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31.
以CP23重组蛋白为抗原建立检测微小隐孢子虫抗体间接ELISA方法的研究 总被引:3,自引:0,他引:3
摘要:以在E.coli高效表达的微小隐孢子虫子孢子表面抗原CP23为抗原,以辣根过氧化物酶(HRP)标记的山羊抗鼠IgG为二抗,建立了检测微小隐孢子虫抗体的间接ELISA方法。经检测筛选出最佳反应条件为1μg/孔纯化的E.coli表达的CP23抗原包被酶标板,用10%免血清进行封闭,以正常E.coli裂解上清液稀释待检血清。实验表明应用CP23重组蛋白作为诊断C.parvum抗原具有特异性高、抗原易纯化和成本低等特点。 相似文献
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33.
遗传背景对水稻无融合生殖材料C1001双胚苗频率影响的研究 总被引:1,自引:0,他引:1
同核异质雄性不育材料与无融合生殖材料C1001B杂交和回交表明,C1001B的双胚苗,是受核基因控制的性状,双胚苗频率的表达,具明显的胞质效应和胞核效应,在胞质效应中,不育胞质与可质胞质的差异尤其显著,不育胞质对双胚苗的表现有明显的抑制作用,不同世代间胞质效应和胞核效应的表现也不一致。此外,环境条件对C1001的双胚苗表现有一定的影响。 相似文献
34.
N. Katoh 《Veterinary research communications》1994,18(6):423-432
Protein kinase C (PKC) activity was evaluated and the phosphorylation of its endogenous substrates was explored in fatty liver induced by administration of ethionine (an analogue of methionine) to cows in order to assess the relevance of PKC-dependent phosphorylation in the development of fatty liver. PKC activity was decreased in both the cytosolic and the total particulate fractions from fatty livers, compared to the corresponding fractions from control liver. The mode of activation by the PKC cofactors (1-oleoyl-2-acetyl-sn-glycerol, 12-O-tetradecanoylphorbol-13-acetate, phosphatidylserine and Ca2+) was similar in both control and fatty livers, suggesting a quantitative but not a qualitative change in PKC in fatty liver. At least three substrate proteins (34 kDa, 26 kDa and 19 kDa) were found in the cytosolic fraction and their phosphorylation was reduced in fatty liver. These results suggest that impairment of the signal transduction pathway mediated by PKC is involved in the pathogenesis of fatty liver in cows.Abbreviations ATP
adenosine triphosphate
- EGTA
ethylene glycol bis(-aminoethylether)-N,N,N,N-tetraacetic acid
- NEFA
non-esterified fatty acid
- OAG
1-oleoyl-2-acetyl-sn-glycerol
- PKC
protein kinase C
- PS
phosphatidylserine
- SDS-PAGE
sodium dodecyl sulphate-polyacrylamide gel electrophoresis
- TG
triglyceride
- TPA
12-O-tetradecanoylphorbol-13-acetate 相似文献
35.
根据绵羊的营养参数和饲养标准,结合日增重水平,计算了不同日增重水平对应的体重月平均动态及其所对应的粗蛋白日需要量和代谢能日需要量。不同日增重水平,达到生长期望所需要的日数不同,日增重水平越高,达到生长期望总所需要的粗蛋白和代谢能越少,但月平均的日需要量越多。自由放养的东北细毛羊当年生羔羊的日增重水平仅相当于舍饲饲养日增重的100g水平,根据代谢能计算,年总需干草340kg,可以作为计算载畜量的基本参数。自由放养情况下,即使能量满足需要,粗蛋白也短缺。当年生羔羊日增重在150 ̄200g,9 ̄10月龄内体重达到46 ̄50kg是北方草地家畜生产的理想目标,通过补饲可以实现。 相似文献
36.
C肉毒杀鼠素在高寒草甸地区灭鼠技术中的应用 总被引:2,自引:0,他引:2
综述C肉毒杀鼠素草原灭鼠应用技术,充分肯定了C肉毒杀鼠素毒力强、适口性好、对非靶动物毒性低、作用缓慢、无二次中毒、易降解和适合规模灭鼠的特点,为鼠害防治提供了新的思路。 相似文献
37.
38.
中国香瓜与菜瓜地方品种资源白粉病抗性评价 总被引:5,自引:0,他引:5
春秋2个季节在温室利用风媒接种方法对搜集的102份香瓜和14份菜瓜种质资源进行了白粉病抗性评价,结果鉴定出7份香瓜和1份菜瓜高抗白粉病,其病情指数为零,1份菜瓜抗病,其病情指数0.9,表明我国香瓜和菜瓜地方品种资源中蕴涵着潜在的改良甜瓜白粉病抗性的基因资源。 相似文献
39.
AIM:To explore the effects of PMA(phorbol-12-myristate-13-acetate, a tumor promoter, mimicking the action of diacylglycerol on PKC)and laminin on the adhesion and the proliferation of human hepatocellular carcinoma cells, and provide a new clue to liver cancer treatment.METHODS:Human hepatocellular carcinoma cell line(BEL-7402)was used to identify the endogenous laminin and protein kinase C-α(PKC-α) expression, and the effects of laminin and PMA on the adhesion and the proliferation were also investigatedin vitro.RESULTS:By the effect of exogenous laminin, human hepatocellular carcinoma cell (BEL-7402) possessed endogenous laminin expression and increased the adhesion and the proliferation, which was showed the synergistic action by the effect of PMA in combination. By the action of PMA alone, the proliferation and the PKC-α expression increased by exogenous laminin were decreased, and the adhesion and the endogenous laminin expression were increased.CONCLUSIONS:The finding suggested that the adhesion and the proliferation of human hepatocellular carcinoma cell were closely related to the effects of endogenous or exogenous laminin, which were associated with cPKC-α activity. Therefore, the application of anti-laminin antibody in combination with PKC antagonist might be a new clue to find out the therapy for liver cancer. 相似文献
40.
AIM:To observe the dynamic changes of expression of PKCα, TGF-β1 and α-SMA in glomeruli of diabetic rats induced by the alloxon and to invesitigate their roles in the diabetic nephropathy(DN).METHODS:Rats were randomly divided into four groups: normal control group (group A), diabetic group of one week (group B), diabetic group of one month (group C), diabetic group of two months (group D). Immunohistochemistry and Western blotting were used to detect the expression of PKCα, TGF-β1 and α-SMA in renal tissue of all groups. Blood glucose, triglycerides, cholesterol, creatinine and urine protein were analysed by chemical methods. The morphological changes of renal tissue were checked through microscopy.RESULTS:The expression of PKCα and TGF-β1 in renal tissue of diabetic groups were increased comparing with those of nomal control group(P<0.05). The mesangial cells expressed α-SMA in two months group. Chronologically the expression of PKCα, TGF-β1 and α-SMA were positively correlative with each other and the impairment of kidney was also observed.CONCLUSIONS: During the DN process the expression of PKCα increased. PKCα raised GFR and the permeability of glomerular filtration membrane which enhanced urinary albumin excretion. PKCα also increased expression of TGF-β and therefore to induce the expression of α-SMA. The appearance of α-SMA was a marker of the phenotypic transform of renal cells. 相似文献