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Studies have shown that pathological involvement with computer or video games is related to excessive gaming binges and aggressive behavior. Our aims for this study were to longitudinally examine if pathological gaming leads to increasingly excessive gaming habits, and how pathological gaming may cause an increase in physical aggression. For this purpose, we conducted a two-wave panel study among 851 Dutch adolescents (49% female) of which 540 played games (30% female). Our analyses indicated that higher levels of pathological gaming predicted an increase in time spent playing games 6 months later. Time spent playing violent games specifically, and not just games per se, increased physical aggression. Furthermore, higher levels of pathological gaming, regardless of violent content, predicted an increase in physical aggression among boys. That this effect only applies to boys does not diminish its importance, because adolescent boys are generally the heaviest players of violent games and most susceptible to pathological involvement.  相似文献   
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The accuracy of antemortem diagnosis of pulmonary embolism is within the range of just 10-30%, so representing one of the most frequent missed diagnosis in sudden, unexpected death. We describe 43 fatal cases of pulmonary embolism as confirmed by post-mortem examination. The aim of our study was to verify the systematic search for the most common genetic thrombophilias (Factor V Leiden (G1691A) and FII (G20210A) gene variants) and dating the thrombus. As a whole, 41 patients (95.3%) had at least one risk factor. Pre-existing symptoms are described just before fatal embolism in 18 (41.9%) out 43 patients. In 18 out of 43 (41.9%) it was not possible to find the thrombotic site. In 24 out of the remaining 25 cases the involvement of the deep veins of one leg was shown; in 1 case the thrombus was localised in the inferior caval vein. 10 (41.7%) were iliac vein thromboses, 7 (29.1%) femoral, 2 (8.3%) popliteal, 3 (12.6%) posterior-tibial, 1 (4.1%) anterior-tibial and 1 (4.1%) peroneal vein thromboses. In our cohort of patients, 4 (10%) out of 40 cases carried the 20210A prothrombin gene variant in heterozygosis. One (2.5%) out of 40 carried the Factor V Leiden (G1691A) gene variant in heterozygosis. Patients carrying these gene variants in homozygosis or carrying both were not present in our case-series. We strongly underline the relevance of a complete methodological approach, integrating clinical data by means of autopsy findings and histological study. On the contrary, investigating common inherited thrombophilia is not warranted.  相似文献   
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DNA evidence frequently plays an important role in criminal investigations and in some cases may be the only means of convicting a suspect. The constant improvement of DNA analysis techniques affords the individualization of minute amounts of DNA, aggravating the risk of contamination artifacts. In our study, we investigated the prevalence of DNA contamination in the autopsy facilities of the Institutes of Legal Medicine in Essen and Kiel (Germany). Using DNA-free swabs, we took samples from instruments used during autopsy and autopsy tables. Surfaces and instruments were routinely cleaned before sampling. Swabs were subjected to different PCRs to quantify the total amount of DNA and to amplify individual specific STR-markers. In most samples, alleles that could be linked to bodies that had been autopsied before were found. Furthermore, we could show that a DNA transfer from the autopsy table to a body was detectable in four out of six cases investigated. The interpretation of DNA typing results may thus be severely complicated. To avoid DNA contamination, we tried out different cleaning methods, of which only a bleach containing cleaner showed sufficient results.  相似文献   
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Cyanide concentrations of blood samples from fire victims autopsied in the Institute of Legal Medicine, Munich, have been determined. In 25% of 48 analyzed cases cyanide concentrations from 0.52 microgram to 6.24 microgram Cyanide/ml blood have been detected. These results are compared to former studies and the higher mean level in our collective is emphasized. The importance of hydrocyanid acid in the toxicity of fire gases is evidently greater, than assumed. Hydrocyanic acid may be produced from nitrogen continaing polymers during combustion. The quote of these polymers in clothing, furniture, and also in equipment of cars is increasing. Therefore, it is necessary to take more notice of the formation of hydrocyanic acid during combustion, even though carbon monoxide is in general the main toxic agent in fire gases.  相似文献   
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This paper is concerned with the impact of the Medical Device Amendments of 1976 and its implications in terms of innovation. With this objective the paper first describes the Medical Device Amendments of 1976. The paper then reports empirical evidence on the sources of a subset of innovations regulated by the Amendment's clinical chemistry diagnostic products. Finally, based on the pattern of innovations found, some thoughts are expressed about the likely effects of the Amendments.  相似文献   
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We study the rationale for the use of exclusivity to protect transfer of technology in subcontracting agreements. The legal possibility arises through the EU Notice on Subcontracting. Empirically, the link between exclusive agreements and technology transfer among firms in the automotive supply industry in EU candidate countries is surprisingly weak, although with exclusive-supply or exclusive-buying clauses in subcontracting agreements upstream transfer of technology is more likely. Exclusive agreements are often reciprocal, and are typically passed on. Downstream firms are more likely to face and use vertical restraints. Technology trickles upstream: Multinational final assemblers transfer more technology than lower-tier suppliers.  相似文献   
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