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101.
This study used Real-time PCR to detect the changes of expression quantity of claudin 3 (CLDN-3), cytokeratin 8 (KRT8) and mucin 1 (MUC1) three proteins mRNA in IPEC-J2 cells at three different time points.IPEC-J2 cells were infected by TGEV, we explored whether Lactobacillus amylovorus metabolites could enhance cell barrier function by maintaining or improving mRNA expression of CLDN-3, KRT8 and MUC1, whether had effects on the barrier function of IPEC-J2 infected by TGEV.The results showed that mRNA expressions of MUC1, CLDN-3 and KRT8 in the normal cell control group did not change significantly with time (P> 0.05); MRS medium culture group did not change significantly compared to the normal cell control group(P> 0.05); Gene expressions of MUC1, CLDN-3 and KRT8 proteins in Lactobacillus amylovorus metabolites alone treatment group showed significant time-dependent effect (P< 0.05).After being treated 24, 36 and 48 h, gene expressions of MUC1, CLDN-3 and KRT8 proteins in Lactobacillus amylovorus metabolites+TGEV experiment group was significantly higher than virus control group (P< 0.05).Lactobacillus amylovorus metabolites could improve MUC1, CLDN-3 and KRT8 expressions in IPEC-J2 cells, while being able to negatively regulate MUC1, CLDN-3 and KRT8 expressions that TGEV induced in IPEC-J2 cells, thereby inhencing the barrier function of IPEC-J2 cell against TGEV.  相似文献   
102.
In order to research the genetic diversity and phylogenies of Wuzhishan pig, 56 complete mtDNA D-Loop were analyzed.55 sequences were amplified by polymerase chain reaction (PCR) and 1 sequence was downloaded from GenBank.The results showed that repetitive sequence "TTATAAAACAC" appeared in the conservative regions of 21 mtDNA D-Loop sequences.13 haplotypes and 14 variable sites were observed in 56 sequences.Haplotype diversity and nucleotide diversity (Hd =0.838 and Pi=0.00334) indicated that Wuzhishan pig had high genetic diversity.Two branches in the phylogenetic tree and Network analysis diagram indicated that there were two maternal origins in Wuzhishan pig.The phylogenetic tree of Wuzhishan pig and other 23 species showed that Wuzhishan pig had close genetic relationship with the pig breeds in the south region of the Yangtze river.  相似文献   
103.
In this paper through digestive and metabolic experiments studied the voluntary intake and apparent digestibility of cottonseed hulls (kernel-contained CH,kernel-free CH) and cornstalk on sheep to evaluate the nutrition value and digestion characteristics of cottonseed hulls.12 of adult Xinjiang merino rams were selected and divided into two groups (n=6 each group),and on the basis of 300 g/(head·day) of mixed concentrate,fed with kernel-free CH by 400 (group 1) or 800 (group 2) g/(head·day) respectively,to estimate the digestibility of CH by difference method;As well,another 18 of adult Xinjiang merino rams were selected and divided into three groups (n=6 each group),and on the basis of 300 g/(head·day) of mixed concentrate,cafeteria feeding with kernel-contained CH (group 3),kernel-free CH (group 4) or ground cornstalks (group 5) respectively,to study the effects of three diets on the voluntary intake,digestion and metabolism of sheep.The results showed that the apparent digestibility of the DM,OM,CP,cellulose,hemicellulose and energy of kernel-free CH by sheep were 46.71%,47.37%,-53.40%,66.60%,62.48% and 42.59%,respectively.There were no significant differences in the intake of DM,OM,cellulose,hemicellulose,energy and Ca between kernel-contained CH and kernel-free CH groups (P> 0.05);Intake of CP and P in kernel-contained CH group were extremely significantly higher than that in kernel-free CH group (P< 0.01);Intake of lignin in kernel-contained CH group was extremely significantly lower than that in kernel-free CH group (P< 0.01).There were no significant differences in the apparent digestibility of DM,OM and energy between kernel-contained CH and kernel-free CH groups (P> 0.05).The apparent digestibility of cellulose and hemicellulose in kernel-free CH group were significantly and extremely significantly higher than that in kernel-contained CH group (P< 0.05;P< 0.01),respectively.The apparent digestibility of CP in kernel-contained CH group was extremely significantly higher than that in kernel-free CH group (P< 0.01).The apparent digestibility of DM,OM,CP,cellulose and energy in ground cornstalks group were extremely significantly higher than that in kernel-contained CH and kernel-free CH groups (P< 0.01),however,the apparent digestibility of Ca and P were lower than that in kernel-contained CH and kernel-free CH groups (P> 0.05).Intake and retention of nitrogen in kernel-contained CH group were extremely significantly higher than that in kernel-free CH group (P< 0.01);The was no significant difference in the retention of nitrogen between kernel-free diet group and cornstalk diet group (P> 0.05).It was concluded that CH was a kind of special forage with larger intake,higher digestibility on the fiber substances and energy,but with a serious obstruction on protein digestion;The nutritional value between kernel-free diet and cornstalk diet was almost equal,and with lower nitrogen digestibility on kernel-free diet.  相似文献   
104.
白灵菇产木聚糖酶发酵条件的研究   总被引:2,自引:0,他引:2  
通过多因子的摇瓶液体发酵优化试验,以白灵菇为始菌,研究其产木聚糖酶的情况。以甘蔗渣为唯一碳源,来测定处于不同条件下的培养基中的白灵菇所产木聚糖酶的酶活力,同时测定其相应条件下的菌丝体生物量。结果表明:其最适温度为24℃,pH为6.0,接种量为12.5%,摇瓶装液量为60ml/瓶,摇床转速为160rpm,培养天数为7d。最后以各个因子的最佳梯度做优化培养。其发酵液中木聚糖酶活力高达71.342IU/ml,菌丝体生物量也高达1.043g/60ml。  相似文献   
105.
固体水释水规律及其特性的研究   总被引:13,自引:0,他引:13  
固体水是一种集微生物、化学技术为一体的生态环保产品。当固体水与植物根系接触 ,在土壤微生物的作用下 ,逐渐降解释水 ,被植物根系吸收 ,可长期地为植物生长提供水分。本文以油松和侧柏为供试树种 ,研究了固体水的释水规律及影响固体水释放的因素 ,得出了固体水的释水总量、释水速率、日释水高度及固体水的释水量与其接触土壤面积的关系。  相似文献   
106.
四季青中一个新的酚性化合物   总被引:4,自引:0,他引:4  
对冬青科植物冬青干燥叶(四季青)的化学成分进行了研究.取干药材10 kg, 加8倍量体积分数80 %乙醇回流煎煮3次, 每次4 h,回收乙醇至无醇味.浸膏混悬于适量水中,依次用石油醚、乙酸乙酯、正丁醇萃取,回收溶剂.采用不同层析技术进行分离,从正丁醇部位分得1个酚性化合物,经理化及光谱方法鉴定为:3,4-二羟基 -7-(3′-O-β-D-吡喃葡萄糖基 -4′-羟基 -苯甲酰基) -苯甲醇(俗称四季青酚苷),一种新化合物.  相似文献   
107.
杉木优良家系区域测定的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
  相似文献   
108.
四种植物提取物对斜纹夜蛾卵的毒杀效果   总被引:2,自引:1,他引:2  
以斜纹夜蛾卵为研究对象.对雷公藤Tripter gium wilfordii茎、皂荚Gleditsia sinensis Lam.刺、苦参Sophora flavescens和博落茴Macleya cordata等4种植物材料的正已烷及乙酸乙酯提取物的杀卵活性进行了测定。结果表明:博落茴的乙酸乙酯提取物对斜纹夜蛾卵有较好的杀伤力,校正未孵化率高达95.63%;雷公藤的乙酸乙酯提取物和苦参的正已烷提取物对斜纹夜蛾卵的孵化也有明显的抑制作用。  相似文献   
109.
TM卫星影像图在剑河县森林资源二类调查中的应用   总被引:2,自引:0,他引:2  
贵州省 1999年第一次利用TM卫星影像图对剑河县进行森林资源二类调查。详细介绍了调查方法、步骤 ,并进行了判读精度分析 ,对存在的问题 ,提出了改进意见  相似文献   
110.
漆酶催化活性中心结构及其特性研究进展   总被引:22,自引:3,他引:22  
漆酶是一种多酚氧化酶,参与木质素的降解或聚合,具有氧化木质素的能力,但不同来源的漆酶其氧化降解木质素的能力相差很大。漆酶的结构决定了漆酶的特性,因而也就决定了漆酶氧化降解木质素的能力。本文综述了近10年来漆酶分子催化活性中心的结构与功能及其特性的研究进展。  相似文献   
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