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991.
Escherichia coli and Bacillus megaterium rendered permeable to ribonucleoside triphosphates by toluene treatment retain the capacity to synthesize discrete ribonucleic acid species. 相似文献
992.
Complementary Functioning of Nitrogenase Components from a Blue-Green Alga and a Photosynthetic Bacterium 总被引:4,自引:1,他引:3
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Nitrogenases from Anabaena cylindrica and Chloropseudomonas ethylicum were partially purified into two components. A. cylindrica fraction I protein complemented fraction II protein from C. ethylicum. However, the reciprocal cross between C. ethylicum fraction I and A. cylindrica fraction II was negative. 相似文献
993.
Changes in Hepatic Glycogen, Protein, and Ribonucleic Acid Synthesis, and Some Effects of Cortisol, During Q Fever 总被引:6,自引:0,他引:6
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Liver glycogen is depleted in guinea pigs infected with Coxiella burneti. Syntheses of the glycogen precursors uridine triphosphate and uridine diphosphate glucose are unaffected during Q fever, but glycogen synthetase activity is inhibited. Exogenous cortisol relieves this inhibition in infected animals. Orotate and amino acids are more rapidly incorporated into ribonucleic acid and protein during infection. It is proposed that the biochemical defect in the synthesis of glycogen lies in the inactivation of glycogen synthetase. 相似文献
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The transport of abscisic acid in cotyledonary petiole sectionsof cotton seedlings was investigated using (2-14C)-ABA in adonor-receiver system. Using the intercept technique, a transportvelocity of 22.4 mm/hr was determined. This velocity was foundto be independent of the length of the petiole or of the concentrationof ABA applied. In a 24-hr period 70% of the applied ABA movedthrough the tissue sections. No polarity was found in any ofthe studies. The capacity of the transport system decreased with increasingage of the tissue and with increasing time of pre-exposure toABA. When metabolism of the tissue was restricted by cold temperature,low-O2 tension or DNP treatment, transport was inhibited 80to 98%.The distribution of ABA in the petiole during transportwas also investigated. The results are discussed in relationto the well-studied transport of IAA and in relation to thephysiologicalrole of ABA.
1 Present address: Stanford Research Institute-Irvine, 19722Jamboree Blvd., Irvine, Calif. 92664, U.S.A. (Received November 30, 1970; ) 相似文献
1000.
Summary Twelve different chemical extraction procedures for extracting soil manganese were used. Soil test values determined for fourteen
representative soil samples of Rajasthan State with manganese uptake by six crop species have shown that of the extractants
used, 3N ammonium dihydrogen orthophosphate can be best used for estimating plant available soil manganese. 相似文献