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Ganglioside Composition in Human Meningiomas   总被引:4,自引:3,他引:1  
The ganglioside composition in meningioma specimens from 20 patients was analyzed to find potential meningioma-associated structures. The characterization was performed by immunological staining with specific monoclonal antibodies to ganglioside antigens and fast atom bombardment-mass spectrometry. The major gangliosides were GM3 and GD3, and most of the meningioma specimens could be divided into a "GM3-rich" or a "GD3-rich" group. Gangliosides of the gangliotetraose series were represented by GM1, GD1a, GD1b, and GT1b, which were found in minor amounts in all the specimens. The ratios of GM1/GD1a and GD1a/GD1b differed from that in normal brain, and therefore existence of this series could not be explained by contamination with brain material. Ganglioside 3'-isoLM1, found in human malignant glioma, could not be detected in any meningioma specimen.  相似文献   

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Data on the lipid composition and carbohydrate composition of Aspergillus niger conidia make it possible to characterize the individual germination stages and differentiate between the conidia capable of germination and those that lost the germination capacity. The following criteria are proposed: the ratio of phosphatidylcholine and phosphatidylethanolamine, the ratio of mannitol and arabitol, and the levels of sterols and free fatty acids. The role of these compounds in the biochemical background of cell transition from dormancy to active metabolism and their use as indices of the quality of inocula in biotechnological processes are discussed.  相似文献   

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Abstract: The aim of the present study is to ascertain lipid composition in the ganglia of Mollusca. Nervous ganglia in the periesophageal ring dissected from Helix pomatia, Lymnaea stagnalis, Murex trunculus and Murex brandaris were studied by biochemical and histochemical procedures. Glycosphyngolipids are present mainly as sulpholipid; sialic acid and gangliosides are not present as revealed by Svennerholm's reaction and TLC separation. The phospholipidcholesterol ratios are: 0.47 ( Helix ), 0.42 ( Lyrnnaea ), 0.86 ( Murex brandaris ) and 1.01 ( Murex trunculus ).  相似文献   

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To establish a standard for genotype/phenotype studies on the myelin of zebrafish (Danio rerio), an organism increasingly popular as a model system for vertebrates, we have initiated a detailed characterization of the structure and biochemical composition of its myelinated central and peripheral nervous system (CNS; PNS) tissues. Myelin periods, determined by X-ray diffraction from whole, unfixed optic and lateral line nerves, were approximately 153 and approximately 162 Angstrom, respectively. In contrast with the lability of PNS myelin in higher vertebrates, zebrafish lateral line nerve myelin exhibited structural stability when exposed to substantial changes in pH and ionic strength. Neither optic nor lateral line nerves showed swelling at the cytoplasmic apposition in CaCl(2)-containing Ringer's solution, in contrast with nerves from other teleost and elasmobranch fishes. Zebrafish optic nerve showed greater stability against changes in NaCl and CaCl(2) than lateral line nerve. The nerves from zebrafish having mutations in the gene for myelin basic protein (mbpAla2Thr and mbpAsp25Val) showed similar myelin periods as the wildtype (WT), but gave approximately 20% less compact myelin. Analysis of proteins by SDS-PAGE and Western blotting identified in both CNS and PNS of WT zebrafish two orthologues of myelin P0 glycoprotein that have been characterized extensively in trout--intermediate protein 1 (24 kDa) and intermediate protein 2 (28 kDa). Treatment with endoglycosidase-F demonstrated a carbohydrate moiety of approximately 7 kDa, which is nearly threefold larger than for higher vertebrates. Thin-layer chromatography for lipids revealed a similar composition as for other teleosts. Taken together, these data will serve as a baseline for detecting changes in the structure and/or amount of myelin resulting from mutations in myelin-related genes or from exogenous, potentially cytotoxic compounds that could affect myelin formation or stability.  相似文献   

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The study investigates how the human body composition (BC) changes as a function of the day-night cycle. The BC was investigated using bioelec-trical impedance analysis (BIA) of 10 clinically healthy subjects (CHS), mon-itored in supine position (readings at 2-h intervals), avoiding mealtimes, di-etary abuses, and bladder and intestinal retention. Time series data were analyzed for their temporal characteristics and circadian rhythm (CR). Ail the variables of BC (lean body mass, fat body mass, body cell mass, total body water, intracellular and extracellular body water, sodium and potassium exchangeable pool) showed a within-day variability with nighttime crests. Such an oscillatory synchronism corroborates the hypothesis that the rest time plays a fundamental role, via its anabolic effects, in conferring the noc-turnal phase to the CR of the human BC.  相似文献   

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Cytoskeleton Structure and Composition in Choanoflagellates   总被引:4,自引:0,他引:4  
The structure and composition of the cytoskeleton has been studied in Monosiga ovata (Protozoa: Order Choanofiagellida Kent 1880) using a combination of methods in association with light and electron microscopy. Supplementary observations are included for Desmarella moniliformis. The basal body of the single anterior flagellum is subtended proximally and at right angles by a second, non-flagellar basal body. The edges of the two basal bodies are connected by a fibrillar bridge. A long, narrow, striated, fibrillar rootlet extends posteriorly from the lower edge of the non-flagellar basal body towards the Golgi apparatus. It is associated throughout most of its length with the surface of a flattened sac. Rootlet microtubules pass radially from a ring of electron dense material which encircles the distal end of the flagellar basal body. These microtubules extend outwards for about one-third of the length of the cell. Within each collar tentacle is a longitudinal bundle of microfilaments composed of actin as illustrated by rhodamine-phalloidin staining for fluorescence microscopy. The base of each microfilament bundle is associated with one or more rootlet microtubules by fine fibrillar bridges. The attachment between microtubules and tentacle microfilaments is further demonstrated by their coordinated displacement when the cytoskeleton becomes dislodged. The role of the cytoskeleton in maintaining the position of the collar tentacles during interphase and cell division is discussed.  相似文献   

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Deoxyribonucleic Acid Base Composition in Yeasts   总被引:6,自引:3,他引:3       下载免费PDF全文
The deoxyribonucleic acid base composition of 15 species of yeasts was determined to obtain further clues to or supporting evidence for their taxonomic position. Species examined belonged to the genera Saccharomyces, Debaryomyces, Lodderomyces, Metschnikowia, and Candida. The range of moles per cent guanine plus cytosine (GC content) for all yeasts examined extended from 34.9 to 48.3%. The sporogenous species and the asporogenous yeasts spanned the range with 36.6 to 48.3% GC and 34.9 to 48% GC, respectively. Three Saccharomyces species (S. rosei and related species) exhibited significantly higher GC contents than S. cerevisiae, whereas the fermentative species D. globosus revealed a%GC more aligned to the S. rosei group than to the nonfermentative D. hansenii. Similar GC contents were demonstrated by L. elongasporus and its proposed imperfect form C. parapsilosis. The range of GC contents of various strains of three Metschnikowia species studied was 6.1%, with the type strain of M. pulcherrima having the highest GC content (48.3%) of all of the yeasts examined.  相似文献   

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利用超高效液相色谱质谱联用(I-Class UPLC/Xevo TQ MS)技术, 对50个品种荷花干燥花粉中的类黄酮代谢产物进行了分离及结构鉴定。结果表明, 在荷花(Nelumbo nucifera)花粉中检测到了13种黄酮醇和2种黄酮, 这15种类黄酮化合物均为首次从荷花花粉中检出, 其中槲皮素3-O-葡萄糖醛酸苷(quercetin 3-O-glucuronide)、槲皮素3-O-新橙皮糖苷(quercetin 3-O-rhamnopyranosyl-(1→2)-glucopyranoside)以及槲皮素3-O-阿拉伯糖-(1→2)-半乳糖苷(quercetin 3-O-arabinopy- ranosyl-(1→2)- galactopyranoside)含量较高, 且在所有品种中均有检出。不同品种花粉中检测到的类黄酮总含量(TF)差异较大, 绯云千叶类黄酮总含量最高, 为281.08 mg∙100 g-1; 仙女散花最低, 仅为82.64 mg∙100 g-1。通过聚类分析, 将50个品种聚为4组, B组类黄酮化合物种类最多, 而且该组总类黄酮含量最高, 其中绯云千叶、伯里小姐和蜀红莲的干燥花粉中总类黄酮含量均超过200 mg∙100 g-1, 可推荐为采集荷花花粉用的优良品种。  相似文献   

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Variation in Composition of Yeast Phosphohexosans   总被引:3,自引:1,他引:2       下载免费PDF全文
Omitting of KH(2)PO(4) from culture media leads to the production of altered phosphohexosans or neutral extracellular mannans by yeasts that otherwise elaborate phosphogalactans and phosphomannans.  相似文献   

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Composition of lipids in stallion semen   总被引:1,自引:0,他引:1  
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Algivorous ciliates represent an important link in freshwater food webs, as they transfer energy and biochemical matter from their algal prey to mesozooplankton predators. However, it is still unknown how dietary composition influences the biochemical composition of ciliates. We analyzed the sterol composition of the algivorous ciliates Balanion planctonicum and Urotricha farcta and compared it to the sterol composition of their diet—the cryptomonad Cryptomonas phaseolus. The sterol composition of the ciliates did not resemble that of their algal diet. Ergosterol [(22E)-ergosta-5,7,22-trien-3β-ol] was the sterol in highest concentration in C. phaseolus, whereas stigmasterol [(24S)-24-ethylcholesta-5,22E-dien-3β-ol] was dominant in both B. planctonicum and U. farcta. Moreover, the occasionally higher sterol concentrations in the ciliates than in their algal diet suggest sterol accumulation by the ciliates. We conclude that dietary sterol composition influences the composition of the two algivorous ciliates studied, but species-specific differences in metabolism probably determine the ultimate sterol composition of the ciliates.  相似文献   

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山西野生有毒植物组成   总被引:5,自引:1,他引:4  
有毒植物是能引起人类或其它生物中毒死亡或有机体长期或暂时性伤害的植物。但是,有毒植物也有积极有益的一面.在人类生活、生产中起着很大作用。本文中重点介绍了山西有毒植物的组成.计47科、105属、150种.其中草本植物126种,木本植物24种.并对有毒部位与毒性作了说明.最后对有毒植物应用前景作了简要分析。  相似文献   

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The municipal garbage disposal plant in Turku converts all household garbage into ash by burning it in specially constructed ovens. For several years, the workers there have been complaining of allergy and skin diseases. An investigation was started in January, 1977, to determine the frequencies of pathogenic and allergenic fungi in the air inside this plant. The survey is being made four times during 1977 (two of these have already been carried out), using both Petri dish method and Hirst-Burkard traps. The spore trap collections indicate that the seven sampling sites can be classified into three groups with regard to spore frequencies: (1) the dumping room and the room for crushing the wastes show extremely high frequencies (170 000-180 000 spores/m3), with Penicillium and Aspergillus as the main spore types. (2) In the furnace unit the frequencies are clearly higher than in normal indoor air (over 10 000 spores/m3). (3) In the washing, dressing and control rooms the frequencies are about the same as in the indoor air in general, or even lower. The Petri dish collections gave similar results; e.g. the concentrations of Penicillium and Aspergillus in the dumping room are 6000-fold when compared with the outdoor air. The wide variations in the spore contents are directly correlated with the kind of garbage under treatment. The outdoor air collected at a distance of c. 200m showed no conspicuous differences when compared with the air in Turku in general. These results indicate that it is absolutely necessary to use face masks—at least in the dumping room conditions.  相似文献   

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