腥黑粉菌属一新种

本文报道了从意大利进口兔尾草(Lagurus ovatus L.)上截获的腥黑粉菌属一新种——兔尾草腥黑粉菌(Tilletia laguri G.M.Zhang,G.X.Lin & J.R.Deng),同时讨论了该种与近似种的区别,文中对其形态特征有拉丁文和汉文描述,并附有图片。主模式标本保存在深圳动植物检疫局真菌标本室,等模式标本分别保存在德国蒂宾根大学范基黑粉菌标本馆(HUV)、中国科学院微生物研究所真菌标本室和华南农业大学植保系真菌标本室。     

Further Evidence for Multiple Forms of an N-Methyl-d-Aspartate Recognition Domain in Rat Brain Using Membrane Binding Techniques

Abstract— Pretreatment with sulfhydryl-reactive agents, such as N-ethylmaleimide and p-chloromercuriphenylsul-fonic acid, invariably resulted in marked inhibition of the binding of dl -(E)-2-amino-4-[³H]propyl-5-phosphono-3-pentenoic acid ([³H]CGP 39653), a competitive antagonist at an N-methyl-d -aspartate (NMDA)-sensitive subclass of central excitatory amino acid receptors, in brain synaptic membranes extensively washed and treated with Triton X-100, but did not significantly affect the binding of L-[³H]-glutamic acid ([³H]Glu), an endogenous agonist. The pre-treatment was effective in reducing the binding of [³H]-CGP 39653 at equilibrium, without altering the initial association rate, and decreased the affinity for the ligand. Pretreatment with sulfhydryl-reactive agents also enhanced the potencies of NMDA agonists to displace [³H]-CGP 39653 binding and attenuated those of NMDA antagonists, but had little effect on the potencies of the agonists and antagonists to displace [³H]Glu binding. The binding of both [³H]CGP 39653 and [³H]Glu was similarly sensitive to pretreatment with four different proteases in Tritontreated membranes, whereas pretreatment with phospho-lipase A₂ or C markedly inhibited [³H]CGP 39653 binding without altering [³H]Glu binding. Moreover, both phospho-lipases not only induced enhancement of the abilities of NMDA agonists to displace the binding of [³H]CGP 39653 and [³H]Glu, but also caused diminution of those of NMDA antagonists. These results suggest that both sulfhydryl-reactive agents and phospholipases may predominantly interfere with radiolabeling of the NMDA recognition domain in a state favorable to an antagonist by [³H]CGP 39653, with concomitant facilitation of that in an agonist-preferring form by [³H]Glu. The possible presence of multiple forms of the NMDA recognition domain is further supported by these data.     

邻二氮菲－Fe2＋氧化法检测H2O2／Fe2＋产生的羟自由基

报告检测H₂O₂/Fe^2＋所产生羟自由基的新方法. 羟自由基氧化反应后, 邻二氮菲-Fe^2＋的A₅₃₆明显下降, 且△A₅₃₆与邻二氮菲, FeSO₄及H₂O₂呈量效关系, 随反应时间延长, △A₅₃₆依幂函数规律上升. 此法试验结果表明, 甘露醇, 抗坏血酸及硫肥清除羟自由基作用呈明显的量效关系.     

中国种子植物区系定量化研究 V．区系相似性

本文总结了应用相似系数即关联系数进行植物区系相似性分析的现状,指出了存在的问题．然后,从集合论角度讨论了区系相似性、相似关系及其相似系数的实质．作者以为在区系相似性分析中应用Ｒ．Ｒ．Ｓｏｋａｌ和Ｃ．Ｄ．Ｍｉｃｈｅｎｅｒ（１９５８）提出的简单匹配系数比较适宜,同时亦能避免以往区系相似性分析中缺乏可比性及某些“表相”相似等问题．最后,还提出了总体相似系数和类型相似系数二个新概念,以便按照吴征镒教授关于中国植物区系研究的学术思想统一研究各个不同地区植物区系的相似性．对此,作者用了６个区系实例进行了演算说明．     

EB病毒转化Hu－TLC－SCID小鼠脾细胞的实验研究

利用ＥＢ病毒转化可产生较高水平人ＩｇＧ和特异性抗２型登革病毒人抗体的Ｈｕ－ＴＬＣ－ＳＣＩＤ小鼠脾细胞,通过免疫组化、免疫荧光和ＰＣＲ法检测转化细胞的人Ｂ细胞表面标志、ＥＢ病毒抗原和ＥＢ病毒基因。结果表明,被转化的Ｈｕ－ＴＬＣ－ＳＣＩＤ小鼠脾细胞能继续产生抗２型登革病毒的特异性人抗体,并具有人Ｂ细胞的、ＳｍＩｇＧ标志及ＥＢ病毒潜伏膜蛋白－１（ＬＭＰ－１）基因,可表达ＬＭＰ－１和ＥＢ病毒核抗原（ＥＢＮＡ）。     

Isolation and preliminary characterization of gas1-1, a mutation causing partial suppression of the phenotype conferred by the gibberellin-insensitive (gai) mutation in Arabidopsis thaliana (L.) Heyhn

The semi-dominant gai mutation of arabidopsis confers a dark-green dwarf phenotype resembling that of gibberellin (GA)-deficient mutants. In contrast to GA-deficient mutants, gai mutants do not respond to GA treatments and accumulate higher levels of bioactive GAs than are found in wild-type controls. The gai mutation thus alters the responses of plant cells to GA, indicating that the GAI (wild-type) gene product is involved in GA reception and/or signal transduction. Here we describe the isolation and preliminary characterization of a mutation, gas1-1, which is not linked to gai and which partially suppresses the effect of the gai mutation. Double mutant, gai gas1-1, homozygotes are less severely dwarfed and lighter green than gai GAS1 controls. However, comparisons of the effects of treatments with exogenous GA demonstrate that gas1-1 does not increase the GA responsiveness of the gai mutant. Thus the gas1-1 mutation appears to reduce the GA-dependency of plant growth, and identifies a gene (GAS1) whose product is a candidate GA signal-transduction component.Abbreviations GA gibberellin - GA₃ gibberellic acid We thank Maarten Koornneef (Wageningen Agricultural University, The Netherlands) for providing mutant seed stocks; Mark Aarts and Bernard Mulligan (University of Nottingham, UK) for performing the -irradiation. This work was made possible by AFRC/BBSRC PMB Grants PG208/520 and PG208/0600, and by a grant from the Gatsby Charitable Foundation. P.C. was supported by a Human Capital and Mobility Fellowship from the EC.     

原生质体电融合酵母多倍体生理特性的研究

对原生质体电融合技术获得的11株酵母多倍体融合株,进行了一系列生理特性的分析比较．结果发现,在电融合过程中,融合株的细胞体积及DNA含量并不随着核倍性呈线性递增．而是有其特殊的变化规律。当糖化酵母sta1、sta2和sta3在细胞核中各自纯合时,明显表现出表达的剂量效应。其中sta1、sta2纯合的融合株．在YEPS培养中,GA分泌可被淀粉大量诱导,表现出一定的二次生长特性。从分析结果推测,在亲株5301-14D及HU-TY—1A中可能有对GA分泌不利的因素。