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.     

Nucleoside phosphatases of fetal and maternal blood cells: electron microscope study

Surface membranes of the blood cells located within the maternal blood sinuses of the rat placenta contain reaction products of nucleoside phosphatases. Fetal blood cells separated from maternal blood by the placental labyrinth show no activity during normal or prolonged gestation. Neonatal blood cells examined 34 hours after parturition show these enzyme activities.     

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。     

Glucans of oomycete cell walls

The cell walls of selected oomycetous fungi are composed primarily of glucans, and cellulose constitutes a relatively small proportion of the total glucan. The noncellulosic constituents consist of acid-soluble glucan or glucans and insoluble glucan or glucans. These noncellulosic glucan fractions contain beta-(1-->3) glucosidic linkages and apparently beta-(1-->6) linkages also.     

A major constituent of brown algae for use in high-capacity Li-ion batteries

The identification of similarities in the material requirements for applications of interest and those of living organisms provides opportunities to use renewable natural resources to develop better materials and design better devices. In our work, we harness this strategy to build high-capacity silicon (Si) nanopowder-based lithium (Li)-ion batteries with improved performance characteristics. Si offers more than one order of magnitude higher capacity than graphite, but it exhibits dramatic volume changes during electrochemical alloying and de-alloying with Li, which typically leads to rapid anode degradation. We show that mixing Si nanopowder with alginate, a natural polysaccharide extracted from brown algae, yields a stable battery anode possessing reversible capacity eight times higher than that of the state-of-the-art graphitic anodes.     

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。     

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.     

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     

Procion brown: an intracellular dye for light and electron microscopy

Procion browvn has been used to inject lamprey giant interneutros. The dye is opaque to both light and electrons, and imparts a pink color to the neuron in situ during iontophoresis. It has the advantage over cobaltolus chloride that postinjection treatment with ammonium sulfide is eliminated and the integrity of the surrounding neuropil is ensured.     

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。     

The fine structure of fossil plant cell walls

The cell walls of sieve elements in the primary phloem of the Carboniferous fern Tubicaulis contain structural features that morphologically resemble cellulose microfibrils in extant plants. This may be the oldest example of distinct fibrillar structures in the fossil record. The possible identity and significance of these features are discussed and their structure is compared with that of cell walls in other fossil and extant plants.     

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.     

大鼠感染肝片吸虫后红细胞过氧化损伤的实验研究

本文通过大鼠感染肝片吸虫复制感染模型，研究肝片吸虫诱导红细胞脂质过氧化损伤，将60只大鼠随机分成试验组（n=30）和对照组（n=30)，试验组大鼠一次口服25个囊蚴，对照组不感染，于感染前和感染后9周采血制备样本，检测GSH－Px,SOD,GST活性和MDA含量，结果表明大鼠感染肝片吸虫后，溶血液中GSH－Px活性的变化不明显，总体变化趋是升高，但整个实验期，两组差异不显著（P＞0．05），SOD和GST活性的变化不明显，MDA含量总体变化趋势是或高，在第3，7周与对照期差异显著（P＜0．05），证实肝片吸虫感染后，红细胞发生了脂质过氧化作用，自由基参与肝片吸虫病的发展过程。     

Altered growth and cell walls in a fucose-deficient mutant of Arabidopsis

A biochemical screening procedure was developed to identify mutants of Arabidopsis thaliana in which the polysaccharide composition of the cell wall was altered. Over 5000 ethyl methanesulfonate-mutagenized plants were analyzed by this method, leading to the identification of 38 mutant lines. One complementation group of mutants was completely deficient in l-fucose, a constituent of pectic and hemicellulosic polysaccharides. These mutant plants were dwarfed in growth habit, and their cell walls were considerably more fragile than normal.