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81.
Additional immunization trials were performed to study the immunogenicity of the purified skin antigen of Marek's disease virus which was inoculated, together with Freud's complete adjuvant, into one-day-old chicks. As compared to non-vaccinated chickens and also to chickens vaccinated by herpesvirus turkey (which reduced the mortality by 45.54%) the purified skin antigen reduced the mortality by 69.50%.

In the case of immunization with protein extract from the lymphoblastoid cell line of Marek's disease lymphomes mixed with natural dsRNA showed 38.99% reduction of mortality. DEAE-dextran which had exerted an adjuvant effect in our previous report did not by itself reduce mortality caused by Marek's disease.

Groups of chickens vaccinated with the turkey herpesvirus with protein extract mixed with dsRNA, and a group of chickens inoculated with 0.04 g.ml−1 DEAE-dextran, had a higher whole complement activity in pooled serum from 107 days after challenge than chickens free of Marek's disease.  相似文献   

82.
Hemolytic assays were used to compare alternate and classical C pathway activities in sera obtained from clinically normal newborn dairy calves and their mothers at the time of delivery. Mean alternate and classical CH50 concentrations in sera from newborn calves were both significantly lower than in their dams (P less than 0.001). The titer of alternate C pathway activity, expressed as CH50 units/ml, in sera from 17 calves was 12.9 +/- 5.5, whereas for the cows it was 25.8 +/- 6.2. The ratio of cow: calf serum alternate CH50 titers averaged 2.25 +/- 0.80 and ranged from 0.88 to 4.14. Classical CH50 titers were 78.0 +/- 42.7 units/ml in calf sera and 246.0 +/- 44.5 in cow sera. The ratio of cow: calf serum classical CH50 titers averaged 3.71 +/- 1.49 and ranged from 1.19 to 6.87. The wide range of values, noted for both the alternate and classical C pathways, within maternal and neonatal groups was assumed to reflect the biologic variability of complement levels in bovine serum. The possible relationships between deficient levels of alternate and classical CH50 activity in newborn calves and their susceptibility to infections is discussed.  相似文献   
83.
Complement receptor type 3 (CR3)- and Fc receptor (FcR)-mediated metalloproteinase-9 (MMP-9) secretion and their intracellular signalling of bovine neutrophils were evaluated. Relative density of MMP-9 secreted by neutrophils stimulated with opsonized zymosan (OPZ, stimulant for CR3) was significantly (p < 0.05) increased when the OPZ concentration was increased from 0 to 0.4 mg/ml. Similar results were obtained for neutrophils stimulated with heat-aggregated IgG (Agg-IgG, stimulant for Fc receptor) at concentrations from 0 to 0.40 mg/ml. Preincubation of neutrophils with 1–30 nmol/L wortmannin (phosphoinositide 3-kinase inhibitor) resulted in inhibition of MMP-9 secretion induced by stimulation with OPZ and Agg-IgG in a concentration-dependent manner, 30 nmol/L wortmannin causing complete inhibition. Similarly, preincubation of neutrophils with 0–100 μmol/L genistein (tyrosine kinase inhibitor) also resulted in inhibition of OPZ- and Agg-IgG-induced MMP-9 secretion in a concentration-dependent manner, with 100 μmol/L genistein causing complete inhibition. Significant (p < 0.05) positive correlations were found between MMP-9 and luminal-dependent chemiluminescent response (LDCL) in the case of stimulation with OPZ (r = 0.754) and in the case of stimulation with Agg-IgG (r = 0.728). Our findings suggested that CR3 and FcR play a critical role in production of MMP-9 and may be regulated by intracellular signal transduction, including that by phosphoinositide 3-kinase (PI3K) and tyrosine kinase (TK).  相似文献   
84.
Optimal conditions for assaying hemolytic complement of goat (caprine) and swine (porcine) sera were determined. Effects of the following were tested: pH, ionic strength, calcium and magnesium ion concentrations, time and temperature of incubation, and ethylenediamine tetracetate concentration. Guinea pig erythrocytes sensitized with goat or cattle antibodies were the most sensitive target cells for goat complement. Sheep and cattle erythrocytes sensitized with rabbit hemolysin were the best target cells for swine complement. Barbital buffer, pH 7.3, ionic strength of 90 nmM relative salt concentration, containing 0.5 mM CaCl2 and 1 mM MgCl2 was the best for swine complement assay. Goat complement lysed best in a barbital buffer, pH 8, ionic strength of 90 to 120 mM of relative salt concentration, in presence of 0.5 mM CaCl2 and 1 mM MgCl2. The optimal incubation temperature was 37 degrees C for both complements. The complement dependent lysis required 75 minutes to reach its maximum. Ethylenediamine tetracetate in 4 mM concentration completely inhibited lysis by both species complements. The CH50 for goat sera varied between 18 and 75 per ml, in swine sera between 75 and 210 per ml.  相似文献   
85.
中草药添加剂对生长肥育猪免疫功能的影响研究   总被引:18,自引:0,他引:18  
 选用20 kg左右的“杜长大”三元杂交猪120头,分成对照组、中药组、中药+西药组,每组4个重复,进行饲养试验。每期实验结束前,每组采集8头猪血样,测定生长育肥猪血清中免疫球蛋白IgG,IgA,IgM和补体C3,C4的含量。结果表明:在20~30 kg,30~70 kg和70~110 kg阶段,与对照组相比,中药组、中+西组猪的血清IgG水平,分别提高了23.75%(P<0.05)和18.49%(P<0.05),17.66%(P<0.05)和13.93%(P<0.05),14.79%(P<0.05)和11.87%(P<0.05);IgM水平,分别提高了25.04%(P<0.05)和14.99%(P<0.05),22.81%(P<0.05)和15.18%(P<0.05),5.79%(P>0.05)和4.23%(P>0.05);IgA水平,分别提高了9.71%(P>0.05)和0.57%(P>0.05),16.92%(P<0.05)和7.60%(P>0.05),15.01%(P<0.05)和7.23%(P>0.05); C3水平,分别提高了12.16%(P<0.05)和14.19%(P<0.05),15.87%(P<0.05)和17.46%(P<0.05),14.29%(P<0.05)和21.43%(P<0.05);C4水平,分别提高了13.51%(P<0.05),5.02%(P<0.05),6.67%(P<0.05).研究结果提示,中草药添加剂对生长育肥猪体液免疫功能的影响,不仅促进免疫球蛋白的生成,而且还促进补体的生成,从而改善机体的体液免疫功能。  相似文献   
86.
从图书馆的教育功能和服务职能看纸质文献和数字文献的优势互补。  相似文献   
87.
从介绍多媒体技术入手,阐述在教学中应用多媒体技术带来的效应,总结了当前在教学中应用多媒体技术尚存在的不足之处。进而提出进一步发挥多媒体技术在教学中的作用的对策建议,突出主张多媒体教学和传统教学的共处、结合和竞争,倡导在竞争和互补中推动多媒体教学的发展。  相似文献   
88.
 本文报道了分布于我国云南中部的中国雉鸡(Phasianus colchicus)的染色体组型、G-带及高分辨G-带带型。染色体数目2n=82。性染色体雄性为ZZ、雌性为ZW。40对常染色体中,1号为近中着丝粒染色体,5号为近端着丝粒染色体,其余皆为端部着丝粒染色体;性染色体Z为中着丝粒染色体,W为近端着丝粒染色体。全部染色体进行测量分析,计算相对长度和双臂染色体着丝粒指数。根据相对长度和着丝粒指数,绘制了染色体组模式图。制作了1—20号常染色体和性染色体Z的中期G-带以及全部染色体的高分辨G-带,并进行了两种G-带带型特征的描述和比较,绘制了两种G-带比较模式图。  相似文献   
89.
90.
Control of mycobacterial infection constitutes a priority for human and animal health worldwide. However, effective vaccines are needed for the control of human and animal tuberculosis (TB). Adult zebrafish have become a useful model for studying the pathophysiology of mycobacterial infection and for the development of novel interventions for TB control and prevention. Recently, parenteral and oral immunization with the heat‐inactivated Mycobacterium bovis vaccine (M. bovis IV) protected wild boar against TB. The objectives of this study were to provide additional support for the role of M. bovis IV in TB control using the zebrafish model and to conduct the first trial with this vaccine for the control of fish mycobacteriosis. The results showed that M. bovis IV protected zebrafish against mycobacteriosis caused by low and high infection doses of Mycobacterium marinum and provided evidence suggesting that the protective mechanism elicited by M. bovis IV in zebrafish as in other species is based on the activation of the innate immune response through the C3 pathway, with a role for the regulatory protein Akr2 in this process. These results encourage the use of M. bovis IV for TB control in different species.  相似文献   
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