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I P Grigor'ev A A Neokesari?ski? 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(9):288-289
The effects of different concentrations of L-ascorbic acid (Asc) on Na+-dependent binding of 3H-GABA and 3H-DL-glutamic acid to rat brain cortical synaptosomes were studied. Asc, at a concentration nearly equal to brain extracellular one (3 X 10(-4) M), had no effect on specific and nonspecific 5H-GABA binding. At higher concentrations (10(-3) M) Asc strongly inhibited, and at lower concentrations (10(-6) M) considerably stimulated 3H-GABA binding. At a concentration of 10(-5)-10(-3) M Asc tended to decrease 3H-DL-glutamic acid binding. 相似文献
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M. Filek J. Biesaga-Kościelniak I. Marcińska M. Cvikrová I. Macháčková J. Krekule 《Biologia Plantarum》2010,54(3):483-487
The contents of endogenous free and conjugated polyamines, putrescine (Put) and spermidine (Spd), were determined during 9
week of vernalization (at 5 °C) in winter wheat seedlings cultivated on Murashige and Skoog media without (MS0) and with 2
mg dm−3 zearalenone (MSZEN). At the 4th week of chilling treatment, which is sufficient to induce generative development in 30 % of plants, the marked increase in
free and conjugated forms of Put and free Spd were observed. The presence of ZEN in medium significantly accelerated the vernalization.
About 20 % of plants treated with ZEN flowered already after 2 weeks and 40 % after 3 weeks of chilling. Significantly higher
content of free Put was determined in roots grown on MSZEN compared with MS0 during the first 5 weeks of vernalization with
maximum at the 4th week. After germination, a marked decrease in free Spd content was observed both in plants grown on MS0 and MSZEN. Application
of ZEN significantly slowed down the Spd decline in leaves and roots during the first and second week of vernalization. The
content of Spd and its conjugates decreased in vernalized plants after 1 week of cultivation at 20 °C. 相似文献
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