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61.
Jean- -François Laliberté Olivier Nicolas Serge Durand Rolf Morosoli 《Plant molecular biology》1992,18(3):447-451
The xylanase gene from Cryptococcus albidus contains seven introns. Genomic and cDNA clones under the control of the CaMV 35S promoter were transferred into tobacco plants using Agrobacterium-mediated cell transformation. The genes were transcribed and the mRNAs were amplified by the polymerase chain reaction using primers on each side of the intron region. About 90% of the amplification products from plants transformed with the genomic clone corresponded to the size of the pre-mRNA (1.2 kb) and 10% represented the spliced product (0.85 kb). The 0.85 kb fragment was cloned and sequenced and the result indicated that the introns from the xylanase gene were accurately spliced by the plant cells. 相似文献
62.
63.
Up regulation of corticotrophin receptors by ACTH1-24 in normal and hypophysectomized rabbits 总被引:2,自引:0,他引:2
The number of ACTH binding sites, in adrenal membranes from adult female rabbits, has been measured at different times after hypophysectomy and after ACTH1–24 treatment. The receptor number was significantly reduced 192 h after removal of the pituitary gland as compared to intact controls. Conversely, ACTH treatment of intact rabbits enhanced the number of ACTH binding sites, or restored these levels to presurgical values in hypophysectomized animals. These results suggest that ACTH, like other hormones, is able to induce an increase in the number of its own receptors; the physiological significance of such variations remains however to be elucidated. 相似文献
64.
Britt-Marie Sjöberg Astrid Gräslund Joann Sanders Loehr Thomas M. Loehr 《Biochemical and biophysical research communications》1980,94(3):793-799
The iron-containing B2 subunit of ribonucleotide reductase from Escherichia coli has been investigated by Raman spectroscopy. Both the tyrosyl radical-containing native protein and the radical-free protein exhibit a resonance-enhanced Raman band at 500 cm?1. This band is assigned to an Fe-O vibrational mode arising from an oxygen-containing ligand. The failure to observe any tyrosinate ring modes makes it unlikely that ribonucleotide reductase is an iron-tyrosinate protein and rules out tyrosinate oxygen as a ligand. It is proposed that the 500 cm?1 band in ribonucleotide reductase is analogous to the 510 cm?1 Fe-O vibrational mode of methemerythrin and arises from an oxo- or carboxylate-bridge between the antiferromagnetically-coupled Fe(III) ions. 相似文献
65.
66.
Radioimmunoassays of platelet prostaglandins E1 and F1 alpha in platelet rich plasma or platelet suspension, demonstrate that both PGE1 and PGF1 alpha are present at higher concentrations than prostaglandins E2 and F2 alpha. Gas chromatography--mass spectrometry determinations of prostaglandins E1 and E2 in resting washed platelets confirm this difference. Lastly, there is a greater incorporation of [1--14C] acetate into prostaglandins E1 and F1 alpha compared to that into prostaglandins E2 and F2 alpha. 相似文献
67.
Michel Lagarde Marc Dechavanne Michel Rigaud Jacqueline Durand 《Prostaglandins & other lipid mediators》1979,17(5):685-705
Radioimmunoassays of platelet prostaglandins E1 and F1α in platelet rich plasma or platelet suspension, demonstrate that both PGE1 and PGF1α are present at higher concentrations than prostaglandins E2 and F2α. Gas chromatography — mass spectrometry determinations of prostaglandins E1 and E2 in resting washed platelets confirm this difference. Lastly, there is a greater incorporation of [1-14C] acetate into prostaglandins E1 and F1α compared to that into prostaglandins E2 and F2α. 相似文献
68.
Kinetic study of possible intermediates in the biosynthesis of chlorogenic acid in Cestrum poeppigii
p-Coumaric and 3-O-p-coumarylquinic acid seem to be important precursors of chlorogenic acid in the leaves of Cestrum poeppigii. 3-O-Cinnamylquinic acid, which has a very small metabolic activity, is of little importance in this respect. The kinetics of incorporation of radioactivity from t-cinnamic acid-3-[14C] into p-coumaric, 3-O-p-coumarylquinic, chlorogenic and 3-O-cinnamylquinic acid showed that the biosynthetic rates for these products decrease in the order shown. For p-coumaric acid, which has a markedly high metabolic activity, a turnover rate of 28 μg/hr and per gram fresh plant leaf, was calculated. Some trapping experiments with caffeic acid, and the acids mentioned above and using either t-cinnamic acid-3-[14C] or p-coumaric acid-2-[14C] as precursor, are discussed. A HPLC method for the rapid determination of phenolic acids in plant extracts, is described. 相似文献
69.
70.
Jakob Parzefall Jacques P. Durand Bernard Richard 《Ethology : formerly Zeitschrift fur Tierpsychologie》1980,53(2):133-138
The chemical communication of the epigean Necturus maculosus and the cave-living Proteus anguinus are compared in laboratory conditions. In both species a specks-specific substance transferred by water could be shown, another was deposited on the substrate. 相似文献