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A 6-month-old girl died suddenly without any previous symptoms of heart failure. Autopsy examination showed cardiomegaly (97 g) with a severely fibrotized myocardium. The left coronary artery was originating from the pulmonary artery. Histologically, the myocardium showed myocardial infarcts of different ages, as well as grossly thickened arterial branches due to increased flow in left-right shunt. We suggest that rare anomalies of the coronary arteries should be considered in the autopsies of suspected sudden infant death syndrome cases.  相似文献   
154.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
155.
Veto Players and Civil War Duration   总被引:1,自引:0,他引:1  
Civil wars show a remarkable variation in how long they last. Some end within days; others continue for decades. What explains the extreme intractability of some wars while others are resolved quickly? This article argues that conflicts with multiple actors who must approve a settlement (veto players) are longer because there are fewer acceptable agreements, information asymmetries are more acute, and shifting alliances and incentives to hold out make negotiation more difficult. This veto player approach to explaining variation in civil war duration is tested using a new dataset containing monthly data on all parties to each civil war begun since World War II. The statistical analysis shows a strong correlation between the number of veto players and the duration of civil war.  相似文献   
156.
Washington University v. Catalona revolves around ownership of tissue samples provided by patients for research purposes, raising significant ethical and legal questions concerning patient rights, current human research practices, and the treatment of samples as capital resources by the research institution.  相似文献   
157.
In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported.  相似文献   
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In a case of suicidal application of electricity differences between the rectal temperature of the body and the suspected time of death were observed.In order to answer the question whether an electric current from hand to hand over >30 min led to a rise in body temperature FEM-based computer simulations and animal experiments were carried out. Both resulted in a warming of the soft parts in the arm without warming the body core. Thus a temperature-based estimation of the time since death can also be used in cases with electricity as the cause of death. Besides, in the animal experiment we found a spontaneous rise in the body core temperature even without application of electricity which may be a reason for the typical temperature plateau after death.  相似文献   
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