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61.
Humoral and mucosal (secretory antibody)immune response to FMDV type Asia 1 in cattle was analyzed after vaccination and infection using virus neutralizing test (VNT). Vaccination (1/16th the usual dose) failed to protect cattle from generalized clinical disease following experimental FMDV Asia 1 infection. Our results showed that infection induced higher and prolonged serum antibody titres indicating antigen mass is important for optimal immune response. Experimental FMDV infection induced significant secretory antibody (mucosal) response in cattle. Though, there was no difference in the serum antibody response between the cattle that developed generalized infection (unprotected) and those with only localized infection (protected), secretory antibody response differed, wherein the unprotected cattle had higher secretory response than protected cattle. Thus, FMDV Asia 1 infection stimulates a similar serum antibody response and a unique secretory antibody response among the infected cattle. An erratum to this article can be found at  相似文献   
62.
A study was conducted to determine the effect of blood sample mishandling on the performance of an enzyme-linked immunosorbent assay for the detection of antibodies against Erysipelothrix rhusiopathiae. Eleven sample maltreatments (storage at −10 °C, storage at 4 °C, heat treatment of clotted blood, haemolysis, repetitive freeze–thaw cycling, and substitution of plasma in place of serum) were simulated in a laboratory environment and then run concurrently against a gold standard sample (storage at −80 °C).The mishandling treatment groups that simulated high levels of haemolysis had significantly lower optical density (OD) readings when compared to the gold standard. However, the magnitude of the effects was relatively small and only samples with OD values close to the cut-off changed state from positive to negative. Heat treatment had a minor, but non-significant, effect on OD values. Findings from this study suggested that immunoglobulin G antibody was stable in the face of most common sample mishandling events.  相似文献   
63.
[目的]监测聊城周边地区猪圆环病毒病的感染和流行情况。[方法]以山东省聊城周边地区的7个养猪场的222份血清为材料,应用ELISA方法配合流行病学调查,检测猪圆环病毒抗体水平。[结果]检测发现7个养猪场的猪群都感染过猪圆环病毒,抗体阳性率在33.3%~83.3%。发病猪群都为5~10周龄的保育仔猪。猪群在断奶后1周左右,出现进行性消瘦,生长迟缓,采食量下降,被毛粗乱,精神差。剖检病变主要表现为发病猪和死亡猪全身淋巴结水肿,发黄,肾脏水肿,肺脏肿大,质地变硬。该疾病初步定为由PCV-2感染所致的猪断奶后多系统衰竭综合征(PMWS)。[结论]该研究为制定猪圆环病毒病的综合防制措施奠定了基础。  相似文献   
64.
[目的]探讨黑眶蟾蜍皮肤白蛋白的纯化及胰蛋白酶抑制活性。[方法]通过离子交换层析和凝胶过滤层析,从黑眶蟾蜍皮肤中得到其白蛋白,命名为BufomA-skin。65nmol/L的BufomA-skin分别与30nmol/Ltrypsin在25℃不同保温时间(0.25—24h)下测定胰蛋白酶抑制活性,计算剩余酶活力。[结果]BufomA-skin为单链蛋白,分子量约为66.7kDa。但在非还原状态下,50~66kDa条带呈弥散样。该蛋白有抑制胰蛋白酶水解小肽底物的活性,但对其他丝氨酸蛋白酶如凝血酶、糜蛋白酶、弹性蛋白酶及枯草杆菌蛋白酶无抑制。BufomA-skin与胰蛋白酶保温24h后,胰蛋白酶活性无恢复。[结论]黑眶蟾蜍皮肤白蛋白具有稳定的胰蛋白酶抑制活性,在黑眶蟾蜍防御天敌捕食的过程中发挥重要作用.  相似文献   
65.
李晓剑  张留光  姚玲  黎宗强  谢丽萍  李春艳 《安徽农业科学》2011,39(23):14137-14138,14155
[目的]纯化培养食蟹猴支持细胞,并测定不同血清浓度对细胞增殖的影响。[方法]分离并纯化食蟹猴支持细胞后,分别以5%、10%、15%、20%4种不同血清浓度的培养基对食蟹猴支持细胞进行培养。利用MTT比色法判断支持细胞的增殖情况,从而确定最佳的血清培养浓度。[结果]5%血清浓度的培养基对细胞增殖能力的影响与10%血清浓度的培养基差异不显著,15%与20%的血清浓度的培养基对细胞增殖能力的影响差异不显著,5%、10%与15%、20%的血清浓度的培养基对细胞增殖能力的影响差异极显著。[结论]15%的血清浓度是支持细胞增殖的最佳比例。  相似文献   
66.
李芳琼  刘海峰  朱砺 《安徽农业科学》2011,39(15):9281-9283,9320
[目的]探讨罗格列酮和血清对猪前脂肪细胞诱导分化过程中PPARα和PPARγ基因表达的影响。[方法]利用胶原酶消化法分离了猪皮下前脂肪细胞,采用3种不同分化培养液对猪前脂肪细胞进行了诱导分化,借助油红O染色提取法比较了不同分化培养液对分化过程中细胞内脂肪含量变化的影响,并运用实时定量RT-PCR方法检测了不同分化培养液细胞分化过程中PPARα和PPARγ基因表达的变化趋势。[结果]细胞内脂肪聚积以含罗格列酮的MⅡ最快,不含罗格列酮的MⅠ最慢。罗格列酮可极显著上调PPARγ基因的表达(P〈0.01),而对PPARα基因的表达存在一定的抑制作用,但不显著。血清对PPARγ基因的表达有极显著的上调作用(P〈0.01),而对PPARα基因的表达有极显著下调作用(P〈0.01)。[结论]罗格列酮可极大地促进PPARγ基因的表达,继而增进细胞内脂肪沉积;血清中可能存在PPARγ基因的激活剂,同时存在PPARα基因的抑制因子。  相似文献   
67.
68.
This study aimed to evaluate effects of orally administered copper (Cu) to Chios sheep breed on serum levels of aspartate aminotransferase (AST), l-alanine aminotransferase (ALT), lactate deydrogenase (LDH) and alkaline phosphatase (ALP), in order to establish a practical and effective method in diagnosing the prehemolytic stage of chronic Cu poisoning. Eighteen ewes were allocated to three treatments of six ewes and fed a diet that contained 16.4 mg/day of Cu. Ewes in treatment Cu-0 received no additional Cu (control), while those in treatments Cu-60 and Cu-95 received 60 and 95 mg additional Cu/day, respectively, as an oral solution of copper sulfate. Therefore the ewes in treatment Cu-0, Cu-60 and Cu-95 consumed 16.4, 76.4 and 111.4 mg Cu/day, respectively. Serum enzyme levels were similar among treatments and all ewes remained clinically healthy until the end of the experiment. Results suggest that Chios ewes exhibit tolerance to Cu supplementation for up to 6 weeks.  相似文献   
69.
The biological implication of the growth hormone/insulin like growth factor-I (GH/IGF-I) axis in canine mammary tumours (CMT) has been recently demonstrated, however its clinical and prognostic implications are unknown. Our aim was to investigate its prognostic significance.Hormonal determinations were done by enzyme immunoassays techniques validated for canine species in serum and tumour tissue from 32 bitches with CMT and in serum and normal mammary tissue from 10 controls. Serum and tissular GH and IGF-I concentrations were significantly higher in the case of malignant tumour compared with benign and controls. GH and IGF-I elevated concentrations were significantly associated with tumour relapse and/or metastases during follow-up and in dogs with reduced survival times; however these parameters were not independent prognostic factors in multivariate analysis. This association demonstrates a link between high serum and intratumoural GH and IGF-I concentrations and a worse prognosis and opens the possibility to new anticancer endocrine therapies in dogs.  相似文献   
70.
采用生物酶法提取林蛙头多糖,应用响应面法对提取工艺进行了优化,分析了提取物对大鼠降血脂的功效。结果表明:林蛙头多糖最佳提取工艺参数为:酶解温度55℃、加酶量2%、林蛙头水溶液质量浓度1∶10 g/mL、酶解时间4.5 h、pH=10.0,此条件下林蛙头多糖得率最高为4.3%;高脂模型大鼠降血脂试验结果显示,林蛙头多糖能明显降低高脂模型大鼠血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)质量浓度,提高血清中高密度脂蛋白胆固醇( HDL-C)质量浓度,对高脂大鼠具有显著的降血脂作用。  相似文献   
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