12种百合属植物花粉形态扫描电镜观察

应用扫描电镜对百合属4个野生种和8个栽培品种的花粉形态进行了观察和比较。结果表明,12个百合品种中4个野生种(细叶百合、兰州百合、卷丹和大花卷丹)和4个栽培种(布鲁赛尔、普瑞头、多安娜和红骑士)的花粉粒形状为椭球体,另外4个栽培种(阿尔格夫、耶罗林、萨莫和西伯利亚)为长椭球体。脊宽为1.20~2.78 μm,多由盘珠状颗粒或瘤状颗粒组成;网眼大小2.11~7.66 μm,多为不规则多边形至近圆形,大小不一,部分有刺状或粒状突起,少数无突起。大花卷丹和红骑士花粉的表面纹饰为单、双排基柱并存网纹,其他10个品种均为单基柱网纹。花粉粒均以单粒形式存在,极面观为椭球体,赤道面观为舟形,具单沟萌发孔,沟长达两端。通过对12个百合品种花粉形态特征比较及聚类分析表明,细叶百合与兰州百合、卷丹与大花卷丹、阿尔格夫与萨莫、普瑞头与多安娜亲缘关系较近,12个种大致可以划分为3大类群。     

贵州野豌豆属植物的核型研究

对贵州窄叶野豌豆，广布野豌豆，光叶紫花苕和救荒野豌豆４种野豌豆及其种下不同类元的核型进行了研究，结果表明，广布野豌豆和光叶紫药苕的染色体数目为２ｎ＝１４，属于较为原始的类群，窄叶野豌豆和救荒野豌豆的染色体数目２ｎ＝１２，属于较进化的类群，窄叶野豌豆和救野荒豌豆下类元的核型研究表明，种下类元间的核型差异明显，并对野豌豆属核型的趋势作进行了探讨。     

卫星搭载不同紫花苜蓿品种花粉形态的扫描电镜观察

应用扫描电镜对卫星搭载的2个紫花苜蓿(Medicago sativa L.)品种的花粉显微结构进行了观察研究.结果表明:花粉为长球形和近球形2种,赤道面观为椭圆形,极面观为三裂圆形,具3(拟)孔沟,沟为条形,狭缝状,沟长至两极,孔处有外突或无;花粉外壁纹饰为穴状、粗糙状、网状3种;花粉的外壁纹饰不同品种间以及同一品种的不同处理间均有差异.这2个紫花苜蓿品种的花粉形状、大小和外壁纹饰与地面对照对应品种的花粉存在显著差异(P＜0.05),表明空间飞行因子可导致花粉发育异常及可遗传突变等诱变效应.卫星搭载的2个品种存在花粉败育,不同品种间败育花粉数量存在差异.败育花粉粒形状干瘪,外形异常.     

贵州几种野豌豆属植物的核型研究

对贵州广布野豌豆、小巢菜、四籽野豌豆、黑荚野豌豆四种牧草的核型进行的研究结果表明，广布野豌豆、小巢菜、四籽野豌豆的染色体数目为2n=12，属于较为进化的类群，而黑荚野豌豆的染色体数目为2n=14，为较原始的类群。     

野豌豆属14个种牧草幼苗形态多样性与分类鉴定方法的研究

以包括14个种的37份野豌豆属材料为研究对象,并根据幼苗形态对其进行分类鉴定.研究结果表明,14个野豌豆种间表现出丰富的变异,最大变异系数为67.00％,遗传多样性信息指数最大,达到1.94.幼苗各性状间存在广泛而复杂的相关关系,依据性状间的关系,可以快速了解植物各性状的情况.聚类分析结果表明37份材料分为两大类,第一...     

柠檬花粉形态的初步观察

利用扫描电子显微镜观察10份柠檬种质的花粉形态,500倍观察花粉粒群体,3000倍观察赤道面和极面,10000倍观察外壁纹饰。结果表明：10份柠檬种质的花粉类型均属于单粒花粉,外观形态为长球形、近球形和扁球形三类,大小等级为小的花粉,萌发孔沟4～5条,沟长均直达两极,沟沿极轴方向等距环状分布,外壁纹饰均属于网状雕纹。10份柠檬种质两两之间在花粉极轴长、赤道轴长、萌发沟数量及外壁纹饰上,均存在一个或者一个以上的极显著差异或显著差异,因此,可作为不同柠檬种质之间鉴定的依据。     

野豌豆属种子形态多样性与种子分类鉴定方法的研究

本研究以48份野豌豆属的14个种为研究对象,以17个种子表型性状来揭示野豌豆属表型性状的遗传多样性,并对其进行分类鉴定.结果表明:种子表型性状种间变异较大,数量性状中百粒重变异系数最大,为81.92％,种形指数的Shannon多样性信息指数最大,为1.94;质量性状中种脐颜色的变异系数最大,为75.12％,其Shann...     

Morphometric analysis of the corneal endothelium of Yacare caiman (Caiman yacare) using scanning electron microscopy

The objective of this study was to examine the endothelial surface morphology and to perform morphometric analysis of the corneal endothelial cells of Yacare caiman (Caiman yacare) using scanning electron microscopy. Morphometric analysis with regard to polygonality, mean cell area, cell density and coefficient of variation of mean cell area was performed. Cell areas were measured using image analysis software. The normal corneal endothelium of Yacare caiman consisted of polygonal cells of uniform size and shape with interdigitations of the cell borders. Microvilli appeared as protrusions on the cellular surface. The average cell area was 270 +/- 24 microm(2) and the endothelial cell density was 3704 +/- 324 cells/mm(2). The coefficient of variation of cell area was 0.22. This study demonstrates that the Yacare caiman corneal endothelium is similar to those described in other vertebrates.     

Investigation of morphological changes of HPS membrane caused by cecropin B through scanning electron microscopy and atomic force microscopy

BackgroundAntimicrobial peptides (AMPs) have been identified as promising compounds for consideration as novel antimicrobial agents.ObjectivesThis study analyzed the efficacy of cecropin B against Haemophilus parasuis isolates through scanning electron microscopy (SEM) and atomic force microscopy (AFM) experiments.ResultsCecropin B exhibited broad inhibition activity against 15 standard Haemophilus parasuis (HPS) strains and 5 of the clinical isolates had minimum inhibition concentrations (MICs) ranging from 2 to 16 μg/mL. Microelectrophoresis and hexadecane adsorption assays indicated that the more hydrophobic and the higher the isoelectric point (IEP) of the strain, the more sensitive it was to cecropin B. Through SEM, multiple blisters of various shapes and dents on the cell surface were observed. Protrusions and leakage were detected by AFM.ConclusionsBased on the results, cecropin B could inhibit HPS via a pore-forming mechanism by interacting with the cytoplasmic membrane of bacteria. Moreover, as cecropin B concentration increased, the bacteria membrane was more seriously damaged. Thus, cecropin B could be developed as an effective anti-HPS agent for use in clinical applications.     

野豌豆属43份牧草种质的染色体形态观察与分析

野豌豆属(Vicia)牧草为自花授粉二倍体植物,具有很好的防风固沙及保水作用,适宜在高寒和高海拔地区种植,是我国高原牧区重要的蛋白饲料来源。本研究从中国、美国、德国、埃塞俄比亚等22个国家,收集了43份野豌豆属牧草种质,对其根尖细胞的有丝分裂中期染色体进行核型分析。结果表明,染色体数目有5种:10、12、14、16、24。核型分类有6种:2A、1B、2B、3B、2C、3C。本研究统计了野豌豆属43份种质的核型数据,为揭示野豌豆属细胞学特性和演化趋势奠定了基础。     

Corrosion casting of the cardiovascular structure in adult zebrafish for analysis by scanning electron microscopy and X-ray microtomography

Zebrafish have come to the forefront as a flexible, relevant animal model to study human disease, including cardiovascular disorders. Zebrafish are optically transparent during early developmental stages, enabling unparalleled imaging modalities to examine cardiovascular structure and function in vivo and ex vivo. At later stages, however, the options for systematic cardiovascular phenotyping are more limited. To visualise the complete vascular tree of adult zebrafish, we have optimised a vascular corrosion casting method. We present several improvements to the technique leading to increased reproducibility and accuracy. We designed a customised support system and used a combination of the commercially available Mercox II methyl methacrylate with the Batson's catalyst for optimal vascular corrosion casting of zebrafish. We also highlight different imaging approaches, with a focus on scanning electron microscopy (SEM) and X-ray microtomography (micro-CT) to obtain highly detailed, faithful three-dimensional reconstructed images of the zebrafish cardiovascular structure. This procedure can be of great value to a wide range of research lines related to cardiovascular biology in small specimens.     

Musculoskeletal responses of 2-year-old Thoroughbred horses to early training. 8. Quantitative back-scattered electron scanning electron microscopy and confocal fluorescence microscopy of the epiphysis of the third metacarpal bone

AIM: To characterise and explain the increase in density evident by computerised tomography (CT) and radiography in companion studies as a response to training, in bone in the palmar and dorsal regions of the condyles of the third metacarpal bone (Mc3) of 2-year-old Thoroughbred horses.

METHODS: Compositional back-scattered electron (BSE) imaging in scanning electron microscopy (SEM) and confocal scanning laser microscopy (CSLM) were conducted on polymethyl methacrylate (PMMA)-embedded mediolateral slices of the right distal Mc3 from seven 2-year-old Thoroughbred horses trained on a racetrack and seven untrained horses kept at pasture. One left Mc3 from each group was studied in transverse section planes. This study focussed on regions of Mc3 found to differ in density between the trained and untrained horses in companion studies using CT and radiography.

RESULTS: The increase of bone density in the condyles of Mc3 in trained horses compared with untrained horses occurred, without prior osteoclastic resorption, via the deposition of new bone on pre-existing internal surfaces. Within prior marrow spaces of cancellous bone, there was also rapid formation of immature strands and fronds of bone which were more cellular and mineralised, and more lamellar bone tissue was deposited on these new scaffolding elements in the trained horses. Both resulted in increased bone volume fraction (BVF). The microscopic mineralisation density of the bulk of the new tissue was lower than in pre-existing bone, and CT and radiography underestimated the increase in BVF. The new tissue was thus probably less stiff at the microscopic scale than pre-existing bone, though its addition would stiffen the global structure.

CONCLUSIONS: In Mc3 of all the trained horses, there were obvious differences in microscopic structure compared with those from the untrained horses. Moderate, industry-standard levels of exercise used to prepare young horses for racing induced the formation of new bone in non-bone spaces in bone tissue, such that the bone organ should better withstand later increased levels of exercise.     

Virus enteritis of mink. A scanning electron microscopic investigation

Advanced lesions in the jejunal mucosa in virus enteritis of mink were studied by scanning electron microscopy. The changes were found to be in good accordance with those observed in the light microscope, and included ballooned degeneration of entero-cytes, epithelial desquamation, the occurrence of fibrinous pseudo-membranes, atrophy or total loss of villi; partially atrophied villi were frequently fused. In some areas there were incipient regenerative processes, including proliferation of ballooned cells which covered the luminal surface of the damaged jejunal wall.     

鹅生长发育过程中小肠绒毛形态发育的扫描电镜观察

为探究鹅个体发育过程中小肠绒毛形态发育情况,通过扫描电子显微镜对鹅胚胎发育过程中和成体的小肠绒毛进行形态学观察。结果表明:鹅胚胎时期,小肠绒毛经历了由山脊状黏膜褶发育为“W”形板状黏膜嵴最后变为指状绒毛的过程;出雏后,鹅小肠绒毛形态由指状变回板状。其中,鹅胚胎发育18 d后(胚胎发育的60%阶段后),小肠表面黏膜由山脊状黏膜褶变为规则的“W”形板状黏膜嵴。发育25 d后(胚胎发育的83.3%阶段后),板状黏膜嵴均变为指状绒毛。鹅胚孵出8 d后小肠指状绒毛开始变扁,17 d龄鹅的小肠指状绒毛变成板状绒毛,成体鹅一直保持板状绒毛形态。     

Site adaptations of Acanthogyrus (Acanthosentis) tilapiae: Observations through light and scanning electron microscopy

Acanthogyrus (Acanthosentis) tilapiae parasites were collected from the intestines of 300 fish belonging to three tilapia species sourced at the River Nile, Giza, Egypt. The proboscis of the parasite was characterized by three rows of hooks that curved towards the posterior of the body. The first row is supported by unmodified hooks. The parasite tegument has a series of alternative folds and a large number of pores. Sensory ganglia are located on the surface of the proboscis and body. Acanthogyrus (Acanthosentis) tilapiae provokes an aggressive host response indicated by hyperplasia of the intestinal goblet cells and focal eosinophil infiltrations. This acanthocephalan parasite shows a highly modified adaptation to its site of host infection.