颜延之诗文特点及其成因的探讨

颜延之是南朝文风演变的一个重要环节。颜延之诗文具有题材和风格的多样性的特点。颜延之的诗文及其表述的特点可以在他所处的社会环境、文学环境、生活经历、思想性格、文学修养中找到答案。     

从壮语和泰语的亲属称谓看壮、泰两族的婚姻形态

运用社会语言学和文化语言学的理论和方法,对壮语和泰语的亲属称谓进行比较,探索壮、泰两族曾经经历的婚姻形态及其演变情况。     

竞争反应原理研究金属离子与硫胺素的络合作用

本文根据竞争反应原理、应用离子选择电极方法、研究镉(Ⅰ)、锌(Ⅱ)离子与硫胺素的成络作用。并测定了稳定常数值     

Gamete formation reflects the sexual pheromone hierarchy ofDictyostelium giganteum

Summary Sexual development inDictyostelium giganteum begins with the appearance of small, amoeboid gametes that fuse to produce mainly binucleate cells which differentiate into zygote giant cells. The data presented here show that the number of gametes produced by each strain (WS589>WS606>WS607>WS588) is directly related to its position in this hierarchy.This work was supported by a grant (A6807) from the Natural Sciences and Engineering Research Council of Canada.     

Biological effects of trilostane in vitro on oocyte maturation and fertilization in the hamster

Summary The effects of the inhibition of steroidogenesis by trilostane on oocyte maturation were examined by studying spontaneous maturation and fertilization in vitro. 10^–6 M trilostane had no influence on the meiotic process, whether the oocytes were naked or not. At a concentration of 10^–6 M and 10^–7 M trilostane, low normal pronuclear formation and high polyspermy were found during in vitro fertilization. However, no retarded male pronuclear development could be detected in the trilostane-treated group. Thus, steroid producing activity within ova is apparently necessary to prevent multiple sperm penetration, but it has no effect on meiosis or the action of the so-called male pronucleus growth factor (MPGF).     

模糊综合评判优选长春花细胞分化条件

研究不级其浓度配比对长春花细胞分化的影响；利用综合评判方法优选不同培养目的培养条件。为开发利用该过程提供理论准备。     

SD－5菌株原生质体形成与再生条件的研究

探讨了培养基成分、培养时间、高渗缓冲液成分和ｐＨ、溶菌酶浓度以及酶解温度和时间对苏云金杆菌ＳＤ—５菌株原生质体形成和再生的影响；结果表明，ＳＤ—５菌株原生质体形成和再生的最佳条件组合为：ＰＢＧ培养基、３０℃培养１４ｈ再活化５ｈ，以ＳＭＭｐＨ６．５作酶解缓冲液，溶菌酶浓度０．６ｍｇ／ｍｌ，３４℃处理６０ｍｉｎ．     

Impulse propagation from the SA-node to the ventricles

Summary Normally the pacemaker of the mammalian heart is located in the sinus node. In the rabbit the sinus node can be subdivided into two regions, the center of the node where the impulse originates and the border zone through which the impulse is conducted towards the atrium. Conduction properties of both regions were investigated. It appeared that conduction velocity increases and refractoriness decreases when one goes from the nodal center towards the atrium. The tissue mass of the atrium is large in comparison to the sinus node and normally the resting membrane potential of atrial fibers is more negative than that of nodal fibers; consequently, a potential difference exists causing a current flow between both areas. Evidently this hyperpolarizing current flow depresses impulse formation in the border zone fibers which have better intrinsic pacemaker properties than fibers in the nodal center. If the impulse has reached the atrium it is conducted with a relatively high safety factor and will reach the AV node in principle without difficulty. The AV node, if deprived of sinus nodal dominance, develops spontaneous activity originating from the lower nodal fibers. Also in this structure, electrotonic depression by surrounding tissue causes deceleration of the pacemaker.     

碳酸盐建造天然储层及其在地质历史中的演化

流体分布特征及其在储层中的运移取决于岩石的储集性和层序内部结构。块状储层一般是礁或浮游生物建造,部分属地台底栖生物建造,其中流体可进行垂向和横向运移;层状储层是典型的底栖生物建造,具不同渗透性的岩层成互层状,以横向运移为主;岩性圈闭储层产于未补偿拗陷的沥青质-硅质、粘土-碳酸盐建造。层状储层遍及整个显生宙,但其相型、孔隙空间的组成及特征均有所改变。礁块储层的意义在地质历史中随其厚度及非均质性的增加均有所增长。在中生代末的浮游生物建造中常有块状储层。岩性圈闭储层自泥盆纪以来零星出现于较年轻的沉积中。