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81.
The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy" is a currently used or abused designer drug and fatalities are frequently encountered in forensic practice. However, the question remains open whether an MDMA blood level can be toxic or even potentially lethal. In order to provide insight in the interpretation of a detected MDMA concentration, the distribution of MDMA and its metabolite 3,4-methylenedioxyamphetamine (MDA) in various body fluids and tissues was studied and discussed in two different fatalities. Apart from peripheral blood samples (such as femoral and subclavian blood), various blood samples obtained centrally in the human body and several body fluids (such as vitreous humour) were examined. In addition, various tissues such as cardiac muscle, lungs, liver, kidneys, and brain lobes were analysed. In contrast to the peripheral blood levels, high MDMA and MDA levels were found in cardiac blood and the majority of the organs, except for the abdominal adipose tissue. The high concentrations observed in all lung lobes, the liver and stomach contents indicate that post-mortem redistribution of MDMA and MDA into cardiac blood can occur and, as a result, blood sampled centrally in the body should be avoided. Therefore, our data confirm that peripheral blood sampling remains "the golden standard". In addition, a distinct difference in peripheral blood MDMA concentrations in our two overdose cases was established (namely 0.271 and 13.508 microg/ml, respectively). Furthermore, our results suggest that, if a peripheral blood sample is not available and when putrefaction is not too pronounced, vitreous humour and iliopsoas muscle can be valuable specimens for toxicological analysis. Finally, referring to the various mechanisms of death following amphetamine intake, which can result in different survival times (e.g. cardiopulmonary complications versus hyperthermia), the anatomo-pathological findings and the toxicological results should be considered as a whole in arriving at a conclusion.  相似文献   
82.
In animal experiments and in cell culture, chronic morphine treatment has been followed by "up-regulation" as well as "down-regulation" of the mu-opioid receptor (OR) number. The present postmortem morphometric study of morphine-related fatalities of drug-addicts (n=13, 20-35 years old, with blood unconjugated morphine levels from 27.1 ng/ml to 458 ng/ml, m.v. 198.5 ng/ml) versus a non-addicted control group (n=13, 10-44 years old) was intended to examine, whether chronic opiate exposure affects the numerical density of mu-OR expressing neurons in the human neocortex (areas 11, 24 and 25 according to Brodmann). For the immunohistochemical procedure, vibratome sections (100 microm) were incubated with a monoclonal antibody against the mu-OR, diluted 1:100, and immunolabelled sites were visualized using an immunoperoxidase protocol. The numerical densities of OR immunoreactive neuronal profiles and Nissl-stained central profiles were assessed morphometrically (camera lucida-drawings). In both groups, the anti-mu-OR-immunoreactivity was mainly localized in pyramidal neurons of layers (L) II/III and V and in multiform neurons of L VI. In the areas 24 and 25, the density of the immunoreactive neuronal profiles did not display a significant difference between the two examined groups. In the area 11, however, the number of immunolabelled neuronal profiles amounted to 2777+/-206 mm(3) in the drug-related fatalities and to 2320+/-124 mm(3) in the control group and thus was significantly increased.  相似文献   
83.
This article describes a fully automated procedure for detecting cannabinoids in human hair samples. The procedure uses alkaline hydrolysis and headspace solid-phase dynamic extraction (HS-SPDE), followed by on-coating derivatization and gas chromatography-mass spectrometry (GC-MS). SPDE is a further development of solid-phase microextraction (SPME), based on an inside needle capillary absorption trap. It uses a hollow needle with an internal coating of polydimethylsiloxane as extraction and pre-concentration medium.Ten mg of hair were washed with deionised water, petroleum ether and dichloromethane. After adding deuterated internal standards, the sample was hydrolyzed with sodium hydroxide and directly submitted to HS-SPDE. After absorption of analytes for an on-coating derivatization procedure, the SPDE-needle was directly placed into the headspace of a second vial containing N-methyl-N-trimethylsilyl-trifluoroacetamide before GC-MS analysis. The limit of detection was 0.14 ng/mg for Delta(9)-tetrahydrocannabinol, 0.09 ng/mg for cannabidiol, and 0.12ng/mg for cannabinol. Absolute recoveries were in the range of 0.6 to 8.4%. Linearity was verified over a range from 0.2 to 20 ng/mg, with coefficients of correlation between 0.998 and 0.999. Intra- and inter-day precision were determined at two different concentrations and resulted in ranges between 2.3 and 6.0% (intra-day) and 3.3 and 7.6% (inter-day). Compared with conventional methods of hair analysis, this automated HS-SPDE-GC-MS procedure is substantially faster. It is easy to perform without using solvents and with minimal sample quantities, and it yields the same sensitivity and reproducibility. Compared to SPME, we found a higher extraction rate, coupled with a faster automated operation and greater stability of the device.  相似文献   
84.
This contribution aims at examining the extent to which patent related indicators are relevant for shedding light on the notion of excellence within knowledge-generating institutions. Traditionally, excellence has been looked upon as the ability to create interesting and valuable new scientific concepts, theories and data. From such a perspective, scientific excellence can be assessed through scientometric measures of publication output and impact. The recent interest in the entrepreneurial phenomenon within knowledge-generating institutes justifies efforts to examine the relevancy of broadening the set of indicators used to assess such institutions into the direction of entrepreneurial excellence. In this paper we will examine the relevancy of using patent data in order to delineate such additional, more entrepreneurial oriented, indicators. The arguments and findings presented in this respect will lead us to a plea for the use of these indicators in a contextualized manner.  相似文献   
85.
86.
The Illusion of Transparency in Negotiations   总被引:1,自引:0,他引:1  
The authors examined whether negotiators are prone to an illusion of transparency, or the belief that their private thoughts and feelings are more discernible to their negotiation partners than they actually are. In Study One, negotiators who were trying to conceal their preferences thought that their preferences had leaked out more than they actually did. In Study Two, experienced negotiators who were trying to convey information about some of their preferences overestimated their partners' ability to discern them. The results of Study Three rule out the possibility that the findings are simply the result of the curse of knowledge, or the projection of one's own knowledge onto others. Discussion explores how the illusion of transparency might impede negotiators' success.  相似文献   
87.
Already the Celts and ancient Germanic peoples knew about the poisonousness of the yew, which played an important part in the mythology of these civilizations. For hunting, the arrows were made poisonous with yew juice, and yew leaves were used for homicide and suicide. In modern times taxine is rarely used with suicidal intent, although this method is actually recommended on the respective Websites. After a 14-year-old boy had intensively studied poisonous plants and methods of suicide on various Websites, he cut leaves from a yew tree (taxus baccata) in his parents' garden, crushed and ingested them and died soon afterwards. At the forensic autopsy pieces of the partially crushed, partially completely preserved yew leaves were found in the stomach. The histological findings were unspecific, e.g. marked general blood congestion of the internal organs and pronounced cerebral and pulmonary edema. When the tree leaves found in the stomach were viewed under the light microscope, a stoma typical of taxus was observed; chemical-toxicological investigations revealed 3,5-dimethoxyphenol in the gastric content, which is considered a marker for the ingestion of taxus.  相似文献   
88.
The authors report on a woman who died on the age of 75 years and who was found dead in her dwelling with an extensive injury of the left thigh two days after the last sign of life. Together with the corpse a poodle was present in the dwelling. Due to the unusual localization totally beneath the clothes (trousers) and the morphology of the injury an unnatural cause of death was suspected. According to the autopsy findings and the histological results, postmortal animal scavenging caused by the poodle remained the only explanation for the injury. Supplementary DNA testing yielded final certainty.  相似文献   
89.
This study was conducted in an attempt to develop a metallographic method for the investigation of pipe bombings. Three common pipe materials, ASTM A53 steel, AISI 304L stainless steel, and 6061-T6 aluminum, were shock-loaded using five high explosives and three propellants. The explosives used were ANFO, Composition C4, C6 detasheet, nitroglycerine-based dynamite, and flake TNT. The propellants used were FFFFg black powder. Red Dot smokeless powder, and Turbo Fuel A. The post-blast microstructure, hardness, and, in the case of 304L, transformed martensite content were examined for each test. The damage done to the microstructure was found to increase with increasing detonation velocity of the explosives and increase in pressure generated by the shock-metal interaction. Material hardness and, in the case of 304L, martensite content showed a sharp increase followed by a plateau as the shock pressure and detonation velocity increased.  相似文献   
90.
Recently, several new pieces of water legislation have been promulgated in both Zimbabwe and the Republic of South Africa. The new acts are an attempt to correct injustices of a colonial past and to trigger development towards effective, equitable and efficient integrated water resources management influenced by the policy decisions in Agenda 21 and the need to respect economic and social human rights. This article aims at identifying and describing factors of prime importance in the process of legal and institutional reform. Major factors are earmarked and derived from the proceedings in Zimbabwe and are compared with the situation in South Africa. Thorough analysis by the author of proceedings, preambles, memoranda, legislation and addenda has induced roughly 5 major reform issues: The call for equitable water distribution based on a widely consented water resources management strategy; The need for effective and efficient integrated water resources management conducive to stakeholder participation through decentralisation processes; The redressing of legal shortcomings in former water legislation with the emphasis on the introduction of integrated approaches; The introduction of instruments of cost recovery for water resources management; The need to develop human resources capacity and institutional strength within the implementing agencies.For both Southern African states, these issues appear to be of comparable importance as major triggers for legal and institutional reform, although not always in the same sense.The resulting most important legal and institutional changes are presented, discussed and compared. Finally, prospects for and constraints on implementation of the new water legislation in these countries are compared.  相似文献   
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