Chromosomal aberrations in a population of ground squirrels

Chromosomes were analyzed from a population of Spermophilus beldingi that included an adult female and three juveniles from the same burrow. All animals had a diploid number of 30. The adult and a juvenile female from the burrow had identical aberrant karyotypes containing an unpaired submetacentric and a minute metacentric chromosome. A familial aberration involving an X chromosome, without phenotypic alteration, is most probable.     

Chromosomal translocation in domestic fowl induced by x-rays

The effect of x-rays at various voltages and intensities, with monochromatic and polychromatic beams, on Ektachrome daylight and artificial-light film was investigated. The colors were rated according to the Munsell color system and ranged over all the spectrum except red. The color in terms of hue, value, saturation, and chroma was a function of wavelength as well as intensity, and thus the method may be useful in dosimetry as well as in radiography. Microradiographs of metals and wood were remarkable in showing detail not obtainable with conventional black-and-white photographic emulsions.     

Chromosomal breakage induced by extracts of human allogeneic lymphocytes

A high frequency of chromosomal breakage and rearrangement has been found in fibroblasts treated with extracts of allogeneic human lymphocytes. The fact that these changes were not observed when extracts of autologous lymphocytes were tested indicates that mechanisms involving self-recognition are operative. Abnormalities, such as chromosome lagging and bridges, occurring in anaphase were also served.     

更生霉素诱发蚕豆染色体畸变的研究

本实验利用更生霉素诱发蚕豆染色体畸变,实验结果表明:更生霉素诱发蚕豆染色体畸变的频率高于EMS处理,具有较强的诱变作用。     

自然四倍体泥鳅雄核发育二倍体染色体组构成研究

为探究鱼类雄核发育新途径及自然四倍体泥鳅所产生的配子染色体组构成,采用自然四倍体泥鳅(4n=100)为父本、二倍体泥鳅(2n=50)为母本进行杂交,受精后5 min将受精卵放入3℃水中处理60 min诱导雄核发育二倍体泥鳅,并对其后代的血红细胞核体积、染色体核型、Ag-NORs带型及荧光原位杂交(FISH)信号等进行了研究。结果表明:对照组杂交三倍体泥鳅血红细胞核体积为(38.29±3.14)μm³,处理组雄核发育二倍体泥鳅血红细胞核体积为(27.92±3.58)μm3,处理组雄核发育二倍体泥鳅血红细胞核体积为(27.92±3.58)μm³,二者血红细胞核体积之比为1.37∶1;杂交三倍体泥鳅胚胎染色体数目3n=75,核型公式为15m+6sm+54t, NF=96,雄核发育二倍体泥鳅胚胎染色体数目2n=50,核型公式为10m+4sm+36t, NF=64;杂交三倍体泥鳅胚胎染色体中,在3个染色体短臂的端部检测到3个FISH杂交信号,雄核发育二倍体泥鳅胚胎染色体中,在2个染色体短臂的端部检测到2个FISH杂交信号;杂交三倍体泥鳅染色体和间期核中,呈现出Ag-NORs数目为1～3个,雄核发育二倍体泥鳅胚胎染色体和间期核中,呈现出Ag-NORs数目为1～2个。研究表明,雄核发育二倍体泥鳅的染色体组构成为2套染色体组,表明自然四倍体雄性泥鳅能产生二倍体(2n)配子,该结果为自然四倍体雄性泥鳅是具有4套染色体组的遗传四倍体提供了重要的遗传学证据。     

自然四倍体泥鳅雄核发育二倍体染色体组构成研究

为探究鱼类雄核发育新途径及自然四倍体泥鳅所产生的配子染色体组构成,采用自然四倍体泥鳅(4n=100)为父本、二倍体泥鳅(2n=50)为母本进行杂交,受精后5 min将受精卵放入3℃水中处理60 min诱导雄核发育二倍体泥鳅,并对其后代的血红细胞核体积、染色体核型、Ag-NORs带型及荧光原位杂交(FISH)信号等进行了研究。结果表明:对照组杂交三倍体泥鳅血红细胞核体积为(38.29±3.14)μm³,处理组雄核发育二倍体泥鳅血红细胞核体积为(27.92±3.58)μm³,二者血红细胞核体积之比为1.37∶1;杂交三倍体泥鳅胚胎染色体数目3n=75,核型公式为15m+6sm+54t,NF=96,雄核发育二倍体泥鳅胚胎染色体数目2n=50,核型公式为10m+4sm+36t,NF=64;杂交三倍体泥鳅胚胎染色体中,在3个染色体短臂的端部检测到3个FISH杂交信号,雄核发育二倍体泥鳅胚胎染色体中,在2个染色体短臂的端部检测到2个FISH杂交信号;杂交三倍体泥鳅染色体和间期核中,呈现出Ag-NORs数目为1~3个,雄核发育二倍体泥鳅胚胎染色体和间期核中,呈现出Ag-NORs数目为1~2个。研究表明,雄核发育二倍体泥鳅的染色体组构成为2套染色体组,表明自然四倍体雄性泥鳅能产生二倍体(2n)配子,该结果为自然四倍体雄性泥鳅是具有4套染色体组的遗传四倍体提供了重要的遗传学证据。     

2005年至2006年优质啤酒大麦品种比较试验

通过在大理州弥渡县的8个优质啤酒大麦品种比较试验，筛选出与墨西哥500号同样高产的甘早5号，该品种产量5503．5kg／hm^2，千粒重42．6g，可作为优质啤酒大麦在大理州推广种植，满足当地麦芽厂对优质啤酒大麦原料的需求。     

Cloning and characterization of a novel barley gene,HvORG4,induced by Fusarium graminearum infection

Barley Fusarium head blight(FHB),caused by species of the Fusarium fungus,is a devastating disease that is reemerging worldwide in recent years.In this study,a novel gene,HvORG4,was cloned from barley by using cDNA library and suppression subtractive hybridization(SSH) library strategies.The SSH library and cDNA library were constructed from the Chinese barley cultivar Jing02-461(resistance to FHB) infected by Fusarium graminearum isolate Huanggang-1.For the SSH analysis,more than 120 differentially express...     

LSD in mice: abnormalities in meiotic chromosomes

Meiotic chromosomes of six mice injected with high doses of lysergic acid diethylamide (LSD-25) and of six controls were studied. Several breaks, gaps, and unidentifiable fragments were found in the treated but, with a few exceptions, not in the control animals. Secondary constrictions were more numerous in the treated than in the untreated mice. Possible consequences are discussed.     

在兽医科研中应用Excel进行方差分析和多重比较(LSD)

方差分析是兽医科研数据处理的常用数理统计方法之一。以饲料中添加不同钙磷含量对幼猪增重影响为例,介绍在Excel 2003软件中利用“宏”自动进行方差分析,以及利用其函数以最小显著差数进行多重比较。     

用甲基磺酸乙酯(EMS)诱变的大麦浙农大3号突变体的筛选和鉴定

利用化学诱变剂甲基磺酸乙酯(ethyl methane sulfonate,EMS)诱变处理大麦品种浙农大3号的种子,然后种于大田,将获得的M2代材料进行生物学性状与农艺性状鉴定,入选的M3代材料继续进行验证.结果表明,实验获得了幼苗、生育期、叶、茎秆、穗及育性等生物学特性与主要农艺性状的突变体,变异类型丰富,突变群体的表型变异率约为7.46%.本研究构建的突变群体为大麦功能基因组研究奠定了基础,同时为大麦遗传改良提供了重要的材料.     

利用流式细胞术检测甜菜染色体倍性和DNAC-值

[目的]研究流式细胞技术快速、准确、方便测定甜菜体内染色体倍性和DNAC-值,为甜菜染色体倍性、分子生物学领域的相关研究提供参考依据.[方法]以二倍体M39-8-4嫩叶为材料,以已知基因组的新疆野杏洛浦洪待克为外标,建立适合于甜菜染色体倍性和基因组的流式细胞术测定方法.[结果]经7种常用细胞解离液筛选,Marie's为...     

亚精胺处理青稞幼苗对NaCl胁迫作用的缓解

以青稞(Hordeum vulgare L.var.nude)幼苗叶片为试材,以200mmol/L NaCl对其进行盐胁迫,研究了外源亚精胺(Spd)预处理对NaCl胁迫下青稞幼苗叶片相对含水量(RWC)、叶绿体色素与水溶性蛋白质含量的影响。在NaCl胁迫的前两天,NaCl Spd处理组用含0.5mmol/L Spd的1/2Hoagland营养液进行水培和叶面喷施含0.02%土温-80的0.5mmol/L Spd溶液;对照组(CK)和NaCl处理组,用1/2的Hoagland营养液进行水培,叶面喷施含0.02%土温-80的蒸馏水。随着200mmol/L NaCl胁迫的进行,青稞幼苗叶片RWC、叶绿体色素与水溶性蛋白质含量均明显降低,Spd预处理显著延缓了它们的下降。表明Spd预处理缓解了NaCl胁迫对青稞幼苗造成的伤害,具有防衰抗盐的保护作用。     

Chromosomal gene transfer in Spiroplasma citri

The study of resistance marker rearrangement in Spiroplasma citri mutants provides evidence of transfer of chromosomal information followed by recombination. This is the first report of such a transfer in vivo in the mollicutes--that is, in the smallest self-replicating organisms. The double-resistant phenotypes obtained are stable even without selection pressure. The mechanism of gene transfer is insensitive to deoxyribonuclease, requires contact, and possibly, areas of fusion of the cell membranes; it shares properties with the transfer by protoplast fusion in Gram-positive bacteria. The extensive degenerative evolution of mollicutes has retained, in S. citri, bacterial functions of chromosomal transfer and recombination.