether performance on the standardised field sobriety tests (SFSTs) provides a sensitive measure of impaired driving behaviour following the consumption of THC. In a repeated measures design, 40 participants consumed cigarettes that contained either 0% THC (placebo), 1.74% THC (low dose) or 2.93% THC (high dose). For each condition, after smoking a cigarette, participants performed the SFSTs on three occasions (5, 55 and 105 min after the smoking procedure had been completed) as well as a simulated driving test on two occasions (30 and 80 min after the smoking procedure had been completed). The results revealed that driving performance was not significantly impaired 30 min after the consumption of THC but was significantly impaired 80 min after the consumption of THC in both the low and high dose conditions. The percentage of participants whose driving performance was correctly classified as either impaired or not impaired based on the SFSTs ranged between 65.8 and 76.3%, across the two THC conditions. The results suggest that performance on the SFSTs provides a moderate predictor of driving impairment following the consumption of THC and as such, the SFSTs may provide an appropriate screening tool for authorities that wish to assess the driving capabilities of individuals suspected of being under the influence of a drug other than alcohol. 相似文献
928.
929.
The mathematical and anatomical methods of estimating living stature from long limb bones are discussed. In forensic cases, when one has a nearly complete skeleton, the anatomical method is preferable to the mathematical method. The anatomical method may also be used to derive stature estimation equations in samples where living statures or cadaver lengths are unavailable, such as some dissection hall and museum collections. 相似文献
930.
K Simpson 《The Medico-legal journal》1968,36(2):Suppl 4:58-Suppl 4:71