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排序方式: 共有227条查询结果,搜索用时 15 毫秒
21.
NICOLE E. DUFFEE RICHARD F. BEVILL JOHN C. THURMON HERBERT G. LUTHER JR DALE E. NELSON FRANCES E. HACKER 《Journal of veterinary pharmacology and therapeutics》1984,7(3):203-211
The concentration of sulfamethazine in plasma and sulfamethazine and its metabolites in urine were compared in male, female and castrated male swine. A surgical technique for placement of catheters in the urinary bladder was used to facilitate the collection of urine in males and castrated males. The elimination rate of sulfamethazine from plasma and the excretion of parent drug and metabolites into urine did not differ significantly among females, males and castrated male swine. 相似文献
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Fred A. Williams JR DVM Ronald M. Bright DVM MS Diplomate ACVS Gregory B. Daniel DVM MS Diplomate ACVR Kevin A. Hahn DVM PhD Steve A. Patton DVM MS Diplomate ACVP 《Veterinary surgery : VS》1999,28(5):348-354
OBJECTIVE: To determine if once-daily colonic irrigation results in fecal continence for a 24-hour period in dogs with colostomies and if colonic volume increased in response to the irrigation. STUDY DESIGN: A prospective controlled experimental study. ANIMALS: Four intact male and one intact female mixed breed dogs. MATERIALS: All dogs received left end-on paralumbar colostomies. Four dogs received once-daily colonic irrigation for 8 weeks, whereas the control dog did not. Daily fecal weights were recorded for the length of the study in all dogs. Barium enema studies and volumetric studies were used to determine colonic volumes. RESULTS: Daily fecal weights were significantly decreased in treatment dogs compared with the control dog. Colonic volume increased in irrigated dogs in response to daily irrigation over the 8 week period of the study. CONCLUSIONS: Colonic irrigation resulted in significantly decreased fecal production over a 24-hour period. Therefore management of dogs with colostomies would be more practical and cost effective. It did not result in complete fecal continence in this study. Further clinical studies are indicated to determine if longer periods of irrigation would result in complete continence. 相似文献
25.
Abstract This study on reef placement involves two aspects: (1) the development of a bioenergetics model for red snapper, Lutjanus campechanus (Poey), in Gulf of Mexico waters off the coast of Alabama, where significant numbers of artificial reefs are thought to exist, and (2) a fuzzy rough set model by which parameters determined from the bioenergetics model can provide a decision tool for optimally spacing artificial reefs during deployment. The bioenergetics and consumption rates of L. campechanus by age class foraging on artificial reefs in the Gulf of Mexico off the coast of Alabama provided input into the fuzzy rule‐based model. After conducting multiple simulations, highest certainty in optimal reef spacing was achieved for reef distances between 0.50 and 0.95 km such that no more than two fit within a 1‐km2 area. Results can inform fisheries managers about placement of artificial reefs to affect the health and survival of reef‐associated species. 相似文献
26.
C. FERNANDES da SILVA E. BALLESTER J. MONSERRAT L. GERACITANO W. WASIELESKY JR P.C. ABREU 《Aquaculture Nutrition》2008,14(6):507-514
The nutritional quality of biofilm, a microbial community associated to an organic matrix, was evaluated in artificial substrate (polyethylene screen) in net cages during 30 days in the Patos Lagoon estuary, Southern Brazil. During this period, samples of biofilm were collected each 5 days for analysis of chlorophyll a, microorganisms abundance, dry weight, protein and lipid contents. During the study, chlorophyll a varied from 0.38 to 2.75 μg cm?2; dry weight between 7.16 and 17.63 mg cm?2; protein content from 0.43 to 1.76 mg cm?2 and lipid concentration between 1.21 and 4.23 mg cm?2. The variation of lipid in the biofilm was closely related to the abundance of free heterotrophic bacteria (34.25–56.54 × 106 cells cm?2), filamentous cyanobacteria (7.5–15.9 × 106 filaments cm?2), flagellates (6.92–12.89 × 106 cells cm?2) and mainly nematodes (29–1,414 organisms cm?2), while protein content varied similarly to the abundance of unicellular centric diatoms (52.10–179.81 × 103 cells cm?2), and nematodes. This information will allow a better management of food supply to raised aquatic organism with the utilization of natural productivity in the culture systems, with considerable decrease in production costs. 相似文献
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Objective To study the efficacy of multiple striate keratotomy for the treatment of persistent corneal erosions suspected to be caused by primary corneal epithelial basement membrane disease.
Design A retrospective study.
Animals 16 dogs, three cats and one Australian dingo.
Procedure A technique called multiple striate keratotomy was used to treat twenty animals suffering from persistent corneal erosions.
Results All persistent corneal erosions healed with only one treatment. Most cases healed within 2 weeks. One case developed a second erosion in the same eye but in a different position to the original erosion.
Conclusions Multiple striate keratotomy is a safe, effective and well tolerated technique for the treatment of persistent corneal erosions thought to be caused by corneal epithelial basement membrane disease. 相似文献
Design A retrospective study.
Animals 16 dogs, three cats and one Australian dingo.
Procedure A technique called multiple striate keratotomy was used to treat twenty animals suffering from persistent corneal erosions.
Results All persistent corneal erosions healed with only one treatment. Most cases healed within 2 weeks. One case developed a second erosion in the same eye but in a different position to the original erosion.
Conclusions Multiple striate keratotomy is a safe, effective and well tolerated technique for the treatment of persistent corneal erosions thought to be caused by corneal epithelial basement membrane disease. 相似文献
28.
Simulation study of the competitive ability of erect, semi-erect and prostrate cowpea (Vigna unguiculata) genotypes 总被引:1,自引:1,他引:1
Ecophysiological simulation models provide a quantitative method to predict the effects of management practices, plant characteristics and environmental factors on crop and weed growth and competition. The INTERCOM interplant competition model was parameterised, calibrated by monoculture data for three cowpea (Vigna unguiculata) genotypes that differed in growth habit, common sunflower (Helianthus annuus) and common purslane (Portulaca oleracea), and used to simulate competition of cowpea cover crops with sunflower or purslane. The simulation results were compared with observations from field competition experiments in 2003 and 2004. INTERCOM more accurately simulated actual field data for the competition of cowpea genotypes and sunflower than companion field experiments for the competition of cowpea and purslane. The validated simulation model of cowpea and sunflower at two densities was used to study the effects of cowpea growth habit on final biomass production of cowpea and sunflower. The model suggested that erect growth habit was more competitive than semi‐erect and prostrate growth habit, when cowpea genotypes were grown with sunflower. Cowpea leaf area distribution was important to higher cowpea biomass production, while cowpea height growth was important to reduce sunflower biomass. Our simulation approach is suggested as a method for crop breeders to gauge the likely success of selection for competitive crops before undertaking expensive long‐term breeding experiments. 相似文献
29.
A full ophthalmic examination was performed on 40 Siberian husky dogs using direct and indirect ophthalmoscopy, gonloscopy and nasolacrimal cannulation. Eight (20%) of the dogs were found to have distichia, 10 (25%) had excessive medial caruncular hairs, 8 (20%) had absence, displacement, or narrowing of the nasolacrimal puncta, 2 (5%) had bilateral corneal crystalline opacities, and 2 (5%) had unilateral areas of lateral corneal lipidosis. Fifty percent of the dogs had some abnormality of the iridocorneal (drainage) angle. However, in only one of these was the deformity severe enough to require glaucoma prophylaxis. An association between blue iris colour and malformation of the iridocorneal angle was noted. 相似文献
30.
本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化 相似文献