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81.
肉鹅H5亚型禽流感疫苗免疫效果的研究   总被引:2,自引:0,他引:2  
选用H 5亚型禽流感油乳剂灭活疫苗(H 5N 1,R e1株)对马岗鹅作首免日龄、免疫次数与免疫剂量的免疫试验。结果表明,雏鹅在7、14或21日龄作1次免疫均产生免疫应答,其中14与21日龄免疫组免疫后第5周抗体水平均达4 log2以上,抗体动态变化均值与峰值均高于7日龄免疫组2~3个滴度。用0.5、1和2 m l/只3个剂量对14日龄雏鹅的免疫试验中,0.5m l组抗体水平上升过程缓慢,免疫后4周抗体水平才达4 log2以上,1与2 m l组在免疫1周后上升速度较快,免疫后2周即达4 log2以上,抗体水平相近,但2 m l免疫组免疫后5~7周抗体水平均低于1 m l免疫组。说明接种剂量为1或2 m lH 5N 1油苗比接种0.5 m l的免疫效果好,尤以1 m l免疫剂量效果最好。雏鹅在7、14日龄或14、21日龄作2次免疫和7、14、21日龄作3次免疫,首免后抗体上升速度快,各检测点抗体水平均值相近,均在首免后3周达到4 log2以上,4~5周达6 log2以上,4~7周的抗体水平均高于14日龄1次免疫组,且提前2周达到4 log2以上,说明2次、3次免疫组的抗体水平高于1次免疫组,而2次与3次免疫组的抗体水平无明显差异。以上结果说明,在肉鹅生产的禽流感免疫中,选择以14日龄首免0.5 m l/只,21日龄2免接种1 m l/只可取得较为理想的免疫效果。  相似文献   
82.
建立了一种用反相高效液相色谱测定啶菌噁唑的定量分析方法。采用C18ODS色谱柱,以甲醇-水(75∶25,体积比)作为流动相,流速1.0mL/m in,检测波长220nm。啶菌噁唑色谱图显示两个吸收峰,分别为两个同分异构体Z体和E体。在400700μg/mL浓度范围内,标准溶液浓度和吸收峰面积之间有良好的线性关系,回归方程为Y=4.846 7x+232.85,相关系数r为0.999 2;对原药溶液及其制剂溶液测定的重复性SR分别为0.004 0和0.004 7。该方法准确、精密,适用于啶菌噁唑的定量分析。  相似文献   
83.
84.
The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients.  相似文献   
85.
建立同时测定4种氟喹诺酮类抗菌物(左氧氟沙星、培氟沙星、沙拉沙星和洛美沙星)的高效毛细管电泳(HPCE)法。考察了缓冲液离子浓度和pH、分离电压、运行温度等电泳参数,确立了最佳的电泳条件:缓冲液为10 mmol/L磷酸二氢钾-20 mmol/L硼砂(pH9.0,内含35mmol/L SDS),紫外检测波长278 nm,分离电压28 kV,运行温度25℃。结果表明,4种药物在8min内得到完全分离,分离度R为1.2以上。方法精密度(RSD)为0.22%~0.26%(迁移时间)和1.36%~2.39%(峰面积),回收率99.60%以上。该法快速、简便、准确。  相似文献   
86.
微量元素硒对成年皖西白鹅输卵管膨大部粘蛋白的影响   总被引:1,自引:4,他引:1  
应用组织化学PA S-AB染色和定量图像分析法,研究了不同水平微量元素硒对成年皖西白鹅输卵管膨大部粘蛋白的影响,结果表明:日粮中添加0.2 m g/kg微量元素硒鹅输卵管膨大部粘蛋白与对照组(不加硒)差异显著(P<0.05);日粮中添加0.60 m g/kg与对照组差异极显著(P<0.01);当日粮中添加硒到1.1 m g/kg时,与对照组差异不显著(P>0.05);说明随着硒添加量的加大,皖西白鹅会发生慢性中毒。因此,微量元素硒对成年皖西白鹅输卵管膨大部粘蛋白的影响有显著差异。  相似文献   
87.
4味中药及其与抗菌药的复方制剂的MIC测定   总被引:3,自引:0,他引:3  
用改进的试管两倍稀释法测定了黄连、鱼腥草、大青叶和苦参4味中药及其相互配伍(1:1)对标准大肠杆菌的最小抑菌浓度和4味中药与抗菌药配伍(1000:1)对临床分离鸡大肠杆菌的最小抑菌浓度。结果表明,4味中药及其相互配伍对大肠杆菌标准株有一定的抑制作用,其MIC值介于3.91—62.50mg/mL之间,其中大青叶和鱼腥草以1:l配伍对大肠杆菌抑菌效果最好,MIC为3.91mg/mL;对临床分离株,单方药中黄连抑菌效果最好,MIC为31.25mg/mL,24种复方药中,黄连和盐酸多西环素或加替沙星以1000:1配伍的抑菌效果最好,其MIC为3.91mg/mL。  相似文献   
88.
Unidentified heats contribute to declining fertility rates in English dairy herds. Several techniques have been advocated to improve heat detection rates. Despite demonstrable technical efficacy and cost-effectiveness, uptake is low. A study in South West England used the Theory of Reasoned Action (TORA) to explore dairy farmers' attitudes and beliefs towards heat detection techniques. Few farmers were convinced that following prescribed observation times, milk progesterone testing and using pedometers would fit their system or improve on their current heat detection practices. Perceived difficulty of using a technique was not a constraint on adoption. Without promotion that addresses identified barriers and drivers to adoption, little change in current practice can be expected.  相似文献   
89.
This study was performed to evaluate the effect of beta-tricalcium phosphate and poly L-lactide-co-glycolide-co-epsilon-caprolactone (TCP/PLGC) membrane in the repair of partial bone defects in canine proximal humerus. Three adult mixed-breed dogs were used during the experimental period. The length of the defect was quarter of the full length of humerus, and width of the defect was quarter of middle diameter of the lateral aspect of humerus. The humeri of each dog were divided into treatment (TCP/PLGC) and control groups. The defect was covered with TCP/PLGC membrane in treatment group. To evaluate regeneration of the bone, computerized tomography (CT) and histopathologic examination were performed. The radiopaque lines were appeared at the original defect sites in TCP/PLGC group but below the original site in control at 4th week. Radiopacity and thickness of the defect sites, and radiopaque lines were more increased at 8th week than those of 4th week. Histopathologic findings revealed fibrous connective tissue migration into the defect and the migration inhibited the structure of new cortex to be placed in the original level in control whereas new cortex growth was found in the level of original line in TCP/PLGC group. However, the new cortical bone in the TCP/PLGC group was thinner and less organized than the adjacent intact cortex, and the amount of new cancellous bones were also scanty. The result suggested that TCP/PLGC membrane is a good guided bone regeneration material to restore the original morphology of humerus in partial defect.  相似文献   
90.
Three dead dogs were brought to the College of Veterinary Medicine, Kyungpook National University for study. Clinically, all the dogs showed emaciation, anorexia, depression, hemorrhagic vomiting and diarrhea for 7~10 days before death. All the clinical signs were first noted for about one month after feeding the dogs with commercial diets. At necropsy, all 3 dogs had severe renal damage with the same green-yellowish colored nephroliths in the renal pelvis. They also showed systemic hemorrhage and calcification of several organs, which might have been induced by uremia. Microscopically, necrosis, calcification and calculi were detected in the renal tubules, and especially in the proximal convoluted tubules and collecting ducts of the kidney. These findings were supportive of a mycotoxic effect, and especially on their kidneys. However, the precise cause of the toxic effect in these cases of canine renal failure could not be determined.  相似文献   
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