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201.
Culture conditions which lead to the intracellular accumulation of arabitol and mannitol in Geotrichum candidum were investigated. The accumulation of arabitol was dependent on the concentrations of metabolizable hexoses, the non-metabolizable disaccharide sucrose, NaCl and KCl in the growth medium. In media containing 2% (w/v) glucose, fructose or l-sorbose cultures contained only mannitol after 48 h or 72 h growth. In media containing 10% (w/v) to 30% (w/v) glucose, or 25% (w/v) fructose or l-sorbose there was an increase in the total concentration of intracellular polyol due to the accumulation of arabitol. This pentitol was also found to accumulate intracellularly when the organism was grown in medium containing 34% (w/v) sucrose, 0.7 M NaCl or 0.7 M KCl in addition to 2% (w/v) glucose. Under the conditions tested no change in the accumulation of mannitol or ethanol-soluble carbohydrate, believed to be primarily composed of trehalose, was evident.Intracellular polyol was released during incubation of arthrospores obtained from media containing 25% or 10% glucose, in distilled water at 25° C, but no polyol was released under these conditions from arthrospores obtained from growth in 2% glucose medium. 相似文献
202.
Summary Four siblings with the autosomal recessive Roberts syndrome are reported, and we discuss the phenotypic overlap of this syndrome with other similar radial, aplasia syndromes. 相似文献
203.
204.
Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448
205.
206.
Lysine-ketoglutarate reductase activity was detected and characterized in the developing endosperm of maize (Zea mays L.). The enzyme showed specificity for its substrates: lysine, α-ketoglutarate, and NADPH. Formation of the reaction product saccharopine was demonstrated. The pH optimum of the enzyme was close to 7, and the Km for lysine and α-ketoglutarate were 5.2 and 1.8 millimolar, respectively. 相似文献
207.
208.
Summary The frequency of sister chromatid exchanges (SCE) and chromosome aberrations and the dynamics of cell division in peripheral blood lymphocytes of four patients with Fanconi's anemia were studied after in vitro exposure to alkylating agents TEPA and mitomycin.SCE frequency was significantly increased even after very low doses of mutagens, while chromosome aberrations were significantly increased only after high doses (0.160 g/ml mitomycin and 10-5
M TEPA). The responses of Fanconi's anemia cells and control cells did not differ significantly. The increased frequency of both SCE and chromosome aberrations was accompanied by gradual delay of cell division, which was most conspicuous in cells from patients with Fanconi's anemia. 相似文献
209.
Transport of thiomethyl-β-D-galactoside (TMG) via the melibiose permease system (TMG permease II) in is known to be a sodium-dependent co-transport system. We have shown that this co-transport of sodium and TMG is associated with extrusion of protons from the cells. The rate and extent of proton extrusion during TMG uptake were measured in wild-type cells and mutants containing internal and extended deletions in the locus. No differences between these various strains were noted. 相似文献
210.
S O Andrade H O da Silva Lopes M de Almeida Barros G G Leite S M Dias M Saueressig D Nobre J A Temperini 《Arquivos do Instituto Biológico》1978,45(2):117-136
Aspects of photosensitization in bovines grazing on pastures of Brachiaria decumbens Stapf infested with Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures 45(2):117-136, 1978. This paper reports experimental studies on photosensitization in bovines grazing on different pastures of Brachiaria decumbens Stapf in the "Cerrados" region (Planaltina, DF). Climatic conditions, zinc content and occurence of fungi on pastures were investigated. Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures examined. Photosensitization was observed in one animal maintained on a pasture of B. decumbens formed with seeds from Australia. Clinical and necropsy data were similar to those related in literature for sporidesmin-intoxicated animals. An isolate of P. chartarum and samples of bovine bile were assayed for sporidesmin presence. 相似文献