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Ultrastructure and key identification points of fossilized Os Draconis in traditional Chinese medicine
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作者 Dong-Han Bai Zi Xing +5 位作者 Zi-Hao Zhang Zhi-Jie Zhang Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Lu Luo 《Traditional Medicine Research》 2026年第1期39-46,共8页
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa... Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications. 展开更多
关键词 Os Draconis ultrastructure identification points electron probe polarized light microscope
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Effects of different light intensity on the growth,physiological and biochemical properties,and stomatal ultrastructure of Rhododendron micranthum saplings
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作者 Yan Zhao Duo Xu +6 位作者 Zhihui Yu Jiaqi Huang Jiahui Li Yang Sun Xuhe Wang Qingtao Wang Xiaowei Wang 《Journal of Forestry Research》 2025年第3期171-188,共18页
Rhododendron micranthum Turcz.is a shrub esteemed for its ornamental and medicinal attributes within the Changbai Mountain range of China.We selected 3-year saplings and subjected them to four distinct light condi-tio... Rhododendron micranthum Turcz.is a shrub esteemed for its ornamental and medicinal attributes within the Changbai Mountain range of China.We selected 3-year saplings and subjected them to four distinct light condi-tions:full light(CK),70%light(L1),50%light(L2),and 30%light(L3)to investigate variations in morphology,photosynthetic responses,stomatal ultrastructure as well as the mechanisms through which these saplings adapt to differing lighting environments.The results indicate that L2 leaves exhibit significantly greater length,width,and petiole development compared to other treatments across varying intensities.Over time,chlorophyll content and PSII levels in L2-treated saplings surpass those observed in other treatments;Proline(PRO),malondialdehyde(MDA),and soluble protein(SP)contents are markedly lower under L2 treatment.Catalase(CAT)and superoxide dismutase(SOD)demonstrate significant correlations across various light con-ditions but respond differently among treatments,indicat-ing distinct species sensitivities to light intensity while both contribute to environmental stress resistance mechanisms.Findings reveal that R.micranthum saplings at 50%light intensity benefit from enhanced protection via antioxidant enzymes,and shading reduces osmotic adjustment sub-stances yet increases chlorophyll content.Stomatal length/width along with conductance rates and net photosynthesis rates for L2 exceed those of CK,suggesting an improved photosynthetic structure conducive to efficient photosynthe-sis under this condition.Thus,moderate shading represents optimal growth at 50%illumination,a critical factor promot-ing sapling development.This research elucidates the ideal environment for R.micranthum adaptation to varying light conditions supporting future conservation initiatives. 展开更多
关键词 Light intensity Eco-physiological characteristics Stomatal ultrastructure Rhododendron micranthum Turcz.
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Ultrastructure and Polyene Pigments of Giant Triton Snail Charonia tritonis(Gastropoda)Shells from the South China Sea
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作者 XU Meng LIU Wenguang LU Jianguo 《Journal of Ocean University of China》 2025年第4期1039-1044,共6页
The giant triton snail Charonia tritonis is a marine large carnivorous gastropoda inhabiting in the Indo-Pacific Ocean.Their splendid and highly organized Charonia tritonis shells are attractive;however few studies ha... The giant triton snail Charonia tritonis is a marine large carnivorous gastropoda inhabiting in the Indo-Pacific Ocean.Their splendid and highly organized Charonia tritonis shells are attractive;however few studies have been conducted on shell ultra-structure and pigmentation.The arrangements of crossed-lamellar structures were distinctive for the giant triton snail shell,showing three layers of mineral structures in the cross-section.The 1st-order and 2nd-order lamellae of the shell were around 10-20μm and the crystals in outer layers intersected at right angles in this species.They were identified as aragonite crystals by Raman scattering,and granular organic matrix were attached to the aragonite mineral phase closely.Furthermore,the dominant Raman spectra from polyene pigments in the shell were characterized at wavenumbers of 1123 cm^(-1)and 1504 cm^(-1),assigned to stretching vibrations of carbon-carbon single(C-C)and double(C=C)bonds,and the polyene chain was confirmed with 11-12 C-C bonds and 12-13 conju-gated C=C bonds.The research will lay a foundation for exploring the relationship between the calcareous shell and the formation of shell color in the giant triton snail. 展开更多
关键词 giant triton snail Charonia tritonis shell ultrastructure Raman scattering polyene pigments
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鸡蛋暗斑及其营养调控措施的研究进展
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作者 邵丹 王强 童海兵 《动物营养学报》 北大核心 2026年第2期801-809,共9页
暗斑是鸡蛋中常见的外观缺陷,是鸡蛋产出后在一定温湿度、时间等条件下在蛋壳上呈现出的一种浅褐色斑点。蛋壳暗斑十分影响鸡蛋的美观,削减消费者的购买欲望,降低了养殖企业的经济效益。随着消费者对食品安全意识的增强和对蛋品质量要... 暗斑是鸡蛋中常见的外观缺陷,是鸡蛋产出后在一定温湿度、时间等条件下在蛋壳上呈现出的一种浅褐色斑点。蛋壳暗斑十分影响鸡蛋的美观,削减消费者的购买欲望,降低了养殖企业的经济效益。随着消费者对食品安全意识的增强和对蛋品质量要求的提高,暗斑成因与预防的研究愈发关键。本文综述了暗斑的成因、变化规律、评价方法、对蛋品质的影响及近年来降低暗斑发生率的营养调控措施,旨在为降低鸡蛋暗斑发生技术的研发提供参考。 展开更多
关键词 鸡蛋 暗斑 营养调控 超微结构
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代谢性脂肪肝炎小鼠肝窦内皮细胞窗孔的超微结构病变研究
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作者 刘畅 郭宏博 +2 位作者 甘雅玲 聂广军 赵颖 《电子显微学报》 北大核心 2026年第1期53-58,共6页
代谢性脂肪肝炎(metabolic dysfunction-associated steatohepatitis,MASH)是代谢综合征在肝脏的核心病理表现,其特征以肝细胞脂质沉积、炎性浸润及纤维沉积为主。肝窦内皮细胞(liver sinusoidal endothelial cells,LSECs)特有的窗孔结... 代谢性脂肪肝炎(metabolic dysfunction-associated steatohepatitis,MASH)是代谢综合征在肝脏的核心病理表现,其特征以肝细胞脂质沉积、炎性浸润及纤维沉积为主。肝窦内皮细胞(liver sinusoidal endothelial cells,LSECs)特有的窗孔结构(fenestrae)是维持肝窦通透性及物质交换的形态学基础,但其重构与MASH病理改变的关联尚未完全阐明。本研究基于MASH小鼠模型,利用扫描电子显微镜(scanning electron microscope,SEM),系统观察了LSECs窗孔超微结构的演变规律。结果表明,伴随着MASH病程进展,其窗孔发生进行性破坏:孔隙率大幅降低、孔径减小,窗孔异质性极化、闭合及类似“环形山”样结构等病变。以上研究结果揭示,伴随肝脏病变的发生和进展,LSECs出现了“去窗孔化”和复杂的结构改变,强调了肝窦功能障碍在疾病进程中的重要作用。 展开更多
关键词 超微结构 肝脏 肝窦内皮细胞 窗孔 扫描电子显微镜
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Ultrastructure Features of Sperm Cell in Amaryllis vittata
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作者 蔡雪 魏令波 《Developmental and Reproductive Biology》 1996年第1期49-54,T001-T002,共8页
Ultrastructure of sperm cells in pollen tube of Amaryllis vittata Ait. has been investigated in details by electron microscopy ,with particular emphasis on the organization and distribution of microtubules.The two new... Ultrastructure of sperm cells in pollen tube of Amaryllis vittata Ait. has been investigated in details by electron microscopy ,with particular emphasis on the organization and distribution of microtubules.The two newly formed sperm cells are arranged in tandem and sometimes in transverse at the right angle to the long axis of the pollen tube.Thevegetative nucleus is ahead and closely associated with the two sperm cells in all examined pollen tubes. The microtubules are distributed in the region between the common cell wall and the proximity of the sperm nucleus,they are singles and dispersed with mainly orientation of longitudinal and oblique,forming a loose bucket-like structure as a whole.In late stage of development,all of the microtubule array longitudinally and enclose the sperm nucleus.This configuration is very similar to the basket-like structure of microtubule in the generative cell. These results show that the organization and distribution of microtubules in the sperm cells are dynamic during cell development. 展开更多
关键词 Amaryllis vittata Sperm cell MICROTUBULE ultrastructure.
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基于改进U-Mamba网络的聚酯纤维超微结构分割算法
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作者 周宇 隗兵 +2 位作者 郝矿荣 皋磊 王华平 《纺织学报》 北大核心 2026年第1期72-79,共8页
针对工业生产中聚酯纤维超微结构中的团聚效应对产品的颜色均匀性、机械性能均匀性及光泽度等性能的负面影响这一问题,提出一种基于改进U-Mamba的聚酯纤维超微结构分割算法。首先利用扫描电子显微镜采集聚酯纤维超微结构中团聚粒子分布... 针对工业生产中聚酯纤维超微结构中的团聚效应对产品的颜色均匀性、机械性能均匀性及光泽度等性能的负面影响这一问题,提出一种基于改进U-Mamba的聚酯纤维超微结构分割算法。首先利用扫描电子显微镜采集聚酯纤维超微结构中团聚粒子分布的高分辨率图像并建立对应的超微结构数据集以评估模型性能,使用结合边缘检测算法的预训练神经网络对纤维图像进行去噪、滤波以及自动着色处理,通过设计高阶视觉状态空间模块和多尺度信息融合模块,改进后的U-Mamba深度网络模型能够准确识别并分割超微结构中团聚体。实验结果表明:在超微结构数据集下,该算法对比其它经典算法具有较高的分割准确性,其交并比达到78.9%,平均准确率达到96.1%,能够满足工业生产中机器视觉技术在高功能纤维超微结构分析中的应用需求。 展开更多
关键词 聚酯纤维 超微结构分布 机器视觉 U-Mamba算法 语义分割
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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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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:17
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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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Ultrastructure of the Multicellular Nodules in Hypericum perforatum Leaves 被引量:4
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作者 刘文哲 吕洪飞 胡正海 《Acta Botanica Sinica》 CSCD 2002年第6期649-656,共8页
With the development of the multicellular nodules in the leaves of Hypericum per plastids increased both in number and volume, and some plastids degenerated and were surrounded by dark tubular elements and vesicles. S... With the development of the multicellular nodules in the leaves of Hypericum per plastids increased both in number and volume, and some plastids degenerated and were surrounded by dark tubular elements and vesicles. Some vesicles fused with vacuoles and secreted substances into vacuoles. There are many multivesicles, multimembrane structures and osmiophilic droplets in vacuoles of nodule cells. Meanwhile, dictyosome secreted vesicles into the vacuoles. However, there is a large central vacuole completely filled with secretory materials (hypericin) in matured multicellular nodules. This suggests that the osmiophilic droplets may be a precursor of hypericin originated from the degenerated plastids. There were abundant endoplasmic reticulums and dictyosomes between the plastids and osmiophilic droplets, suggesting that they may be involved in the synthesis and/or transport of the precursor of hypericin. 展开更多
关键词 Hypericum perforatum multicellular nodules ultrastructure HYPERICIN
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Ultrastructure of Oogenesis in Osmunda cinnamomea var. asiatica 被引量:4
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作者 包文美 曹建国 戴绍军 《Acta Botanica Sinica》 CSCD 2003年第7期843-851,共9页
The ultrastructure of oogenesis in the fern Osmunda cinnamomea L. var. asiatica Fernald has been studied by electron microscopy. During oogenesis, numerous vesicles not only moved towards the periphery, but also were ... The ultrastructure of oogenesis in the fern Osmunda cinnamomea L. var. asiatica Fernald has been studied by electron microscopy. During oogenesis, numerous vesicles not only moved towards the periphery, but also were arranged in line along the inside of plasmalemma, and in addition aggregated outside the plasmalemma by exocytosis. They released or excreted osmiophilic material. It was observed that a few vesicles containing lamellar osmiophilic material situated closely along the plasmalemma, seemed to break open. Simultaneously, a separation cavity between egg cell and archegonium wall formed. Its width was broader than the other advanced ferns reported previously, and an extra egg membrane occurred outside around the plasmalemma of the egg, its thickness being greater than in Pteridium and Dryopteris. Amyloplasts around the nucleus were filled with large triangular semicircular or subelliptical starch grains, but as the egg matured they progressively decreased. Nucleus was large and flattened, and paired membrane in two to three couples laid within the nucleus, close and parallel to the nuclear membrane. No nuclear evagination was observed. Mitochondria seemed to have been undeveloped, but finally recovered normally. 展开更多
关键词 ultrastructure OOGENESIS Osmunda cinnamomea var. asiatica FERN
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Ultrastructure of the Blepharoplast and the Multilayered Structure in Spermatogenesis in Osmunda cinnamomea var. asiatica 被引量:3
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作者 曹建国 包文美 戴绍军 《Acta Botanica Sinica》 CSCD 2003年第7期832-842,共11页
The ultrastructure of the blepharoplast and the multilayered structure (MLS) in the fern Osmunda cinnamomea var. asiatica Fernald have been studied by electron microscopy with respect to spermatogenesis. The blepharop... The ultrastructure of the blepharoplast and the multilayered structure (MLS) in the fern Osmunda cinnamomea var. asiatica Fernald have been studied by electron microscopy with respect to spermatogenesis. The blepharoplast appears in the young spermatid. The differentiating blepharoplast is approximately a spherical body, which is composed of densely stained granular material in the center and some cylinders outside of it. The differentiated blepharoplast is also a sphere, but without the densely stained material in the center, consisting of scattered or radially arranged cylinders. The MLS seen in the spermatid lies between the basal bodies and the giant mitochondrion. In the early developmental stage, the MLS only consists of lamellar layers, each of which runs parallel to one another and forms a strip. In the mid stage, the MLS is composed of the microtubular ribbon (MTr), the lamellar layers and a layer of plaque. In the late stage, the MLS forms accessory band, osmiophilic crest and a layer of osmiophilic material. The MTr grows out from the MLS and extends along the surface of the nucleus to unite with the nuclear envelope in a complex. The basal body coming from the cylinder produces the axoneme of the flagella in the distal end and the wedge-shaped structure in the proximal end, respectively. In the present study, the ultrastructural features of blepharoplast and the MLS of the protoleptosporangiopsida fern, O. cinnamomea var. asiatica, have been described and compared with those of other kinds of pteridophytes in detail. The lamellar layers appearing before the formation of the MTr was found and reported for the first time. 展开更多
关键词 Osmunda cinnamomea var. asiatica blepharoplast multilayered structure ultrastructure
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ULTRASTRUCTURE OF THE VEGETATIVE CELLS OF NOSTOC FLAGELLIFORME PREPARED WITH HIGH PRESSURE FREEZING AND FREEZE SUBSTITUTION TECHNIQUE 被引量:8
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作者 祝建 王俊 +1 位作者 华振基 马丁.米勒 《Acta Botanica Sinica》 CSCD 1998年第10期901-905,共5页
The ultrastructure of the vegetative cells of Nostoc flagelliforme Born. et Flah. was investigated with high pressure freezing and freeze substitution technique and compared with the results obtained by using conv... The ultrastructure of the vegetative cells of Nostoc flagelliforme Born. et Flah. was investigated with high pressure freezing and freeze substitution technique and compared with the results obtained by using conventional preparation methods. During the processes of chemical fixation, dehydration and embedding, the cell structures might be more artificially modified than that obtained from high pressure freezing and freeze substitution. With the present method, the sheath of N. flagelliforme could be well penetrated and no extra big space could exist between the cell and the sheath. The cell protoplasm rarely shrinked. Some fine structures of cell inclusions and unit membranes became visualized. Many bacteria were harbored in the sheath. In addition, the presence of big vacuoles in the cell of N. flagelliforme as well as the presence of bacteria in the sheath shown in the present preparation for cyanobacteria has not been described so far in the literature. 展开更多
关键词 ultrastructure Nostoc flagelliforme Vegetative cell High pressure freezing Freeze substitution
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Effects of CO_2 Enrichment on Microstructure and Ultrastructure of Two Species of Freshwater Green Algae 被引量:4
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作者 夏建荣 高坤山 《Acta Botanica Sinica》 CSCD 2002年第5期527-531,共5页
order to investigate the morphological response of freshwater green algae to elevated CO2 concentration, Chlamydomonas reinhardtii Dang and Scenedesmus obliquus Kutz were cultured with enriched CO2, and their microstr... order to investigate the morphological response of freshwater green algae to elevated CO2 concentration, Chlamydomonas reinhardtii Dang and Scenedesmus obliquus Kutz were cultured with enriched CO2, and their microstructure and ultrastructure were examined by microscopy and electron microscopy. The effect of CO2 enrichment to 186 mumol/L, was insignificant on the shape and size of C. reinhardtii, but significant in reducing the volume of S. obliquus. High-CO2 increased the amount of chloroplast. The pyrenoids occurred in low-CO2-grown cells but not in high-CO2-grown ones and more starch granules were observed in the former. 展开更多
关键词 Chlamydomonas reinhardtii CO2 MICROSTRUCTURE PYRENOID Scenedesmus obliquus starch granules ultrastructure
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Evidence of Ultrastructure and Physiology of F-actin as Component of Plasmodesmata 被引量:2
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作者 王冬梅 王学臣 张伟成 《Acta Botanica Sinica》 CSCD 2002年第11期1278-1285,共8页
The characters and ultrastructure of the intercellular connection were revealed in the outer epidermis of the garlic clove sheath by means of fluorescent probe TRITC_Phalloidin (TRITC_Ph) labeling combined with confoc... The characters and ultrastructure of the intercellular connection were revealed in the outer epidermis of the garlic clove sheath by means of fluorescent probe TRITC_Phalloidin (TRITC_Ph) labeling combined with confocal laser scanning microscopy (CLSM), immuno_gold labeling and transmission electron microscopy. These results show that transcellular channel is a complex of rod_like cytoplasm channel and grouped plasmodesmata (PDs) in pit. The former remains a portion of the cell protoplast. The diameter of PD is normally 60-70 nm. The PDs are the real intercellular symplasmic connections of the cells. The transcellular fibers labeled with the TRITC_Ph obviously become narrow in the primary pit fields, which is the same as the characters observed under the electron microscope. The bright fluorescent spot in the primary wall reflects the grouped PDs in pit, and hence the presence of F_actin in the PDs can be confirmed. In immuno_gold labeling experiment, a lot of gold particles were massively distributed in the rod_like cytoplasm channel and grouped PDs. The result provides effective support that these fluorescent filaments possibly are the existing form of F_actin. 展开更多
关键词 PLASMODESMATA F_actin confocal laser scanning microscopy (CLSM) ultrastructure Allium sativum
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Effects of Doubled_CO_2 Concentration on Ultrastructure, Supramolecular Architecture and Spectral Characteristics of Chloroplasts from Wheat 被引量:1
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作者 左宝玉 张泉 +2 位作者 姜桂珍 白克智 匡廷云 《Acta Botanica Sinica》 CSCD 2002年第8期908-912,共5页
Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architect... Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architecture, absorption spectrum and low temperature (77 K) fluorescence emission spectrum of the chloroplasts from wheat leaves. The results were briefly summarized as follows: (1) The wheat leaves possessed normally developed chloroplasts with intact grana and stroma thylakoid membranes; The grana intertwined with stroma thylakoid membranes and increased slightly in stacking degree and the width of granum, in spite of more accumulated starch grains within the chloroplasts than those in control; (2) The particle density in the stacked region of the endoplasmic fracture face (EFs) and protoplasmic fracture face (PFs) and in the unstacked region the endoplasmic fracture face (EFu) and the protoplasmic fracture face (PFu) was significantly higher than that of control. Furthermore, in some cases many more particles on EFs faces of thylakoid membranes appeared as a paracrystalline particle array; (3) The variations in the structure of chloroplasts were consistent with the absorption spectra and the low temperature (77 K) fluorescence emission spectra of the chloroplasts developed under the doubled_CO 2 concentration. Results indicate that the capability of light energy absorption of chloroplasts and regulative capability of excitation energy distribution between PSⅡ and PSⅠ were raised by doubled_CO 2 concentration. This is very favorable for final productivity of wheat. 展开更多
关键词 chloroplast wheat ( Triticum aestivum ) doubled_CO 2 concentration ultrastructure and supramolecular architecture absorption spectra low temperature (77 K) fluorescence emission spectra
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Seasonal Changes in the Ultrastructure of the Vascular Cambium in Shoots of Populus tomentosa 被引量:1
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作者 殷亚方 姜笑梅 崔克明 《Acta Botanica Sinica》 CSCD 2002年第11期1268-1277,共10页
Wood is the product of cambial activity in trees, and the seasonal activity style of cambium directly influences wood biomass production, structures and properties. The seasonal changes in the ultrastructure of the va... Wood is the product of cambial activity in trees, and the seasonal activity style of cambium directly influences wood biomass production, structures and properties. The seasonal changes in the ultrastructure of the vascular cambium activity of Populus tonientosa Carr. planted in Beijing area were examined in shoot tissues collected during 15 months by means of transmission electron microscopy. Before xylem mother cells reactivated completely, the dividing fusiform cells in cambium and new phloem cells had appeared at the same time. The initiation of cambial activity may be related to the bud sprouting and the young leaf growth in shoots. More details about the ultrastructural changes of cambial cells at the onset of cambial activity have been gained. When the large vacuole in active cambial cells divided into smaller ones during the dormant phase, proteinaceous material that disappeared in active cambial cells refilled many of these small vactioles. In addition, lipid droplets and starch granules had the same cycles as proteinaceous material. The plasmalemma invaginations of fusiform cells were observed not only in active phase but also in dormancy. The endomembrane system consisting of nuclear membrane, endoplasmic reticulum (ER), dictyosomes and their secretory vesicles, changed in form and distribution at different phases during a cycle and performed important roles at the onset of active cambium and during the wall formation process of secondary xylem cells. The tangential walls remained relatively thin throughout the year but the radial walls thickened markedly when the cambium was dormant. During the transition from dormancy to activity, a partial autolysis occurred in the radial walls of the cambial cells, especially at the cell wall junctions. A notable feature of the cells at the onset of cambial activity was the thinning of the radial walls. 展开更多
关键词 vascular cambium ultrastructure endomembrane system cell wall seasonal changes Populus tomentosa
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THE SECRETORY STIGMAS IN POPULUS: DEVELOPMENT, CYTOCHEMISTRY, ULTRASTRUCTURE AND THEIR RELATION TO INTERSECTIONAL INCOMPATIBILITY * 被引量:1
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作者 李文钿 孙福生 +1 位作者 成小飞 朱彤 《Acta Botanica Sinica》 CSCD 1995年第7期514-521,共8页
The stigmas of five species, Populus euphratica Oliv., P. alba L., P. simonii Carr., P. lasiocarpa Oliv. and P. nigra L. have been studied. Scanning electron microscopy re veals that exudates are present in the ... The stigmas of five species, Populus euphratica Oliv., P. alba L., P. simonii Carr., P. lasiocarpa Oliv. and P. nigra L. have been studied. Scanning electron microscopy re veals that exudates are present in the intercellular spaces, in the clefts between the multicel lular papillae and on the receptive surface. Release and movement of exudates can be visual ized when the fresh stigmas are stained with sudan Ⅲ and auramine O. Paraffin and semi thin resin sections of stigmas after glutaraldehyde osmium fixation evidence the lipidic nature of the exudates. Transmission electron microscopy reveals the glandular features of the stigmatic papillae cells, such as abundance of rough and smooth endoplasmic reticulum, polyribosomes, and well developed dictyosomes with secretory vesicles. Pellicle and epicuticular lamellate layers which have been considered as typical features of the dry type stigmas are also present in the species where stigmas appear extremely wet. It is concluded that stigmas in all of the five species are secretory at the receptive stage. Well developed generative and sperm cells were observed in the pollen tubes penetrating through the deep layers of the stigmatic tissue in the reciprocal crosses between P. euphratica and P. simonii, which indicated that there is no significant barrier in the stigma. 展开更多
关键词 Secretory stigma POPULUS ultrastructure CYTOCHEMISTRY INCOMPATIBILITY
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THE EFFECT OF ACTIVE COMPONENTS OF LYCIUM BARBARUM AND GARLIC (LB-GO) ON THE SYNTHESIS OF DNA AND ULTRASTRUCTURE OF U_(14) CERVIX CANCER CELLS IN MICE 被引量:1
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作者 胡庆和 高天顺 +4 位作者 赵承军 张焱 谢锦玉 沈联慈 刘铭福 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1994年第4期266-273,共8页
Mice, inoculated with U_(14) ascitic type cervix cancer cells, were administered with effective components of Lycium barbarum (LB) and garlic (GO).On the 4th day after i.p.administration, general condition of the anim... Mice, inoculated with U_(14) ascitic type cervix cancer cells, were administered with effective components of Lycium barbarum (LB) and garlic (GO).On the 4th day after i.p.administration, general condition of the animals were found improved.Examination of ascitic fluid revealed damage of the cancer cells, blanching of fluorescence staining of DNA and RNA, and the cancer cells besieged by large numbers of macrophages and leucocytes. Flow cell metric (FCM) analysis found: accumulation of cells of G_1 stage. Ultrastructure study disclosed: swelling of mitochondria in cytoplasm and damage of mitochondrial crests even with cavity formation, enlargement and degranulation of rough ER. It seemed the effect of LBGO was affirmable. It was postulated that macrophages,being activated by LB, came in close contact with the cancer cells giving rise to carcinolysis. In addition to the direct but transient killing effect of GO, the anti-cancer results could be greatly enhanced. 展开更多
关键词 Lycium barbarum GARLIC U_(14) Cervix cancer cell DNA synthesis ultrastructure.
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