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961.
A method has been developed for the rapid extraction of cocaine and benzoylecgonine from post-mortem blood and urine samples. Solid phase columns containing C8 packing material gave clean, emulsion free extracts from body fluids. The total time for each extraction was approx. 10 min and the system has the capacity for the simultaneous extraction of up to 10 samples. Urine can be extracted directly, blood samples were sonicated before extraction to allow for their easy passage through the columns. The method gave excellent recoveries of cocaine (98-100%) from spiked samples at concentrations of between 50 ng/ml and 10 micrograms/ml. Analysis of the extracts was by high performance liquid chromatography (HPLC). 相似文献
962.
Signs of hypothermia injury were studied in rabbits cooled to a core temperature of 30 degrees C by immersion in ice water and thereafter rewarmed to 35 degrees C. Anaesthetized control rabbits were kept normothermic (37 degrees C) for a corresponding time (4 h). Creatine phosphokinase (CPK) activity increased 24 h after hypothermia to 20-fold in serum. In cerebrospinal fluid the activity was already significantly (5-fold) increased after hypothermia and was still as high at 24 h. Smaller increase was also found in the control normothermic rabbits both in serum (10-fold) and cerebrospinal fluid (2-fold). The values had returned to the initial level after 1 week. Small haemorrhages were observed in the brain at 24 h and slight scarring was seen in the myocardium of some rabbits which had lived 4 weeks following hypothermia. The results indicate that CPK can be a useful marker in the diagnostics of hypothermia death, especially in cerebrospinal fluid, which is less affected than blood by autolysis. 相似文献
963.
J Schlumbohm 《The History of the Family》1996,1(1):81-95
"Current models of the European demo-economic system in pre-industrial times are based on strong assumptions about the predominant patterns of individual life courses. Now recent micro-studies of individual communities make it possible to check whether the actual patterns of life fit these assumptions. The findings for Belm present an amazing blend of confirmations and contradictions. In particular, the connection between marriage and the formation of a new self-supporting household is subject to doubt. Together with the findings of other micro-studies, the evidence for Belm suggests that the assumptions about mechanisms linking marriage to economic resources should be reconsidered, and that there is need for a dialogue between macro-theories and micro-history." 相似文献
964.
This paper describes a simplified approach to calculating the Bayesian likelihood ratio for the case where two DNA single locus profiles are to be compared. It explains how the calculation allows for band shift and also for the variation in precision with molecular weight. A simple basic theory section explains the principles of the analysis but more detailed explanations are given in an advanced theory section. Experiments on substantial data collections are described which demonstrate the robustness of the method. 相似文献
965.
R S Shiels 《Journal - Forensic Science Society》1992,32(3):245-248
A woman pleaded guilty to road traffic offences and was sentenced to be disqualified for holding or obtaining a driving licence for six months. Her appeal against that sentence was allowed on the basis that she was suffering from premenstrual tension at the time of the offences, and that the disqualification imposed was neither necessary nor appropriate. 相似文献
966.
J Potter 《Journal - Forensic Science Society》1992,32(3):249-255
967.
A small experiment is described which uses databases of Afro-Caribbeans and Caucasians to establish the quality of information that might be given to an investigator about the ethnic group of the donor of an unknown crime stain. The results show that the technique can provide qualified indications, but categoric conclusions are not, in general, feasible. An appraisal is given of the technique within the operational context. 相似文献
968.
J E Allard 《Journal - Forensic Science Society》1992,32(1):49-58
Lorraine Benson's body was found beaten and strangled at Raynes Park, Surrey, in December 1988. Considering the possibility of linked offences, a murder squad was set up to work alongside a team already investigating a rape series in the Kingston area. A man's handkerchief left at a site a quarter of a mile from the murder scene was found to be stained with blood and saliva matching that of the victim. A DNA profile was obtained from a stain of nasal mucus on this handkerchief and found to match a suspect later arrested for an attempted rape in the same locality. Also of forensic interest were dust marks made by the zips of the victim's and defendant's coats and identification of the rope used for strangulation. 相似文献
969.
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
970.
Christopher Cambron Rick Kosterman Richard F. Catalano Katarina Guttmannova J. David Hawkins 《Journal of youth and adolescence》2018,47(2):369-382
There is broad agreement that neighborhood contexts are important for adolescent development, but there is less consensus about their association with adolescent smoking and alcohol use. Few studies have examined associations between neighborhood socioeconomic contexts and smoking and alcohol use while also accounting for differences in family and peer risk factors for substance use. Data drawn from the Seattle Social Development Project (N?=?808), a gender-balanced (female?=?49%), multiethnic, theory-driven longitudinal study originating in Seattle, WA, were used to estimate trajectories of smoking and alcohol use from 5th to 9th grade. Time-varying measures of neighborhood socioeconomic, family, and peer factors were associated with smoking and alcohol use at each wave after accounting for average growth in smoking and alcohol use over time and demographic differences. Results indicated that living in more socioeconomically disadvantaged neighborhoods, lower family income, lower family general functioning, more permissive family smoking environments, and affiliation with deviant peers were independently associated with increased smoking. Lower family functioning, more permissive family alcohol use environments, and deviant peers were independently associated with increased alcohol use. The effect of neighborhood disadvantage on smoking was mediated by family income and deviant peers while the effect of neighborhood disadvantage on alcohol use was mediated by deviant peers alone. Family functioning and family substance use did not mediate associations between neighborhood disadvantage and smoking or alcohol use. The results highlight the importance of neighborhood, family, and peer factors in early adolescent smoking and alcohol use. Future studies should examine the unique association of neighborhood disadvantage with adolescent smoking net of family socioeconomics, functioning, and substance use, as well as peer affiliations. Better understanding of the role of contextual factors in early adolescent smoking and alcohol use can help bolster efforts to prevent both short and long harms from substance use. 相似文献