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92.
A higher‐level classification of the Pannonian and western Pontic steppe grasslands (Central and Eastern Europe) 下载免费PDF全文
Wolfgang Willner Anna Kuzemko Jürgen Dengler Milan Chytrý Norbert Bauer Thomas Becker Claudia Biţă‐Nicolae Zoltán Botta‐Dukát Andraž Čarni János Csiky Ruzica Igić Zygmunt Kącki Iryna Korotchenko Matthias Kropf Mirjana Krstivojević‐Ćuk Daniel Krstonošić Tamás Rédei Eszter Ruprecht Luise Schratt‐Ehrendorfer Yuri Semenishchenkov Zvjezdana Stančić Yulia Vashenyak Denys Vynokurov Monika Janišová 《应用植被学》2017,20(1):143-158
93.
S. Mormeneo Hortensia Rico María Iranzo Carmen Aguado Rafael Sentandreu 《Archives of microbiology》1996,166(5):327-335
Candida albicans cell wall components were analyzed by ethylenediamine (EDA) treatment. Based on their different solubility properties, the
cell wall components produced three fractions (A, B, and C). Fractions B (EDA-soluble, water-insoluble) and C (EDA-insoluble)
contained glucan, chitin, and protein in different proportions. After zymolyase (mainly a β-glucanase complex) or chitinase
treatment of fractions B and C, more polysaccharides and proteins were solubilized by a second EDA treatment, suggesting that
the solubility of the polymers in EDA depends on the degree of polymer interactions. Western blot analysis using two monoclonal
antibodies (1B12 and 4C12) revealed electrophoretic patterns that were similar in mycelial and yeast morphologies, except
that in material obtained from mycelial walls, an additional band was detected with MAb 1B12. Fluorescence microscopy of cell
wall fractions treated with FITC-labeled Con-A, Calcofluor white, and FITC-labeled agglutinin showed that glucan and mannoproteins
are uniformly distributed in fractions B and C, while chitin is restricted to distinct patches. Transmission electron microscopy
demonstrated that fraction C maintained the original shape of the cells, with an irregular thickness generally wider than
the walls. When fraction C was treated with chitinase, the morphology was still present and was maintained by an external
glucan layer, with an internal expanded fibrillar material covering the entire cellular lumen. Degradation of the glucan skeleton
of fraction C with zymolyase resulted in the loss of the morphology.
Received: 1 April 1996 / Accepted: 2 September 1996 相似文献
94.
Escherichia coli was grown at 37°C with increasing cholesterol concentrations in the growth medium. Under these conditions, it was shown that neither the phospholipid species nor the fatty acid composition were affected by the incorporation of cholesterol. On the other hand, the doubling time (td) was increased; two membrane-bound enzymes, (Ca++)-ATPase and D-lactate-dehydrogenase, were modified in the temperature-dependence activities, and the (Ca±±)-ATPase changed its Hill coefficient for the inhibition by Na+. This last parameter was the most sensitive in detecting very low cholesterol incorporations to the cytoplasmic membranes. 相似文献
95.
Maria S. Budeguer de Atenor Hortensia Salomn de Legname Arnaldo H. Legname 《Molecular reproduction and development》1989,23(3):349-356
In the fully grown Bufo arenarum oocyte, carbohydrate breakdown during the autumn-winter season is accomplished mainly through the glycolytic pathway followed by the krebs cycle. During the breeding season (spring-summer), carbohydrates are used mainly through the pentose phosphate cycle and through the variant of the Krebs cycle known as the glutamic aspartic cycle. The metabolism operating in the oocytes was determined using the following paramenters: 1) the capacity of isolated mitochondria to oxidize citrate and fumarate; 2) the enzymatic activities of phosphofructokinase (PEK) and glucose-6-phosphate dehydrogenase (G-6-PDH); and 3) cirate and ATP compartmentalization. The present paper shows that follicle-stimulating hormone (FSH) would be one of the factors responsible for summer metabolism, since ovary fractios obtained from winter specimens treated with the hormone acquired the metabolic characteristics corresponding to oocytes obtained from breeding-season animals from dose-response, and response in the function of time curves, it could be assumed that the optimum doses and times were 0.1 μg FSH/ml of incubation medium and 30 min treatment, respecitively. The metabolic effect of FSH upon oocytes could be mediaated by the adenylate cyclase cAMP system, since treatment of ovric fractions with cAMP 10-3 M reproduced the effects obtained with the hormone. In addition, 0.02 mg/ml tetracyline proved to block the effect of FSH. A direct metabolic action of FSH on body cavity oocytes (without follicle cells) was observed when submitting these oocytes to the same hormonal treatment. 相似文献