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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   
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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   
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A simple and rapid method, for the isolation of eight triazine herbicides from human serum and urine, using Sep-Pak C18 cartridges is presented. After mixing with distilled water, serum and urine samples containing the herbicides, were loaded on Sep-Pak C18 cartridges and eluted with either chloroform only or chloroform/methanol (9:1). The herbicides were detected by capillary gas chromatography with both flame ionization detection (FID) and nitrogen-phosphorus detection (NPD). Separation of eight triazine herbicides from each other and from impurities was generally satisfactory with the use of a non-polar DB-1 capillary column. Recovery of most compounds was excellent for both chloroform and chloroform/methanol (9:1) as elution solvents. Backgrounds were cleaner and evaporation time was shorter for the chloroform only than for the chloroform/methanol (9:1). The NPD gave sensitivity more than 10-20 times higher than that of FID.  相似文献   
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Comparative analysis of ephedrine derivative content in 96 urine specimen obtained from people suspected in abuse with these drugs. Physical and chemical methods of the analysis (gas and thin-layer chromatography) as well as ELISA were used. It was stated that the latter is specific for determination of compounds related to ephedrine by structure and it allows one to detect its analogues in 87 cases. Gas chromatography made it possible to detect ephedrine derivatives in 94 specimen tested and thin-layer chromatography--in 64 specimen tested. The given ELISA may be recommended for medicolegal expert purposes and narcology practice.  相似文献   
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