朝鲜蓟的研究进展

朝鲜蓟具有很高的营养、药用和观赏价值,富含维生素、蛋白质、铁、磷、钙等多种营养成分和菜蓟酸、天门冬酰胺等化合物,其生物活性逐渐受到人们的关注.该文对朝鲜蓟的化学成分和生物活性的研究进展进行了综述,为进一步开发利用提供依据.     

Further Studies in Magnetotropism

Studies have been mode of the growth curvatures induced in theroots of Lepidium sativum, the coleoptiles of Avena saliva andthe sporangiophores of Phycomyces blakesleeanus by exposureto an intense magnetic gradient during continuous rotation ona slow klinostat (0.5 rpm). Attempts have been made to determinethe relationships of the curvature responses to the parametersof the magnetic field (H, dH/dx, and H. dH/dx). Analysis ofthe data was by a progressive regression analysis up to thethird order coupled with an analysis of variance to test theimprovement of fit at each stage. Response is characterizedby an initial lag (reaction time, T) followed by a constantrate of curvature down the magnetic gradient for the first 20or 30? of curvature. The reciprocal of T was the most satisfactorymeasure of response (i. e. a measure of the rate of inductionof the response while the organ was in a constant magnetic environment)and in Avena and Phycomyces was best fitted by linear regressionson log_edH/dx and on log_eH. dH/dx. For Lepidium, with much morevariable data, the best fit was with a linear regression onlog_eH. The significance of these results is discussed.     

SA脂质体介导DNA转染细胞的进一步研究

ＳＡ脂质体可高效介导ＤＮＡ转染ＣＶ－１细胞,本文进步研究表明,ＳＡ脂质体还可介导ＤＮＡ高效瞬时和稳定地转染ＣＨＯ和ＣＯＳ细胞。ＳＡ脂质体和ＤＮＡ形成复合物可保护ＤＡＮ不被核酸内切酶和ＤＮａｓｅＩ降解。荧光标记和细胞松驰素Ｂ抑制实验分别表明,ＳＡ脂质体易被细胞吸附,主要通过内吞传送ＤＮＡ进入细胞,而Ｌｉｐｏｆｅｃｔｉｎ主要通过融合传送ＤＮＡ进细胞。     

水杉的未尽事宜

主要阐述与水杉有关的三个问题: 首先是水杉研究的教训, 特别是从编辑、作者和学者的角度; 其次讨论水杉研究的不明之处, 包括王战的标本是如何到达吴仲伦之手而转送给郑万钧的, 薛纪如和华敬灿谁先打听到小河的原产地, 三木茂的论文是如何到达中国而胡先骕又是如何得到的; 并讨论了水杉的栽培及栽培品种的注册以及水杉原产地的资源保护、旅游开发及宣传; 最后建议成立水杉博物馆, 编写中国植物采集史, 编写东亚植物分类学文献目录新续编。     

四氯合铂酸钾(K_2PtCl_4)与细胞色素c(Cyt·c)修饰体系的进一步研究

从K_2PtCl_4与Cyt·c反应产物中分离得四个组分,SDS-PAGE及元素分析测定结果表明,它们分别对应于Cyt·c寡聚体、三聚体、二聚体及单体。这揭示了K_2PtCl_4对Cyt·c存在多位点修饰,南非如Kostic报道的Met-65为其唯一修饰位点。通过K_2PtCl_4与羧甲基化Cyt·c修饰产物的分析研究,证实了另一标记位点His-33的存在。对Cyt·c二聚体衍生物的还原电位、紫外一可見及红外光谱研究表明,Cyt·c血红素周围的电子环境仍保持完整,但其二级结构有较大的扰动。