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101.
MUC4 and MUC13 genes as important candidate genes for enterotoxigenic Escherichia coil (ETEC) F4 resistance,may play an important role in the process of against ETEC F18 infection in weaned piglets. In this study,ETEC F18-resistant and -sensitive weaned Meishan piglets were used,and the expression levels of MUC4 and MUC13 genes in 11 tissues (heart,liver,spleen,lung,kidney,stomach,muscle,thymus,lymph nodes,duodenum and jejunum) were determined by quantitative Real-time PCR. The results showed that MUC4 and MUC13 genes were broadly expressed with different expression levels in all the 11 tissues. In the thymus and lymph tissues,the expression of MUC4 gene in resistant piglets was significantly higher than that in sensitive piglets (P<0.05);In the lung tissue,theMUC13 gene expression level in resistant individuals was significantly higher than that in sensitive individuals (P<0.05),and in the intestinal tissues of duodenum and jejunum, the expression level of MUC13 gene was relatively higher in resistant individuals. Thus we speculated that the high expression of MUC4 gene in immune tissues and MUC13 gene in intestinal tissues might improve the immune ability of piglets,protect and lubricate the intestinal tract, and resist ETEC F18 infection.  相似文献   
102.
Porcine alpha (1,2) fucosyltransferase (FUT2) gene was importance in glycosphingolipid biosynthesis-globo series, potentially played a regulatory role during Escherichia coli (E. coli) F18 infection process in weaned piglets. In order to explore sequence structure of porcine FUT2 gene and its biological function, this test amplified FUT2 gene CDS sequence of Dongchuan pigs by PCR, forecasted and analyzed the protein sequences and functional regions of FUT2 gene, its expression level was detected in 11 tissues of 8 Dongchuan weaned piglets in 35 days old at the meantime. The results showed that the CDS sequence of FUT2 gene was 1 023 bp, which encoded 340 amino acids. FUT2 protein was fat-soluble hydrophilic protein, which the structure was not stable, including a transmembrane helix structure, but without signal peptide that suggested the FUT2 protein was a membrane protein;FUT2 protein included 2 N-glycosylation sites (No. 185 and No. 305 amino acids), without O-glycosylation sites, there were 14 potential phosphorylation sites, included 6 Ser, 2 Thr and 6 Tyr, analyzing the functional regions found that the FUT2 protein had a superfamily of conserved domains:FUT1-FUT2-like (58-319 amino acids). The phylogenetic tree result showed that the relative relationship between swine and cattle was relatively close, but was distant from chimpanzee, human, mouse and rat. FUT2 gene was expressed in all 11 tissues of Dongchuan weaned piglets, there were higher expression in digestive tract and immune tissues. The present results suggested that FUT2 gene might play a role to resistance to E. coli F18 in weaned piglets, and might indirectly against E. coli F18 through the synthesis of fucosyltransferase.  相似文献   
103.
保护性耕作技术及配套机具已成为当今世界农业发展的主题,深松技术作为保护性耕作的一项关键技术在我国已得到广泛应用。为此,进行了浅翻深松翻转犁的总体设计,确定了工作原理和主要参数,并通过试验进行了验证。结果表明:该样机达到了设计指标,具有一定的应用价值。  相似文献   
104.
锰肥对孜然芹产量的影响   总被引:2,自引:2,他引:0  
通过对孜然芹种子使用0.05%.0.10%,0.50%,1.00%4个浓度的MnSO4进行浸种处理,结果表明,用0.05%和0.10%的MnSO4溶液浸种增产效果显著,增产幅度分别为46%和28%,而0.5%和1.0%的处理均无增产效果。  相似文献   
105.
根据大量调查统计数据和汽车市场变化规律 ,分析目前国内外 (尤其是国内 )汽车市场情况和发展趋势 ,并对 2 0 10年国内汽车市场主要产品和技术需求进行了预测。  相似文献   
106.
甜橙新品种——桂橙一号的选育   总被引:4,自引:0,他引:4  
桂橙一号是冰糖橙优良芽变株系,成熟期11月下旬,平均单果质量154.0g,大小较均匀,可食率75.66%,可溶性固形物含量14.6%,全糖12.47%,酸0.38%,风味浓郁,有蜜香,甜脆化渣,树形开张,丰产稳产,商品性好,适应性强,果实耐贮藏。  相似文献   
107.
构建基于ArcGIS的林业工程信息系统   总被引:1,自引:0,他引:1  
从提高林业工程数据管理的效率、效果和效益出发,探讨构建基于ArcGIS的县级林业工程信息系统的方法和步骤,以期为建立多层级互联共享的林业工程信息系统储备基础数据和相关技术。  相似文献   
108.
长叶榧叶部油挥发性成分的色谱/质谱分析研究   总被引:1,自引:0,他引:1  
采用气相色谱/质谱(GC-MS)联用法测定了长叶榧叶部精油的挥发性成分,初步发现其主要成分是柠檬烯、反式α-蒎烯、β-蒎烯、顺式α-蒎烯、3-莰烯、6,6-二甲基-2-亚甲基-环庚烷、β-月桂烯,其含量分别为32.2%、12.5%、7.1%、6.6%、6.6%、5.5%、4.4%.  相似文献   
109.
都市农业是在城郊农业内部产生和发展起来的。都市农业与城郊农业在其生长地域、功能、以及产业布局等十个方面存在重要的内在联系和转变接点。  相似文献   
110.
狗牙根种质资源及遗传多样性的研究概况   总被引:7,自引:0,他引:7  
介绍了国内外狗牙根种质资源的研究概况;从形态学水平、染色体水平、蛋白质水平、DNA水平对狗牙根的遗传多样性进行概述,并对存在的问题提出建议。  相似文献   
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