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Danyi S Widart J Douny C Dang PK Baiwir D Wang N Tu HT Tung VT Phuong NT Kestemont P Scippo ML 《Journal of veterinary pharmacology and therapeutics》2011,34(2):142-152
Determination and kinetics of enrofloxacin and ciprofloxacin in Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a liquid chromatography/mass spectrometry method. J. vet. Pharmacol. Therap. 34, 142-152. The fluoroquinolones enrofloxacin (EF) and ciprofloxacin (CF) residues were investigated in the edible tissues of two important Asian aquacultured species such as Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry method. Fish and prawn were treated with medicated feed with multiple doses of EF, in field conditions. A validation study of the analytical method was realized in terms of linearity, specificity, precision (repeatability and within-laboratory reproducibility), recovery and decision limit (CCα). The time needed before the antibiotic disappears from animal tissues or reach the maximum residue limit (MRL, 100μg/kg) was assessed. The concentration values of EF detected in Tra catfish tissue were between the MRL and 2×MRL concentrations, according to the fish density, 7days following the end of the enrofloxacin treatment (20mg/kg body weight per day, for seven consecutive days). The concentration value of ER in prawn tissue was lower than the MRL and the limit of quantification (LOQ, 14μg/kg) 5 and 7days after the stop of the EF treatment (50mg/kg body weight per day, for five consecutive days), respectively. The mean detected levels of CF was much lower in comparison with that of EF, indicating that only a small part of EF is metabolized into CF (<5%) in both Tra catfish and prawn. 相似文献
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将狂犬病病毒糖蛋白cDNA BglⅡ(1.67kb)片段正向插入pMT010/A^+BamHⅠ切点,构建重组质粒pMT010/A^+-Rgp,用EcoRⅠ+SalⅠ对pMT010/A^+-Rgp进行双酶切后,回收含有狂犬病病毒糖蛋白cDNA和绵羊MT启动子的2.76kb片段,通过显微注射技术将该片段注入小鼠单细胞受精卵雄前核内,在进行胚胎移植后,获得44只小鼠,经PCR、Southern杂交及原位 相似文献
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简述了新媒体和复杂自适应系统(CAS)理论的相关概念,辨析了传统科普和新媒体时代科普的不同,指出了新媒体时代的科普系统是CAS ,提出了用CAS理论指导新媒体时代科普工作的几点原则。 相似文献
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Nicholas A Lyons Neal Alexander Katharina DC St?rk Thomas D Dulu Jonathan Rushton Paul EM Fine 《Veterinary research》2015,46(1)
Foot and mouth disease (FMD) is a highly transmissible viral infection of cloven hooved animals associated with severe economic losses when introduced into FMD-free countries. Information on the impact of the disease in FMDV-endemic countries is poorly characterised yet essential for the prioritisation of scarce resources for disease control programmes. A FMD (virus serotype SAT2) outbreak on a large-scale dairy farm in Nakuru County, Kenya provided an opportunity to evaluate the impact of FMD on clinical mastitis and culling rate. A cohort approach followed animals over a 12-month period after the commencement of the outbreak. For culling, all animals were included; for mastitis, those over 18 months of age. FMD was recorded in 400/644 cattle over a 29-day period. During the follow-up period 76 animals were culled or died whilst in the over 18 month old cohort 63 developed clinical mastitis. Hazard ratios (HR) were generated using Cox regression accounting for non-proportional hazards by inclusion of time-varying effects. Univariable analysis showed FMD cases were culled sooner but there was no effect on clinical mastitis. After adjusting for possible confounders and inclusion of time-varying effects there was weak evidence to support an effect of FMD on culling (HR = 1.7, 95% confidence intervals [CI] 0.88-3.1, P = 0.12). For mastitis, there was stronger evidence of an increased rate in the first month after the onset of the outbreak (HR = 2.9, 95%CI 0.97-8.9, P = 0.057).
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-015-0173-4) contains supplementary material, which is available to authorized users. 相似文献9.
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The aim of the study was to determine identification, three-dimensional modelling, and morphometry of intracranial arteries in New Zealand Rabbit by using computed tomography angiography. A total of 20 adult New Zealand Rabbits from both sexes were used in the study. General anaesthesia procedure was followed before computed tomography angiography imaging. Rabbits were placed in a prone position for imaging. Computed tomography angiography imaging was performed by injecting contrast agent into vena auricularis marginalis of rabbits. Morphometric measurements of the specified points were taken by MIMICS program using the computed tomography angiography images acquired. Three-dimensional intracranial artery model was prepared from the two-dimensional images on the same program. Measurements were statistically compared in terms of sex and side. It was observed in the study that arteria basilaris was generated by bilateral arteria vertebralis at the basal level of medulla oblongata. In the study, a statistically significant difference was determined only in diameter values of arteria cerebri caudalis dextra et sinistra in both female and male rabbits. On the other hand, no statistically significant difference was determined with respect to the side. Consequently, we think that the data of the present study will contribute to further studies on cerebrovascular pathology, clinicians or researchers. 相似文献