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51.
Methodological aspects of flow-cytometric evaluation of the phagocytic properties of equine neutrophils were elucidated. The kinetics of attachment and ingestion were studied, and the phagocytic process was more rapidly completed when serum-opsonized yeast cells were used than with use of IgG-opsonized yeast cells. Trypan blue was successfully used to quench fluorescence of non-ingested yeast cells. There were only minor differences in the kinetics of phagocytosis between quenched and un-quenched samples, indicating that attachment is rapidly followed by ingestion. Trypan blue quenching caused loss of cells with light scattering properties of granulocytes, although this did not affect the determined frequencies of truly phagocytic neutrophils. Aggregation of yeast cells proved to be a disturbance but not an obstacle to the determination of frequencies of actively phagocytic cells. Flow cytometry is well suited for studies of phagocytosis of yeast cells by equine neutrophils, and the trypan blue quenching provides a means of eliminating false-positive events due to aggregation of yeast cells. The main advantage of the flow-cytometric method is the possibility of rapid processing of a large number of samples, making the method useful for studies of herds.  相似文献   
52.
Two groups of blue fox pups about 1½— 2 and 2½—3 months old, respectively, suffering from experimental encephalitozoonosis, were examined clinically and serologically. Antibodies to Encephalitozoon cuniouli were detected in all pups, the titres varying within the range 10–12,800. In addition to unspecific signs of disease the pups showed various neurological disturbances including ataxia, posterior weakness, lameness and circling behaviour, terminaiting in recumbency, paralysis or convulsions. Reduced sight or blindness was observed occasionally. Some of the pups appeared thirsty. Haematological examinations revealed pronounced leukocytosis without any conspicuous shift within the various groups of leukocytes. Biochemical examinations of serum showed significant elevated values of urea nitrogen, creatinine, and magnesium concentrations, reflecting renal dysfunction. Alanine aminotransferase was found significantly depressed in both groups. Raised levels of total protein were demonstrated due to pronounced hyperglobulinaemia. This finding, together with the common occurrence of generalized polyarteritis nodosa and proliferations of plasma cells in clinically affected pups, is probably a result of autoimmune disturbances initiated directly or indirectly by the protozoan infection.  相似文献   
53.
A reduction in the number of wounds of pears and apples which developed blue mould (Penicillium expansum) infection was associated with reduced spore concentration. An experimental ultraviolet irradiation treatment of water in a fruit-handling system reduced both spore numbers and fruit rots, but not to a level which would suggest that the technique is worth pursuing to a commercial application stage.  相似文献   
54.
The present experiments were performed to study the effects of a single high intravenous dose of Liquoid (10 mg/kg body weight) upon platelets, coagulation activities and hematocrit in blue foxes, and their correlation with the survival time. Both “short-living” (< 9 h) and “long-living” (24 h or more) blue foxes showed a marked consumption of coagulation factors, initial fall in fibrinogen, positive ethanol gel test and a gradual decrease in platelet counts. In addition “short-living” animals developed a marked rise in hematocrit, reflecting a considerable increase in vascular permeability. We conclude that activation of plasma proteases has as one of its effects increased permeability in microvasculatory vessels and that this may play a central role for the course and outcome of Liquoid-induced disseminated intravascular coagulation.  相似文献   
55.
安徽省蓝舌病流行病学调查   总被引:2,自引:0,他引:2  
1987~1991年,安徽省的三个县发生了绵羊的蓝舌病,并经病毒分离、鉴定证实。绵羊的发病率为33.0%,病死率11.3%。对反刍家畜的血清学调直显示,疫区中的阳性率高于非疫区。黄牛、水牛、绵羊的阳性率无统计学差异,均明显高于山羊及乳牛;美利奴绵羊的阳性率高于考力代及罗姆尼;放牧羊群的阳性率高于舍饲;无明显的年龄差异。调查得本省库蠓12种,尖喙库蠓、原野库蠓及日本库蠓为本省嗜畜的优势种。分析认为:原野库蠓是最可疑的媒介昆虫,水牛、黄牛是本省蓝舌病病毒越冬的保毒宿主。  相似文献   
56.
The serum proteins in 1 group of healthy breeders, 1 group of healthy pups and 4 groups of foxes suffering from various diseases were separated electrophoretically on cellulose acetate membranes. In most of the sera, the proteins were separated into 1 albumin fraction and 5 globulin fractions designated alpha1, alpha2, alpha3, beta and gamma. The mean concentrations of the total proteins and the various serum fractions in the disease groups were compared statistically with the mean values of the normal groups.A nosematosis group was characterized by a distinct hypergammaglobulinaemia together with an increase in the total protein — and a decrease in the albumin concentrations. However, in 2 cubs recovering from nosematosis the hypergammaglobulinaemia was shown to be reversible.In a feed intoxication group the concentration of albumin was found to be lower and the alpha3-globulin higher than the corresponding values in the healthy group. A virus hepatitis group was characterized by a decrease in the concentrations of albumin and beta-globulin and an increase in the alpha1- and alpha3-globulins. In the toxoplasmosis group the total protein and alpha1- and alpha3-globulins showed concentrations below the normal values.  相似文献   
57.
用二步法生产天然食用栀子蓝色素   总被引:15,自引:0,他引:15  
采用微生物发酵和酶促反应分开的方法(二步法)制得色泽鲜明的栀子蓝色素。结果表明,栀子果粉中与京尼平甙共存的α-藏花素是影响色素色泽的主要因素之一。用一种大网孔树脂栀子水浸液过柱吸附,可将京尼平甙与藏花素分离。氨基酸种类对二步法形成色素的色泽影响甚大。其中亮氨酸,精氨酸和苯丙氨酸所形成色素的色泽最佳,呈美丽蓝色。  相似文献   
58.
为探究柚子皮对染料废水的吸附规律及最佳条件,以亚甲基蓝模拟废水,进行了柚皮粉对亚甲基蓝的吸附规律及吸附效果试验。结果表明:在温度30℃,pH 8,震荡时间60min的条件下,0.4g柚皮粉可使100mL浓度为140mg/L亚甲基蓝的去除率达83%以上,30℃下柚子皮理论饱和吸附量为133mg/g。柚子皮吸附亚甲基蓝的过程以物理吸附为主,包括外部液膜扩散、表面吸附和颗粒内部扩散等过程,可以用Langmuir、Temkin等温吸附方程和二级吸附速率方程进行很好的描述。  相似文献   
59.
60.
以柞蚕5龄幼虫为材料添食柞蚕微孢子虫(Nosema pernyi,Np),通过测定与分析不同性别5龄幼虫血淋巴蛋白质含量和组成变化的差异,为探究柞蚕对柞蚕微孢子虫感染的免疫应答提供依据。感染柞蚕微孢子虫的不同性别柞蚕5龄幼虫的血淋巴蛋白质含量随蚕体发育进程出现不同的变化:雌性个体与雄性个体分别在添食Np后24 h与48 h,血淋巴蛋白质含量极显著增加(P<0.01),且持续至添食后96 h,其中雌性个体的血淋巴蛋白质含量又极显著高于雄性个体(P<0.01);在添食Np后120 h,雌、雄个体的血淋巴蛋白质含量与对照组无显著性差异(P>0.05)。SDS-PAGE分析表明,添食Np后的柞蚕5龄幼虫血淋巴蛋白质组成与对照组基本一致,均显示出20条分子质量在20.1~97.2 kD的蛋白条带,其中雌、雄个体在添食后96 h,大小约44 kD的蛋白条带明显加深,大小约28 kD的蛋白条带雌性个体在添食后144 h、雄性个体在添食后120 h明显加深,且雄性个体在添食后120~168 h大小约42 kD的蛋白条带明显加深,但在添食后192 h与对照组无明显差异。研究结果说明Np侵染后,柞蚕5龄幼虫血淋巴蛋白质的含量及组成均产生了一定的变化,并且雌雄个体间的变化存在差异。  相似文献   
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