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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.
Research has shown that the prevalence of deliberate self-harm (DSH) is higher in adolescents than in adults, but little is known about other differences. In this study we compare adolescent and adult DSH-patients regarding factors contributing to the suicidal act. In two regions in Norway, 98 persons under 20 years of age and 83 older persons were interviewed following an act of DSH. They were compared regarding intentions involved in the DSH, precipitating circumstances, level of suicidal intent, medical seriousness of the act, depression, hopelessness, and self-esteem. Few differences were found. The adults more often wanted to escape from unbearable thoughts or situations, or to receive care and attention. Adults also reported a slightly higher level of medical seriousness of the DSH act, more psychiatric problems, and substance abuse. The similarities between young and adult DSH-patients are striking. The differences found are most likely related to factors of age itself, such as cognitive immaturity, impulsivity, and lack of experience in enduring problems. 相似文献
924.
A 1H nuclear magnetic resonance (1H NMR) method for the determination of gamma-hydroxybutyric acid (GHB) and gamma-hydroxybutyrolactone (GBL) in human serum and urine using spiked samples has been developed. The method gives linear responses (correlation coefficients of 0.99 or greater) over the concentration range 0.01 mg/mL to 4.0 mg/mL in urine and 0.3 mg/mL to 2.0 mg/mL in serum. No sample pretreatment is required. Studies of the chemical interconversion of GBL and GHB showed hydrolysis of GBL to be rapid at pH 11.54, slower and less complete (30% hydrolysis) at pH 2.54 and slowest at pH 7.0, reaching 30% hydrolysis in about 40 days. No esterification of GHB was observed at any pH. 相似文献
925.
In a second test of an arthropod saturation hypothesis, we analyzed if the on-campus Anthropology Research Facility (ARF) at the University of Tennessee, Knoxville, with its 20+ yr history of carcass enrichment, is comparable to non-enriched sites in community structure of predatory and parasitic arthropods that prey upon the sarcosaprophagous fauna. Over a 12-day period in June 1998, using pitfall traps and sweep nets, 10,065 predaceous, parasitic, and hematophagous (blood-feeding) arthropods were collected from freshly euthanized pigs (Sus scrofa L.) placed at ARF and at three surrounding sites various distances away (S2-S4). The community structure of these organisms was comparable in most paired-site tests with respect to species composition, colonization rates, and evenness of pitfall-trap abundances on a per carcass basis. Site differences were found in rarefaction tests of both sweep-net and pitfall-trap taxa and in tests of taxonomic evenness and ranked abundances of sweep-net samples. Despite these differences, no evidence was found that the predatory/parasitic fauna at ARF was impoverished with fewer but larger populations as a result of carcass enrichment. Comparison of the sarcosaprophagous and predatory/parasitic faunas revealed a tighter (and more predictable) linkage between carrion feeders (sarcosaprovores) and their carrion than between carrion feeders and their natural enemies (predators and parasitoids), leading us to conclude that ARF is more representative of surrounding sites with respect to the sarcosaprovore component than to the predatory/parasitic component within the larger carrion-arthropod community. 相似文献
926.
A few papers in the literature reported incident deaths by acute ketamine poisoning. In this paper, we report an unusual homicide caused by chronic ketamine poisoning. The victim was a 34-year old married woman with no previous medical history (except as reported herein) who died in her own home. The court investigation revealed that she was chronically poisoned by her husband over a period of about one year in an act of homicide. Determination of ketamine concentrations in autopsy specimens was carried out with gas-chromatography/mass spectrometry (GC-MS). The results showed that ketamine concentration was 21 microg/mL in gastric contents, 3.8 microg/mL in blood and 1.2 microg/mL in urine. The most striking forensic findings were cardiac muscle fibrosis and hyaline degeneration of small arteries in victim's heart, the pathological features of ketamine poisoning previous reported only in animal studies. 相似文献
927.
928.
Efficient capillary electrophoretic STR analysis requires rapid, reproducible and robust separation of DNA fragments with reasonable capillary longevity--this is currently accomplished using proprietary commercial polymeric sieving matrices specifically developed for this separation. These matrices, while effective, are costly and do not provide adequate resolution of STR DNA fragments in capillaries with shorter effective separation lengths, increasing the time required to accomplish the separation and minimizing the potential extrapolation to other miniaturized platforms. As the forensic community looks toward next generation microchip technology as a means of processing casework more rapidly, new sieving polymers need to be evaluated for utilization in this platform. The research presented here describes the assessment of commercially-available polymeric sieving matrices for STR analysis, with consideration given to feasibility of incorporation into a microdevice. Polymer composition, molecular weight, and concentration were evaluated, along with an assessment of the effects of buffer composition, separation temperature, and capillary length. These variables were evaluated individually or collectively on the ability to resolve STR DNA fragments and the reproducibility of the separations and the results compared to a proprietary commercial product. A 600,000 Da MW poly(ethylene oxide) (PEO) solution at a 3% (w/v) concentration was determined to be the most suitable matrix for these separations. This polymer, in coated capillaries, provided highly robust and reproducible separations, with near baseline resolution of fragments having single base differences. Reductions in the temperature of the separation, from 60 degrees C to 40 degrees C, and the urea concentration of the buffer, from 7 M to 3.5 M, provided increased longevity of the PEO polymer for repeated separations. Comparison of this polymer with currently specified commercial products used for STR analysis showed that the optimized PEO matrix provided superior separations under all conditions tested. In addition, PEO could be utilized in shorter capillary systems, with a concurrent decrease in analysis time, highlighting its potential for use in shortened capillary or microdevice systems. 相似文献
929.
Fartushnyĭ AF Sukhin AP Gerasimenko AI Shevchenko VV Sborshchik EA 《Sudebno-meditsinskaia ekspertiza》2005,48(2):38-41
A method was suggested for identifying reladorm and donormil in pharmaceutical drugs and biological objects. The above substances are isolated by 96% ethanol or by mixture of chloroform and isopropanol. 7 color reactions, 3 microcrystalloscopic reactions and chromatography in thin sorbent layer are suggested for identification. 相似文献
930.
The technique is proposed allowing quantitation of brain edema and typing of liquor distribution in different parts of brain tissue. In combination with other assays this test can determine a variant of tanatogenesis, detect cause of death and duration of the terminal period. The method application is illustrated by the study of brain hydration in mechanical strangulation asphyxia. It is shown that this death is associated with hypohydration of cerebral structures, especially pronounced in the cortical compartments. 相似文献