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排序方式: 共有410条查询结果,搜索用时 15 毫秒
91.
OBJECTIVE: To evaluate treatment of antebrachial growth deformities (AGD) with a lengthening procedure using a circular external skeletal fixation (CESF) system and to determine prognostic factors. STUDY DESIGN: Prospective clinical study. ANIMALS: Thirty-four dogs with unilateral AGD. METHODS: Length deficits, angular and rotational deformities, elbow incongruity (EI), osteoarthritis (OA) of the elbow and carpal joint, function, and cosmesis were determined before and after a CESF lengthening procedure. RESULTS: On admission, EI (21 dogs; 62%), OA of the elbow joint (17 dogs; 50%), carpal OA (12 dogs; 35%), and concomitant elbow and carpal OA (5 dogs; 7%) were common findings. Treatment significantly improved function (normal, 20 dogs; 60%) and cosmesis (normal, 22 dogs; 65%). Angular and rotational deformities were almost completely corrected with small remaining length deficits. Elbow and carpal OA increased significantly during the follow-up period. Significant correlations were demonstrated between initial elbow OA and final function (R=0.42, P=.02), initial function and final function (R=0.41, P=.02), and initial ulnar and radial deficit and final cosmesis (R=0.58, P=.0001 and R=0.45, P=.008). CONCLUSIONS: Treatment of AGD by a CESF lengthening procedure was successful despite small remaining length deficits. Initial elbow OA, function, and ulnar and radial length deficits are prognostic factors in the treatment of AGD. CLINICAL RELEVANCE: Initial elbow OA and initial function are prognostic factors in predicting the functional outcome of treatment of AGD with a CESF lengthening procedure in the dog. 相似文献
92.
93.
We used factor and path analyses to identify the causal paths or relationships between variables affecting the demand and use by subsistence farmers of the various services offered by government-employed veterinary livestock technicians (VLTs) in Zimbabwe in 1996. We examined whether the farmer had implemented the VLT-recommended livestock-management procedures. Various factors that have been reported or theorised as important in the demand for veterinary services by subsistence farmers are described. The important factors positively affecting whether farmers had sought veterinary assistance in the last 24 months included familiarity of the farmer with the VLT, if situated closer to the VLT’s base, and if the farmer received further training in agriculture (either through courses or from attendance at demonstrations on animal husbandry conducted by the VLT). Factors affecting whether farmers implemented the recommended management practices that had a monetary cost included familiarity with the VLT, proximity to the VLT’s premises, farmer literacy, club membership, and farmer’s wealth. There was a difference in the paths generated for preventive measures that had a monetary cost versus those measures that involved only a labour or effort costs. For the former practices, the VLT played an important role informing farmers by extension and demonstrations, and farmer’s membership of a club increased their performance. 相似文献
94.
Dirk Jan van der Gaag Herman D. Frinking 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(6):573-580
The effects of host plant exudates, light and temperature on germination of oospores of Peronospora viciae f.sp. pisi in vitro were investigated. Seed and root exudates did not increase percentage germination, whereas light inhibited germination. The first germ tubes appeared after 4, 7, and 14 days of incubation at 15, 10 and 5 °C, respectively. The eventual level of germination was highest and had similar values at 5 and 10 °C. At 20 °C germination was poor and at 25 °C no germination was observed. Oospores placed on membrane filters were incubated on soil. When oospores were retrieved from the membrane filters after six days and placed in water at 10 °C, they germinated within 2 days. On soil significantly less oospores germinated than in water. Germinability of oospores stored in the dark at 5 or 20 °C at 30 or 76% RH was studied over a two-year period. Germinability generally increased over time, but fluctuations were observed indicating the occurrence of secondary dormancy. Time courses of germinability were generally similar for oospores stored at several temperatures and humidities. No effect of light on time course of germinability was found when oospores were exposed to alternating light-dark periods or stored in continuous dark for 140 days. Percentage germination observed in a germination assay was correlated with percentage infection determined in a bioassay. 相似文献
95.
Shin-Duk Kim Herman W. Knoche Larry D. Dunkle 《Physiological and Molecular Plant Pathology》1987,30(3)
The cyclic tetrapeptide, cyclo-(-Pro-Ala-Ala-Aoe), which is a host-selective toxin (HC-toxin) produced by the maize pathogen, Helminthosporium carbonum race 1, was reduced with sodium borohydride. Reduction converted the 2-amino-8-oxo-9,10-epoxydecanoic acid (Aoe) residue to a 2-amino-8-hydroxy-9,10-epoxydecanoic acid (Ahe) residue. Two isomers were isolated and shown by NMR to be diastereomers of cyclo-(-Pro-Ala-Ala-Ahe) that differed by their configurations of carbon atom number eight of the Ahe residues. Neither isomer, alone nor as a 1:1 mixture, was toxic to lines of maize sensitive to HC-toxin. Consequently the ketone group of the Aoe residue in HC-toxin appears to be necessary for the toxicity of this host-selective toxin. 相似文献
96.
Boyen F Pasmans F Van Immerseel F Morgan E Botteldoorn N Heyndrickx M Volf J Favoreel H Hernalsteens JP Ducatelle R Haesebrouck F 《Veterinary microbiology》2008,128(3-4):364-373
Virulence genes regulated by the SsrA/B system are indispensable for systemic disease in BALB/c mice. The role of this regulating system in the pathogenesis of Salmonella Typhimurium infections in pigs is not documented. In the present study, the interactions of Salmonella Typhimurium and an ssrA/B mutant were compared in vitro and in vivo. The ssrA/B mutant strain displayed decreased Salmonella Pathogenicity Island 2 (SPI-2) expression levels, showed a replication defect in mouse macrophages and was attenuated in a mouse model after oral inoculation. Using real time qRT-PCR and a porcine ileal loop model, it was shown that the ssrA/B mutant strain was not significantly attenuated in overall virulence and SPI-1 expression in specific. Flowcytometric analysis demonstrated that the ssrA/B mutant strain was defective in intracellular replication in porcine macrophages. After oral inoculation of piglets with the wild type strain or the ssrA/B mutant strain, the animals of both groups excreted Salmonella and were colonized by Salmonella to the same extent. In an intravenous mixed infection model, the ssrA/B mutant strain was defective in the colonization of several internal organs. These results suggest that the ssrA/B gene of Salmonella Typhimurium plays a limited role in the persistent intestinal colonization of pigs. 相似文献
97.
Henryk Zenliski Joanna Honke Agnieszka Troszyska Halina Kozowska 《Cereal Chemistry》1999,76(6):944-948
The purpose of this study was to examine the reduced and oxidized glutathione status of selected cereal grains as a potential index of balance between oxidative stress and antioxidant systems, and the contribution of reduced glutathione to the total antioxidant status in cereal grain extracts. Wheat cultivars Almari and Henika, barley cultivars Gregor and Mobek, rye cultivar Dañkowskie Złote, oat cultivar Sławko, and buckwheat cultivar Kora were used. Total antioxidant status (TAS) was measured by the ABTS (2,2'-azinobis(3-ethyl-benzothiazoline-6-sulphonate)) method. Contents of total phenolic compounds were also determined. Reduced (GSH) and oxidized glutathione (GSSG) (γ-glutamyl-cysteinyl-glycine) were assayed using the spectrofluorimetric method, and results were confirmed by the enzyme recycling method. Correlation coefficient for the GSH/GSSG ratio was r = 0.79. Correlation between TAS and the total phenolic compound content was r = 0.81. Correlation between GSH/GSSG ratio and TAS values was r= 0.46, depending on the extraction system used. The GSH/GSSG ratio may indicate a hierarchy among different cultivars and variance of cereal grains against damage caused by reactive oxygen species. For the main water-soluble antioxidants, our data indicate a potential hierarchy of resistance in investigated cereals against oxidative stress (buckwheat > wheat > barley ≈ rye > oat). This hierarchy was confirmed by the ability of investigated cereal extracts to scavenge superoxide anion radicals in vitro. The reduced-oxidized glutathione status in different cereal grains can be applied as a potential index of balance between oxidative stress and antioxidant systems. 相似文献
98.
The finite element method was used to analyse the cutting process of a sandy loam soil with medium-deep subsoiler, used as a compaction sensor, aiming to calculate the subsoiler draught for various combinations of dry bulk density, moisture content and tillage depth. The finite element results showed that draught increased with depth and dry bulk density, whereas it decreased with moisture content. A multiple linear regression analysis was performed to establish a formula for relating subsoiler draught (dependent variable) with the three independent variables. The regression equation developed was simple and had a high determination coefficient close to 0.95. An equation for prediction of dry bulk density as a function of moisture content, depth and draught was derived from the regression equation developed. This equation was used to calculate dry bulk density, for measured depth, moisture content and draught at nine different points along a single line in a meadow field of a silty clay loam soil. The predicted dry bulk density indicated that there was a considerable variation in the degree of compaction throughout the measured line. However, the on-line depth control and measurement of moisture content still need to be integrated with the on-line measurement of draught, to govern the model suitability for performing on-line detection of the spatial distribution of soil compaction, assessed as dry bulk density. 相似文献
99.
J.A.M. Missotten J. Michiels J. Goris L. Herman M. Heyndrickx S. De Smet N.A. Dierick 《Livestock Science》2007,108(1-3):232-235
In this trial two commercial probiotic products (Bactocell® and Adjulact® Pro) were investigated in vitro for their use as microbial inoculum for the production of fermented liquid feed (FLF) for pigs. Bactocell® was applied at a dose of 9 and 10 log10 CFU/kg and Adjulact® Pro at a level of 9 log10 CFU/kg. The FLF (control and treatments) was prepared with a water to feed ratio of 4:1 and run in batch for 72 h at 30 °C. The microbial population was followed with plate countings and the lactic acid, acetic acid and ethanol concentration was determined at different time points in the FLF. After 24 h, significant differences (P < 0.05) were found between the control and the Adjulact® Pro FLF for pH (4.7 vs 4.3), lactic acid (57.9 vs 91.5 mmol/L), acetic acid (23.1 vs 6.8 mmol/L), ethanol (24.5 vs 1.1 mmol/L), coliforms (7.2 vs 4.3 log10 CFU/mL) and E. coli (6.2 vs 4.4 log10 CFU/mL). Bactocell® addition did not alter the fermentation characteristics compared to the control FLF. After 72 h no significant differences between treatments were noted, except for the yeast count which was higher in the FLF inoculated with Adjulact® Pro. 相似文献
100.