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The relationships between the inert tension of the head and the morphologic substrates of brain injuries were under study. A comparative clinical and morphologic analysis of lethal contusion and axonal injuries underlie this investigation. Differences in the neurologic semeiotics and CT data in such injuries are presented. The authors discuss the mechanisms of the physical processes in the skull, resulting in focal and diffuse injuries of the brain. Quantitative assessment of the traumatic cerebral substrates is given and relations of these parameters to the conditions of the head trauma (the direction of the external injurious factor action) and the clinical picture are shown. The results of this study may be useful in establishing some circumstances of craniocerebral injuries. 相似文献
918.
A large number of passerine birds, mainly greenfinches, were found dead or dying in a hedgerow close to a field of onions recently sprayed with sodium monochloroacetate (SMCA). An analytical method is described for isolating monochloroacetic acid from bird tissues, as its potassium salt, by ion exchange chromatography. The ion exchange eluate is evaporated to dryness, acidified, extracted with ether and the ethereal extract methylated with diazomethane. The concentration of the methyl ester of monochloroacetic acid is determined using the Mass Selective Detector in the selected ion mode. Chemical analysis confirmed the exposure of the birds to SMCA. It is calculated that 50 microliter of spray contained the lethal dose of SMCA for a greenfinch. 相似文献
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P Betz A Nerlich J Wilske I Wiest C Kunze O Peschel R Penning 《Forensic science international》1992,53(2):193-202
We monitored the immunohistochemically determined amount of surfactant-producing alveolar type II cells in human fetal lung using polyclonal antibodies against apoprotein B and C of human pulmonary surfactant. Lungs of 30 dead-born fetuses without lung affection aged between 15 and 38 weeks of gestation were evaluated and the surface density of surfactant-producing alveolar type II cells was determined by morphometry. In lungs of fetuses with a gestational age less than 22 weeks no relevant number of positively reacting cells could be found. Between the 22nd and 29th week a progressive increase with considerable inter-individual variability was observed. From the 30th week on the number of the type II pneumocytes appeared rather constant without further significant increase. We provide evidence that the immunohistochemical detection of surfactant-producing alveolar type II cells is useful for the determination of the age of unknown and especially fragmented fetuses: The lack of surfactant-producing alveolar type II cells in fetal lungs before the 22nd week allows a rather safe distinction between fetal lungs of higher age from those of lesser age. Between the 22nd and 29th week an age-dependent increase in the number of these cells occurs with wide inter-individual variability allowing only an approximate age determination. In particular, this may be an important piece of information in fragmented fetal corpses. Furthermore, the number of surfactant-producing alveolar type II cells provides additional information on pulmonary maturation and may thus be helpful in the estimation of a theoretical survival chance. 相似文献