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31.
团网菌属粘菌一新种   总被引:1,自引:0,他引:1  
王琦  李玉 《植物研究》1996,16(2):179-181
本文报告了团网菌属粘菌的一个新种--瘤丝团网菌(Arcyria gongyloida),其主要特征为孢丝有明显的球形膨大,同时伴有半环及网纹。附有扫描电子显微镜照片,模式标本保存于吉林农业大学真菌标本室。  相似文献   
32.
This study obtained information on the biogeographical distribution of lignicolous myxomycetes in temperate regions in Japan. It examined how climatic variables are related to patterns of occurrence in myxomycete communities. Sixty-four taxa were recorded on coniferous wood in 15 forest sites in summer. Common species that were abundant and widely distributed in Japan included Stemonitis axifera, Lycogala epidendrum, and Cribraria cancellata. In addition, Lindbladia cribrarioides was characteristic on dead Pinus densiflora wood in southwestern Japan. The species diversity index (H′) of the myxomycete communities was positively correlated with the annual mean temperature. The distribution of myxomycete communities was analyzed using nonmultidimensional scaling (NMDS). The ecological nature of the gradients expressed by the first two NMDS axes was that the first axis was found to correspond strongly to changes in the average minimum temperature and the latitude, and the second axis was related to a complex of factors, including altitude. The relative abundance of certain species in a myxomycete community on Japanese red pine changed in relation to the annual mean temperature, e.g., Lycogala epidendrum correlated negatively while Stemonitopsis hyperopta did so positively. We conclude that air temperatures can be used to predict the geographical distribution of lignicolous myxomycetes in this temperate region of Japan.  相似文献   
33.
This report describes conditions under which spores of the acellular slime mold Fuligo septica underwent a very rapid, synchronous and complete (100%) germination followed by morphogenesis of motile, flagellated swarm cells from the released protoplasts. This developmental sequence was initiated immediately upon wetting the spores with a surfactant and was completed within 40–50 min in the absence of any exogenous nutrient other than sodium phosphate buffer. Oxygen was required for germination. The rate and percentage of germination diminished with increasing spore concentration suggesting the existence of an autoinhibitor. The morphological sequence of events in the differentiation process was examined by scanning electron microscopy.  相似文献   
34.
Microplasmodia of Physarum polycephalum exhibit high UDPG: sterol glucosyltransferase activity. The enzyme was purified about 28-fold by acetone pr  相似文献   
35.
报道了一个黏菌新变种,小筛菌大孢变种Cribraria microcarpa var.megaspora nov.var.,获得于湿室培养的采自云南大围山国家级自然保护区的柳杉Cryptomeria fortunei树皮上,其特征是比原变种具有明显较大的孢子。这里描述和图示了这个新变种,模式标本保存于南京师范大学微生物菌种保藏中心。  相似文献   
36.
云南黏菌汇录   总被引:3,自引:0,他引:3  
云南是我国生物多样性高度丰富的地区之一,蕴藏着丰富的黏菌资源。根据作者的研究、复核和考证,作者汇录了目前已知的分属于6目10科33属的云南黏菌135种10变种,其中27种为云南省首次记录,团孢发网菌(Stemonitis uviferaT.Macbr.)为中国新记录种。  相似文献   
37.
王晓丽  李玉 《菌物学报》2008,27(2):177-182
以扁绒泡菌显型原质团为材料,进行细胞核的提纯、核骨架的制备及电镜观察。结果表明:用2mol/LNaCl+TritonX-100/NP40可得到具有复合纤维的核骨架,而用Lis+TritonX-100/NP40得到的核骨架具有核纤层,不使用RNase得到了具有网状的细胞核骨架,RNA在核骨架的结构形态中起重要作用。阐述了原质团中游离细胞核在细胞生物学研究中的意义。  相似文献   
38.
针箍菌的生活史   总被引:3,自引:2,他引:1  
史立平  李玉 《菌物学报》2004,23(3):381-387
利用基物和燕麦-琼脂技术研究了针箍菌的个体发育过程,在燕麦琼脂培养基上完成了从孢子到孢子的生活史。结果表明,生活史包括单核的黏变形体或游动胞、多核的营养体原质团以及孢子形成阶段。琼脂培养基获得的针箍菌孢子与野生型相似,并具有可育性。  相似文献   
39.
Two novel polypropionate lactone glycosides (1 and 2, i.e. lycogalinosides A and B) were isolated from the slime mold Lycogala epidendrum. Their structures, including the absolute configurations of the hydroxyl and methyls groups, were determined by means of extensive spectroscopic data such as mass, IR, UV, and 1D and 2D NMR spectra and chemical degradation followed by spectroscopic and chromatographic analysis. Compounds 1 and 2 are unique in structure containing a 2-deoxy-alpha-L-fucopyranosyl-(1-4)-6-deoxy-beta-D-gulopyranosyl unit and a beta-D-olivopyranosyl-(1-4)-beta-D-fucopyranosyl unit, respectively, and showed growth inhibitory activities against Gram-positive bacteria.  相似文献   
40.
Zusammenfassung Die Ultrastruktur der mitotischen Kerne in den Plasmodien von Physarum polycephalum wurde mit der Dünnschnitt- und der Gefrierätztechnik untersucht.Die Kernhülle bleibt während der Mitose bis in die Telophase erhalten, löst sich dann aber zuerst in der Polgegend und später in der Interzone auf. Bläschen, welche mit Ribosomen besetzt sind, lagern sich an die membranfreien Stellen an und bilden, zusammen mit Teilen der alten Kernhülle, die Hülle der Tochterkerne. Die Porenkomplexe bleiben während der Mitose erhalten.Der Spindelapparat ist in der Metaphase aufgebaut aus durchgehenden Mikrotubuli, welche die Pole verbinden, und aus Kinetochor-Mikrotubuli, welche Chromosomen und Pol verbinden. Die scheibenförmigen Kinetochore 1500–2500 Å im Durchmesser, sind mit einem oder zwei Mikrotubuli verbunden.In der Anaphase erfolgt eine deutliche Streckung des Spindelapparates und eine geringe Verkürzung des Abstandes zwischen Chromosomen und Pol. Da die durchgehenden Mikrotubuli in der Telophase in der Polgegend divergieren, sind sie kaum direkt (durch Stoßen) an der Verlängerung des Spindelapparates beteiligt. Invaginationen der Kernhülle stimmen mit der Hypothese überein, daß während der Anaphasentrennung der Chromosomen Kontraktionswellen auftreten.Filamente, 30–90 Å im Durchmesser, wurden im Spindelapparat beobachtet. Ihre Anordnung und die Ähnlichkeit mit den cytoplasmatischen Filamenten von Physarum lassen vermuten, daß es sich um kontraktile Elemente handelt.
The ultrastructure of mitotic nuclei in plasmodia of Physarum polycephalum
Summary The ultrastructure of mitotic nuclei of Physarum polycephalum was investigated by freeze-etching and sectioning techniques.The nuclear envelope remains intact until telophase, and then dissapears first in the polar regions and later in the interzone. Vesicles covered with ribosomes accumulate in the resulting membrane-free areas, and contribute, together with portions of the old nuclear envelope, to the building of the new nuclear envelope. The nuclear pore complexes remain intact during mitosis.The mitotic apparatus in metaphase contains continuous microtubules connecting the two poles, and kinetochore-microtubules connecting chromosomes and poles. The disc-shaped kinetochores, 1500 to 2500 Å in diameter, are in contact with one or two microtubules.In anaphase the mitotic apparatus elongates markedly and the distance between chromosomes and poles shortens slightly. Since the continuous microtubules diverge in the polar regions, they are probably not directly involved in the elongation of the mitotic apparatus. Invaginations of the nuclear envelope indicate that the anaphase separation of chromosomes is accompanied by waves of contractions.Filaments, 30 to 90 Å in diameter, were observed in the mitotic apparatus. Their arrangement and their similarity with cytoplasmic filaments suggest that they are contractile.
Die vorliegende Arbeit wurde der Eidgenössischen Technischen Hochschule in Zürich als Dissertation vorgelegt.  相似文献   
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