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751.
Headspace gas chromatography was used to determine the concentration of ethanol and methanol in blood samples from 519 individuals suspected of drinking and driving in Sweden where the legal alcohol limit is 0.50 mg/g in whole blood (11 mmol/l). The concentration of ethanol in blood ranged from 0.01 to 3.52 mg/g with a mean of 1.83 +/- 0.82 mg/g (+/- S.D.). The frequency distribution was symmetrical about the mean but deviated from normality. A plot of the same data on normal probability paper indicated that it might be composed of two subpopulations (bimodal). The concentration of methanol in the same blood specimens ranged from 1 to 23 mg/l with a mean of 7.3 +/- 3.6 mg/l (+/- S.D.) and this distribution was markedly skew (+). The concentration of ethanol (x) and methanol (y) were positively correlated (r = 0.47, P less than 0.001) and implies that 22% (r2) of the variance in blood-methanol can be attributed to its linear regression on blood-ethanol. The regression equation was y = 3.6 + 2.1 x and the standard error estimate was 0.32 mg/l. This large scatter precludes making reliable estimates of blood-methanol concentration from measurements of blood-ethanol concentration and the regression equation. But higher blood-methanol concentrations are definitely associated with higher blood-ethanol in this sample of Swedish drinking drivers. Frequent exposure to methanol and its toxic products of metabolism, formaldehyde and formic acid, might constitute an additional health risk associated with heavy drinking in predisposed individuals. The determination of methanol in blood of drinking drivers in addition to ethanol could indicate long-standing ethanol intoxication and therefore potential problem drinkers or alcoholics. 相似文献
752.
A report is given of two young people who died after intake of dextromethorphan, one by suicide and the other for uncertain reasons. To our knowledge this is the first reported fatal intoxications with this drug. 相似文献
753.
T Karlsmark H K Thomsen L Danielsen O Aalund O Nielsen K G Nielsen I K Genefke 《Forensic science international》1988,39(2):175-188
In order to establish pathological evidence in dermis for distinguishing between sequelae of electrical torture and those of other superficial injuries, the skin of eleven fully anaesthetized Danish Landrace pigs have been exposed to heat and electrical energy from either 50 Hz alternating current (a.c.) or direct current (d.c.) via 12 mm large contact knobs or via a pointed 0.5 mm large electrode (only 50 Hz a.c.). The lesions have been examined from 1 to 126 days after the injury. While heat lesions exposed to energy lower than 60 joule only gave minor changes, heat lesions exposed to more than 60 joule showed changes in both collagen fibres (basophilic or eosinophilic fibres without any birefringence or coarse cross-striation in polarized light, respectively) and dermal cells (granular cytoplasm). Areas exposed to 50 Hz a.c. via 0.5 mm. electrode showed basophilic collagen fibres and in a few biopsies on day 7 calcium salts on collagen fibres. Using 12 mm large electrodes the changes were minor, but basophilic and eosinophilic collagen fibres with no birefringence or with fine/coarse cross-striation respectively were seen. Even cells with 'vesicular nuclei' were seen on day 1 and 2 after the injury. The changes in the anode area showed resemblance to that of heat lesions (basophilic collagen fibres). Eosinophilic collagen fibres with fine densely spaced cross-striation in polarized light and 'vesicular nuclei' as well as collagen fibres with calcium salts were seen in the cathode lesions. It is concluded that the dermal changes in the cathode area are specific for electrical injury from day 1 to 14. However, earlier studies have demonstrated dermal changes specific for electrical injury at day 0 and the presence of calcified collagen fibres up to 2 months after injury. The dermal changes in anode lesions were non specific and could not be differentiated from those found in heat lesions. Alternating current lesions (50 Hz) were specific from day 1 to day 7, when the pointed electrode was used, but only in a few days when the energy was transferred via the 12-mm electrodes. 相似文献
754.
The polymorphism of the human vitamin D binding protein (Gc system) was investigated in a total of 149 sera from unrelated healthy Egyptians residing in Tanta City, Gharbiya Governorate, Nile Delta of Egypt, using isoelectric focusing (IEF) in thin-layer polyacrylamide gel followed by immunoblotting. The estimated gene frequencies were Gc1s = 0.540, Gc1f = 0.242 and Gc2 = 0.218. 相似文献
755.
Nicole A. Anderson Amy M. Bohnert Amy Governale 《Journal of youth and adolescence》2018,47(8):1697-1711
Research examining factors that predict youth’s involvement in organized activities is very limited, despite associations with positive outcomes. Using data from 1043 youth (49% female; 46.4% Hispanic, 35.4% African American, 14.0% Caucasian, and 4.2% other) from the Project on Human Development in Chicago Neighborhoods, this study examined how characteristics of parents (supervision, warmth) and neighborhoods (perceived neighborhood safety and collective efficacy) predict patterns of adolescents’ involvement in organized activities concurrently (i.e., intensity) and longitudinally (i.e., type and breadth). Parental supervision predicted adolescents’ participation in organized activities across multiple waves. Neighborhood violence was positively associated with concurrent participation in organized activities after controlling for socioeconomic status (SES), whereas higher neighborhood collective efficacy predicted greater breadth in organized activity participation across time. These findings have important implications regarding how to attract and sustain organized activity participation for low-income, urban youth. 相似文献
756.
Sevgi Bayram Özdemir Shuyan Sun Liliia Korol Metin Özdemir Håkan Stattin 《Journal of youth and adolescence》2018,47(6):1151-1163
Research on ethnic victimization to date has done little to identify the reasons why adolescents victimize their peers due to their ethnic background. To address this limitation, we examined: (1) the extent to which prejudiced attitudes within adolescents’ close and larger social networks determine their engagement in ethnic harassment, and (2) the extent to which classroom ethnic diversity plays a role in any such link. Our sample included 902 Swedish adolescents (M age ?=?14.40, SD?=?.95; 50.3% girls). We found that Swedish adolescents who held negative attitudes toward immigrants or who were surrounded by prejudiced peers were more likely to be involved in ethnic harassment, particularly in classrooms with high ethnic diversity. Adolescents in classrooms with a high anti-immigrant climate were more likely to harass their immigrant peers. These findings suggest that prejudiced beliefs in youth social networks put young people at risk of engaging in ethnic harassment, particularly in ethnically diverse classrooms. 相似文献
757.
Naoise Mac Giollabhui Johanna Nielsen Sam Seidman Thomas M. Olino Lyn Y. Abramson Lauren B. Alloy 《Journal of youth and adolescence》2018,47(10):2129-2142
Hopelessness is implicated in multiple psychological disorders. Little is known, however, about the trajectory of hopelessness during adolescence or how emergent future orientation may influence its trajectory. Parallel process latent growth curve modelling tested whether (i) trajectories of future orientation and hopelessness and (ii) within-individual change in future orientation and hopelessness were related. The study was comprised of 472 adolescents [52% female, 47% Caucasian, 47% received free lunch] recruited at ages 12–13 who completed measures of future orientation and hopelessness at five annual assessments. The results indicate that a general decline in hopelessness across adolescence occurs quicker for those experiencing faster development of future orientation, when controlling for age, sex, low socio-economic status in addition to stressful life events in childhood and adolescence. Stressful childhood life events were associated with worse future orientation at baseline and negative life events experienced during adolescence were associated with both an increase in the trajectory of hopelessness as well as a decrease in the trajectory of future orientation. This study provides compelling evidence that the development of future orientation during adolescence is associated with a faster decline in hopelessness. 相似文献
758.
Nicole M. Schmidt Marvin D. Krohn Theresa L. Osypuk 《Journal of youth and adolescence》2018,47(10):2009-2026
Residential mobility is one documented stressor contributing to higher delinquency and worse educational outcomes. Sensitive period life course models suggest that certain developmental stages make individuals more susceptible to the effects of an exposure, like residential mobility, on outcomes. However, most prior research is observational, and has not examined heterogeneity across age or gender that may inform sensitive periods, even though it may have important implications for the etiology of adolescent development. Moreover, there are important translational implications for identifying the groups most vulnerable to residential mobility to inform how to buffer adverse effects of moving. In this study, low-income families were randomized to residential mobility out of public housing into lower poverty neighborhoods using a rental subsidy voucher (“experimental voucher condition”), and were compared to control families remaining in public housing. The sample was comprised of 2829 youth (51% female; 62% Non-Hispanic Black, 31% Hispanic, 7% other race). At baseline, youth ranged from 5 to 16 years old. This study hypothesized that random assignment to the housing voucher condition would generate harmful effects on delinquency and educational problems, compared to the control group, among boys who were older at baseline. The results confirmed this hypothesis: random assignment to the experimental voucher condition generating residential mobility caused higher delinquency among boys who were 13–16 years old at baseline, compared to same-age, in-place public housing controls. However, residential mobility did not affect delinquency among girls regardless of age, or among boys who were 5–12 years old at baseline. The pattern of results for educational problems was similar but weaker. Families with teenage boys are particularly vulnerable to residential transitions. Incorporating additional supports into housing programs may help low-income, urban families to successfully transition to lower poverty neighborhoods. 相似文献
759.
Jasmine Fardouly Natasha R Magson Carly J Johnco Ella L Oar Ronald M Rapee 《Journal of youth and adolescence》2018,47(7):1456-1468
Time spent on social media and making online comparisons with others may influence users’ mental health. This study examined links between parental control over the time their child spends on social media, preadolescents’ time spent browsing social media, preadolescents’ appearance comparisons on social media, and preadolescents’ appearance satisfaction, depressive symptoms, and life satisfaction. Preadolescent social media users (N?=?284, 49.1% female; aged 10–12) and one of their parents completed online surveys. Preadolescents, whose parents reported greater control over their child’s time on social media, reported better mental health. This relationship was mediated by preadolescents spending less time browsing and making fewer appearance comparisons on social media. Parental control over time spent on social media may be associated with benefits for mental health among preadolescents. 相似文献
760.
Laura M. Padilla-Walker Sarah M. Coyne Savannah L. Kroff Madison K. Memmott-Elison 《Journal of youth and adolescence》2018,47(2):445-459
The goal of the current study was to examine the protective role that maternal media monitoring might have for adolescents. This was done by considering whether styles of media monitoring either directly reduced media use, or whether they buffered the associations between aggressive media use and adolescents’ prosocial behavior, aggression, and delinquency. Participants were 681 adolescents from two cities in the United States (51% female; 73% white), and their mothers, who provided data at two different time points, 2 years apart (when adolescents were roughly ages 13 and 15). Mixture modeling results revealed that mothers used four different styles of media monitoring made up of combinations of active and restrictive monitoring as well as forms of co-use. Styles that included active monitoring and connective co-use (i.e., engaging in media with the intent to connect with children) were directly associated with less media use, and moderated links between adolescents’ media use and behavioral outcomes concurrently but not longitudinally. The discussion was focused on the strength of considering multiple strategies of media monitoring together, and how this approach can inform future research in the area of parental media monitoring. 相似文献