哲罗鱼的染色体核型分析

以哲罗鱼(Hucho taimen)肾细胞为材料,采用胸腔干燥法制备了染色体,姬姆萨染色和核型分析.结果表明,哲罗鱼的二倍体染色体数目为2n=84,核型公式为:2n=18m 16sm 34st 16t,NF=118.     

不同物种CLPG基因部分序列生物信息分析及山羊染色体电子定位

作者应用比较基因组学和生物信息学方法比较了绵羊、山羊、牛、狗、马、兔子、猪、挪威鼠的CLPG基因部分序列，并对该基因的遗传多样性和遗传分化进行了分析。结果表明，在被比对的12个基因序列中检测到176个多态位点，物种间及物种内的CLPG基因存在较丰富的遗传多样性。通过物种间生物信息分析将CLPG基因定位于山羊21号染色体。     

橙色莫桑比克罗非鱼和荷那龙罗非鱼的染色体核型分析

采用体腔注射PHA-空气干燥法对橙色莫桑比克罗非鱼(Oreochromis mossambicus)和荷那龙罗非鱼(O.hornorum)染色体数量、形态和核型进行了分析和比较。结果显示:两种罗非鱼的二倍体染色体数目均为2n=44,都具有1对特大的染色体,未发现中部着丝粒染色体对和异型染色体。两种罗非鱼的染色体组型形态基本相似,它们的核型公式为2n=44,6sm+24st+14t,NF=50,用常规染色体染色的方法难以区分。研究结果表明,这两种罗非鱼的常规核型差异不显著,在分类地位上非常接近。     

Estimation of the mode of inheritance of thermal tolerance in the guppy <Emphasis Type="Italic">Poecilia reticulata</Emphasis>

High water temperature influences the survival, growth, and maturation of fish. Genetically characterizing thermal tolerance is one of the most important subjects in fish culture. To identify the genetic characterization of thermal tolerance, this characteristic was compared among strains, and among parents and their offspring, in the guppy Poecilia reticulata. In the strain comparison, significant differences in survival rate were observed among the five strains examined, and between females and males. Females exhibited greater tolerance than males in four of five strains examined. In the comparison between parents and their offspring, stronger influence of female parent than of male parent was observed. Offspring obtained from surviving females exhibited greater tolerance than those from dead females. This tendency was typically observed in male offspring. The survival rate in male offspring obtained from dead female parents was lower than that of those from surviving females. The high-temperature tolerance of male parents did not influence this characteristic in offspring as strongly as that of female parents. These results suggest that the major gene or genes, which has a dominant resistant allele and a recessive sensitive allele, are probably passed on by sex-linked inheritance, located on the X chromosome.     

板式家具部件的封边工艺及刀具配置

结合典型封边机,介绍板式家具部件的封边工艺和刀具配置,分析各工序的作用、特点及刀具.     

澳洲宝石鲈染色体核型分析

对5尾澳洲宝石鲈(Scortum bacoo)87个中期分裂相进行了显微计数和测量。结果显示:澳洲宝石鲈染色体数目为2 n=48,其中有2对为中部着丝粒染色体,其余22对为端部着丝粒染色体,其核型公式为2 n=4 m+44 t,NF=52。澳洲宝石鲈染色体大小的绝对值为(1.19±0.16)μm~(3.37±0.28)μm,平均长度为(2.31±0.17)μm。24对染色体相对长度大小差异较显著,平均值为4.17±0.08。     

德国豪赛尔全自动封边机——一款兼容PUR胶水又可以喷胶的封边机

介绍了德国豪赛尔研发的全自动封边机的组成及性能特点。     

洞庭湖土鲶染色体核型分析

采用PHA 和秋水仙素体内注射法,研究洞庭湖土鲶的染色体核型.试验结果表明,洞庭湖土鲶染色体组由58 条组成,按着丝粒位置可分为4组,m 组有12对染色体,sm 组有8 对染色体,st 组有7 对染色体,t 组有2对染色体,每个染色体均有相应的同源染色体.洞庭湖土鲶的2n=58,NF =98,其核型公式为:2n =24m+16sm+14st+4t.     

野生二倍体鸭茅染色体加倍及杂交利用研究

对滇中朗目山野生二倍体鸭茅用秋水仙素处理萌动种子，获得了混倍体鸭茅(同一植株根尖中二倍体细胞和四倍体细胞混存)，混倍体鸭茅的形态学特征及生长发育均与二倍体无明显差异；从混倍体鸭茅自然传粉后代中，获得了纯合同源四倍体鸭茅。同源四倍体鸭茅的气孔和种子均较二倍体大，但形态、发育与二倍体差异较小。以诱导所得混倍体为母本，与四倍体栽培种杂交，杂交F1代为四倍体，其形态学特征及物候发育均介于野生二倍体和四倍体栽培种之间，早期生长与四倍体栽培种相当，优于野生二倍体，繁殖性能与野生二倍体相当，强于四倍体栽培种，分蘖、再生性及干物质产量均强于二倍体，但明显不如四倍体栽培种。以鸭茅野生二倍体为母本，与四倍体栽培种进行杂交，获得的杂交三倍体高度不孕，但早期生长、分蘖、再生等明显优于母本二倍体，杂交三倍体开放传粉后代倍性复杂，混倍体、四倍体和五倍体都有。     

石鲽染色体核型分析

以石鲽(Kareius bicoloratus)成鱼为材料,采用外周血淋巴细胞培养法制备染色体标本,经Giemsa染色,拍照后进行核型分析。结果表明:石鲽的染色体核型为2n=48,48t,染色体臂数为NF=48,未发现多倍体现象,也未发现性染色体和随体。