正中隆起室管膜面赘生物及其形成过程的电镜观察

在正常SD雄性大鼠（2周龄-27月龄）第三脑室底正中隆起前缘附近，本研究用扫描电镜观察到有呈圆柱状中空赘生物出现。该赘生物可分为基底部、体部及末梢部，其直径为2-10μm，长度为2-230μm。通过观察该赘生物的形成过程，有理由认为它是室管膜细胞过度增生所致，但与室管膜瘤不同。     

柠檬酸铝抗二氧化硅细胞毒作用的扫描电镜观察

柠檬酸铝是一种较有前途的矽肺防治药物。以往应用生物化学的方法观察到,柠檬酸铝具有抗二氧化硅细胞毒的作用。本文通过扫描电镜观察豚鼠肺泡巨噬细胞表面,又从形态学上研究了柠檬酸铝对二氧化硅细胞毒作用的影响。结果表明,正常豚鼠肺泡巨噬细胞呈圆形或卵圆形,有丰富的不规则折迭和微绒毛突起的不均一表面,有的带有细长伪足;一定剂量的二氧化硅粉尘与巨噬细胞孵育30分钟后,可观察到细胞正在吞噬粉尘,此时细胞表面已有改变,微绒毛消失,折迭明显变浅,孵育3.5小时后,胞体缩小,表面结构消失,呈岩石样外观,有些细胞     

水生动物病毒的电镜和荧光显微镜观察

应用透射电镜和荧光显微镜对三种水生动物病毒粒子形态、病毒感染细胞的超微结构变化及亚细胞定位进行比较和研究。负染电镜观察显示:鳜鱼弹状病毒(SCRV)粒子呈典型的子弹状形态,长约76～118 nm,直径约29～52 nm;鲈鱼呼肠孤病毒(LJRV)粒子呈正二十面体结构,具有双层衣壳,直径约70～80 nm;蛙虹彩病毒(RGV)粒子呈正二十面体结构,具有囊膜,直径大小约150 nm。超薄切片观察表明,宿主细胞的基本结构遭到不同程度的破坏,成熟病毒粒子分布在胞质中或以出芽的方式释放到胞外,且RGV增殖后在胞质中聚集形成晶格状结构。免疫荧光观察进一步显示,RGV感染细胞后能产生多个直径大小不一的包涵体。本研究结果有助于了解和认识水生动物病毒的超微形态特征、复制过程及致病机理。     

腹股沟肉芽肿的超微结构观察

目的:探讨腹股沟肉芽肿的组织结构和超微结构病变特征.方法:对2例腹股沟肉芽肿患者的病变组织进行光镜和透射电镜观察.结果:光镜下,肉芽肿组织内有大量巨噬细胞,其胞质内可查见革兰氏阴性的肉芽肿荚膜杆菌;透射电镜下巨噬细胞胞质内可见较大的初级溶酶体和大量形态各异、大小不等的次级溶酶体和板层样膜状结构的吞噬体(即杜诺凡小体),偶见吞噬体内有菌体剖面或其残片.结论:杜诺凡小体是巨噬细胞吞噬肉芽肿荚膜杆菌后在胞质溶酶体内形成的形态各异、大小不等的吞噬体,其超微结构形态学特征,具有临床诊断的意义.     

支气管淀粉样变沉积症病的超微结构观察

在左总支气管淀粉样变沉积症病人手术过程中，取病变组织进行光镜和电镜观察。电镜下见淀粉样沉积物呈块状分布于细胞外，染色灰淡，由不规则排列的5～10nm的细丝样结构组成。沉淀样物附近可见活跃的成纤维细胞和巨噬细胞分布。成纤维细胞体积大，胞质中有发达的高尔基体和丰富的粗面内质网，内质网扩张、充满染色灰淡的细丝样物质，与细胞外沉积物形态近似，提示淀粉样沉积物可能来源于成纤维细胞。巨噬细胞胞质中有多种吞噬体，其中有的内容物为染色灰淡的块状物，其形状与细胞上淀粉物中的块状噬斑相似，提示部分淀粉样沉积物可能被巨噬细胞所清除。     

胎儿垂体前叶的超微结构

为了阐明人胚胎期垂体前叶细胞的发育状况。收集16～40周胎令的新鲜胎儿17例。将其前叶固定于4％戍二醛液内,1％锇酸后固定,Epon812包埋,超薄切片,JEM—100CXⅡ透射电镜观察。根据观察所见前叶细胞的超微结构特点,我们将胚胎期前叶细胞分成四种类型:未分化型细胞;分化中细胞,已分化细胞及退化中细胞。它们各自的形态结构是:1.未分化细胞、胞体较小,胞质少而电子密度低,细胞器极少,偶见小的线粒体或内质网。核内染色质多呈细沙粒状。核仁较少而小。2.分化中细胞,胞体增大呈多形性,随细胞类型不同,胞质电子密度不一,其共同特点是,细胞器发达,尤其是线粒体和内质网显著增多,粗     

豚鼠内耳螺旋器毛细胞的超微结构特征

内耳螺旋器毛细胞是接受不同声波振幅和频率的特殊细胞 ,尽管它的来源、衍发及细胞属性尚未获得统一认识[1,2 ] ,但其功能则尽人皆知。本研究拟从超微形态角度对该细胞进行深入探索。样品取自豚鼠内耳 ,断头处死动物取出耳蜗 ,沿骨蜗管外壁开几个小孔后 ,迅速投入 4 %戊二醛固定液 ,0 5ｈ后修整并轻取螺旋器 ,继续固定 ,常规脱水、包埋、半薄切片定位、超薄切片、透射电镜观察。电镜观察 :内毛细胞呈曲颈瓶状 ,胞体顶端游离面可见三排平行纵列的微绒毛 (静纤毛 ) ;外毛细胞呈圆柱状 ,微绒毛亦三行 ,但并列成“Ｖ”或“Ｗ”形[1,3 ] 。二者…     

胚鼠大脑皮质神经细胞体外培养的扫描电镜观察

本文采用胚鼠大脑皮层神经细胞原代分离单层培养的细胞,分别于培养后第3、8、10、14、17、22天取材。经1％戊二醛固定,各级酒精脱水,临界点干燥,喷金,S—450扫描电镜观察。根据神经细胞在体外生长的连续观察,从第三天开始,神经细胞有突起生长,于第六天至第九天,神经细胞胞体逐渐增大,双极或多极细胞已基本分化清楚,神经细胞突起生长,相互间呈网状交错。于第十天至第十七天的神经细胞胞体增大,突起增粗,可见主树突上完好的分支。高倍观察可在胞体及粗大突起上看到多个突触。十     

Vero细胞在微载体上迁移和多层生长现象

本文通过对电子显微镜观察了Ｖｅｒｏ细胞有微载体增减过程中的迁移民政部发现在不同增减阶段，Ｖｒｏ细胞迁移方式不同；在分泌形成的细胞外基质，上，Ｖｅｒｏ细胞迁移是通过 层粘连蛋白介导进行的，被层粘连蛋白抗体抑制；这种迁移导致Ｖｅｒｏ细胞在微载体上形成多层生长现象。     

糖皮质激素对正中隆起室管膜细胞的影响

正中隆起位于下丘脑内侧基底部 ,通过垂体柄与垂体相连。其正上方为第三脑室 ,第三脑室腔面为室管膜细胞。从正中隆起的神经联系和血管分布来看 ,它是下丘脑 -垂体 -内分泌轴上传下达的关键部位 ,与多种激素及其它信息的传递和调控有关 ,我们利用扫描电镜观察了糖皮质激素醋酸可的松对大鼠正中隆起室管膜细胞的影响。材料与方法1 .动物分组和给药　雄性 SD大鼠 2 0只 ,体重 2 5 0～ 2 80 g,随机分为 2组 ,每组 1 0只 :正常对照组 ,0 .9%的生理盐水 0 .3ml后肢肌肉注射 ,每天一次 ,连续 31天。可的松组 ,醋酸可的松混悬液充分混匀 ,每只按 2…     

The three-dimensional structure of the clear zone of a cultured osteoclast

Osteoclasts collected from long bones of newborn mice were cultured on dentine slices. Then, osteoclasts were sectioned by alternating semithin and ultrathin sections, and the three-dimensional reconstruction was made by the serial semithin sections. By this method, the present study showed first the three-dimensional structure of an osteoclast, especially the clear zone. A reconstructed osteoclast with complicated contours shifted from the lacuna, and its clear zone was a ring-shaped structure. By TEM, a new small lacuna was formed under the ruffled border, and the clear zone could be further classified into three types. The present study suggested that the synthetic observations of both three-dimensional structure and ultrastructure by transmission electron microscopy were necessary to determine whether the osteoclast was resorbing or migrating. According to these observations, the reconstructed osteoclast seemed to be migrating.     

Efficient three-dimensional reconstruction of synapse with high-voltage electron microscopy

Three-dimensional (3-D) information on nervous tissue is essential for the understanding of brain function. Especially, 3-D synaptic analyses on serial ultrathin sections with transmission electron microscopy (TEM) have contributed to the knowledge on neural plasticity associated with various pathophysiological conditions. The 3-D reconstruction procedures, however, not only require a great amount of expertise but also include time-consuming processes. Here, we carried out computer-assisted 3-D reconstruction of parallel fibre-Purkinje cell synapses based on 250 nm serial sections using high-voltage electron microscopy (HVEM). The 3-D synapse models were constructed more efficiently and rapidly compared with conventional serial TEM reconstruction. This result suggests that 3-D reconstruction with thicker sections and HVEM is a useful method to study synaptic connectivity.     

人舌鳞癌组织超薄切片的AFM成像和切割

利用一种基于电镜超薄切片法改进的制样方法，将人舌鳞状细胞癌病理组织以环氧树脂包埋并切片后，将薄片平整地贴附在云母上，用原子力显微镜(AFM)对切片表面进行研究，可以得到高分辨率的细胞超微结构图像，局部的亚细胞水平的形态结构可以与电镜下得到的图像相比拟。在此基础上，利用AFM针尖对肿瘤细胞核内特定区域进行切割和操纵，形成生物分子的堆积，从而为拾取(pjck—up)和进一步用分子生物学手段在亚细胞基因水平研究人舌鳞癌的病理学奠定了基础。     

Investigation of the degradation of smooth SiGe epitaxial layer on Si substrate

The degradation of smooth SiGe epitaxial layer was investigated by transmission electron microscopy (TEM), X-ray reflectivity (XRR) and atomic force microscopy (AFM). It was shown from AFM results that the crosshatch was formed with increasing annealing temperature, which indicated the degradation of smooth surface. The surface degradation was caused by the internal dislocations, which were observed by plan-view TEM (PTEM) and cross-sectional TEM (XTEM). From XTEM, the sharp interface between SiGe top layer and Si substrate was broadened and there were a lot of 60° dislocations formed in SiGe top layer, which resulted in the crosshatch on the surface. The crosshatch was also verified by PTEM.     

竹叶状ZnS纳米带的生成与表征

通过无催化物理热蒸发ZnS粉末的方法成功地制备了一种新颖的竹叶状ZnS纳米带。X射线衍射分析和扫描电镜透射电子显微镜,用来对ZnS生长物进行表征,检测显示,所制得的竹叶状纳米带的厚度50～100nm,度宽500～600nm,长度数十微米。透射电镜和选区电子衍射花样表明,制备的纳米带是单晶六角纤锌矿结构。样品的光学性能显示在424nm处有一个强烈的蓝光发射,这种发射是由于氧空位和其他表面态造成的。同时对纳米带的生长机制作了论述。     

纳米BiVO_4的微波合成及其光催化性质

以五水硝酸铋和五氧化二钒为原料,通过微波合成法制备了纳米BiVO4,采用X-射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)表征了样品的形貌、结构和特性。XRD表明所制备的样品是纯的单斜晶型BiVO4;SEM显示样品的形貌呈层状结构;TEM进一步指出这些片层结构是由小粒子聚集而成的多孔结构。以催化降解甲基橙来考察其光催化性能。在100mL的10mg/L甲基橙溶液中加入0.12g经673K恒温热处理2h后的BiVO4及0.2mL H2O2,调节pH值为3.0,在可见光下照射90min后,降解率达到94.70%,催化性能良好。     

Abnormal formation of the glucan network from regenerating protoplasts in Schizosaccharomyces pombe cps8 actin point mutant

To study the close relationship between the actin cytoskeleton and cell wall formation, the process of cell wall formation in reverting protoplasts of the fission yeast, Schizosaccharomyces pombe, cps8 actin point mutant was investigated by ultra-high-resolution low-voltage scanning electron microscopy (UHR-LVSEM) and transmission electron microscopy (TEM). The protoplast of the cps8 mutant began to form a glucan network in a unipolar manner and to secrete alpha-galactomannan. The site of cell wall formation grew in a cylindrical shape in the wild-type protoplast. The alpha-galactomannan did not fill in the intrafibrillar spaces completely, however, and the fibrils were exposed on the cell surface. UHR-LVSEM images indicated that the glucan fibrils were thin and rope-shaped, forming a looser network than the wild-type. TEM images indicated the finest fibrils were approximately 1.5 nm in diameter, the same diameter as the wild-type. These results suggest that the cps8 mutant was insufficient in developing cross-linkage with the glucan fibrils up to the wide ribbon shape as found in the wild-type [Osumi M et al. (1989) J. Electron Microsc. 38: 457-468; Osumi M (1998) Micron 29: 207-233]. These findings appear to indicate that the actin cytoskeleton controls formation of the glucan network and secretion of beta-1,6-glucan, and confirm the close relationship of the actin cytoskeleton and glucan formation.     

大鼠侧脑室及其脉络丛室管膜上皮的超微结构观察

采用扫描和透射电子显微镜研究大鼠侧脑室及其脉络丛室管膜上皮的超微结构特征，并探讨其功能。扫描电镜观察结果：侧脑室壁室管膜上皮细胞游离端呈不规则多边形，可见纤毛及微绒毛，偶见分泌泡，脉络丛上皮细胞游离端微绒毛及分泌泡丰富，纤毛光见，可见、丛上细胞”。透射电镜观察发现，侧脑室壁及脉络丛上皮均由单层立方上皮组成，但二类上皮细胞的超微结构明显有别，室管膜上皮表面可见纤毛及微绒毛，分泌泡少见，脉络丛上皮游离端微绒毛丰富，常吻合成迷路样网，微绒毛的顶端膨大，形成微顶浆分泌小泡，胞浆内细胞器丰富，大鼠侧脑室壁及脉络丛上皮超微结构的差异反映二者功能的不同，本研究认为侧脑室脑脊液分泌的主要部位是脉络丛，其分泌的方式除脉络丛上皮细胞的主动运输功能外，可能微顶浆分泌法是侧脑室脑脊液形成的主要方式。     

Development of a high temperature-atmospheric pressure environmental cell for high-resolution TEM

An environmental cell for high-temperature, high-resolution transmission electron microscopy of nanomaterials in near atmospheric pressures is developed. The developed environmental cell is a side-entry type with built-in specimen-heating element and micropressure gauge. The relationship between the cell condition and the quality of the transmission electron microscopic (TEM) image and the diffraction pattern was examined experimentally and theoretically. By using the cell consisting of two electron-transparent silicon nitride thin films as the window material, the gas pressure inside the environmental cell is continuously controlled from 10(-5)?Pa to the atmospheric pressure in a high-vacuum TEM specimen chamber. TEM image resolutions of 0.23 and 0.31?nm were obtained using 15-nm-thick silicon nitride film windows with the pressure inside the cell being around 5?×?10(-5) and 1?×?10(4)?Pa, respectively.     

Ultrastructure and behavior of actin cytoskeleton during cell wall formation in the fission yeast Schizosaccharomyces pombe

Fluorescence microscopy has shown that F-actin of the fission yeast Schizosaccharomyces pombe forms patch, cable and ring structures. To study the relationship between cell wall formation and the actin cytoskeleton, the process of cell wall regeneration from the protoplast was investigated by transmission electron microscopy (TEM), immunoelectron microscopy (IEM) and three-dimensional reconstruction analysis. During cell wall regeneration from the protoplast, localization of F-actin patches was similar to that of the newly synthesized cell wall materials, as shown by confocal laser scanning microscopy (CLSM). In serial sectioned TEM images, filasomes were spherical, 100-300 nm in diameter and consisted of a single microvesicle (35-70 nm diameter) surrounded by fine filaments. Filasomes were adjacent to the newly formed glucan fibrils in single, cluster or rosary forms. By IEM analysis, we found that colloidal gold particles indicating actin molecules were present in the filamentous area of filasomes. Three-dimensional reconstruction images of serial sections clarified that the distribution of filasomes corresponded to the distribution of F-actin patches revealed by CLSM. Thus, a filasome is one of the F-actin patch structures appearing in the cytoplasm at the site of the initial formation of the cell wall and it may play an important role in this action.