甘蔗幼叶切段培养中的体细胞胚胎发生

本文从形态学和组织学方面研究了甘蔗幼叶胚性愈伤组织发生及体细胞胚胎的形成过程。甘蔗幼叶片切段培养于含2.4—D1.5mg/1的MS培养基上,4—6天后切段开始形成愈伤组织,约10天后愈伤组织表面出现白色颗粒状结构。将含有白色颗粒状结构的愈伤组织转移至不含激素的培养基中,7—10天后可见有小植株长出。组织学和形态学观察表明,甘蔗离体再生植株是通过体细胞胚胎发生途径。     

高原低氧对喜马拉雅旱獭、高原鼠兔、缺氧敏感大鼠颈动脉体超微结构的影响

应用扫描电镜结合透射电镜技术,对上海(海拔10米)的大鼠,5天内从上海急进到海拔3300米的大鼠,由北京引入西宁的子4代大鼠,同高原的喜马拉雅旱獭和高原鼠兔的颈动脉体微细结构进行对比观察。结果表明,高原低氧环境使由低海拔急进到高海拔的大鼠颈动脉体Ⅰ型细胞增生、肿胀、体积增大,胞浆中致密核心囊泡数量减少,线粒体变性肿胀,神经末稍中突触囊泡减少,Ⅰ型细胞表面微绒毛变性脱落;而喜马拉雅旱獭和高原鼠兔对高原低氧环境有较好的适应,未见缺氧损害征象。     

钐在小鼠肝脏细胞中的动态观察

It is generally considered that the rare earth compounds are plasma membrane-impermeable, thus affecting the cells only on their surface. Recently, we found that after repeated injections to mice of large dose of samarium trichloride, a soluble compound of rare earth, samarium aggregates appeared in Kupffer cells and hepatocytes of liver. In this study, we aimed at observing the route by which samarium enters the liver cells and the process of the formation of samarium aggregates. Samarium trichloride was given to Swiss mice at one dose of 70 mg/kg intravenously. Thereafter, at different intervals from 15 min to 48 h after the injection, the samarium in liver was traced dynamically by electron microscopy and X ray microanalysis. From 15 min to 2 h both Kupffer cells and hepatocytes endocytosed samarium-containing particles and formed phagosomes, in which the ingested particles were progressively concentrated. Besides, the small phagosomes fused with each other. Phagocytosis was especially active in Kupffer cells. During the 4 h to 24 h many Kupffer cells were degenerated and broken. In hepatocytes the phagosomes gathered mostly around the bile canaliculi. Groups of highly electron-dense particles were found in the lumen of bile canaliculi, implying the excretion of samarium by bile. At the 48 h, the samarium-containing phagosomies were found still in both kinds of cells in the liver.     

几种哺乳动物精子顶体膜囊泡形成的研究

在猪、绵羊、地鼠这几种哺乳动物的精子体外获能后,在顶体反应的超显微结构中观察到:精子顶体膜囊泡化呈现多种形态,但囊泡都是由精子顶体的双层外膜多位点自我融合而形成的,质膜并不参与囊泡化,这一结果与前人报道的不同。     

滑菇营养生理研究

本文研究了滑菇在木屑-麦麸基质上生长期间,菌体对基质的转化效率和基质中主要组分的降解规律。实验结果表明:子实体绝对生物学效率为12.43%,产量系数为16.94%。子实体阶段的木素、半纤维素和纤维素的降解量以及非木质纤维素组分的减少量占子实体阶段基物中干物质减少量的百分比值分别为:5.85、17.54、49.13和27.48%。由此可见,纤维素是子实体生长阶段的主要碳源。滑菇在菌丝生长和子实体生长阶段分别有纤维素酶和半纤维素酶的活性高峰出现。进一步证明了:子实体阶段这两种酶的活性增加与子实体形成有密切关系     

合掌消的甾体成分

合掌消(Cynanchum amplexicaule)系萝藦科(Asclepiadaceae)鹅绒藤属植物。该植物全株药用,民间用于治疗风湿性关节炎,其化学成分未见报道。由于其形态特征与中药白薇极为相似,很多地方混用作白薇或其代用品。我们曾报道了白薇中的C_(21)甾体甙类成分,本文报道合掌消的化学成分。     

黑龙江桔梗科叶表皮研究

本文对分布在黑龙江省的桔梗料(Campanulaceae)植物叶表皮进行了光学显微镜和扫描电镜方面的观察。发现桔梗科植物的气孔复合体是不规则型的;毛状体是单细胞的,其表面的角质纹饰因类群而异;表皮角质纹饰可用于某些种间的鉴别。     

Mg~(2+)加强嵌有H~+-ATP酶脂酶体脂质分子的堆积(packing)

用亲脂性的灵敏的荧光MC 540标记在有Mg~(2+)(1mM)与无Mg~(2+)条件下重建的线粒体H~+-ATP酶脂酶体,后者的荧光强度较前者增加30%左右.这提示,含Mg~(2+)的脂酶体的脂质分子间的堆积紧密度增加.在N-AF系列(n=27和16)探剂与MC 540之间的能量转移效率,又以反应靠近脂双层表面变化的2-AP与MC 54O之间最高.这进一步表明,含Mg~(2+)的脂酶体具有较适合流动性是与Mg~(2+)通过调节靠近脂双层表面的脂质分子具有适度的堆积相关的.这对阐明我们已提出的Mg~(2+)促进线粒体H~+-ATP酶重建作用模型进一步提供了较直接的证据.