MIXED MODEL APPROACHES FOR ESTIMATING GENETIC VARIANCES AND COVARIANCES

The limitations of methods for analysis of variance(ANOVA)in estimating genetic variances are discussed. Among the three methods(maximum likelihood ML, restricted maximum likelihood REML, and minimum norm quadratic unbiased estimation MINQUE)for mixed linear models, MINQUE method is presented with formulae for estimating variance components and covariances components and for predicting genetic effects. Several genetic models, which cannot be appropriately analyzed by ANOVA methods, are introduced in forms of mixed linear models. Genetic models with independent random effects can be analyzed by MINQUE(1)method whieh is a MINQUE method with all prior values setting 1. MINQUE(1)method can give unbiased estimation for variance components and covariance components, and linear unbiased prediction (LUP) for genetic effects. There are more complicate genetic models for plant seeds which involve correlated random effects. MINQUE(0/1)method, which is a MINQUE method with all prior covariances setting 0 and all prior variances setting 1, is suitable for estimating variance and covariance components in these models. Mixed model approaches have advantage over ANOVA methods for the capacity of analyzing unbalanced data and complicated models. Some problems about estimation and hypothesis test by MINQUE method are discussed.     

化学修饰提高胰岛素口服降血糖作用的研究

本文探索了用小分子化合物对胰岛素进行化学修饰,以增加口服降血糖的可能性.制备了乙酰胰岛素、琥珀酰胰岛素和半乳糖酰胰岛素.这些胰岛素不仅较好地保持了天然胰岛素的活性,而且其口服降血糖作用也较天然胰岛素明显增加,其中琥珀酰胰岛素是天然胰岛素的口服降血糖作用的二倍以上.这为口服或肛门给药的胰岛素新剂型的研制提供了科学依据.     

菌种与品种最佳组合的选育及增产效果

本文通过多年多点的田间接种试验,分析了大豆根瘤菌C_(33)(系VSDA_(110)的突变株)的增产效应.在合丰25号大豆接种C_(33)取得明显的增产效果,两年平均比CK增产28.55%,比61A76增产24.5%;C_(33)接种在其他品种以及在不同类型和肥力的土壤上增产效果也均高于CK和61A76,说明大豆根瘤菌C_(33)比当前生产上应用的61A76更具有广谱性和高效性.     

Benomyl Tolerance of Ten Fungi Antagonistic to Plant-parasitic Nematodes

Ten strains of fungi were tested for tolerance to the fungicide benomyl. Verticillium chlamydosporium strain 2 did not grow in the presence of benomyl; Drechraeria coniospora strains 1 and 2 and Chaetomium sp. tolerated only 0.1 μg benomyl/ml medium; Acremonium bacillisporum, an unidentified fungus, and Phoma chrysanthemicola uniformly grew at 1 μg/ml, but some hyphae grew at higher benomyl concentrations; Fusarium sp. tolerated 475 μg/ml, but some hyphae grew on medium amended with 1,000 μg/ml; Verticillium lecanii and V. chlamydosporium strain 1 routinely tolerated 1,000 μg/ml. Fungi generally grew more slowly at higher than at lower benomyl concentrations. Strains with elevated tolerance to benomyl were selected from Acremonium bacillisporum, Drechmeria coniospora, Fusarium sp., and an unidentified fungus. These strains retained the increased tolerance after repeated transfers on unamended medium.     

温度对圆尾肖蛸个体发育和繁殖力的影响

圆尾肖蛸(Tetragnotha vermiformis)在我国广泛分布于棉田、稻田、森林、果园。该蜘蛛具有捕食多种农作物害虫的能力,在湖堤、河岸、沟边更是蚊虫的有效天敌。本文仅就圆尾肖蛸的历期和繁殖力与温度的关系方面的试验结果进行了整理,并力图建立相应的数学模型,旨在为保护和利用工作提供科学依据。     

不同来源的肾综合征出血热病毒对Vero细胞的致病变作用

前文报道,肾综合征出血热病毒76-118株能使Vero细胞产生病变。本文报道76-118株和另11株不同来源的肾综合征出血热病毒(H537、A9、H5、R178、HB55、R22、Z10,沟3、L99、A16和J10)对Vero细胞的致病变作用(CPE )。其中除沟3株外,大部分毒株在感染Vero细胞后的第一代即可见明显的CPE。CPE的特点与76-118株相似,主要是感染细胞粘聚、融合,形成网状结构。CPE能被特异性抗HFRS病毒血清和型特异性单克隆抗体所中和抑制,但不能被特异性抗呼肠孤病毒Ⅲ型免疫血清所中和抑制。HFRS病毒对Vero细胞的致病变作用,对进一步研究HFRS病毒的某些生物学特性及实验方法等均有重要意义。     

脲酶抑制剂氢醌的环境效应评价

本文根据用标记和非标记氢醌进行的模拟、盆栽和田间定位试验,结合国内外文献有关氢醌的环境常数,论述了氢醌在土壤-植物系统的去向和代谢途径、对土壤酶活性的影响及其环境效应。得出的结论是:作为脲酶抑制剂使用的微量氢醌(0.3—0.4％,与尿素重量比),不会从土壤中淋失和挥发,在土壤和植物中没有累积,对与碳、氮和磷转化有关的土壤酶活性很少影响。在土壤中,它将通过氧化、臭氧化和生物学降解,经由环断裂生成二元酸或参与腐殖物质的合成。在植物体内,主要通过糖苷化得到同化和利用。因此,氢醌作为脲酶抑制剂在农业生产中应用是安全的。     

病毒唑及其与干扰素联合对慢性乙型肝炎抗病毒效应观察

本文报道了病毒唑及其与干扰素联合对23例慢乙肝近、远期抗病毒效应观察结果,并与12例未经抗病毒治疗的慢乙肝作对照(Ⅲ组),其中病毒唑与干扰素联合组(I组)12例,病毒唑组(Ⅱ组)11例。近期HBeAg、DNAP及HBV·DNA阴转率,I组分别为(41.6％、55.5％及28.s％,Ⅱ组45.4％、100％及33.3％,Ⅲ组8.3％、16.6％及8.3％。远期HBeAg及DNAP阴转率在I组分别为70％、83.7％。Ⅱ组60％、100％,Ⅲ组8.3％,50％。综合抗病毒效应,近期有效率在I、Ⅱ、Ⅲ组分别为50％、72.7％及16.6％。远期则分别为70％、55.5％及8.3％。无一例出现毒副反应。均完成疗程。上述结果提示病毒唑及其与干扰素联合对慢乙肝均有一定抗病毒效应,联合应用并不优于单一用药,但毒副反应也未见加重,而且病毒唑药源较方便,使用较安全,值得进一步研究。     

视黄酸和亚硒酸钠对肝癌细胞某些表型逆转的加和作用

 人肝癌细胞株SMMC-7721经1μmol/L视黄酸和或2.5μmol/L亚硒酸钠处理后,膜上纤维连接蛋白沉着量逐日上升,且较相应天数的对照组细胞增加,而甲胎蛋白分泌量和~3H-TdR参入率被明显抑制。视黄酸和亚硒酸钠同时处理的联合组作用强度接近于两者单独使用时作用强度的加和。对以上结果和视黄酸及亚硒酸钠使肝癌细胞接触抑制恢复及表型逆转的关系作了讨论。     

Bactericidal Activity of Catecholamine Copper Complexes

Washed or growing E. coli cells are killed by epinephrine, norepinephrine or dopamine in the presence of non lethal concentrations of Cu(II). Killing is enhanced by anoxia and by sublethal Concentrations of H₂O₁. The rate of killing is proportional to the rate of catecholamine oxidation. The copper epinephrine complex binds to E. coli cells, induces membrane damage and depletion of the cellular ATP pool. The cells may be partially protected by SOD or catalase but not by OH radical scavengers. Addition of H²O₂ to cells which were sensitized by preincubation with the epinephrine-copper complex, causes rapid killing and DNA degradation. Sensitized cells are not protected by BSA.