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1.
Freshly harvested equine skin incised with an electrosurgical unit, a radiosurgical device, or a carbon dioxide (CO2) laser was examined by light microscopy to determine the extent of thermal injury caused by each instrument. There was no significant difference between the thermal injury caused by the electrosurgical unit in the pure-cut mode and the CO2 laser in the superpulse mode, or between the electrosurgical unit and the radiosurgical device in the fully filtered cut mode. However, thermal injury caused by the CO2 laser was significantly less than that caused by the radiosurgical device. The amount of thermal injury in this in vitro study was similar to that found in vivo with other species.  相似文献   
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Objective To compare cortisol responses to three corticotrophic preparations in normal dogs.
Animals Eight clinically normal dogs (four intact males, four intact females) of medium size.
Procedures Each dog received four treatments on four separate occasions in a duplicated Latin square pattern. Treatments were two adrenocorticotrophin (ACTH) preparations given intramuscularly at 2.2 U/kg, one of the ACTH preparations given intramuscularly at 1 U/kg and a synthetic polypeptide with ACTH-like activity (tetracosactrin, cosyntropin) given intravenously at 5 μg/kg. Plasma samples were taken for cortisol assay before and at 0.5, 1, 2 and 4 h after treatment.
Results Plasma cortisol concentrations were similar with the two ACTH preparations and at both dose rates. Tetracosactrin produced smaller mean peak cortisol concentrations, which tended to occur earlier than with ACTH, and smaller values for the area under the curve of plasma cortisol concentration from zero time to 4 h.
Conclusion The findings suggest that canine adrenal function can be tested adequately by giving ACTH intramuscularly at 1 U/kg and measuring plasma cortisol in samples taken at 0 and 2 h, or by giving tetracosactrin intravenously at 5 μg/kg and determining cortisol concentration at 0 and 1 h.  相似文献   
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The graphical presentation of the results of complex computer model calculations is frequently as important as the computation, since it is generally through such presentations that the modeler and the modeler's audience derive the maximum amount of information. In this article graphical techniques for presenting multidimensional model results are reviewed and examples are given of the most useful forms of presentation. Color graphics is used increasingly for the presentation of model results, and three types of color displays are discussed here: the chromatic plot, the binary chromatic plot, and the ternary chromatic plot. Their use is illustrated with examples from computer modeling of air quality in the urban atmosphere.  相似文献   
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Judged association between two variables represented on scatterplots increased when the scales on the horizontal and vertical axes were simultaneously increased so that the size of the point cloud within the frame of the plot decreased. Judged association was very different from the correlation coefficient, r, which is the most widely used measure of association.  相似文献   
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Altimetry and radar scattering data for Venus, obtained from 10 of the first 13 orbits of the Pioneer Venus orbiter, have disclosed what appears to be a rift valley having vertical relief of up to 7 kilometers, as well as a neighboring, gently rolling plain. Planetary oblateness appears unlikely to exceed 1/2500 and may be substantially smaller.  相似文献   
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Three large Venus surface features, identified previously in images obtained from Earth-based radar observations, are shown by the Pioneer Venus radar mapper to be elevated 5 to 10 kilometers above the surrounding terrain. Two of these features, one bright and the other dark, lie adjacent to each other astride the 65 degrees N parallel between longitudes 310 degrees E and 10 degrees E. The combined region forms a huge tectonically uplifted plateau, surmounted by radar-bright ridges that may have either a volcanic or tectonic origin. The third feature, located at 30 degrees N, 283 degrees E, is radar-bright and may consist of volcanic material extruded along a fault zone. A first radar-scattering image, compiled from data obtained by the mapper in its imaging mode, shows a region north of the equator; several circular depressions seen in this area may result from meteoritic impact.  相似文献   
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This study was conducted to examine the hypothesis that slow N mineralization and associated organic matter accumulation in Andept, was related to the internal N cycling regime, and if so, to determine at what stage.The results indicated that N was mineralized from native organic matter in an Andept less rapidly than occurred in a Mollisol of similar organic matter content but N mineralization from added alfalfa was similar in both soils. Both soils immobilized N rapidly in the presence of glucose, but remineralization of immobilized N was more rapid in the Mollisol than in the Andept samples. Partial sterilization resulted in substantial remineralization of N from both soils.It was concluded that slow N mineralization in the Andept soil is due to slow N recycling from recently synthesized biomass. Associated with this is a low supply of soluble C in the Andept soil. Whether slow N recycling from recently synthesized biomass results from some toxic effect on predatory organisms, from lytic enzyme adsorption, adsorption of lytic products or some mineral nutrient deficiency awaits further study.  相似文献   
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Seventy-nine diarrheic calf fecal samples were examined by electron microscopy, immunodiffusion and the fluorescent antibody technique for the presence of rotavirus (reovirus-like agent). Thirty-eight (48%) of the samples were positive by electron microscopy, 59% by immunodiffusion and 20% positive by fluorescent antibody technique analyses. Another 9% were suspect-positive by fluorescent antibody technique. Chymotrypsin treatment of the fecal samples increased the ease of observing the viral particles by electron microscopy and also intensified the immunodiffusion arcs obtained. Immunodiffusion analyses using specific antisera to the virus would appear to be a practical method of detecting rotavirus in diarrheic fecal samples.  相似文献   
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