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71.
A novel endoscopic approach for the removal of nasal polyps from a cat with upper respiratory obstruction is described. The cat's small oral cavity prevented polyp removal via traditional nasopharyngoscopy and the owner declined rhinotomy because of concerns about postoperative morbidity. Access to the nasopharynx was achieved by introducing an endoscope via gastrotomy and passing the instrument orad through the esophagus into the nasopharynx. Compared with traditional endoscopic approaches, this approach provided superior exposure of the nasopharynx and facilitated use of a larger scope and instruments than would have been possible using retroflexed nasopharyngoscopy. Multiple polyps were readily removed using this approach. The procedure was well tolerated, with minimal surgical morbidity.  相似文献   
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An experiment was conducted using three related wheat (Triticum aestivum L.) genotypes grown on two different soil types (a grey vertosol and a red kandosol) using two different tillage practices (complete and zero) to test the effects of environmental influence on grain quality. Wheat grains from plants grown in each environment were milled into flour; protein and starch were analyzed. The soil type had the biggest impact on both protein and starch content, with the grains from the grey vertosol soil having higher total, insoluble, and soluble protein contents, and lower starch content and flour swelling values. When protein was analyzed using SDS‐PAGE, the major difference observed between grains from the two soil types was an increased intensity of polypeptide bands corresponding to β‐amylase in grains from plants grown on grey vertosol soils.  相似文献   
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Current atmospheric models underestimate the production of organic acids in the troposphere. We report a detailed kinetic model of the photochemistry of acetaldehyde (ethanal) under tropospheric conditions. The rate constants are benchmarked to collision-free experiments, where extensive photo-isomerization is observed upon irradiation with actinic ultraviolet radiation (310 to 330 nanometers). The model quantitatively reproduces the experiments and shows unequivocally that keto-enol photo-tautomerization, forming vinyl alcohol (ethenol), is the crucial first step. When collisions at atmospheric pressure are included, the model quantitatively reproduces previously reported quantum yields for photodissociation at all pressures and wavelengths. The model also predicts that 21 ± 4% of the initially excited acetaldehyde forms stable vinyl alcohol, a known precursor to organic acid formation, which may help to account for the production of organic acids in the troposphere.  相似文献   
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Landscape Ecology - Ecological design used for stormwater management—referred to as Water Sensitive Urban Design (WSUD)—exemplifies how urban environments can benefit from mimicking...  相似文献   
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Fumonisin B(1) (FB(1)) is a water-soluble mycotoxin produced by Fusarium verticillioides. Our research objectives were to determine the leaching of FB(1) through soils and FB(1) binding in soil. Leachate columns were used to determine the movement of FB(1) through soil. FB(1)-contaminated corn screenings or water extracts containing FB(1) were placed on the surface of soil columns. In 100% sand columns, FB(1) leaching was only slightly retarded, whereas at 50%, 75%, and 100% Cecil sandy loam, approximately 60%, 50%, and 20% of the FB(1) was recovered in the column leachate, respectively. The FB(1) retained on the 100% Cecil sandy loam column was tightly bound. However, approximately 75% of the bound FB(1) was released with 5% formic acid and 5% formic acid/acetonitrile (1:1), indicating that the nature of the interaction was probably ionic. The results suggest that FB(1) is quite stable in soils and, while tightly bound, under certain environmental conditions could be released.  相似文献   
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Fumonisins are mycotoxins produced by Fusarium verticillioides (=F. moniliforme) and other Fusarium species. They are found in corn and corn-based foods. Cooking decreases fumonisin concentrations in food products under some conditions; however, little is known about how cooking effects biological activity. Baked cornbread, pan-fried corncakes, and deep-fried fritters were made from cornmeal that was spiked with 5% w/w F. verticillioides culture material (CM). The cooked materials and the uncooked CM-spiked cornmeal were fed to male rats (n = 5/group) for 2 weeks at high (20% w/w spiked cornmeal equivalents) or low (2% w/w spiked cornmeal equivalents) doses. A control group was fed a diet containing 20% w/w unspiked cornmeal. Toxic response to the uncooked CM-spiked cornmeal and the cooked products included decreased body weight gain (high-dose only), decreased kidney weight, and microscopic kidney and liver lesions of the type caused by fumonisins. Fumonisin concentration, as determined by HPLC analysis, in the 20% w/w pan-fried corncake diet [92.2 ppm of fumonisin B(1) (FB(1))] was slightly, but not statistically significantly, lower than those of the 20% w/w baked cornbread (132.2 ppm of FB(1)), deep-fried fritter (120.2 ppm of FB(1)) and CM-spiked cornmeal (130.5 of ppm FB(1)) diets. Therefore, baking and frying had no significant effect on the biological activity or concentration of fumonisins in these corn-based products, and the results provided no evidence for the formation of novel toxins or "hidden" fumonisins during cooking.  相似文献   
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