中国苦苣苔科的研究(七)

花萼钟状,5裂达基部;裂片条形。花冠白色或淡紫色(?);筒近筒形或漏斗状筒形;檐部二唇形,比简短,上唇正三角形或近半圆形,不分裂,下唇3浅裂。能育雄蕊2,位于下侧方,伸出;花丝着生于花冠简近中部或稍超过中部处,狭条形,直,有1脉;花药基着,宽卵形或长圆形,在腹面顶端连着或分离,药室平行,顶端不汇通。退化雄蕊或存在,3,位于上方,小,或不存在。花盘低杯状。雌蕊内藏;子房条形,2侧膜胎座不内伸,2裂,裂片极叉开,生有胚珠;花柱比子房短,柱头小,扁头状,与花柱等宽或比花柱稍     

Immobilization of fumarase by entrapment of rat liver mitochondria in polyacrylamide gel using gamma rays

A stable immobilized preparation of fumarase (EC 4.2.1.2) was obtained by entrapment of rat liver mitochondria in acrylamide polymerized by using gamma irradiation (100 kR). The enhanced stability and the efficiency of the entrapped enzyme have shown potential for repeated use for the production of L-malic acid from fumaric acid. The possible formation of succinic acid in the system could be controlled by incorporating malonate along with detergents such as sodium deoxycholate or sodium dodecylsulfate in the reactor system.     

Mode of uptake of insoluble solid substrates by microorganisms. II: Uptake of solid n-alkanes by yeast and bacterial species

Using two species of yeast and one of bacterium, evidence has ben obtained which indicates that the microbial uptake of solid alkane powders occurs primarily through a substrate solubilization mechanism. EDTA, a strong inhibitor of hydrocarbon solubilization by the cells, inhibited the growth of these organisms on alkane powder; the inhibition could be removed vai a supply of artificially solubilized alkane. One of the yeast strians, which was a mutant incapable of growing on solid alkane powder and liquid alkane, could grow very well on artifically solubilized alkanes. It was demonstrated that the solid alkane solubilization rate during microbial growth could satisfactorily account for the maximal alkane uptake rate actully observed during growth. The specificity of solubilization for the solid alkane used as the growth substrate was demonstrated.     

四川阿坝藏族自治州牧场裸头科绦虫及其自然传播媒介地螨的调查研究

我国草原牧区裸头科绦虫没有系统的研究报告,阿坝藏族自治州位于四川西北高原,是四川省的重要牧区。主要牲畜为牦牛、绵羊和马等,又是该省重要的军马基地。由于牲畜普遍流行绦虫病,使畜牧业生产受到严重损害。草原研究所(1979)报告,莫氏绦虫     

利用细菌脱除金、锡和铜精矿中砷的研究

本文报道用从毒砂矿酸性水中分离得到的氧化毒砂和对砷毒害耐受力高的氧化亚铁硫杆菌(Thiobacillus ferrooxidans)C-3菌株,进行浸出砷的试验结果。以毒砂矿物形态存在的砷,主要是在细菌直接氧化下溶出的。影响细菌浸出砷的因素较多,其中精矿含砷量的高低是关键因素。含砷量为11.94％的金精矿,当矿浆浓度为10％时,采用两次浸出,砷的脱除率仍可达70％以上。     

Investigation of huge negative circular dichroism spectra of some nucleoproteins

Under certain conditions of preparation, DNA, whether free or complexed with polylysine or histone KAP (I, fl), produce huge negative circular dichroism (CD) spectra with maxima at about 270nm. In order to investigate the cause of these spectra, reconstituted polylysine-DNA complex was used as a model system. It was found that the CD change of DNA in the complex is not a linear function of the fraction of base pairs bound. Such a CD spectrum is not changed despite dilution up to 128 folds for as long as 12 hours. Difference CD spectra taken between free DNA and any of the complexes are qualitatively the same, and are similar to those of free DNA and nucleohistone KAP (Fasman et al., Biochemistry 9, 2814-2822, 1970), free DNA and direct mixed polylysine-DNA complexes, or free DNA in high salt (Chang et al., Biochemistry12, 3028-3032, 1973). The suggestion is made that this CD spectrum might be caused by specific conformational changes in DNA, perhaps belonging to the family of B to C transitions followed by a further structural distortion of DNA due to aggregation of the nucleoprotein molecules.     

南昌西山洗药湖泥炭的孢粉分析

南昌西山泥炭沼泽分布甚为广泛。是我国南方较为典型的泥炭沼泽之一。我们进行了三个钻孔的泥炭孢粉分析,找到种类众多的孢粉,孢粉组合中以松属(Pinus)和栲属(Castanopsis)花粉占优势,枫香属(Liquidambar〕、桤木属(Alnus)、柃木属(Eurya)、柳属(Salix)、冬青属(Ilex)、栎属(Quercus)、杨梅属(Myrica)、乌桕属(Sapium)、杉木属(Cunninghamia)等也有相当数量。草本花粉和孢子在组合中属于次要地位,草本花粉以禾本科(Gramineae)、菊科(Compositae)为主,水生植物花粉也有一定的数量。孢子是以蕨属(Pteridium) 和水龙骨科(polypodiaceae)占多数。孢粉组合反映常绿阔叶-常绿针叶和杂有少数阔叶落叶的混交林。洗药湖泥炭的孢粉分析,清楚地反映了全新世时期西山地区森林发展史具有四个阶段:第一阶段以栲属为主的森林,第二阶段以松属为主的森林,第三阶段以桤术属和松属为主的混交林,第四阶段混有栲属、栎属的松树混交林。从森林演替的历史看出,西山泥炭沼泽的形成开始于全新世的大西洋期。     

Ribonucleic Acid and protein synthesis in chick embryo cells infected with fowl plague virus

Fowl plague virus comprised four major protein components and several minor ones, two strains of the virus giving similar results. One of the components was identified as the nucleocapsid protein. Synthesis of the virion proteins could readily be detected in infected cells 3 hr after infection. The two subcellular fractions associated with viral ribonucleic acid (RNA) polymerase activity (nuclei and ribosomal pellet) were associated with the protein of the nucleocapsid and a second virion protein of unidentified function. Measurement of viral RNA and protein synthesis in cells infected with preparations of ultraviolet irradiated virus showed that the capacity to synthesise the RNA and protein species of highest molecular weight was lost most quickly, suggesting that the pieces of viral RNA function independently.