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41.
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.  相似文献   
42.
The report presents the case of a 33-year-old man under the primary assumption of homicide in which the court-ordered autopsy revealed death as a result of bleeding due to a spontaneous rupture of the urinary bladder. The article gives a short summary of the pathomorphological findings and their respective causes, for example the typical location of the rupture at the posterior wall and roof of the bladder and the common concomitant drunkenness. Furthermore, obligatory forensic investigations--beside the autopsy--are mentioned and discussed.  相似文献   
43.
Sudden unexpected death in an infant caused by or associated with neoplasm is rare. We describe a case of a sudden death in an apparently healthy 3-month-old female, in which the autopsy revealed a multiple type II infantile hepatic hemangioendothelioma (IHE). This uncommon tumor has, untreated, a relatively high mortality rate, mainly due cardiac failure resulting from massive arteriovenous shunts, but the association with sudden infant death is very rare.  相似文献   
44.
45.
Amniotic fluid embolism (AFE), a relatively rare complication in pregnancy, has a high mortality rate. We describe a case of a 38-week pregnant woman with such an embolism leading to almost immediate death after a blunt abdominal trauma inflicted in a motor vehicle accident and probably associated with improper positioning of a seat belt. It has been assumed that the pathophysiology of amniotic fluid embolism is related to an anaphylactoid reaction and that mast cell degranulation indicates this mechanism. Moreover, immunohistochemical antitryptase staining of pulmonary tissue samples in our case revealed mast cell degranulation.  相似文献   
46.
Fibronectin, MRP8, MRP14 and defensin were detected immunohistochemically in 46 surgically treated, fresh (hours old) human wounds and in wounds of 13 individuals who died immediately from fatal trauma (airplane crashes or train rollovers). In immediate fatal trauma, it was not possible to detect fibronectin outside of bleeding areas nor could inflammatory cells be visualized in the interstitium using MRP8, MRP14, or defensin antibodies. Fibronectin staining could be regularly demonstrated in wounds at least 20 min-old. Granulocytic infiltrates limited to the perivasal space could be detected 20-30 min after infliction of the wound expressing MRP8, MRP14 and defensin. It was also possible to detect fibronectin networks and MRP8-, MRP14-, and defensin-positive granulocytes and macrophages in particular wounds up to 30 days-old. No differences between the expression of MRP8 and MRP14 could be demonstrated in the wounds, the majority of which were only several hours old. As wound age increased, the number of defensin-positive granulocytes detected decreased. The immunohistochemical detection of fibronectin is a useful way to demonstrate vitality in fresh wounds, beginning about 20-30 min post-trauma. However, detection of MRP8, MRP14 and defensin provides no advantage over the routine histological detection of granulocytes and macrophages in wounds under 1-2 days old.  相似文献   
47.
Fatty acid ethyl esters (FAEE) can be used as alcohol markers in hair. It was investigated in this study whether this diagnostic method is disturbed by hair care and hair cosmetics. Traces of ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate were detected in all of 49 frequently applied hair care products by headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). The highest concentration was 0.003% in a hair wax. From experiments with separated hair samples of alcoholics as well as from the evaluation of the FAEE concentrations and the data about hair care of 75 volunteers (alcoholics, social drinkers and teetotalers) follows that usual shampooing, permanent wave, dyeing, bleaching or shading are of minor importance as compared to the drinking amount and other individual features. However, false positive results were found after daily treatment with a hair lotion containing 62.5% ethanol, with a deodorant and with a hair spray. As an explanation, it is assumed that FAEE are formed in the sebum glands also after regular topical application of products with a higher ethanol content.  相似文献   
48.
The article summarises three fatalities after attacks by wild animals. The first case describes a 90-year-old woman who died as a result of pneumonia after a bear fell on her and caused multiple chest fractures. The second case deals with a 76-year-old woman who was hit in the middle face by the hoof of a camel and, thereafter, died of myocardial infarction. The third case describes a 27-year-old biologist who died from severe blunt trauma after an attack of a wild living elephant. The article gives a summary of typical injury patterns of selected wild animals and outlines potential reasons of death as a result of the injuries.  相似文献   
49.
The 4-methylaminorex (4-MAX) is an amphetamine-related psychostimulant drug that has appeared on the clandestine market with a street name of "U4Euh". This compound exists as four stereoisomers, trans-4R,5R, trans-4S,5S, cis-4R,5S and cis-4S,5R, of which the cis forms have been classified as Schedule I substances in the US. The increasing variety of designer drugs has highlighted the importance of detection, identification, and quantitative measurement of these drugs, including 4-MAX, in biological samples. In the present study, the isomers of 4-MAX were detected in urine of rats treated with the drugs by some but not all of the on-site immunoassays tested, mainly as amphetamine or methamphetamine. To facilitate identification of 4-MAX by laboratories specialized in drug analysis, the electron-ionization mass spectrum and TLC data for underivatized 4-MAX using a routine laboratory drug-screening procedure is provided. In addition, a GC/MS method is described for the quantitative determination of cis- and trans-4-MAX as tert-butyldimethylsilyl-derivatives in plasma, urine and tissue.  相似文献   
50.
Development of depressive tendencies was assessed over a 9-year period in a random sample of 389 Finnish children. Predictors of maternal role satisfaction and hostile child-rearing attitudes, assessed when the children were ages 6 and 9 years, respectively, and a temperament predictor of perceived child difficultness, assessed when the children were age 6 years, were measured using questionnaires designed for this study. Depressive tendencies were assessed by a self-report at age 15 (modification of Beck's Depression Inventory). Using structural equation modeling, we tested a hypothesized model comprising direct as well as mediated effects between the childhood predictor variables and adolescent depressive tendencies. The results indicated support for a similar mediational model in girls and boys. Low maternal role satisfaction and maternal perceptions of child difficultness, measured when children were age 6 years, predicted hostile maternal child-rearing attitudes measured when children were age 9 years, which in turn had a significant direct effect on depressive tendencies among these children during adolescence. The only other direct effect was found solely in girls: Low maternal role satisfaction predicted adolescent depressive tendencies. These results underline the close interplay of child temperament and mothering factors in the development of depressive tendencies in girls and boys.  相似文献   
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