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941.
942.
943.
细粒棘球蚴细胞系(13G-5)细胞代谢抗原的免疫原性和反应原性 总被引:2,自引:0,他引:2
应用培育成功的人源细粒棘球蚴细胞系(13G-5)细胞的天然代谢抗原,接种昆明小鼠,于接种后第14天给免疫小鼠接种人源细粒棘球蚴原头节约1 000 个,于200 d 剖检观察有无包囊形成,病理切片鉴定;并用该抗原作为诊断抗原,使用间接血凝(IHA)、琼脂扩散(AGD)试验,检测临床确诊的细粒棘球蚴病人血清。以多房棘球蚴病人血清、细颈囊尾蚴羊血清及正常人血清作为对照。结果表明,该抗原能使60% 的小鼠获得完全抵抗细粒棘球蚴原头节攻击的能力,未完全获得保护的小鼠形成包囊的数量、大小较对照组明显减少,且为不育囊;使用该抗原IHA 检测31 份血清,阳性24 份,阳性率77.42% ,AGD检测30 份血清,阳性13 份,阳性率43.33% ,2 种方法对多房棘球蚴病人血清和细颈囊尾蚴羊血清及正常人血清不起反应。 相似文献
944.
An intensive vertically integrated monitoring program for broiler breeders and their offspring was set up in a Belgian poultry integration between 1993 and 1997. Serology for anti-reovirus antibodies was performed by enzyme-linked immunosorbent assay on blood samples taken from the broiler parents throughout rearing and production and also on blood samples taken at day-old and at slaughter from the broilers. Furthermore, production parameters of the birds were registered. All data were used two by two in a simple correlation study to calculate the degree to which these variables were linearly correlated. The reovirus antibody pattern indicated frequent field infections breaking through vaccinal immunity in the broiler parents. Under the epidemiologic conditions of this study, high antibody titers in the parents or in the broilers at day-old were significantly correlated with poor feed conversion, increased mortality, increased slaughterhouse condemnation, and low production score in the broilers. These correlations strongly support the view that reovirus infections can be economically important under European conditions of broiler production. Improvement of reovirus vaccines or the vaccination scheme in broiler parents or both may lead to better production results in the broiler offspring. 相似文献
945.
梅花鹿幼鹿人工培育技术的研究 总被引:3,自引:0,他引:3
本试验首先通过幼鹿日粮调配寻求最佳合理的日粮配合,首次制定出了幼鹿发育阶段精料年供量曲线。通过对幼鹿采用直线培育措施,加强饲养管理,取得了显著的效果。其中日增重提高35 % ,初角茸产量提高了3 倍,头锯茸产量提高了77-9 % ,创造了历史最高产,幼公鹿出生5 个月开始产茸,幼母鹿培育至17 个月即可参加配种,配种准胎率100 % ,仔鹿成活率达到92 % 。 相似文献
946.
947.
948.
Antigenicity of cortical bone allografts in dogs and effect of ethylene oxide-sterilization. 总被引:7,自引:0,他引:7
M Tshamala E Cox H De Cock B M Goddeeris D Mattheeuws 《Veterinary immunology and immunopathology》1999,69(1):47-59
The aims of the present study were to determine the antigenicity of cortical bone allografts and the effect of ethylene oxide-sterilization (EO-sterilization). Cortical bone allografts from one donor dog were implanted in a muscle pouch in four groups of four dogs each. The grafts were either fresh, EO-sterilized, demineralized or demineralized and EO-sterilized. The immune response against the grafts was determined by measuring the antibody response against surface antigens of donor cells and by the mixed lymphocyte reaction. Dogs receiving EO-sterilized grafts or bone matrix did not demonstrate an immune response. Only two of the four dogs with fresh cortical bone grafts showed a very weak immune response. This suggests a priming of the host by the fresh bone grafts. However, implanting skin grafts from the donor dog subdermally, in one dog of each of the groups, four months after implanting the bone grafts did not induce a secondary immune response. Macroscopic and histologic examination of the bone grafts five months after their implantation consistently revealed graft resorption (activity of osteoclasts) and vascularization of the fresh bone grafts, but not of EO-sterilized fresh grafts. For most EO-sterilized grafts, a strong inflammatory reaction was present in the tissues surrounding the graft and this was not apparent around the non-sterilized grafts. The absence of resorption and the presence of the inflammation seemed to be unwanted effects of the EO-sterilization. The EO-sterilisation did not affect osteoinduction since osteocytes were observed in the EO-sterilized demineralized grafts. Results indicate that cortical bone allografts used in the present study are very weak antigens and that the EO-sterilization procedure used has no effect on osteoinduction, but decreases bone resorption. 相似文献
949.
950.
通过物料的受力分析确定了物料攫取条件,并分析了物料层厚度h0 与攫取角β、模辊径比λ之间的关系,从理论上解释了颗粒机生产率随模辊径比λ和攫取角β、压辊数目Z变化的规律,从而简化部件的研制过程,为正确设计颗粒机提供了科学根据 相似文献