花椒珠心胚的超微结构及珠心细胞ATP酶的细胞化学定位

应用透射电镜对花椒（Xanthoxylum bungeanum Maxim)珠心胚原始细胞,多细胞原胚和此时期的珠心细胞及其ATP酶的分布进行了详细的观察,珠心胚原努细胞具厚的细胞壁,明显分为电子致密的外层和电子透明的内层,无胞间连丝,大的核中未见核仁,细胞质富含细胞器,多细胞原胚的壁比原始细胞的薄,电子透明,均质,具胞间连丝,核体积增大,核仁1至2个,细胞质中细胞数的数量明显增加,珠孔端的珠心细胞比胚性细胞体积大,细胞液泡化程度高,细胞质稀薄而呈现衰退趋势,ATP酶分布于液泡膜及液泡液中,与胚性细胞相接触的最内层珠心细胞胞质降解,核严重变形,最终细胞解体,此时无ATP酶活性反应。     

天麻种子萌发过程中与其共生真菌石斛小菇间的相互作用

天麻Ｇａｓｔｒｏｄｉａ ｅｌａｔａ种子与石斛小菇Ｍｙｃｅｎａ ｄｅｎｄｒｏｂｉｉ的共生萌发试验表明,石斛小菇可与天麻共生,促进天麻种子发芽并形成原球茎。菌丝主要分布于原球茎的柄状细胞、外皮层细胞和内皮层细胞,在外皮层细胞中形成菌丝结,内皮层细胞中的菌丝则被消化。原球茎细胞中的菌丝均被电子透明物质和原球茎细胞质膜包围而与球茎细胞质相隔离,菌丝进一步液泡化并最终被水解。含有衰败菌丝的原球茎细胞常被菌丝     

类杆菌的超微结构观察

对类杆菌属常见的9个菌种25个菌株作电镜观察,观察到类杆菌表面凹凸不平和纤维状物质,其细胞壁与其它革兰氏阴性杆菌一样具有三个电子致密层和二个电子透明层在菌细胞中央有电子透明区的丝状结构和电子密度高的核蛋白体。还观察到荚膜及菌体外的微泡结构。使用电予显微镜作超微结构观察有助于深入研究厌氧菌细胞的结构和功能。     

墨兰菌根的结构及酸性磷酸酶定位研究

利用光学显微镜、电子显微镜及细胞化学方法,对墨兰菌根的结构和酸性磷酸酶定位进行了初步研究。结果表明墨兰具有典型的兰科植物根结构,发现该兰花的根的外皮层不具薄壁通道细胞,菌根真菌通过破坏部分根被和外皮层细胞而侵入根的皮层细胞并在细胞内形成菌丝结,侵入的菌丝被染菌皮层细胞质膜和电子透明物质包围,进一步被消化并聚集成衰败菌丝团块。酸性磷酸酶在染菌皮层细胞及包围菌丝的皮层细胞质膜和衰败菌丝细胞壁上有强烈的酶反应,衰败菌丝周围分布有许多单层膜的含酶小泡,它们可相互愈合形成大的含酶泡或与包围菌丝的质膜融合,类似于兰科植物共生原球茎中观察到的现象。说明皮层细胞可主动释放水解酶参与对菌丝的消化     

日本白鲫外周血细胞显微及亚显微结构的研究

用光镜和电镜观察了日本白鲫外周血细胞的形态结构和过氧化物酶、糖原在血细胞内的分布。在日本白鲫外周血中，可见到红细胞、淋巴细胞、单核细胞、中性粒细胞和血栓细胞，未发现酸性粒细胞和碱性粒细胞，描述了上述各种血细胞在光镜和电镜观察下的形态和细微结构。对过氧化物酶，中性粒细胞呈阳性反应，对ＰＡＳ处理，淋巴细胞和中性粒细胞均呈阳性反应，中性粒细胞中有３种不同类型的特殊颗粒。     

天麻种子萌发过程中与其共生真菌石斛小菇间的相互作用*

天麻Gastrodiaelata种子与石斛小菇Mycenadendrobii的共生萌发试验表明,石斛小菇可与天麻共生,促进天麻种子发芽并形成原球茎。菌丝主要分布于原球茎的柄状细胞、外皮层细胞和内皮层细胞,在外皮层细胞中形成菌丝结,内皮层细胞中的菌丝则被消化。原球茎细胞中的菌丝均被电子透明物质和原球茎细胞质膜包围而与原球茎细胞质相隔离,菌丝进一步液泡化并最终被水解。含有衰败菌丝的原球茎细胞常被菌丝重新定殖。这一菌丝被消化及菌丝的重新定殖过程在整个原球茎发育过程中可不断重复发生。     

天麻种子萌发过程中与其共生真菌石斛小菇间的相互作用

天麻Gastrodiaelata种子与石斛小菇Mycenadendrobii的共生萌发试验表明,石斛小菇可与天麻共生,促进天麻种子发芽并形成原球茎。菌丝主要分布于原球茎的柄状细胞、外皮层细胞和内皮层细胞,在外皮层细胞中形成菌丝结,内皮层细胞中的菌丝则被消化。原球茎细胞中的菌丝均被电子透明物质和原球茎细胞质膜包围而与原球茎细胞质相隔离,菌丝进一步液泡化并最终被水解。含有衰败菌丝的原球茎细胞常被菌丝重新定殖。这一菌丝被消化及菌丝的重新定殖过程在整个原球茎发育过程中可不断重复发生。     

海鳗外周血细胞的显微结构

对海鳗外周血液有形成分用常规Wright氏和Giemsa氏染色并进行显微观察,可鉴别出红细胞、血栓细胞、淋巴细胞、单核细胞、中性粒细胞和酸性粒细胞;还见到幼稚的、正在分裂的、分解和解体状态的红细胞;未发现碱性粒细胞。红细胞数量多,椭圆形,具椭圆形核;白细胞中血栓细胞最多,分散分布,形态多样;淋巴细胞、单核细胞、中性和酸性粒细胞与其它鱼类的基本相似。     

天麻种子与兰小菇共生萌发过程中超微结构变化研究*

天麻Ｇａｓｔｒｏｄｉａｅｌａｔａ种子与兰小菇Ｍｙｃｅｎａｏｒｃｈｉｄｉｃｏｌａ的共生萌发试验表明兰小菇可与天麻种子共生促进天麻种子萌发并形成原球茎。菌丝自胚柄端的柄状细胞侵入天麻种子原胚,其分布被限制在天麻原球茎基部的柄状细胞、外皮层细胞和内皮层细胞内,均被电子透明物质和原球茎细胞质膜包围而与原球茎细胞质相隔离。菌丝在外皮层细胞中形成菌丝结,在内皮层细胞中则被消化,形成扁化、衰败的菌丝或菌丝四块。含有衰败菌丝的原球茎细胞可被菌丝重新定殖,新近定殖的菌丝又被原球茎细胞消化。     

天麻种子与兰小菇共生萌发过程中超微结构变化研究

天麻Ｇａｓｔｒｏｄｉａｅｌａｔａ种子与兰小菇Ｍｙｃｅｎａｏｒｃｈｉｄｉｃｏｌａ的共生萌发试验表明兰小菇可与天麻种子共生促进天麻种子萌发并形成原球茎。菌丝自胚柄端的柄状细胞侵入天麻种子原胚,其分布被限制在天麻原球茎基部的柄状细胞、外皮层细胞和内皮层细胞内,均被电子透明物质和原球茎细胞质膜包围而与原球茎细胞质相隔离。菌丝在外皮层细胞中形成菌丝结,在内皮层细胞中则被消化,形成扁化、衰败的菌丝或菌丝四块。含有衰败菌丝的原球茎细胞可被菌丝重新定殖,新近定殖的菌丝又被原球茎细胞消化。     

Histochemical and ultrastructural features of the lingual epithelium of the rat snake (Elaphe climacophora)

The histological, ultrastructural and histochemical characteristics of the lingual epithelium of the rat snake (Elaphe climacophora) were investigated by light and transmission electron microscopy. The cells in the beta-layer of the epithelium of the bifurcated apex were filled with beta-keratin fibers and an amorphous matrix. Round projections covering the surface of the epithelial cells, namely, microfacets which contained pale granules, were clearly visible on the outer faces of Oberh?utchen cells on the epithelium, and they were identified as fine granules filled with lipid. These granules might play an important role as a coating on the surface of the bifurcated lingual apex. The lipid on the surface of the lingual apex might also serve to trap and retain odorant molecules. Keratohyalin-like granules were distributed within the a-layer of the epithelium of the bifurcated apex of the tongue in the resting phase and cellular interdigitation was well developed in this region. Evidence of a shedding line was apparent under the light microscope in the cleft between outer and inner epithelial generations. The epithelial surface of the body of the tongue appeared suitable for retention of odorant and other molecules.     

Fine structure of the spermatheca and of the accessory glands in Orchesella villosa (Collembola, Hexapoda)

The spermatheca and the accessory glands of the collembolan Orchesella villosa are described for the first time. Both organs exhibit ultrastructural differences, according to the time of the intermolt in which the specimens were observed. A thick cuticular layer lines the epithelial cells of the accessory glands. In the reproductive phase, they are involved in secretory activity; a moderately dense secretion found in the apical cell region opens into the gland lumen. Cells with an extracellular cistern are intermingled with the secretory cells. These cells could be involved in fluid secretion, with the secretory product opening into the cistern which is filled with an electron-transparent material. After the reproductive phase, the gland lumen becomes filled with a dense secretion. The accessory gland secretion may play a protective role towards the eggs. The spermatheca is located between the accessory glands; its epithelium is lined by a thin cuticle forming spine-like projections into the lumen and consists of cells provided with an extracellular cistern. Secretory cells, similar to those seen in the accessory glands, are missing. Cells with a cistern could be involved in the production of a fluid secretion determining sperm unrolling and sperm motility.     

Ciliary epithelia of the mammalian eye in cultured explants

The ultrastructural characteristics of ciliary epithelium from bovine, pigmented rabbit, and fetal albino rabbit were studied in cultured explants. The tips of ciliary processes were cultured in plastic dishes with Dulbecco Modified Eagle Medium (DMEM) containing 5% fetal bovine serum. More than half of the explants adhered to the plastic culture dish, and epithelial cells spread as monolayers within a few days. Initially the explant contains two layers, the outer (nonpigmented cells) and the inner (pigmented cells). Later the explant exhibits three layers: 1) outermost lightly pigmented flattened cells, 2) an outer layer of non-pigmented cells, and 3) an inner layer of densely pigmented cuboidal cells. The cells of the outermost layer are continuous with the cells of the inner layer. A narrow space lies between the outermost layer and the outer layer. The columnar cells in the outer layer contain well developed organelles but no pigment granules; they possess a basement membrane, lateral interdigitations, and junctional complexes near their apices. Numerous focal junctions and some ciliary channel-like structures were detected between the columnar cells of the outer layer and the cuboidal cells of the inner layer. The cuboidal cells of the inner layer are filled with pigment granules. These observations suggest that the columnar cells of the outer layer are nonpigmented epithelium, the cuboidal cells of the inner layer are pigmented epithelium, and the flattened cells in the outermost layer are derived from pigmented epithelium.     

Ultrastructure of the nonhuman primate vaginal mucosa: epithelial changes during the menstrual cycle and pregnancy

Ultrastructural changes in the vaginal epithelium of the rhesus monkey during the menstrual cycle and pregnancy were studied by scanning and transmission electron microscopy. During the menstrual cycle, the epithelium was keratinized but varied in thickness. Cells of the basal and parabasal layers were polyhedral in shape but as they differentiated they accumulated glycogen and filaments. Cells in the intermediate layers had keratohyaline and membrane-coating granules. Cells in the superficial layers had a thickened cell envelope, abundant keratin filaments, electron-dense intercellular material, and focal tight junctions. The epithelial surface had numerous microridges and numerous adherent bacteria; bacteria were rare on desquamating cells. The epithelium remained keratinized for about the first month of gestation, then underwent "mucification." The cells contained abundant granules and Golgi apparatus. Concomitant with this transformation, bacteria were no longer adherent to the epithelial surface and the surface cells had microvilli instead of microridges. The epithelial changes during pregnancy were roughly associated with the changing pattern of steroid hormone secretion during gestation.     

Shell repair process in the green ormer Haliotis tuberculata: a histological and microstructural study

In the present paper, juvenile and adult shells of the green ormer Haliotis tuberculata ('Oreille de Saint-Pierre') were perforated in a zone close to the shell edge and the shell repair process was followed at two levels: (1) by observing the histology of the calcifying mantle in the repair zone and (2) by analyzing with SEM the microstructure of the shell repair zone. Histological data clearly show the presence of calcium carbonate granules into the connective tissues, but not in the epithelial cells. This suggests that calcium carbonate granules are synthesized by sub-epithelial cells and actively transported through the epithelium to the repair zone, via a process which may be similar to that described by Mount et al. [Mount, A.S., Wheeler, A.P., Paradkar, R.P., Snider, D., 2004. Hemocyte-mediated shell mineralization in the eastern oyster. Science 304, 297-300]. Furthermore, SEM observations show that the repair zone exhibits different stratified microstructures (spherulitic, thin prismatic, blocklike, sub-nacreous, nacreous, foliated-like), some of which are not continuous (i.e. lenticular) along the repair zone. This suggests a complex secreting regime of the calcifying mantle and an elaborate geometry of the epithelium involved in shell repair.     

扬子鳄消化道嗜银细胞的分布及形态学观察

该文用龙桂开浸银法对扬子鳄消化道嗜银细胞的分布及形态进行了观察。结果表明：嗜银细胞分布于整个消化道中,从食道到直肠。其中,十二指肠和回、直肠交接处密度很高,胃体及直肠很低。嗜银细胞形态多样。食道嗜银细胞位于上皮基部和固有膜中,呈椭圆形或不规则形。胃嗜银细胞位于胃腺部,圆形或椭圆形,有的可见明显的胞突。肠嗜银细胞位于上皮细胞之间,呈长柱形、纺锤形、长颈瓶形或锤状。多数细胞两端有较长胞突,分别与固有膜     

Fine-structural and chemical analyses on inner and outer sheath of the cyanobacteriumGloeothece sp. PCC 6909

Cells of the unicellular cyanobacteriumGloeothece sp. PCC 6909 are surrounded by an inner (enclosing 1–2 cells) and an outer (enclosing cell groups) sheath. Using conventional Epon-embedding in combination with ruthenium-red staining, the inner and outer sheaths appeared similar and displayed multiple bands of electron-dense subunits. However, embedding in Nanoplast resin to avoid shrinkage led to the detection of two distinct zones (inner and outer zone) each with several distinct layers. The zone delimited by the electron-dense thick inner sheath layer, and the zone enclosed by the thin electron-dense outer sheath layer, are composed of a homogeneous material of little electron-contrast. Whereas the outer zone appears to be of even contrast, the inner zone is characterized by a distinct electron-transparent layer. Element distribution analysis revealed that the electron-transparent layer contained relatively large amounts of sulfur, carbon, and oxygen but only little nitrogen.Inner and outer sheath fractions were isolated by differential mechanical cell breakage and centrifugation. The outer sheath fraction was less hydrated than the inner one. The two fractions differed little in their contents of uronic acids, carbohydrate and protein, although the outer sheath fraction contained less sulfate. A soluble polysaccharide with a chemical composition similar to that of inner and outer sheath fractions was also obtained from the culture supernatant.     

Wound healing in the cornea of the chick embryo

Spatio-temporal changes in the shapes of the epithelial cells in culture were followed with the aid of scanning electron microscopy. On a substratum that enables the epithelium to spread extensively, the first remarkable change in shapes of the cells occurred at the margin of epithelium at 12 h of culture. The marginal cells formed leading edges with filo- or lamellipodia, flattened, and lost microvilli on surface. In accordance with those changes, the borderlines among cells became almost indiscrenible. Flattening of the cells was the essential characteristic associated with active epithelial spreading throughout the culture period. Elongation of cells of intermediate zone at right angles to the direction of the locomotion of the marginal cells at 24 h of culture was the second significant change. As the third, the change from the ordinary pentagonal or hexagonal to extraordinary tetragonal or other polygonal shapes, with or without irregular margins, began in cells of the intermediate area at 24 h and propagated to those in inner area. The active deformation of the inner cells with no space in which to move was considered to play some role in the extensive epithelial spreading.     

Histological and Ultrastructural Studies on the Conjunctiva of the Barred Owl (Strix varia)

This report is the first characterization of the histology and ultrastructure of the barred owl conjunctiva. The inferior eyelid was dominated by a large disk-shaped plate covered by a non-keratinized stratified squamous or cuboidal epithelium of variable thickness. The apical surface of the plate epithelium varied from flat to long microvilli or even short cytoplasmic extensions similar to those seen in the third eyelid. All specimens had a few goblet cells filled with mucous secretory granules in the plate region. The underlying connective tissue was a dense fibroelastic stroma. Eosinophils were surprisingly common in the epithelial layer and underlying connective tissue in the plate and more distal orbital mucosal region. The orbital mucosa contained goblet cells with heterogeneous glycosylation patterns. The leading edge and marginal plait of the third eyelid are designed to collect fluid and particulate matter as they sweep across the surface of the eye. The palpebral conjunctival surface of the third eyelid was covered by an approximately five-cell-deep stratified squamous epithelium without goblet cells. The bulbar surface of the third eyelid was a bilayer of epithelial cells whose superficial cells have elaborate cytoplasmic tapering extensions reaching out 25 μm. Narrow cytofilia radiated outwards up to an additional 15–20 μm from the cytoplasmic extensions. Lectin labeling demonstrated heterogeneous glycosylation of the apical membrane specializations but only small amounts of glycoprotein-filled secretory granules in the third eyelid.