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41.
To assess the effect of human interferon-alpha (IFNα) on shipping fever of Thoroughbred racehorses subjected to long-distance transportation, an IFNα preparation was orally administered to 48 horses three times (once daily, 3 successive days) before transportation (IFNα group). In the control group (25 horses), maltose was administered in the same way. These treatments induced no abnormal findings in Thoroughbred racehorses before transportation. Immediately after transportation, significant increases in rectal temperature were observed in both treatment groups, whereas the rectal temperature of the IFNα group tended to be lower than that of the control group. Although WBC, Fbg, and SAA immediately after transportation were significantly increased due to transportation in both groups, the extent of the increases in the IFNα group was significantly smaller than in the control group. Long-distance transportation had a relatively profound impact on Thoroughbred racehorses, which was mitigated by IFNα treatment.  相似文献   
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喷蒸真空热压技术   总被引:7,自引:0,他引:7  
喷蒸真空热压系在板的热压周期中,通过向板坯内部注入高温高压蒸汽以加速热固性树脂固化,并借助真空处理帮助残余蒸汽和其它有害气体排除、降低板鼓泡发生率的一种热压方法。该技术可有效缩短厚板的热压时间,并改善板的尺寸稳定性、控制板的密度分布、减少砂光损失。喷蒸真空热压技术有望成为木质刨花板和木质复合板热压的发展方向。  相似文献   
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Currently, there is an increasing interest in shipping live adult scallops to markets and broodstock to hatcheries; nevertheless, information about the shipping effect on live scallops physiology is very scarce. In a previous study, a method in emersion was developed to ship scallop seed out of water, but it was not known whether this method is useful to transport adult organisms. As a consequence, the purpose of this study was to evaluate the effects of transportation by the emersion method on the physiological status of the adductor muscle of adult giant lion's paw scallop. Live specimens were packaged in a container and transported in emersion for 11 h. Six scallops were frozen in a farm and a similar number were frozen as soon as they arrived to the laboratory. Physiological indices were determined in each lot and the survival was estimated 24 h after re‐immersion. As a result of the transportation, a significant loss (P<0.05) of total carbohydrates, glycogen, adenosine 5′‐triphosphate and adenilated energetic charge, and a significant increase (P<0.05) in the free amino acids concentration were observed. Eighty‐eight per cent survival was achieved; therefore, we conclude that this method is appropriate for shipping live adult scallops of Nodipecten subnodosus.  相似文献   
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Conidia of the fungus Metarhizium flavoviride were formulated in a paraffinic oil, ‘Shellsol’ T, and sprayed using the Francome MkII exhaust nozzle sprayer. Germination of the conidia collected from the spray was reduced by 30% as compared to unsprayed conidia. However, in bioassays, there was no detectable difference in virulence with conidia collected from the spray samples and unsprayed formulation. This indicated that, despite the recorded reduction in the concentration of active conidia, the efficacy of the formulation remained unchanged after passing through the exhaust nozzle sprayer. The droplet size spectra produced by the sprayer were investigated using the Malvern series 2600cc particle size analyser. The optimum droplets for locust control produced by this sprayer were generated by the number 1 nozzle (internal diameter 2·5 mm) with the number 1 restrictor ring (internal diameter 12.5 mm) sprayed at a pressure of 0·2 bar. The droplets thus produced had a volume median diameter of 58 μm when the nozzle protruded between 1 and 2 mm above the level of the restrictor ring. Of the droplets in the spray plume created by these conditions, 33% were between 50 and 100 μm, a range recommended as an achievable optimum for the ultra-low-volume application of Metarhizium flavoviride. The role of the exhaust nozzle sprayer as a tool for the application of M. flavoviride for locust control is discussed with reference to other vehicle-mounted ultra-low-volume sprayers. © 1997 SCI  相似文献   
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通过施粉后粮库内采样,实验室培养,检查试虫死亡率的方法,对比了平房仓内横向通风系统下,利用环流与直排两种惰性粉气溶胶施粉方式的防虫效果。结果表明:两种方式都能使惰性粉气溶胶贯穿粮堆,形成最低致死浓度,对长角扁谷盗、玉米象、谷蠹和赤拟谷盗均能起到一定的防治效果,环流施粉好于直排施粉,在惰性粉分布的均匀性上,两者均没有表现出明显的优势。  相似文献   
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姜耀华  顾明  曹阳  王斌 《农业工程学报》2009,25(12):124-127
为了实现发动机电子控制系统对空燃比的精确反馈控制和方便对发动机进行诊断等用途,在熟悉宽域氧传感器工作原理的基础上,设计了空燃比采集显示系统和PC监控系统。并对测试系统的输出电压和混合气的过量空气系数的对应关系进行了试验标定,最后在发动机试验台架上该测试系统进行了试验验证。结果表明该系统灵敏度高、响应时间短(100 ms),采集数据显示直观,可用于发动机空燃比闭环控制和车载自动诊断系统(OBD)等的开发。  相似文献   
49.
通过对港口企业和船公司盈利的分析,提出了双方博弈的基础.通过建立不完全信息条件下的博弈模型,以港口企业先行动博弈为前提,得出双方的均衡解,从而确定港口的最佳费收,最后,通过算例对本模型进行分析.  相似文献   
50.
高功率密度柴油机的排气流通特性   总被引:1,自引:1,他引:0  
为了分析柴油机功率密度提高后排气流动特征的变化,建立单缸柴油机一维热动力模型,对转速为3000r/min时柴油机的控制参数和热动力参数进行仿真,计算结果与试验值吻合良好。应用校准的模型分析柴油机提高功率密度对排气流动的影响。结果表明,随转速提高超临界排气持续曲轴转角明显增加,在转速为4200r/min时达128°;活塞排气指示功明显增大。排气流通面积成为影响高功率密度柴油机排气流动性能的主要因素,增大排气门喉口直径,可缩短超临界排气,减小排气指示功绝对值。为高功率密度柴油机排气系统的优化设计提供理论参考。  相似文献   
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