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51.
Reduction of the overwintering powdery mildew fungus Podosphaera leucotricha resulted from one application of a variety of surfactants (at 50 g/litre a.i.) to apple trees during the dormant season. Examples of non-ionic, anionic and cationic materials were tested and some gave promising control. Successful treatments delayed bud burst during the following spring and caused some loss in fruit yield. 相似文献
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Serial angiography was used to determine blood flow patterns to the penis of rams and bucks. Animals were anesthetized and the internal pudendal artery was catheterized so that contrast medium could be injected toward the crus penis area. By comparing vascular patterns of the ram and buck during erection, it was found that flow patterns of the corpus cavernosum penis (CCP) and corpus spongiosum penis (CSP) were similar for both species. Contraction of the ischiocavernosus muscles occluded the arterial inflow and venous outflow to the CCP, making it a closed system during peak erection. However, during erection, the contrast medium continued to flow into the CSP, showing that it is not a closed system. In the vasodilatation phase, the CSP usually filled before and more intensely than did the CCP. 相似文献
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The metabolism of [14C]triadimefon, triadimenol, diclobutrazol, and the oxo-analogue of diclobutrazol by the basidiomycete fungi Coriolus versicolor and Rhizoctonia solani was studied. Reduction of >C = 0 to >CHOH (activation) was more important for triadimefon than oxo-diclobutrazol. Conversely, oxidation of >CHOH to >C = 0 (deactivation) occurred to a greater extent with diclobutrazol than triadimenol. Formation of primary alcohol metabolites, a possible detoxication route, occurred more with diclobutrazol and its oxo-analogue than with triadimefon and triadimenol. The implications of the reduction/oxidation processes and primary alcohol formation on fungitoxicity of the applied triazolymethane are discussed. The enantiomeric composition of metabolically produced triadimenol is discussed in relation to the in vitro activity of triadimefon supplied against each fungus. 相似文献
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Burkholder WJ Lees GE LeBlanc AK Slater MR Bauer JE Kashtan CE McCracken BA Hannah SS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(2):165-175
Young adult heterozygous (carrier) female dogs with X-linked hereditary nephropathy (XLHN) have glomerular proteinuria but are otherwise healthy. Because data regarding dietary influences on the magnitude of proteinuria in dogs with spontaneous glomerular disease are not available, 12 such dogs were studied in a double crossover experiment intended to determine effects of altering dietary protein intake for up to 6 weeks. Dogs were blocked by urine protein : creatinine ratio (UPC) and randomly assigned to receive 2 diets: high protein (34.6% dry matter [DM], HP) or low protein (14.1% DM, LP) fed in HP-LP-HP or LP-HP-LP sequence. Food intake was measured daily, body weight (BW) was measured twice weekly, and UPC, plasma creatinine, blood urea nitrogen, phosphorus, albumin, and protein concentrations were measured at 2-week intervals. Nutrient digestibility was measured during the third treatment period. Diet had a significant effect (P < .0001) on all measured variables except plasma phosphorus (P > .5), but unintended differences in digestibility of protein and energy (P < or = .01) prevented assignment of the diet effect exclusively to protein. Proteinuria was greater (UPC 4.7 +/- 2.2 versus 1.8 +/- 1.1, P < .0001) when the HP diet was fed, but the LP diet did not maintain starting BW or plasma albumin concentration within the normal reference range. Diet greatly affects the magnitude of proteinuria in XLHN carrier females. Dietary protein restriction can reduce proteinuria in dogs with glomerular disease, but BW and blood protein concentrations may not be maintained if the restriction is too severe. 相似文献
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Lane VM Villarroel A Wetzlich SE Wetzlich S Clifford A Taylor I Craigmill AL 《Journal of veterinary pharmacology and therapeutics》2004,27(4):191-196
Pharmacokinetic parameters of florfenicol were determined in 10 adult sheep (five wethers and five ewes) after a single 40 mg/kg intravenous (i.v.) dose, and three daily subcutaneous (s.c.) doses of 40 mg/kg of a commercial preparation (Nuflor((R))). The concentration of florfenicol in serum samples was assayed using a proprietary HPLC assay method, and pharmacokinetic parameters derived for individual animal data by each route using compartmental and noncompartmental approaches. Two animals (one male and one female) were excluded due to observed i.v. dosing problems, and a biexponential model was found to fit the i.v. data well for six of the other eight animals. Data from two males showed prolonged low concentrations of florfenicol in serum and were better fit by a three-compartment model. The mean +/- SD for the half-lives of the distribution and elimination phases for the six sheep best fit with a two-compartment model were 0.069 +/- 0.018 and 1.01 +/- 0.09 h respectively, and for the V(d(ss)) and clearances were 0.503 +/- 0.035 L/kg and 366 +/- 53 mL/h/kg respectively. The data collected during the s.c. multiple dose study were analyzed using noncompartmental methods only. The bioavailability (F%) after s.c. dosing was calculated in three ways to compare estimation methods as steady-state had not been reached and single dose s.c. data were not obtained past 24 h. Using the AUC(0--24) and AUC(0--> infinity ) from the first dose, the F% values averaged 27 and 40% respectively. Using the AUC(0--> infinity ) for all doses, the F% was 65%. Calculations of the mean time during which the serum concentration exceeded 0.5 and 1.0 microg/mL were 105 +/- 3.9 and 74.7 +/- 12.2 h respectively. 相似文献
59.
OBJECTIVE: To radiographically evaluate the Zurich cementless total hip (ZCTH) cup and correlate lucency with clinical signs of implant instability, time since surgery, and implant generation, using zonal analysis. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned dogs (n = 53). METHODS: Radiographs of dogs that had ZCTH arthroplasty (>1 year) were evaluated using zonal analysis, for lucency surrounding the cup-bone interface (number of zones, length, area). Dogs were examined for clinical signs of implant instability (lameness, hip pain). Lucency was correlated with lameness, time after surgery, and implant generation. RESULTS: Radiographs of 68 implants (18 generation I, 50 generation II) were evaluated. Eight dogs were lame (11.8%). Dogs with lameness were more likely to have lucency in > or =2 zones of analysis (per view), have >2 times the average curvilinear length of lucency, and have >4 times the average area of lucency surrounding the implant compared with non-lame dogs. A weak relationship was observed between time after surgery and implant generation; however, there was no relationship between time after surgery and lucency. CONCLUSIONS: Dogs with lameness after ZCTH arthroplasty were more likely to have lucency at the cup-bone interface. Lucency was better evaluated by radiographic projection than zonal analysis. Temporal progression of lucency was weakly correlated with implant generation. CLINICAL RELEVANCE: Dogs with lucency in > or =2 zones of analysis should be evaluated more frequently for clinical signs of implant loosening. Further investigation of serial radiographs after ZCTH arthroplasty is warranted. 相似文献
60.
Goudey CA 《Science (New York, N.Y.)》2006,314(5807):1875-6; author reply 1875-6