猪CD8β基因的克隆、表达及其结构与功能分析

本研究应用RT-PCR技术,从猪胸腺细胞总RNA中扩增、克隆了猪CD8β基因,序列分析表明CD8β含621 bp的开放阅读框,编码207个氨基酸,与NCBI/GeneBank已发表的参考基因的核苷酸及推导氨基酸序列的同源性分别为97.8%和96.8%,与人、小鼠和鸡CD8B蛋白的氨基酸同源性分别为75.7%、67.9%和33.3%.根据大肠杆菌密码子偏嗜性改造目的基因,构建了pET28a/PCD8 β原核表达系统,并经诱导获得高效表达的分子量为24 ku的重组蛋白(rPCD8 β),表达量占菌体蛋白总量的30%.利用生物信息学和分子生物学软件对猪CD8 β基因编码的蛋白进行结构预测,表明猪CD8 β成熟蛋白为跨膜蛋白,其中172aa在胞外区,22aa在跨膜区,10aa在胞内区;蛋白骨架内含有较多的柔性区域,而且分布不均匀.能形成结构松散的球状蛋白;猪CD8 β分子V区三维结构与鼠的具有非常相似的空间结构,与人的差别较大,这为猪CD8B蛋白结构与功能的进一步研究奠定了基础.     

农民权益保障与土地征用价格确定——以威海市环翠区为例

征地价格是征地问题的核心,也是征地制度改革的关键。以山东省威海市环翠区耕地征用为例,根据其近年的投入产出水平,采用收益还原法和市场交易资料修正法,同时考虑当地人均耕地数量、土地供求关系、经济发展水平及农用地的社会保障作用等因素,综合确定环翠区耕地的征用价格,并与现行补偿标准进行了对比分析。     

彩叶树种叶片中花青素含量的测定

采用一种简单快速的紫外-分光光度方法提取和测定了彩叶树木紫叶矮樱、红宝石海棠叶片中花青素的含量.结果表明:彩叶树木叶片呈色起主导作用的花青素随光照、季节温度、酸碱度等环境条件的变化而变化[1],在光照充足、温度较低、酸性土壤的环境条件下,叶片色泽绚丽.     

Evaluating of the Association Between Early-stage Weight and Gut Microbiota in Duroc Pigs Using 16S rRNA Sequencing

The purpose of this study was to explore the possible association of the intestinal microbiome with early-stage weight in Duroc pigs.80 days old weaned piglets with Lighter body weight (LBW,n=9) and heavier body weight (HBW,n=9) were selected from 91 individuals based on their body weights ranked.Fecal samples from piglets in the early grower phase were performed for microbial diversity,composition and predicted functionality by sequencing the V3-V4 region of 16S rRNA gene.The results showed that there was no significant differences in microbial Alpha diversity between HBW and LBW groups(P>0.05).The two dominant phyla detected in both groups were Firmicutes (65.62% and 66.57% in HBW and LBW groups) and Bacteroidetes (30.87% and 29.80% in HBW and LBW groups).Four dominant genera were Prevotella (23.82% and 20.84% in HBW and LBW groups),Lactobacillus (9.11% and 16.55% in HBW and LBW groups),norank_f_Ruminococcaceae (10.32% and 9.98% in HBW and LBW groups),and norank_f_Lachnospiraceae (6.33% and 4.53% in HBW and LBW groups).PCoA analysis showed that there were small differences in gut microbes among Duroc piglets,whereas,some weight-associated microbial compositional differences were revealed between HBW and LBW groups.At the genus level,the abundance of several genera,such as g_Kitasatospora,g_norank_o_Tremblayales,g_norank_f_Erysipelotrichaceae,g_unclassified_f_[Paraprevotellaceae] and g_Coprobacillus,were significantly higher in HBW group than in LBW group (P<0.05).The abundance of Corynebacterium in LBW group was significantly higher than that in HBW group (P<0.05).Moreover,the KEGG pathways analysis showed that the sesquiterpenoid biosynthesis,insulin signaling pathway,ascorbate and aldarate metabolism,and biosynthesis of ansamycins were significantly enriched in HBW group (P<0.05),however,the secretion system pathway was significantly enriched in LBW group (P<0.05).These results might provide insights into host-microbe interactions occurring in the early stage piglets and would be useful in contributing to healthy pig breeding.     

秋季油松雪倒原因分析及其推论

利用静力学模型建立树体力矩平衡方程,分析甘肃省兴隆山自然保护区麻家寺秋季油松雪倒现象,提出雪倒三大成因为土体抗剪强度、根系生长分布特征和偏冠,郁闭林分中他感作用则是导致偏冠的主要因素,并分析指出他感作用还会导致根系呈偏态分布,进一步加重雪倒危险。进而推论分析了树木抗雪倒、风倒的形态特征,以及坡面泥石流起动机制。     

晚籼优质稻家福香1号的选育及栽培

家福香1号系玉林市农业科学研究所利用桂丝占作母本,丰华占作父本进行杂交选育而成的晚籼中熟优质稻新品种,于2009年3月通过广西农作物品种审定。该品种生育期120 d、株高102.3 cm、结实率87.93%、千粒重24.4 g、平均单产7125.0 kg/ha,其11项品质性状指标达农业部颁优质米二级标准,适宜在桂南、桂中稻区作晚稻种植。家福香1号栽培技术要点：稀播培育多蘖壮秧;适时移栽,合理密植;合理施肥,科学管水;综合防治病虫害等。     

Research Progress on Application and Safety of Soybean Isoflavone in Animal Husbandry

Soybean isoflavone is a kind of faint estrogen-like mixture of polyphenols which derived from the leguminous plants.Its active components include genistein,daidzein and glycitein.It is used in animal husbandry for its physiological functions that it can enhances performance,immune function,antioxidant and improves bone metabolism.But some following reports about safety and side effects of soybean isoflavones are also appeared.That is a worthy further research topic how to use it effectively.The article summarizes the types of soybean isoflavones,nutrient metabolism characteristics,physiological characteristics,the promoting effect of livestock and poultry production and security problems about animal and human.     

咖啡的精品时代

本世纪全球咖啡产业已经进入"精品"和"4C"等认证时代。中国的咖啡产业历经60余年的规模化发展,特别是云南省近20余年的规模化种植,小粒种商品咖啡豆的质量已经被国内外客商知晓。"十二五"云南的咖啡产业进入大发展阶段,普洱和临沧两市将新增种植面积6.67万hm2。今后各种植区在生产大宗商品豆的同时,可在局部种植生产"精品"商品豆,以提升云南咖啡在国际上的话语权,增加种植户的经济收入。     

猕猴桃分子生物学研究进展

本文综述了猕猴桃的核酸提取、基因克隆和分子标记研究进展。重点介绍相关功能基因在延缓果实衰老、提升果实品质及分子标记技术在品种鉴定、亲缘关系分析中的应用。     

油茶单芽组培生根研究

采用基本培养基、培养温度、光照强度、单芽形态和激素等因素对油茶岑软2号无性系组培苗生根影响的筛选试验。结果表明,1/2ER为油茶组织培养最适基本培养基;ABT60.5 mg/L＋IAA 2.0 mg/L＋NAA0.8 mg/L为最优的激素浓度组合,组培单芽培养40天生根率达93.7%,每个单芽长根3～4条;在室温28℃±2℃,光强2 500～3 500 Lx条件下利于油茶组培苗的生根,生根率高达97.8%。