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Although the use of hypochlorite to disinfect seeds is widespread, the effects on tissues isolated from them have been largely ignored. Disinfection of barley ( Hordeum vulgare L. cv. Himalaya) half-seeds with hypochlorite solutions of ≥1.0% (w/v) available chlorine caused the pericarp to separate from the underlying tissues. Aleurone layers isolated from these grains had lower rates of oxygen consumption and released significantly less protein, PO4 3− Mg2+ , K+ and amylase (EC 3.2.1.1) into the medium in response to gibberellic acid (GA3 ) than layers isolated from grains disinfected with a 0.1% hypochlorite solution. Disinfection with 1.0% hypochlorite also quantitatively altered the spectrum of proteins released into the incubation medium by the layers in response to GA3 . 相似文献
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Relation of precipitation and temperature with yield of herbaceous plants in eastern Oregon 总被引:2,自引:0,他引:2
Forrest A. Sneva 《International journal of biometeorology》1982,26(4):263-276
Eighteen years of herbage yields of range grasses and concomitant precipitation and temperature fluctuations were examined with correlation and regression techniques. Antecedent precipitation was the dominant factor influencing yield of perennial herbaceous species, while both temperature and precipitation were important for prediction of yield of downy bromegrass, a winter annual. Total yield of the herbaceous community was closely correlated with precipitation received during the September to June period (r = 0.92); however, September to March precipitation was also highly correlated (r = 0.89). These correlations provide timely and useful estimates of native range production on eastern Oregon ranges. Sixty to 92% of yield variation was accounted for by the regression models for 9 of the 12 species or species groups examined. 相似文献
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Synthetic methoxatin or its reduced derivative, is fully active in the reconstitution of glucose dehydrogenase from Acinetobacter calcoaceticus var. anitratus from apoenzyme, and is also active in a similar reconstitution of enzyme from A. calcoaceticus ATCC 9956. However, we have still not been able to reconstitute holoenzyme of methanol dehydrogenase from Pseudomonas TPI. 相似文献
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Christopher B Forrest 《BMJ (Clinical research ed.)》2003,326(7391):692-695
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