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Study on the Ultrastructures of Antennal Sensilla in Helicoverpa armigera 被引量:2
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作者 WANG Gui-rong, GUO Yu-yuan and WU Kong-ming( State Key Laboratory of Plant Disease and Insect Pests, The Institute of Plant Protection , Chinese Academy of Agricultural Sciences, Beijing 100094 , P. R . China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第8期896-899,共7页
The morphology and structures of antennal sensilla of Helicoverpa armigera are observed under scanning and transmission electron microscopes. Antennae of Helicoverpa armigera are made up of scapus, pedicel and flagell... The morphology and structures of antennal sensilla of Helicoverpa armigera are observed under scanning and transmission electron microscopes. Antennae of Helicoverpa armigera are made up of scapus, pedicel and flagellum that the latter consists of 70 - 82 segments. The inner side surface of antenna is cat-aphracted and most of the antennal sensilla lie on its outer, upper and lower surfaces. Both the antennae of male and female contain five kinds of antennal sensilla, namely, sensillum trichodeum, sensillum basicon-icum, sensillum chaeticum, ear-shaped sensillum and sensillum coeloconicum, and the kinds, number and distribution of antennal sensilla of both sexes are similar. There are a large number of serrate cuticular processes on antennal surface, especially on the middle and basic parts of antenna. Sensillum trichodeum and sensillum basiconicum, the main chemical odor receptors on antennae of Helicoverpa armigera, consist of cuticular-wall, sheath cells, lymph and dendrites. There are significant differences between the internal structures of the two kinds of sensilla. In sensillum trichodeum, the cuticular-wall is thicker, less lipophilic pore channels and has one or a few dendrites, while in sensillum basiconicum, the cuticular-wall is thinner, abundant lipophilic pore channels and has much more dendrites. 展开更多
关键词 Helicoverpa armigera Antennal sensillum ultrastructures Scanning electron microscope Transmission electron microscope
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Therapeutic Actions of the Chinese Herbal Formulae with Cold and Heat Properties and Their Effects on Ultrastructures of Synoviocytes in Rats of the Collagen-Induced Arthritis 被引量:5
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作者 李梢 吕爱平 +1 位作者 贾宏伟 王友京 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2002年第4期296-302,共7页
The therapeutic actions of Qing Luo Yin (QLY清络饮) with heat property and Wen Luo Yin (WLY温络饮) with cold property on pain, swelling of the ankle, arthritis index and ultrastructures of synoviocytes were compared i... The therapeutic actions of Qing Luo Yin (QLY清络饮) with heat property and Wen Luo Yin (WLY温络饮) with cold property on pain, swelling of the ankle, arthritis index and ultrastructures of synoviocytes were compared in rats of type II collagen-induced arthritis (CIA), with tripterygium glycosidorum (TG) used as control. The results indicated that both QLY and WLY could reduce pain, swelling of the ankle and the arthritis index of CIA, and QLY had better effects in reducing the swelling of the ankle and controlling the secondary pathological lesions as compared with WLY. Investigation on the ultrastructures of synoviocytes indicated that both QLY and WLY could reduce the number of Golgi apparatus, rough surface endoplasmic reticulum, dense bodies, matrix filaments and vacuoles so as to suppress the excessive secretion of synoviocytes in rats of CIA. 展开更多
关键词 Therapeutic Actions of the Chinese Herbal Formulae with Cold and Heat Properties and Their Effects on ultrastructures of Synoviocytes in Rats of the Collagen-Induced Arthritis RER
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A Srudy on Ultrastructures of Normal 5-8 Week Human Placental Villi
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作者 Li Shulan Zhu Qiding.(ACTA ACADEMIAE MEDICINAE NANJING,1994,14(1):26-29) 《The Journal of Biomedical Research》 CAS 1994年第1期21-21,共1页
Fourteen normal human placental villi at a fetal age of 5-8 weeks were examined withelectron microscope. The results were vide infra.(1)The cytotrophoblasts were characterized by largenucleus with less heterochromatin... Fourteen normal human placental villi at a fetal age of 5-8 weeks were examined withelectron microscope. The results were vide infra.(1)The cytotrophoblasts were characterized by largenucleus with less heterochromatin and prominent nucleolus with a number of free polyribosomes as well asscattered mitochondria in the cytoplasm.(2) There was a layer of dense microvilli on the surface of thesyncytiotrophoblastic cells.The size and shape of microvilli were variable. Usually fine globular expansions were present at the apical pole of microvilli and the cell membrane between the base of microvillihad invaginations into the cytoplasm forming small vesicles and tubules. Rough endoplasmic reticulum,free polyribosomes,mitochondria, lipid droplets and few myelinlike figures were also found in the cytoplasm.Part of cytoplasm penetrated into the interspaces of cytotrophoblastic cells and became in directcontact with the basement membrane.(3) Numerous desmosomes were seen between the cells of cytotrophoblast and syncytiotrophoblast.And (4) in the strom a of villi,mesenchymal cells were abundant inrough endoplasmic reticulum and well developed Golgi complex. Mesenchymat cells were markedlyfunctionally active. Ultrastructural characteristics of placental villin in connexion with their functionwere discussed. 展开更多
关键词 placental villi early pregnancy ultrastructure
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Inactivation of Cryptosporidium by ozone and cell ultrastructures 被引量:11
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作者 Zhilin Ran Shaofeng Li +3 位作者 Junli Huang Yixing Yuan Chongwei Cui Craig Denver Williams 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第12期1954-1959,共6页
The fluorescence staining method and scanning electron microscopy (SEM) were used to study the effect of ozone (O3) inactivating Cryptosporidium in water and cell ultrastructures variation to shed light on the mec... The fluorescence staining method and scanning electron microscopy (SEM) were used to study the effect of ozone (O3) inactivating Cryptosporidium in water and cell ultrastructures variation to shed light on the mechanism of inactivation preliminarily. Results indicated that O3 had a stronger inactivating capability. When the concentration of O3 was above 3.0 mg/L and the contact time was up to 7 min, a significant inactivating effect could be achieved. The turbidity on inactivation effects was also found to be statistically significant in artificial water. With increases in turbidity, the inactivating effect decreased. Inactivation rate improved with a temperature increase from 5 to 25℃, but decreased beyond this. The inactivating capability of O3 was found to be stronger under acidic than that under alkalic conditions. When the concentration of organic matter in the reaction system was increased, the competition between Cryptosporidium and organics with O3 probably took place, thereby reducing the inactivation rate. In addition, the cellular morphology of Cryptosporidium varied with different contact times. At zero contact time, cells were rotundity and sphericity, at 60 sec they became folded, underwent emboly, and burst at 480 sec, the cell membrane of Cryptosporidium shrinked and collapsed completely. 展开更多
关键词 OZONE INACTIVATION CRYPTOSPORIDIUM ultrastructures
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Cell wall ultrastructures of the Proterozoic acritarch Leiosphaeridia asperata and their implications for biological affinity 被引量:2
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作者 GONG Miao ZHOU ChuanMing +2 位作者 YIN LeiMing YUAN XunLai WANG ChunZhao 《Science China Earth Sciences》 SCIE EI CAS 2010年第12期1750-1755,共6页
Abundant sphaeroidal acritarch Leiosphaeridia asperata,with vesicle size ranging from 13 to 360 μm,occurred in the Proterozoic Liulaobei Formation shales in Huainan,Anhui Province.TEM/SEM studies of these sphaeroidal... Abundant sphaeroidal acritarch Leiosphaeridia asperata,with vesicle size ranging from 13 to 360 μm,occurred in the Proterozoic Liulaobei Formation shales in Huainan,Anhui Province.TEM/SEM studies of these sphaeroidal acritarchs have revealed complex ultrastructures,including ridges,bands,and possible trilaminar structures(TLS).Ridges,spaced ~1 μm apart,are distributed regularly on the vesicle internal surface of one specimen.Some specimens have alternating electron-dense and electron-tenuous bands that are perpendicular to vesicle walls.Some specimens have trilaminar structures(TLS),while a few others have both bands and TLS.These wall ultrastructures provide evidence that the Liulaobei leiosphaerids are of green microalgae.The variation in wall ultrastructures may represent various stages in a life cycle or developmental phases in the cyst formation analogous to some modern chlorophyceaen microalgae. 展开更多
关键词 ULTRASTRUCTURE AFFINITY Leiosphaeridia asperata PROTEROZOIC Liulaobei Formation
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Ultrastructures in the Spirotheca of Fusulinella (Fusulinid foraminifer)
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作者 杨湘宁 郑洪 《Science China Chemistry》 SCIE EI CAS 1993年第6期751-758,共8页
An SEM study has been conducted to examine the ultrastructures in the spirotheca of Fusulinella and to reveal the ultra-features of the basic layers consisting of the spirotheca of Fusulinella. The study has demonstra... An SEM study has been conducted to examine the ultrastructures in the spirotheca of Fusulinella and to reveal the ultra-features of the basic layers consisting of the spirotheca of Fusulinella. The study has demonstrated that the diaphanotheca in the spirotheca of Fusulinella could be considered as a secondary structure. 展开更多
关键词 fusulinid FORAMINIFERS ULTRASTRUCTURE of TEST wall.
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Myelin histology:a key tool in nervous system research 被引量:1
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作者 Óscar Darío García-García Víctor Carriel Jesús Chato-Astrain 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期277-281,共5页
The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various... The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental conditions.Today,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience research.In this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining methods.Considering the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques. 展开更多
关键词 fluorescence microscopy HISTOLOGY light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing
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Eco-physiological characteristics of Tetracentron sinense Oliv.saplings in response to different light intensities
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作者 Rong Wang Xueheng Lu +4 位作者 Hongyan Han Xuemei Zhang Yonghong Ma Qinsong Liu Xiaohong Gan 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期29-44,共16页
The regeneration of Tetracentron sinense Oliv.is poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in gaps.It is unclear whether different ... The regeneration of Tetracentron sinense Oliv.is poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in gaps.It is unclear whether different light intensities in various habitats affect eco-physiological characteristics of saplings and their natural regeneration.In this study,the light intensity in T.sinense habitats was simulated by artificial shading(L1:100%NS(natural sunlight)in the open;L2:50%NS in a forest gap or edge;L3:10%NS in understory)to investigate differences in morphology,leaf structure,physiology,and photosynthesis of 2-year-old sap-lings,and to analyze the mechanism of light intensity on sapling establishment.Significant differences were observed in morphology(including leaf area,and specific leaf area)under different light intensities.Compared to L1 and L3,chloroplast structure in L2 was intact.With increasing time,superoxide dismutase(SOD)and catalase(CAT)activities in L2 became gradually higher than under the other light intensities,while malondialdehyde(MDA)content was opposite.Shading decreased osmoregulation substance contents of leaves but increased chlorophyll.The results suggest that light intensities significantly affect the eco-physiological characteristics of T.sinense saplings and they would respond most favorably at intermediate levels of light by optimizing eco-physiological characteristics.Therefore,50%natural sunlight should be created to promote saplings establishment and population recovery of T.sinense during in situ conservation,including sowing mature seeds in forest edges or gaps and providing appropriate shade protection for seedlings and saplings in the open. 展开更多
关键词 Chloroplast ultrastructure Eco-physiological characteristics Light intensities Sapling establishment Tetracentron sinense Oliv
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Ultrastructure of the compound eye of Longitarsus lewisii(Baly,1874)(Coleoptera,Chrysomelidae)
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作者 LIANG Zu-Long ZHANG Tian-Hao +1 位作者 LI Wen-Jie GE Si-Qin 《环境昆虫学报》 CSCD 北大核心 2024年第6期1316-1325,共10页
In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D re... In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D reconstruction.The compound eye of L.lewisii was of the apposition type,with an average of 121.88±7.64 ommatidia in males and 119.00±4.71 ommatidia in females.Each ommatidium was composed of a biconvex cornea,an acone consisting of four cone cells,eight retinular cells along with the rhabdom,two primary pigment cells,and numerous secondary pigment cells.The open type of rhabdom in L.lewisii consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells(R1~R6)and two vertically attached central rhabdomeres contributed by R7 and R8 respectively.The orientation of microvilli suggested a weak sensitivity to polarized light perception. 展开更多
关键词 ULTRASTRUCTURE compound eye Longitarsus lewisii leaf beetle 3D reconstruction
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Time-dependent impact of a high-fat diet on the intestinal barrier of male mice
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作者 Carolline Santos Miranda Daiana Araujo Santana-Oliveira +4 位作者 Isabela Lopes Vasques-Monteiro Nathan Soares Dantas-Miranda Jade Sancha de Oliveira Glauser Flavia Maria Silva-Veiga Vanessa Souza-Mello 《World Journal of Methodology》 2024年第1期114-123,共10页
BACKGROUND Excessive saturated fat intake compromises the integrity of the intestinal mucosa,leading to low-grade inflammation,impaired mucosal integrity,and increased intestinal permeability,resulting in the migratio... BACKGROUND Excessive saturated fat intake compromises the integrity of the intestinal mucosa,leading to low-grade inflammation,impaired mucosal integrity,and increased intestinal permeability,resulting in the migration of lipopolysaccharide(LPS)to other tissues.AIM To evaluate the chronic effects(at 10 and 16 wk)of a high-fat diet(HFD)(with 50%energy as fat)on the phylogenetic gut microbiota distribution and intestinal barrier structure and protection in C57BL/6 mice.METHODS Forty adult male mice were divided into four nutritional groups,where the letters refer to the type of diet(control and HFD or HF)and the numbers refer to the period(in weeks)of diet administration:Control diet for 10 wk,HFD for 10 wk,control diet for 16 wk,and HFD for 16 wk.After sacrifice,biochemical,molecular,and stereological analyses were performed.RESULTS The HF groups were overweight,had gut dysbiosis,had a progressive decrease in occludin immunostaining,and had increased LPS concentrations.Dietary progression reduced the number of goblet cells per large intestine area and Mucin2 expression in the HF16 group,consistent with a completely disarranged intestinal ultrastructure after 16 wk of HFD intake.CONCLUSION Chronic HFD intake causes overweight,gut dysbiosis,and morphological and functional alterations of the intestinal barrier after 10 or 16 wk.Time-dependent reductions in goblet cell numerical density and mucus production have emerged as targets for countering obesity-driven intestinal damage. 展开更多
关键词 High-fat diet INTESTINE ULTRASTRUCTURE Goblet cells Gut microbiota
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Structural Features of Nuclei in Leaf Mesophyll Cells of Salt-Tolerant Artemisia marschalliana
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作者 Galina Semenova 《CellBio》 2024年第1期1-6,共6页
All nuclei in mesophyll cells of Artemisia marschalliana are located in vacuoles and occupy up to 90% of their volume. The ultrastructural organization of chromatin in nuclei shows different degrees of its decondensat... All nuclei in mesophyll cells of Artemisia marschalliana are located in vacuoles and occupy up to 90% of their volume. The ultrastructural organization of chromatin in nuclei shows different degrees of its decondensation, up to complete separation of DNA from histones. It is possible that the separation of DNA from histones enables Artemisia to grow in soils with high salinity. 展开更多
关键词 Meso- and Ultrastructure of Mesophyll Decondensation of Nuclear Chromatin Artemisia marschalliana
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Physiology and Ultrastructure of Azolla imbricata as Affected by Hg 2+ and Cd 2+ Toxicity 被引量:27
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作者 施国新 徐勤松 +5 位作者 解凯彬 徐楠 张小兰 曾晓敏 周红卫 朱蕾 《Acta Botanica Sinica》 CSCD 2003年第4期437-444,共8页
The toxic effects of different gradient concentrations of Hg2+ and Cd2+ on chlorophyll content, chlorophyll a/b value, photosynthetic O-2 evolution, respiration rate, anti-oxidase system (superoxide dismulase (SOD), c... The toxic effects of different gradient concentrations of Hg2+ and Cd2+ on chlorophyll content, chlorophyll a/b value, photosynthetic O-2 evolution, respiration rate, anti-oxidase system (superoxide dismulase (SOD), catalase (CAT), peroxidase (POD)) and ultrastructure of the cells of Azolla imbricata (Roxb.) Nakai were studied. The results showed that with Hg2+ and Cd2+ increase, chlorophyll content and chlorophyll a/b value, photosynthetic O-2 evolution decreased drastically; respiration rate peaked at 2 mg/L pollutant and declined afterwards. The activities of SOD, CAT and POD increased first and decreased afterwards except the activity of POD, which decreased with the increasing of Cd2+ concentration. Ultrastructural observation showed that the extent of ultrastructural damage was much more serious with higher pollutant concentration and longer time of stress. This resulted in swelling of chloroplast, disruption and disappearance of chloroplast membrane and disintegration of chloroplasts; swelling of cristae of mitochondria, deformation and vacuolization of mitochondria; condensation of chromatin in nucleus, dispersion of nucleolus and disruption of nuclear membrane. The experimental results showed: (1) Hg2+ and Cd2+ pollution not only destroyed physiological activities, but also caused irreversible damage to its ultrastructure, thus leading the cells to death; (2) With increase in the stress of Hg2+ and Cd2+, ultrastructural damage was related to the changes of plant physiology; (3) The toxic symptoms of plant showed an evident correlation between dose and effect; (4) The toxicity of Cd2+ on A. imbricata is heavier than that of Hg2+ under the same treatment time and concentration. The lethal concentration of Hg2+ to A. imbricata ranged from 3.5 to 4 mg/L, and that of Cd2+ ranged from 3 to 3.5 mg/L. The damage of cell ultrastructure on Anabaena azollae Strasburger was observed. The results indicated that tolerance of Azolla imbricata for Hg2+ and Cd2+ was higher than that of A. imbricata. 展开更多
关键词 Azolla imbricata Hg2+ Cd2+ PHYSIOLOGY ULTRASTRUCTURE
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Ultrastructural Study of Secondary Wall Formation in the Stem Fiber of Phyllostachys pubescens 被引量:22
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作者 贺新强 王幼群 +1 位作者 胡玉熹 林金星 《Acta Botanica Sinica》 CSCD 2000年第10期1003-1008,共6页
Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing... Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing ribosomes, mitochondria and Golgi bodies in the dense cytoplasm. During the wall thickening, the number of rough endoplasmic reticulum and Golgi bodies increased apparently. There were two kinds of Golgi vesicles, together with the ones from endoplasmic reticulum formed transport vesicles. Many microtubules were arranged parallel to the long axis of the cell adjacent to the plasmalemma. Along with the further development of fiber, polylamellate structure of the secondary wall appeared, with concurrent agglutination of chromatin in the nucleus, swelling and disintegration of organelles, while cortical microtubules were still arranged neatly against the inner side of plasmalemma. Lomasomes could be observed between the wall and plasmalemma. The results indicated that the organelles, such as Golgi bodies together with small vesicles, rough endoplasmic reticulum and lomasomes, played the key role in the thickening and lignification of the secondary wall of bamboo fiber, though cortical microtubules were correlative with the process as well. 展开更多
关键词 secondary wall formation ULTRASTRUCTURE ORGANELLE FIBER Phyllostachys pubescens
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Study on Development Rule of Muscle Fiber in Different Duck Breeds 被引量:14
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作者 廖菁 常国斌 +4 位作者 徐琪 张依裕 张海波 周琼 陈国宏 《Agricultural Science & Technology》 CAS 2009年第5期107-109,共3页
[Objective] The aim of this study was to investigate the development rule of muscle fiber in different duck breeds during various developmental stages. [Method] Cherry valley duck, Jinding duck, White muscory duck and... [Objective] The aim of this study was to investigate the development rule of muscle fiber in different duck breeds during various developmental stages. [Method] Cherry valley duck, Jinding duck, White muscory duck and Suma duck ( Cherry valley duck ♂ × Jinding duck ♀ ) were fed for 10 weeks to observe the ultrastructure of muscle fiber by electron microscope, and the myofibril diameter and sarcomere length were also determined. [Result] The myofibril diameter increased with ages. Sarcomere length and myofibril diameter did not change significantly with the increasing ages (P〉0.05). The myofibril diameter of White muscory duck and Jinding duck were thicker, while that of Cherry valley cluck and Suma duck were thinner. Moreover, the sarcomere length of Suma duck and White muscory duck were longer, while that of Cherry valley duck and Jinding duck were shorter. Thus, the basic characteristics of ultrastructure of muscle fiber were consistent in these duck breeds.[Conclusion] The results have an important meaning for duck breeding. 展开更多
关键词 DUCK Muscle fiber ULTRASTRUCTURE Development rule
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Ovule Development, Formation of Pollination Drop and Pollination Process in Taxus chinensis (Taxaceae) 被引量:11
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作者 邢树平 陈祖铿 +2 位作者 胡玉熹 周馥 林金星 《Acta Botanica Sinica》 CSCD 2000年第2期126-132,共7页
Pollen morphology and hydration, ovule development, formation of pollination drop and the pollination process of Taxus chinensis (Pilg.) Rehd were investigated in detail. The results showed that mature pollen was ... Pollen morphology and hydration, ovule development, formation of pollination drop and the pollination process of Taxus chinensis (Pilg.) Rehd were investigated in detail. The results showed that mature pollen was one_celled, irregular in shape, nonsaccate, and the surface was covered with orbicules. When pollen became hydrated, the intine swelled and the exine bursted. The exine usually remained on the surface of water or on the pollination drop all the time, while the rest portion of the pollen sank into the drop of water or the pollination drop. In the late August, the down_curved female buds could be observed in the field trees. The downturning of the female buds was an characteristic feature discriminating from the vegetative buds. At this stage ovular primordium was present in the female bud with a dome_shaped nucellar primordium encircled by a rudimentary integument. The integument grew fast and overgrew the nucellus. In the March of the following year, the ovule formed a micropylar canal about 1?000 μm in length, 200-300 μm in width. Except the micropyle, the other part of the ovule was enclosed by 20-25 scales. During the early stage of the ovule development, the nucellar surface clearly showed cell configuration; but a membrane_like structure covering the nucellar apex appeared in the late stage of the ovule development, and subsequently broke down with nucellar cell disintegration before pollen shedding. The disintegrated cell products might partake in the formation of the pollination drop. Before and during pollination, the nucellar cells contained abundant mitochondria, endospermic reticulum and dictysomes with vesicles; the plasma membrane was undulated and there was no accumulation of electron_dense substances in the pericytoplasm. Pollination drops usually occurred at night, and disappeared by noon in the field tree. 15 days before pollination, the in vitro ovules from the field trees already had the capability of producing pollination drops, which could last for 4-5 days indoors. However, after these drops received pollen, they did not withdraw noticeably compared with the unpollinated ones. The retraction of the pollination drop was presumed not to be a nonmetabolic outcome but rather a result of evaporation. 展开更多
关键词 Taxus chinensis POLLEN ovule development nucellar ultrastructure pollination drop
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Nerve Terminal Types of Sinus Gland and Neurosecretory Cell Types of X-organ in Crab Eriocheir sinensis 被引量:7
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作者 韦荣编 邱高峰 楼允东 《Zoological Research》 CAS CSCD 北大核心 2002年第3期226-232,T002-T003,共9页
The ultrastructure of the X organ sinus gland complex in sexually immature Chinese mitten crab Eriocheir sinensis was examined under the electron microscope. The sinus gland (SG) is composed primarily of nerve te... The ultrastructure of the X organ sinus gland complex in sexually immature Chinese mitten crab Eriocheir sinensis was examined under the electron microscope. The sinus gland (SG) is composed primarily of nerve terminals and glial cells. The terminal contains a great number of membrane bound granules, mitochondria, rough endoplasmic reticulum and electron lucent vesicles. The profiles of the terminals are sometimes exhibited finger like projections. The X organ (XO) locates at the ventral surface of the medulla terminalis ganglion in the eyestalk, oppositing to SG. According to the features of granule size, shape, electron density and cytoplasm, 6 types of terminals in SG and 7 types of neurosecretory (NS) cells in XO were identified. The release process by exocytosis of the granules in SG was observed and a tentative comparison was made for the granules between different types of terminals and NS cells. It seemed that they had a good correspondence since no change in electron density and just a slight increase of sizes was shown. 展开更多
关键词 Eriocheir sinensis Sinus gland X organ Neurosecretory granule ULTRASTRUCTURE
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Vegetative Storage Proteins in Meliaceae 被引量:7
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作者 田维敏 吴继林 +1 位作者 郝秉中 胡正海 《Acta Botanica Sinica》 CSCD 2002年第2期242-245,共4页
采用光学和电子显微镜技术及SDS_PAGE研究了营养贮藏蛋白质 (VSPs)在楝科树木中的分布和超微结构 ;并采用免疫印迹技术 ,以大叶桃花心木 (SwieteniamacrophyllaKing)的 2 1kDVSP的抗血清检测楝科树木VSPs的免疫相关性。结果表明 ,在桃... 采用光学和电子显微镜技术及SDS_PAGE研究了营养贮藏蛋白质 (VSPs)在楝科树木中的分布和超微结构 ;并采用免疫印迹技术 ,以大叶桃花心木 (SwieteniamacrophyllaKing)的 2 1kDVSP的抗血清检测楝科树木VSPs的免疫相关性。结果表明 ,在桃花心木亚科 (Swietenioideae)的树木中普遍存在VSPs ,但楝亚科 (Melioidae)仅部分属的树木有VSPs而椿亚科 (Cedreloideae)树木没有VSPs。VSPs在同一属树木中的分布是一致的。桃花心木亚科和楝亚科树木之间的VSPs几乎没有免疫相关性 ,但是在桃花心木亚科中 ,VSPs具有相对高的同源性。楝科树木VSPs的超微结构存在一定程度的差异 ,这可能与VSPs的种类不同有关。VSPs的分布。 展开更多
关键词 vegetative storage proteins ULTRASTRUCTURE immuno-correlation MELIACEAE
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Comparison of Photosynthetic Adaptability Between Kobresia humilis and Polygonum viviparum on Qinghai Plateau 被引量:15
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作者 魏捷 余辉 +2 位作者 钟泽璞 匡廷云 贲桂英 《Acta Botanica Sinica》 CSCD 2001年第5期486-489,共4页
The chlorophyll fluorescence parameters of Kobresia humilis Serg. and Polygonum viviparum L. grown at two different altitudes (3?200 m, 3?980 m) were measured and the ultrastructure of chloroplasts were observ... The chlorophyll fluorescence parameters of Kobresia humilis Serg. and Polygonum viviparum L. grown at two different altitudes (3?200 m, 3?980 m) were measured and the ultrastructure of chloroplasts were observed for studying the photosynthetic adaptability of plants to the influences of stress conditions in alpine environment. Rfd _values, the vitality index, in leaves of K. humilis and P.viviparum grown at 3?980 m were higher than those at 3?200 m. The higher ratio of F v/F o and F v/F m in leaves of K. humilis and P.viviparum indicated that the rate of photosynthetic conversion of light energy increased at higher altitude. Ratios of F v/F o and F v/F m and Rfd _values in K.humilis were higher than that in P.viviparum grown at the same altitude. There were more irregular chloroplasts in leaves of both species grown at higher altitude. Many irregular chloroplasts such as swollen thylakoid, deformed chloroplast envelope, were observed in P.viviparum grown at 3?980 m, but few in K. humilis . These results were discussed in relation to the photosynthetic adaptability of alpine plants and the different adaptive competence between K.humilis and P.viviparum . 展开更多
关键词 alpine plants Kobresia humilis Polygonum viviparum chlorophyll fluorescence ultrastructure of chloroplast
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Development and Ultrastructure of the Phloem Ganglion in Bamboo Node 被引量:11
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作者 丁雨龙 樊汝汶 黄金生 《Acta Botanica Sinica》 CSCD 2000年第10期1009-1013,共5页
The development, cytological characters and ultrastructure of phloem ganglion in the nodal region of Phyllostachys edulis (Carr.) H. de Lehaie, a most economically important bamboo, were investigated and the possi... The development, cytological characters and ultrastructure of phloem ganglion in the nodal region of Phyllostachys edulis (Carr.) H. de Lehaie, a most economically important bamboo, were investigated and the possible physiological function of this special structure was proposed. The phloem ganglion derived directly from procambium is situated at the sites where the vascular bundle forks and is present in pairs. The phloem ganglion is spindle_like in appearance and usually consists of 4 to 6 layers. Two kinds of cells in the ganglion could be distinguished. In the middle, there are two layers of filiform cells with pointed ends so that there are no normal sieve plates. Nevertheless, there are many pits on the lateral wall of the filiform cells. The other type of cells located at both ends of the spindle which possess an intermediate form between the filiform cell and the normal sieve tube. The walls of these cells towards the filiform cells are strongly convex forming a special sieve plate. Ultrastructure study showed that cells in the ganglion are connected by enriched plasmodesma. During early differentiation, the paramural body and the ingrowth of cell wall could be observed. It indicates that the cells of phloem ganglion have the character of transfer cells. The organelles in the mature cells are mainly plastids with abundant accumulation of proteins of crystalline structure. The above_mentioned results suggest that the physiological function of the phloem ganglion is closely related with substance transport. 展开更多
关键词 phloem ganglion individual development ULTRASTRUCTURE physiological function
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Ultrastructure of Epidermis and Flesh of the Developing Apple Fruit 被引量:16
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作者 彭宜本 张大鹏 《Acta Botanica Sinica》 CSCD 2000年第8期794-802,共9页
The ultrastructure of the epidermis and flesh of apple ( Malus domestica Borkh cv. Red Fuji) fruit was systematically observed during the fruit development via transmission electron microscopy. The results showed t... The ultrastructure of the epidermis and flesh of apple ( Malus domestica Borkh cv. Red Fuji) fruit was systematically observed during the fruit development via transmission electron microscopy. The results showed that, in spite of the ultrastructural changes in many aspects of the developing fruit epidermal cells, it remained almost unchanged throughout the whole developmental process that the cytoplasm was filled with numerous endoplasmic reticula (ER). Most of these endoplasmic reticula were tube_like and rough_ER with enlarged cisterna from which many vesicles were produced. Some of the vesicles were shown to merge into vacuole. Some dynamic Golgi bodies were also found. All the ultrastructural characteristics showed that the epidermal cells have the features of excretory cells. The ultrastructure of the fruit flesh cells at the young fruit stage were shown to be metabolically active, characterized by the presence of numerous clustered plasmodesmata, cisterna enlarged_ and rough_ER filling the cytoplasm, plenty of vesicles and Golgi bodies, indicating their dynamic cellular transport function. Some giant_circular rough_ERs were found. All the ultrastructural features at this early developmental stage should be closely associated with the enlargement of the young fruit. At the rapid growing phase of the fruit the main changes were characterized by: the starch grain_filled amyloplasts, furcating of the single orifice of plasmodesmata, and the cytoplasm enrichment of both the Golgi body_formed vesicles and other vesicles. These features correspond well with those of a photoassimilate sink_cell. An ultrastructural degeneration phenomenon was observed at the fruit ripening stage, but the mitochondria and plasmalemma still remained intact, which might be related to the continuous development of fruit quality during the fruit ripening. 展开更多
关键词 APPLE FRUIT EPIDERMIS FLESH ULTRASTRUCTURE fruit development
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