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921.
922.
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Arrow wounds represent an unusual class of wounds rarely seen by most death investigators. Although the edged, broadhead-tipped arrow produces a wound usually characteristic of archery/crossbow weapons, the plain, field-tipped arrow wound can be confused with gunshot injuries in those cases in which powder residue or firearm projectiles or fragments or both are not recovered. We present a case of a deer carcass with a wound of uncertain firearm or archery origin which initiated a comparison of firearm wounds and archery wounds on fresh road-killed deer. We found the following features to be valuable in the differentiation of gunshot wounds and field-tipped archery wounds: First, the majority of the gunshot wounds (but none of the arrow wounds) had identifiable, macroscopic, wipe-off material and chemically identifiable wipe-off residue by spot test. Second, the archery wound defects had very inconspicuous abrasion rings as compared to the often prominent abrasion rings of gunshot wounds. Third, the actual central defect in the archery wounds was more likely to be oblong or slit-like compared to the gunshot wound defects, which were more likely to be round. 相似文献
924.
925.
Seminal fluid was studied biochemically for sperm identification in stains. The qualitative and quantitative distribution of amino acids in samples of fresh sperm has been alayzed. These findings were compared to the results of a similar study of fresh samples and stains of urine, saliva, vaginal fluor, and sweat. The results obtained show a specific and relatively constant level of amino acids in each of five biological liquids. There was no significant variation in results between fresh samples and stains. 相似文献
926.
Frozen tissues were studied histologically to determine what changes were produced by freezing. Samples of brain, lung, liver, small intestine, and kidney from 20 stray dogs were treated in 3 ways: formalin fixation (control), frozen for 2 days plus formalin fixation, or frozen for 7 days plus formalin fixation. Major histological changes caused by freezing were loss of staining, extracellular fluid accumulation, cell shrinkage, fractures, hemolysis, and hematin formation. Lesser changes included loss of bronchial cilia, prominence of collagen in alveolar septa and meninges, and intracellular vacuolization of epithelial cells. Although these changes were annoying, adequate visualization of the tissues was usually possible. 相似文献
927.
928.
929.
Ultrasonic determinations were made of facial tissue thicknesses in 50 healthy American caucasoid children, ranging in age from 4 to 15. Twenty measurements were taken at sites along the median, right sagittal, and right lateral planes. A static scanner was used in the B-mode. Three measurements significantly increased with age, the mid-philtrum (rs = 0.43, p less than 0.01) in females, the mental sulcus (rs = 0.30, p less than 0.05) in males, and the frontal eminence (rs = 0.32, p less than 0.05) in both sexes. Moreover, 25% of the measurements, while not statistically significant, decreased with increasing age. These data provide a basis for facial reproductions in caucasoid children. 相似文献
930.
P J Knudsen 《Zeitschrift für Rechtsmedizin》1988,101(4):219-227
The Très Haute Vitesse (THV) bullet was introduced to meet the requirements of law enforcement officers, as an alternative to larger calibre fully jacketed bullets, since expanding or exploding bullets are not relevant in Europe. To examine the effect of the THV bullet in tissue, especially the size of the lesion and the degree of overpenetration, 11 recently killed pigs were shot with the weapons used by the Danish Police Force and a 9-mm pistol for reference. The ammunition was THV in the calibres 7.65 mm, 0.38, and 9 mm, using conventional fully jacketed bullets for comparison. The lesions were considerably larger when the THV bullet was used, the entry wound in particular, being roughly twice the diameter in the case of the THV bullet as compared to the fully jacketed bullet of similar calibre. Only one 7.65-mm THV bullet overpenetrated the target when fired against the thorax or abdomen of the pigs and then with only minimal residual energy. All fully jacketed 7.65-mm bullets, all 0.38 bullets, with the exception of one THV bullet, and all 9-mm bullets overpenetrated the target. The 7.65-mm THV bullet produced a lesion which in its extent resembled that of the fully jacketed 9-mm bullet, and should be a suitable alternative for the Danish Police Force. 相似文献