Scanning electron microscope study of early lichen synthesis

In the early stages of cellular interaction between the symbionts of Lecidea albocaerulescens, the phycobiont produced an extracellular sheath which bound to it hyphae of the mycobiont. Such a sheath may be a means by which the symbionts recognize each other. Hyphae of the mycobiont formed flattened appressoria as they grew over the algal cells and in this way secured the autotrophic population necessary for the development of a lichen thallus.     

Light and electron microscope study of cell walls of brown and red algae

A survey of the structure of the cell walls of green, brown, and red algae, as seen under light and electron microscopes is in progress. In this report a comparison of the cell wall structure of a brown alga, Dictyota flabellata, and a red alga, Helminthocladia californica, is presented. In Dictyota, typicalofthe brown algae, the microfibrillar pattern in the apical cells and in the adjacent cells of the thallus tip is reticulate. In mature cells the microfibrils are dominantly parallel in orientation. Pits, fields ofclosely set pores, are distinctive. The microfibrils in the pit areas are masked by nonfibrillar material. Helminthocladia, with a cell wall characteristic of the red algae, differs from Dictyota in that the microfibrillar pattern is reticulate throughout the thallus. In the pit areas the microfibrils are not masked by amorphous material.     

Scanning electron microscope: potentials in the morphology of microorganisms

Morphologic characteristics related to ecology and evolutionary sequences, and to specific, generic, and familial relations, can now be determined with the scanning electron microscope. These detailed characteristics will help to establish a more natural faunal classification and will enable more accurate ecologic and biostratigraphic correlations.     

Nucleoside incorporation into strain L cells: inhibition by pleuropneumonia-like organisms

Contamination of Strain L cell cultures by pleuropneumonia-like organismtis (PPLO) resulted in a complete inhibition of the incorporation of tritiated thymnidine and uridine. Contanminated cultures were characterized by a concentration of PPLO along the margins of the cells and in the intercellular-spaces of the cultures. Autoracliograins of PPLO-contaminated cultures were characterized by exposed silver grains over the margins of the cells. Kanamnycin was efjective in the elimination of PPLO and the restoration of nucleoside incorporation.     

香稻胚乳的垩白性状研究及扫描电镜观察

【目的】研究不同香稻品种垩白性状与胚乳细胞和淀粉粒的形状结构、排列方式及发育情况的关系,为进一步研究香稻垩白性状的形成机理及培育优良品质的香稻新品种打下基础。【方法】通过田间试验,调查11个香稻品种的垩白粒率、垩白面积和垩白度,并对香稻品种胚乳细胞及淀粉粒进行电镜观察。【结果】供试11个香稻品种间差异最明显的垩白性状为垩白粒率,其次是垩白面积,最小的是垩白度,垩白粒率和垩白度成正比,垩白粒率越高则垩白度越高。不同香稻品种稻米胚乳细胞的排列方式、形态及其横断面淀粉粒的分布存在明显差异,其与垩白性状的形成存在一定关联,根据稻米胚乳中垩白形成的位置不同,可将垩白性状分为腹白、心白和背白3种垩白亚类。同一香稻品种,垩白米与无垩白米在淀粉粒形状结构及排列方式等方面也存在明显差异,但垩白米的透明部位和无垩白米的淀粉粒间无明显差异,且垩白度低的部位淀粉粒发育良好。【结论】香稻稻米的垩白性状与胚乳细胞和淀粉粒的形状结构、排列方式及发育情况密切相关,可用于香稻稻米品质鉴定。     

Neuron geometry and circuitry via the electron microscope: intracellular staining with osmiophilic polymer

Intracellularly injected cobalt catalyzes the generation of an osmiumbinding polymer from 3,3'-diaminobenzidine in neurons of Aplysia californica. Excellent structural preservation of nervous tissue is coupled with easy recognition of fine branches of the injected neurons in the electron microscope. This permits detailed structural analysis of synaptology.     

Nerve endings: rapid appearance of labeled protein shown by electron microscope radioautography

Electron microscope radioautographs of nerve ending fractions from mouse cerebrum show that radioactive protein is associated with nerve endings 15 and 90 minutes after intracerebral injection of tritiated leucine and lysine. The results are consistent with synthesis of protein at nerve endings, or with extremely rapid transport of particulate protein to nerve endings in the mouse cerebrum, or both.     

红江橙嵌合特点的扫描电镜观察

以嫁接嵌合体红江橙为材料，在扫描电镜上观察了红江橙及其分离出来的４种变异类型的叶、果表面及其切面的结构．结果表明，红江橙的叶面与其分离出来的黄肉果和橘变果有较大差异，红江橙果皮切面海绵层介于黄肉果与橘变果之间，而从果皮的切面发现表皮层的细胞排列紧密，体积较小，呈长形方格状，与紧接其下的海绵层具有较大的、圆形蜂窝状的细胞明显可分．作为同质体的黄肉果和橘变果，则未能观察到这种结构差异     

盲蝽卵的扫描电镜观察研究(I)(半翅目:盲蝽科)

记述了植食性盲蝽肉桂泡盾盲蝽PseudodoniellachinensisZheng、八角泡盾盲蝽Pseudodoniellatypica(China&Carvalho)、苜蓿盲蝽Adephocorislineolatus(Geoze)及淡缘厚盲蝽EurystyluscostalisStl4种卵的形态、细微结构及生物学记录.利用扫描电镜对上述种类卵进行了观察、比较.首次揭示出这4种卵的卵壳表面细微结构,卵前极呼吸角形态特征及细微构造.     

木兰科7种植物花粉的扫描电镜观察

在扫描电子显微镜下对木兰科4属7种植物的花粉表面微形态进行了观察和研究,其中3种为首次报道。结果表明,7种植物的花粉均为长球形,为远极单沟花粉,两侧对称,均有穿孔或疣状突起。4属有明显的属间差异,鹅掌楸属穿孔大而显著为典型的穴-网状纹饰,含笑属具穿孔或小穴拟网状纹饰,木兰属外壁平滑具稀疏的小孔或疣状突起,木莲属具不同程度的网格状的纹饰。根据花粉的极轴长度(P)、P/E值的大小和外壁纹饰的类型,证实木兰属和含笑属较进化,木莲属和鹅掌楸属较原始,和花粉形态的分析结果一致。     

Topographic and magnetic-sensitive scanning tunneling microscope study of magnetite

The topographic and magnetic surface structure of a natural single crystal of magnetite (Fe(3)0(4)), a common mineral, has been studied from the submicrometer scale down to the atomic scale with a scanning tunneling microscope having nonmagnetic tungsten as well as ferromagnetic iron probe tips. Several different (001) crystal planes were imaged to atomic resolution with both kinds of tips. A selective imaging of the octahedrally coordinated Fe B-sites in the Fe-O planes, and even a selective imaging of the different magnetic ions Fe(2+) and Fe(3+), has been achieved, demonstrating for the first time that magnetic imaging can be realized at the atomic level.     

家蚕胚胎培养细胞的扫描电镜和透射电镜观察

用扫描电镜和透射电镜对家蚕胚胎培养细胞（ＢｍＮ＿４细胞株）进行形态学和组织学观察，细胞为圆球形，表面凹凸不平，细胞质中含有大型的颗粒。     

番木瓜感染畸形花叶病毒后的生理变化及扫描电镜观察

[目的]阐明番木瓜畸形花叶病毒(Papaya leaf-distortion mosaic virus,PLDMV)的侵染机理及侵染后番木瓜自身防御体系对抗病毒的作用机制,为番木瓜病毒病防治提供参考.[方法]以台农二号番木瓜为材料,通过RT-PCR检测接种PLDMV处理组(T)与健康空白对照组(CK)的病毒感染情况,采用分光光度法测定PLDMV侵染对番木瓜相关生理指标的影响,运用扫描电镜法观察两组番木瓜叶片的微观结构差异.[结果]通过RT-PCR检测,证明T番木瓜植株已感染PLDMV.T与CK番木瓜叶片在表征、微观解剖结构及生理指标等方面均存在明显差异,与CK番木瓜叶片相比,T番木瓜叶片纵切面栅海比及背部绒毛密度明显小于CK番木瓜,气孔密度大于CK番木瓜;T番木瓜的过氧化物酶(POD)、多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)活性和脯氨酸(Pro)、丙二醛(MDA)、超氧阴离子102714 含量均显著高于CK番木瓜(P<0.05,下同),过氧化氢酶(CAT)活性和叶绿素(Chl)含量显著低于CK番木瓜,而超氧化物歧化酶(SOD)和几丁质酶活性两组间无显著差异(P>0.05).[结论]番木瓜受PLDMV侵染后,其叶片结构被破坏,细胞毒害损伤严重,体内代谢紊乱,多种代谢调节平衡被打破,番木瓜的正常生长发育受阻.     

应用LSCM和SEM鉴定银杏花粉的倍性

以经秋水仙碱诱导获得的银杏大花粉为材料,以未经处理的正常银杏花粉为对照,利用扫描电子显微镜和激光扫描共聚焦显微镜分别观察2种花粉表面形态,并分析对比其细胞内的DNA相对荧光量与银杏大花粉核内染色体倍性关系,为正确检出银杏二倍体花粉奠定重要工作基础。研究结果表明,此方法用于花粉粒的倍性鉴定科学准确,所需试验样本少,实用性强,在植物花粉倍性鉴定中有着较好的应用前景。      

Identifying the ploidy of ginkgo pollen using laser scanning confocai and scanning electron microscope.

以经秋水仙碱诱导获得的银杏大花粉为材料,以未经处理的正常银杏花粉为对照,利用扫描电子显微镜和激光扫描共聚焦显微镜分别观察2种花粉表面形态,并分析对比其细胞内的DNA相对荧光量与银杏大花粉核内染色体倍性关系,为正确检出银杏二倍体花粉奠定重要工作基础。研究结果表明,此方法用于花粉粒的倍性鉴定科学准确,所需试验样本少,实用性强,在植物花粉倍性鉴定中有着较好的应用前景。     

Human fetal cerebellar cortex: organization and maturation of cells in vitro

Human fetal cerebellar cortex was maintained up to 5 months in vitro. Important features included early migration of granule neurons followed by maturation of Purkinje and granule neurons. Unique areas of organization developed in which a rim of leptomeningeal cells surrounded an explant and its outgrowth zone; these areas subsequently grew as well-defined units.     

Mitosis through the microscope: advances in seeing inside live dividing cells

The most visually spectacular events in the life of a cell occur when it divides. This is especially true in higher eukaryotes, where the size and geometry of cells allow the division process to be followed through a microscope with considerable clarity. In these organisms, the membrane surrounding the nucleus breaks down after the replicated DNA has condensed to form discrete chromosomes. Several new structures are then assembled to separate the chromosomes and partition the cytoplasm into two separate cells.