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951.
952.
The reconstruction of killing offences often requires the differentiation between vital and postmortal blood traces at the sites of action and finding. Earlier investigations seemed to imply the possibility of such a differentiation depending on the different clot structure. We therefore examined clots prior and after 10 minutes of complete occlusion of the upper extremity morphologically and morphometrically with the REM. The morphologic comparison of these clots revealed narrow, round shaped fibrin fiber networks for clots of native blood, whereas clots after occlusion showed linear, rarely connected long fibrin fibers. The morphometry of the fibrin free spaces revealed a significant enlargement of the single fibrin free spaces as well as of the total fibrin free space after occlusion. For capillary blood a significant decrease in fiber diameter was observed after occlusion. The examination of clinical clotting parameters revealed alterations of thrombocyte aggregation for the collagen induction, a slightly reduced thrombocyte retention and slightly steeper flanks in the thromboelastogram after occlusion. The reason for these changes was interpreted as lack of high energetic phosphates in the retraction process as the clotting cascade itself requires a very high amount of these phosphates. Use of these results in the forensic practice will have to take factors as temperature, drying out, surface-structure and many others into account. 相似文献
953.
Prostaglandins (PGs) are essential for many physiological and pathological processes. As they are not stored in tissue, their presence and actions therefore result from de novo synthesis and release. Although platelets themselves appear to have the ability to synthesize TxA2, PGD2, arachidonic acid may also be metabolized in the lipoxygenase pathway in platelets, producing 12-hydroperoxy/12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HPETE/12-HETE). CFLP mice were infected intranasally with A/H3N2/Hong Kong (1/68) influenza virus. Platelets were isolated from the control (saline treated) and infected mice 3-13 days after virus application. Platelets were isolated from the diluted arterial blood of the mice. Metabolites of arachidonate cascade were determined using 1-14C-arachidonic acid (2035 MBq/mM spec. act.) as substrate. All incubations were carried out in TC Medium 199 (pH 7.4) at 37 degrees C for 10 min. Radiolabelled products were separated and quantitatively determined. The synthesis of TxA2 in the platelets of animals was found to be significantly increased 7 days after the virus infection. The 12-hydroxy-heptadecatrienoic acid level was higher on the 10th and 13th days of infection, as were the products of the lipoxygenase pathway. 相似文献
954.
Investigation of 14 roentgenograms of skin preparations with cut-stab wounds, treated by spatial filtration method in medium and high spatial frequency modes was performed using material of 13 specific cases. This resulted in detection of disturbances of skin pattern left at the area of former skin cone in 7 cases while in 2 cases indistinct heel traces were seen. Changes in skin pattern were not recorded on roentgenograms of skin preparation of 12 experimental cut-stab wounds obtained on cadaveric skin. 相似文献
955.
956.
Histo- and ultrastructure of bone tissue in 28 persons (2 section observations and 26 cases of bone biopsy analysis) with congenital fragility of the bones and dysosteogenesis were studied. Age of the victims ranged from 6 months to 38 years (20 men and 8 women). Against the background of bone rarefaction and decrease in quality of basic bone substance the quantity of osteocytes for a unit of osseous beam area increases. Electron-microscopic investigation revealed changes in osteoblast structure (3 types detected) by the degree of development of granular endoplasmic reticulum. In the 2nd and 3d type of osteoblasts the decrease in the quantity of elements of granular endoplasmic reticulum was noted which may be connected with disturbance of biosynthetic processes in cell and fibrillogenesis with maturation of collagenous fibrils and their mineralization. Histo- and ultrastructure of the bone in dysosteogenesis are rather typical and in total with clinico-roentgenological data are informative enough for making diagnosis. 相似文献
957.
This study investigated the transfer of cocaine and its metabolites from plasma into the cerebrospinal fluid. The concentration of cocaine and its metabolites in plasma and cerebrospinal fluid was determined by radioimmunoassay because this method only, the sum of the drug and metabolites restored. In sheeps a sublethal cocaine hydrochloride dose (2,4 mg/kg b. wt.) was administered intraarterial daily for up to 8 days. In the first hours after administration the concentration of cocaine in cerebrospinal fluid was low. It is supposed that a barrier against the transport of cocaine from blood into cerebrospinal fluid exists. After intrathecal administration a delay of transport could from CSF to blood not be seen. 相似文献
958.
959.
960.