基于MATLAB的空间7R机构位置分析的新方法

利用向量回转法和MATLAB软件对空间7R机构位置问题进行了分析研究，确定了各杆长和副长方向的单位向量，列出了机构的向量封闭方程，以及各杆位置方程；调用MATLAB矩阵运算函数和解非线性方程组函数，解出了其他各杆的位置与主动件输入角度的关系，以及任何一杆上任意点的空间轨迹，并利用绘图函数表达各杆的位置曲线及任意点的轨迹。实例分析证明所提出的方法是可靠的。     

加工型甘薯良种龙岩7-3的选育及其加工利用

龙岩7—3自育成以来，至今还在全国各地大面积推广应用，表现出高产、稳产、适应性广和商品性好等特点。该品种在福建连城县甘薯种植1万多公顷中占80％，是龙岩连城县地瓜干最主要的原材料来源。文中介绍了其选育、特征特性及加工利用。     

Investigation and genetic mapping of a Glomerella leaf spot resistance locus in apple

Apple Glomerella leaf spot (GLS) is a severe fungal disease that damages apple leaves during the summer in China. Breeding new apple varieties that are resistant to the disease is considered the best way of controlling GLS. Fine mapping and tightly linked marker are critically essential for the preselection of resistant seedlings. In this study, a population of 207 F₁ individuals derived from a cross between ‘Golden Delicious’ and ‘Fuji’ was used to construct a fine simple sequence repeat (SSR)‐based genetic linkage map. The position of R_gls, a locus responsible for resistance to GLS, was identified on apple linkage group (LG) 15 using SSR markers CH05g05 and CH01d08, which was adapted from a published set of 300 SSR markers that were developed using the bulked segregant analysis (BSA) method. These two SSR markers flanked the gene, and its recombination rate was 8.7% and 23.2%, respectively. A total of 276 newly developed SSR markers around the target region and designed from the genome apple assembly contig of LG15 were screened. Only nine of these were determined to be linked to the R_gls locus. Thus, a total of 11 SSR markers were in linkage with R_gls, and mapped at distances ranging from 0.5 to 33.8 cM. The closest marker to the R_gls locus was S0405127, which showed a genetic distance of approximately 0.5 cM. The first mapping of the gene R_gls was constructed, and the locations of the 11 effective primers in the ‘Golden Delicious’ apple genome sequence were anchored. This result facilitates better understanding of the molecular mechanisms underlying the trait of resistance to GLS and could be used in improving the breeding efficiency of GLS‐resistant apple varieties.     

固氮球形芽孢杆菌与巨大芽孢杆菌的混合增效作用

球形芽孢杆菌Bs7与巨大芽孢杆菌Bm1 0 1混合培养时具有固氮增效作用。稀释 40 0倍的巨大芽孢杆菌的无菌上清液与球形芽孢杆菌共培养 ,同样能增强后者的固氮活性。Bs7(pAB5 76 )在纯培养时的nifA表达活性为 6 849 5Miller单位 ,与巨大芽孢杆菌上清培养液进行混合培养时的表达活性为 75 0 0 4Miller单位。上述结果表明 :某些微量非碳源的活性分泌物和某些固氮调节基因可能在固氮增效作用中起重要作用。在与水稻联合培养条件下 ,混合接种球形芽孢杆菌与巨大芽孢杆菌可以提高固氮菌在水稻根表的定殖能力     

新梨七号茎段组织培养再生植株的研究

从植物生长调节物质的不同配比、不同部位诱导不定芽以及炼苗移栽等几个方面对新梨七号离体茎段再生进行研究,获得茎段产生愈伤组织及不定芽再生的适宜培养基,分析以上因素对新梨七号再生体系建立的影响。结果表明,新梨七号的茎段最适宜愈伤诱导培养基为MS+2,4-D 1.0mg/L+6-BA 0.5mg/L,愈伤组织诱导率为100%;茎段诱导不定芽的最佳培养基为MS+6-BA 1.0mg/L+NAA 0.5mg/L,诱导率为95%,增殖倍数为7.29;最适宜不定芽生根培养基为1/2MS+IBA 2.5mg/L+蔗糖15g/L,生根率为90%;封口炼苗时间14d为最好,移栽时间7月最佳。     

转LeFAD7基因番茄干旱胁迫下抗氧化酶活性的研究

通过对干旱条件下转LeFAD7基因番茄和野生型番茄抗氧化酶活性的试验研究,结果表明,转基因番茄在干旱胁迫下叶片水势和抗氧化酶(SOD,POD,CAT)活性较高,MDA含量较低,抗旱性强.     

AQP7基因内含子4多态性与郏县红牛生长性状的关联分析

本试验旨在研究郏县红牛AQP7基因内含子4的遗传变异,分析其遗传多态性对生长性状的影响。采用PCR-SSCP、DNA序列分析及生物信息学技术探讨郏县红牛AQP7基因内含子4的多态性及其与生长性状的关联情况。结果发现,郏县红牛AQP7基因内含子4存在A、B、C 3个等位基因,其基因频率依次为0.838、0.076、0.086;郏县红牛AQP7基因4种不同基因型与其体重和胸围有显著相关(P< 0.05),与其他指标不存在相关性(P> 0.05),且BC基因型个体的体重和胸围均显著大于其他3种基因型(P< 0.05)。暗示BC基因型是提高郏县红牛生长性状的有利基因型,AQP7基因内含子4的遗传多态性与郏县红牛的生长性状存在相关,因此可作为该品种生长性状分子标记辅助选择的候选基因。     

牛源犬新孢子虫NcGRA7基因的克隆及原核表达分析

为了解牛源犬新孢子虫NcGRA7基因的生物学特性,本实验采用PCR技术扩增牛源犬新孢子虫NcGRA7基因,并连接至pMD-18T载体中,构建重组质粒pMD 18-NcGRA7,经PCR、酶切鉴定及测序分析,将NcGRA7基因连接到原核表达载体pGEX-4T-1中,构建重组表达质粒pGEX-NcGRA7,转化大肠杆菌BL21,筛选阳性克隆,将PCR和酶切鉴定正确的重组质粒进行IPTG诱导表达,SDS-PAGE和westem blot分析表达产物.结果表明,扩增的NcGRA7基因片段大小为701 bp,编码233个氨基酸,与GenBank中登录的NcGRA7(AF176649)核苷酸序列同源性为98.7％;western blot分析表达蛋白的分子量为52 ku,具有较好的反应原性.本实验为犬新孢子虫NcGRA7基因疫苗研究奠定了基础.     

Expression and functional analysis of chemokine receptor 7 in canine lymphoma cell lines

C-C chemokine receptor 7 (CCR7) contributes to cell homing to lymph nodes (LNs). Recent studies reported that CCR7 is also expressed in tumor cells, which correlates with LN metastasis in various cancers. However, the expression of CCR7 in tumor cells is unknown in dogs due to the lack of appropriate antibodies. In the present study, a fusion protein of C-C chemokine ligand 19 (CCL19) was employed as an alternative method to CCR7 antibodies. The fusion CCL19 protein specifically detected CCR7 expressed in canine lymphoma cell lines, which showed active chemotaxis to both canine and mouse ligands. The present study will help further research on the involvement of canine CCR7 in LN metastasis.     

茄子新品种渝茄7号的选育

渝茄7号是以自交系897-5为母本,以自交系896-1-1为父本配制而成的茄子一代杂种.晚熟,始花节位为第13～14节,定植至始收65 d(天)左右;植株生长势强,株高130 cm左右,开展度70 cm左右;果实粗棒形,纵径约31 cm,横径约7.3 cm,平均单果质量350 g,果皮深紫黑色,果萼下绿白色,果肉绿白色...