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191.
本试验对马传贫血清抗体酶联免疫吸附试验(ELISA)的耐热性进行了比较研究.对2匹弱毒疫苗免疫马跟踪检测17个月,在接种3周后ELISA检测均呈阳性,其中一匹马ELISA抗体阳性持续到接种后10个月,另一匹马ELISA抗体阳性可持续到接种后一年.对两匹马的所有不同时期采集的血清样品经75℃加热5 min处理后,用ELISA检测均为阴性.另选6匹马传贫弱毒疫苗免疫马血清且ELISA检测抗体呈阳性的30个样品,经75℃加热5min处理后,均由阳性转变成阴性.4匹经马传贫病毒辽毒株(LN-EIAV)实验感染马且ELISA检测抗体呈阳性的血清样品,经75℃加热5 min处理后,结果仍为阳性.23匹ELISA检测抗体呈阳性的自然感染马血清样品,经加热处理后,19匹马血清样品仍为阳性,4匹马血清样品由阳性转变成阴性.结果表明弱毒疫苗免疫马较自然感染马血清抗体耐热性稍差.  相似文献   
192.
Infectious salmon anemia virus (ISAV) infection is a constant major threat to farmed and wild Atlantic salmon worldwide. Many epidemics have recently been reported in the most important salmon farming regions of the world, including Chile (2007–2009), where ISAV generated the most important disease and economic crisis in history of the salmon industry of the country. The spread of ISAV within a region is most likely by local or neighborhood spread from an infected farm; however, there is evidence that anthropogenic activities, such as movement of live or harvested fish or their byproduct, may have played a more important role than environmental or passive transmission in the 2007–2009 outbreak. Atlantic salmon farms (n = 421) were retrospectively followed from stocking to harvesting in southern Chile at the time of the ISAV epidemic (2007–2009). The effect of husbandry and spatial risk factors, in addition to contact-network risk factors, which were obtained from the social network analyses, on time to first ISAV infection was estimated using a multivariable Cox proportional hazards model. Five variables were retained in the final fitted model: co-existing multiple generations on a farm (hazard ratio [HR] = 2.585), mean smolt weight at stocking greater than 120 g (HR = 1.165), farm area (per km2) (HR = 1.005), and increased number of shipments entering a farm, i.e. the farm input degree (HR = 1.876) were associated with reduced time to infection; whereas time-to-infection was longer for farms located farther from an ongoing ISAV outbreak (HR = 0.943). It was demonstrated that movements of latently infected fish resulted in approximately 7 outbreaks, and potentially explain about 6% of the total number of cases during the epidemic. Results from this study provide new information about the mechanisms of spread of ISAV in one the largest documented ISAV epidemics in the world. Findings may be used to support the design and implementation of risk-based surveillance and control programs that may help to prevent, detect and control future ISAV outbreaks.  相似文献   
193.
CAV与REV共感染SPF鸡对疫苗免疫反应的抑制作用   总被引:3,自引:0,他引:3  
用1日龄SPF鸡人工感染鸡贫血病毒(CAV)和禽网状内皮增生病病毒(REV),探讨病毒感染对鸡体疫苗免疫反应的影响。结果表明,在用禽流感病毒(AIV,H5和H9)疫苗免疫后,CAV与REV单独感染均显著抑制了鸡体对H5和H9亚型禽流感病毒灭活疫苗的HI抗体反应,在CAV与REV共感染后,这种抑制作用更为明显。CAV单独感染后鸡体对新城疫病毒(NDV)和传染性法氏囊病病毒(IBDV)疫苗的免疫反应受到抑制,但与对照组在统计学上的差异不显著,然而,CAV可以显著加重REV感染对鸡体在NDV和IBDV疫苗免疫后抗体反应的抑制作用。从而证实CAV与REV共感染在疫苗免疫抑制上有协同作用。  相似文献   
194.
应用微波间接酶标抗体染色法(WIEAS)对鸡贫血病毒(CAV)感染雏鸡Lasota疫苗免疫后免疫器官组织的CD4^ 、CD8^ T细胞数量及CD4^-与CD8^ T细胞比值的变化进行了动态研究,结果发现,CAV感染1日龄雏鸡Lasota疫苗免疫后,其胸腺、脾脏和盲肠扁桃体的CD4^ 、CD8^ T细胞数量及CD4^ 与CD8^ T细胞比值均程度不同地低于CAV未感染Lasota疫苗免疫对照雏鸡。表明,CAV感染雏鸡免疫器官组织对Lasota疫苗的细胞免疫应答机能降低或减弱。  相似文献   
195.
196.
拟制备针对鸡传染性贫血病毒(CIAV) VP2蛋白的单克隆抗体(mAb),为CIAV的诊断和病毒生物学特性研究提供有用制剂.以PCR技术扩增CIAV VP2基因并克隆到原核表达载体pET-32a中,经IPTG诱导表达.以原核表达的融合蛋白免疫BALB/c小鼠,利用杂交瘤技术研制并筛选分泌抗CIAV VP2蛋白mAb的阳...  相似文献   
197.
采用四种补铁制剂于仔省3日龄时分别一次肌肉注射,测定血红点白含量、增重等指标,研究山梨醇铁及其它类似制剂对预防仔猪贫血及促进生长的影响。试验结果表明:①各用药组仔猪各项指标均高于对照组;②福铁维组和100mg Fe/ml山梨醇铁组仔猪的血红蛋白含量升高及增重都极显著地高于对照组(P<0.01),期末增重比值分别达到135.04%与119.02%;③100mg Fe/ml山梨醇铁注射液吸收良好,无毒副作用,对预防仔猪缺铁性贫血及促进生长有较明显的效果,优于国内同类产品。  相似文献   
198.
AIM: To observe the effects of total saponins of Panax ginseng (TSPG) on the promotion of hematopoiesis and to explore the underlying mechanism in treating aplastic anemia (AA) in a mouse model.METHODS: For preparation of AA model, BALB/c mice were exposed to sublethal dose of 5.0 Gy γ radiation, followed by transplantation of lymphocytes from DBA/2 donor mice. The experiment was divided into 6 groups, including normal control group, AA model group, TSPG treatment groups with low, medium and high doses, and positive control group with cyclosporine A (CsA). Both TSPG and CsA were administered by gastrogavage. After 15 d treatment, the peripheral hemogram was tested, the cytokine contents in serum were measured, and bone marrow semisolid culture of colony-forming assay was conducted for determining hematopoietic progenitor cells. The protein levels of extracellular signal-regulated kinase 1/2 (ERK1/2) and its phosphorylation status in the bone marrow cells were determined.RESULTS: Curative effect of TSPG in treating AA mice was satisfactory. Peripheral counts of white blood cells and platelet, and concentration of hemoglobin in TSPG groups with medium and high doses were significantly higher than those in model control. TSPG increased the colony numbers of CFU-E, BFU-E, CFU-GM and CFU-MK derived from hematopoietic progenitor cells. Meanwhile, up-regulation of the phosphorylated ERK1/2, decreased contents of Th1 cytokines and increased contents of Th2 cytokines in the serum were observed.CONCLUSION: TSPG possess the dual efficacies on the promotion of hematopoiesis and immunoregulation in AA mice by regulating the expression of Th1/Th2/Th17 cytokines and increasing the phosphorylation of ERK1/2.  相似文献   
199.
To evaluate the dietary protein utilization and iron deficiency anemia as affected by the faba bean nutrient intake, a bioassay with rats was carried out with different experimental diets containing four faba bean products (stewed beans ‘Medammis’, deep fried dough ‘Falafel’, boiled germinated beans ‘Nabet Soup’ and poured paste ‘Bissara’) widely consumed in the Middle East. Amino acid composition of all faba bean products was determined and compared to raw beans. Severe heat-processing markedly decreased some essential amino acids, especially phenylalanine, cystine, methionine and tryptophan. Protein scores were 24.6, 19.5, 29.2, 28.2 and 35.6 for raw faba beans, ‘Medammis’, ‘Falafel’, ‘Nabet Soup’ and ‘Bissara’, respectively. ‘Bissara’ possessed the highest nutritional value, since it had the lowest GDR value [Grams consumed of product to cover the daily requirements for adult man in protein (63 g) and in energy (2900 kcal)] for the limiting amino acids (L A A). As indicated by P S/150 values [Satisfaction of the daily requirements of the adult man when 150 g (one can content) are consumed of product] for L A A, i.e. methionine+cystine (lowest P S/150 value), the above-mentioned faba bean products cover about 53, 77, 77 and 97% of the daily requirements of adult man in L A A, respectively. Fecal nitrogen excretion increased and true nitrogen digestibility decreased significantly (p<0.01) with the inclusion of ‘Medammis’ in the diet. ‘Nabet Soup’ exhibited the highest true nitrogen digestibility. In contrast, the biological value of nitrogen was apparently unaffected. Highest blood hemoglobin level was found in rats fed diets containing ‘Bissara’, ‘Falafel’ and ‘Nabet Soup’, whereas the addition of ‘Medammis’ in the diet induced a significant (p<0.05) reduction in blood hemoglobin level of fed rats.  相似文献   
200.
根据鸡贫血病毒Cux_1株基因组序列设计了一对引物,通过PCR扩增出VP1基因。将扩增出的片段克隆到pGM_T载体上,通过测序分析证实该片段与鸡贫血病毒Cux_1株的VP1基因序列一致。然后将克隆化VP1基因亚克隆到PET_32a( )载体上并进行原核表达。SDS_PAGE和Western Blot分析表明,一个分子质量为70.4 kDa的重组蛋白获得了成功表达,并且鸡贫血病毒阳性血清能和重组蛋白发生反应。  相似文献   
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