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941.
942.
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   
943.
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   
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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   
947.
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   
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It is well-known that modelers and policy analysts gain access to policymaking arenas based on what they know. Therefore, critics of models are quick to employ various types of technical standards when evaluating policy models in order to assess validity and reliability of claims to knowledge. This article argues that, in the effort to make models better, overreliance on technical standards misses the important political and policy reasons to model: models call attention to the modelers and to their advice about important policy problems of the day. In this sense, models are used as symbols, as claims to authority, whether or not the underlying knowledge is technically up to snuff. Drawing on the experience of energy policy models, this article explores the problem of models as knowledge versus models as symbols and it examines the muddle that conflicts between them produce.  相似文献   
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