我国某些蔷薇属花卉的核型研究

本文报道了我国产的5种和14个品种的蔷薇属花卉的染色体数目和核型,结果如下:小花型为二倍体,2n=2x=14,少数为混倍体;中花型为三倍体,2n=3x=21;大花型为四倍体,2n=4x=28。大部分种的核型均由其中部和近中部着丝点染色体组成,少数种具近端着丝点染色体。它们可以区分为3种核型类型,即1A、2A和1B。     

中国长角圆属一新种

长角圆属Temeritas属弹尾目圆科 ,其触角特别长,第四节分很多亚节,无胫跗感毛。分布于中美、南美、南非、马达加斯加、印度、越南、澳大利亚及新西兰。中国原无记载。作者1982年访问西北农学院,承周尧教授给予研究的机会。中华长角圆(虫姚)Temeritas sinensis新种 体长1.5—1.9毫米。其与同属科类的区别为触角较短(图1);第三节近端部有2小感觉杆,生在2凹陷内;第四节分26亚节,各亚节有1圈长毛。背毛为长刺状,混有一些小毛(图2)。后足转节外侧有5长毛,内侧1长毛(图9)。握弹器有3端毛(图13)。弹尾长(图12):弹器基有7—7毛;齿节约有40毛;端节内、外缘齿状,内缘有15小齿,有1端节毛。生殖节毛列如图13,雌一尖而弯曲的尾器。     

马立克氏病毒单克隆抗体的研究

获得了4株分泌马立克氏病毒(MDV)特异性单克隆抗体(McAb)的杂交瘤细胞:4BS10对MDV所有毒株呈阳性反应;4CN8 对MDV血清1,3型毒株发生反应;2BN90和4CN24只对MDV血清1型毒株有阳性反应。3个McAb属IgG1,1个为IgG2b,均不中和MDV,免疫扩散试验也无沉淀线。对禽白血病毒(ALV)无交叉反应。 以2BN90和辣根过氧化物酶、异硫氰酸荧光素的结合物进行直接酶联免疫吸附试验和直接荧光抗体试验,均获得成功。抗体滴度前者为1/51,200,后者为1/640。对ALV无交叉反应。     

板栗枝插生根试验

促使枝插生根是板栗营养繁殖最有希望的方法之一,因其方法简便,同时又解决了由于板栗嫁接时常遇到的砧穗不亲和的问题。 试材为‘AU—Cropper’、‘AU—Homestead’和‘AU—Leader’三个板栗品种。插条采自植株成熟部位经修剪诱发的健壮副梢上抽生的春梢,剪取其顶部和基部枝条,长15—20厘米;此外,从植株未修剪的成熟部位,剪取当年生春梢(带有2—3厘米长的去年生枝)。插条上的叶片,仅留顶部2—3片,余者剪除,然后在近轴末端的     

Cytogenetic Mapping of Enzyme Loci on Chromosomes J and U of DROSOPHILA SUBOBSCURA

Enzyme loci located on chromosome J and U were mapped cytologically by means of a Y translocation technique. A linkage map of the two chromosomes was established in a parallel experiment and the recombination frequency in different regions of the chromosomes determined. A comparison of the cytogenetic localization of the enzyme genes in D. subobscura and D. melanogaster indicates that many paracentric inversions must have taken place in the course of divergent evolution. However, no displacements of genes from one element to another due to pericentric inversions, reciprocal translocations or transposing elements can be observed. In spite of the large number of structural rearrangements that have occurred in the phylogeny of the genus Drosophila, gross similarities of banding pattern in homologous regions of the chromosomes of the two species become apparent.     

An adaptive control algorithm for fed-batch culture

The implementation of adaptive control for a fed-batch culture in order to maximize the output of product based on a self-adjusting model is discussed in the present work. Optimization methods were applied to the generalized mathematical model of a fed-batch fermentation process to determine control algorithms that could be used for on-line process control. The efficiency of the proposed adaptive algorithms was investigated by simulating a model system. The model of amylotytic enzyme fermentation that was proposed by the authors was taken from a real process. Dynamic modelling has shown that the main problem of realization is connected with the on-line identification of the adaptive model's parameters. To avoid this problem, we have introduced special limitations on the parameters' time variations that increased the convergence of the identification algorithm. The results of the investigation have shown the efficiency of the proposed adaptive algorithms, and the results of this work should be investigated for real process control.     

管花马兜铃化学成分的研究

从管花马兜铃中分得马兜铃酸-A,7-甲氧基马兜铃酸-A,马兜铃内酰胺-β-D-葡萄糖甙,尿囊素和Eupomatenoid-7。     

银杏科研的主要成就和展望

前言银杏又名白果,是现存种子植物中最古老的孑遗植物,也是源于我国的特有珍贵树种。学者们一向把它视为植物界的奇珍,在植物分类学、树木学、果树栽培学和古植物学上占有特殊的位置,至今国内外植物学家、地质学家,以及果树栽培学家们,仍对它进行着深入细致的研究。银杏的科学奥秘将逐步被揭开。     

大豆根瘤侵染细胞中一种细胞质内含物的电镜观察

在中国丰收11号大豆根瘤侵染细胞中,我们发现了一种电子密度很高,体积很大,形状为圆形或近似圆形,外面没有界膜,常位于胞间隙附近的特殊的细胞质内含物。高尔基体及其小泡,丰富的粗糙型内质网和核糖体常在它的附近,其中一些核糖体正沉积在它的表面。它主要是由核糖体凝聚而成,高尔基体和内质网在它的形成中也起了一定作用。它的内部含有颗粒状,纤维状,泡状和管状物质。它的出现似乎与侵染细胞固氮有关。     

甲型肝炎病毒对理化因子的稳定性

用放射免疫成斑法研究了甲型肝炎病毒FM-175株的理化稳定性和灭活条件,证明甲型肝炎病毒理化稳定性与其它肠道病毒相似,具有广范围的pH(2～10)稳定性;Mg~(++)和Ca可增强其热稳定性,不能抵抗冷冻干燥,但对热的抵抗力明显高于普通肠道病毒,可被紫外线迅速杀灭,也可被多种消毒剂如3～8％的甲醛液,50～90％的乙醇,2％的石炭酸及400ppm的有效氯等杀灭,但可抵抗0.1％甲醛液,2～5％的来苏儿及200ppm的有效氯1小时以上,本研究工作为甲型肝炎病毒的理化性状、保存及消毒条件等提供了实验数据。