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1.
AIMS: To determine the pharmacokinetics, and anaesthetic and sedative effects of alfaxalone after I/V and I/M administration to cats.

METHODS: Six European shorthair cats, three males and three females, with a mean weight of 4.21 (SD 0.53) kg and aged 3.8 (SD 0.9) years were enrolled in this crossover, two–treatment, two-period study. Alfaxalone at a dose of 5?mg/kg was administered either I/V or I/M. Blood samples were collected between 2–480 minutes after drug administration and analysed for concentrations of alfaxalone by HPLC. The plasma concentration-time curves were analysed by non-compartmental analysis. Sedation scores were evaluated between 5–120 minutes after drug administration using a numerical rating scale (from 0–18). Intervals from drug administration to sit, sternal and lateral recumbency during the induction phase, and to head-lift, sternal recumbency and standing position during recovery were recorded.

RESULTS: The mean half-life and mean residence time of alfaxalone were longer after I/M (1.28 (SD 0.21) and 2.09 (SD 0.36) hours, respectively) than after I/V (0.49 (SD 0.07) and 0.66 (SD 0.16) hours, respectively) administration (p<0.05). Bioavailability after I/M injection of alfaxalone was 94.7 (SD 19.8)%. The mean intervals to sternal and lateral recumbency were longer in the I/M (3.73 (SD 1.99) and 6.12 (SD 0.90) minutes, respectively) compared to I/V (0 minutes for all animals) treated cats (p<0.01). Sedation scores indicative of general anaesthesia (scores >15) were recorded from 5–15 minutes after I/V administration and deep sedation (scores 11–15) at 20 and 30 minutes. Deep sedation was observed from 10–45 minutes after I/M administration. One cat from each group showed hyperkinesia during recovery, and the remainder had an uneventful recovery.

CONCLUSIONS AND CLINICAL RELEVANCE: Alfaxalone administered I/V in cats provides rapid and smooth induction of anaesthesia. After I/M administration, a longer exposure to the drug and an extended half life were obtained compared to I/V administration. Therefore I/M administration of alfaxalone could be a reliable, suitable and easy route in cats, taking into account that alfaxalone has a slower onset of sedation than when given I/V and achieves deep sedation rather than general anaesthesia.  相似文献   
2.
畜产品安全中存在的问题与分析   总被引:1,自引:0,他引:1  
阐述了我国畜产品安全现状,强调了其形势的严峻性和紧迫性,分析了当前存在的主要问题,并提出了改进措施和建议。  相似文献   
3.
Phellinus torulosus was reported for the first time on Cupressus sempervirens in Tuscany, Italy. This fungus causes white rot in roots and stems and may also invade and kill the cortical tissue. The invasion of trees by the fungus and its subsequent spread is probably facilitated by fire scars.  相似文献   
4.
We assessed the mycelial growth rate of Hymenoscyphus fraxineus, the causal agent of ash dieback, on agar media containing leaf extracts of seven common Mediterranean species of the Oleaceae (Fraxinus excelsior, F. angustifolia, F. ornus, Ligustrum vulgare, Olea europaea, Phyllirea latifolia and Syringa vulgaris). The pathogen grew on all media, but growth rates showed significant differences among media and H. fraxineus isolates. Growth rates were highest on media containing F. excelsior and F. angustifolia, intermediate on media containing O. europaea and P. latifolia and lowest on those containing F. ornus and L. vulgare.  相似文献   
5.
The paper examines water use in industrial production as a cause of geographical clustering of major air polluting industries. It shows that the majority of particulate and sulfur oxide emissions in the State of Illinois is emitted by industries using more than five billion liters of water per establishment per year. It also shows that the majority of industrial air pollutants is emitted within urban areas which are on water bodies with high and consistent volumes of water available. These and other results cited in the paper imply that any policy directly or indirectly promoting geographic dispersal as a means of reducing air pollution concentrations and population exposure rates is likely to be limited in effectiveness. It is suggested that such a policy can be effective only if at least one of two specified conditions is met. However, these conditions do not, by themselves, insure the success of such a policy. Finally, it is observed that the conjunction of air pollution with industrial water use indicates that much closer attention is needed to the relationship between air pollution and water pollution policies.  相似文献   
6.
Abstract

New studies are needed to optimize the nitrogen (N) amount that can be applied to utilize the Azospirillum brasilense benefits. In addition, information regarding the interaction between the urease inhibitor and biological nitrogen fixation (BNF) and how they affect the macronutrients accumulation are also needed. We evaluate the effect of N sources and doses associated with A. brasilense regarding the macronutrients accumulation in straw and grains and wheat grain yield in tropical conditions. A randomized block experimental design was used with four replications in a 2?×?5?×?2 factorial arrangement as follows: two N sources (urea and urea with urease enzyme inhibitor NBPT; five N doses (0, 50, 100, 150, and 200?kg ha?1) applied in topdressing; with and without A. brasilense inoculation. We found that an increase in N doses positively influenced the accumulation of macronutrients in straw and grains and the wheat grain yield. N sources have similar effects. Inoculation with A. brasilense increased accumulation of Mg and S in straw and P, Ca, and Mg in grains, regardless of the N dose. The inoculation with A. brasilense associated with 140?kg ha?1 of N increased wheat grain yield. The inoculation can contribute in a more sustainable way to wheat nutrition and optimizing N fertilization.  相似文献   
7.
Numerical models for the simulation of soil water processes can be used to evaluate the spatial and temporal variations of crop water requirements; this information can support the irrigation management in a rationale usage of water resources. This latter objective requires the knowledge of spatially distributed input parameters concerning vegetation status, soil hydraulic behaviour and groundwater interaction. This task can be achieved by a conjunctive use of remote sensing techniques, geographical information systems and hydrological simulation models. The present work focuses on the criteria applied for the implementation of a one-dimensional model for water flow in each parcel of an irrigation district in southern Italy having extension of 3000 ha.  相似文献   
8.
Ceratocystis platani was detected at several locations in the European side of Istanbul, causing severe dieback and mortality, mainly on Platanus × acerifolia imported from Italy approximately 160 years ago, but also on Platanus orientalis. In the work reported here, the causal agent of the dieback and mortality was identified based on morphological characteristics in culture and internal transcribed spacer (ITS) sequencing, confirming the presence of C. platani in Turkey. All analysed C. platani isolates from Istanbul shared the same ITS sequence with European C. platani strains available in the NCBI, but differed from other species previously ascribed to the Ceratocystis fimbriata species complex. Pathogenicity of C. platani was proven by inoculation onto 25‐cm‐long and 4–9 mm diam. P. orientalis twigs and the causal agent reisolated from symptomatic tissues. In a survey of 976 Platanus in streets and parks of Istanbul, 26.5% of trees showed symptoms of C. platani infections, whilst 5.6% were dead. The proportion of symptomatic trees was higher where management interventions, such as topping or pruning and felling infected trees had been carried out.  相似文献   
9.
Soya and soybean products used in swine feeding contain genistein, a non‐steroidal phyto‐oestrogen which has been demonstrated to influence endocrine functions. This observation leads us to design this study to evaluate the effect of genistein on swine granulosa cell steroidogenesis and proliferation. In the attempt to unravel the genistein signal transduction mechanisms, we verified the effect of lavendustin, a Tyrosine Kinase (TK) inhibitor, and the potential involvement of NO/cGMP pathway. Finally, as angiogenesis is essential for follicle development, we tested the effect of the phyto‐oestrogen on vascular endothelial growth factor production and on granulosa cell redox status, because free‐radical species modulate neovascularization. Our data provide evidence that genistein interferes with granulosa cell steroidogenesis while it does not modulate cell growth: this effect could be at least partially produced by inhibiting TK‐dependent signalling systems. On the contrary, NO/cGMP pathway or vascular endothelial growth factor production can be excluded as signalling mechanism involved in phyto‐oestrogen effects. Remarkably, genistein stimulates hydrogen peroxide production thus potentially inhibiting follicular angiogenesis. Collectively, these results suggest that genistein consumption could potentially negatively impact swine reproductive function.  相似文献   
10.
Five diploid hybrid families derived from crosses between haploids of three Argentinian cultivars and three diploid wild species,Solanum gourlayi, S. chacoense andS. spegazzinii, were evaluated in a field experiment in Balcarce. All plants were androsterile and, thus, could not be screened for 2n pollen production. Data on agronomic tuber traits were statistically analyzed. Differences among families were non-significant for tuber number/plant, but were significant for tuber weight/plant and dry matter content (with values above 21.0% in two of them). The relative frequencies of tubers in the categories established for size, skin texture, and eye depth were family dependent, but they were familiy independent in the categories established for tuber shape and skin color. Great morphological variability was detected for all the traits studied, and plants with high yield and high dry matter content were identified. These families can be used as sources of germplasm in breeding and to explore heterotic responses in 2x × 4x crosses, given the capacity of some plants to produce 2n eggs, as found in a related investigation.  相似文献   
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