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Summary The trace element content of a few Swiss ophiolites, radiolarian cherts and marls has been determined by means of spectrographic methods.Field observations, microscopical and spectrographical data lead to the conclusion that the colour of green cherts in certain areas is due to the supply of clastic peridotite- and serpentine-particles originating from a syn-temporaneous ultrabasic igneous body. 相似文献
143.
Ohne Zusammenfassung 相似文献
144.
Th. Cooper M. Jellinek Teresa Pinakatt A. W. Richardson 《Cellular and molecular life sciences : CMLS》1965,21(1):28-29
Résumé L'administration intraveineuse de pyridoxine et pyridoxal (10 mg/kg) à des rats anesthésiés inhibe l'augmentation du rendement du cocur. En même temps, une hyperthermie est provoquée par l'irradiation du corps entier avec des ondes de longueur minime (2,450 Mc. c.w. 0.08/w/cm2). Cet effet peut être attribué à l'interaction de ces composés d'amines vasoactifs libérés pendant l'irradiation. 相似文献
145.
G.Krabbes P.Diko C.Wende Th.Hopfinger G.Fuchs 《清华大学学报》2003,8(3):251-265
We have investigated the phase equilibria in (RE)BaCuO/Ag systems, the influence of Ag on the processing of (RE)BaCuO/Ag composites and the resulting properties. YBaCuO/Ag composites have been grown by the modified melt crystallization process with YBa2Cu3O7, Y2O3, Pt and Ag2O in the precursor. The improved strength of the YBaCuO/Ag composites compared with the conventional YBaCuO bulk material permitted us to magnetize these materials to achieve trapped fields up to 16 T (at 24 K) in the gap of a mini-magnet. The investigation of the microstructure revealed a remarkable increase of the spacing between micro-cracks especially of those perpendicular to a/b-planes when 12wt% Ag was added. In the case of SmBaCuO/Ag composites, Ag has a strong influence on processing and causes interactions between RE123 seeds and the sample. We show the growth of single-grain SmBaCuO/Ag composites in air and discuss the influence of post-annealing on increasing Tc and Jc. Furthermore, YBaCuO/Ag composites have been shown to be appropriate materials used as a solder to join large single grains to large arrays or to “repair” grain boundaries in arrays grown by a multiseeding technique. 相似文献
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Summary Two h of nerve stimulation at 10 Hz or of elevated spontaneous release in hypertonic solution increased the size of miniature end-plate potentials (m.e.p.p.'s) and currents at the frog neuromuscular junction, probably by increasing the amount of acetylcholine in a quantum. Increases in quantal size may modulate synaptic transmission.Acknowledgments. Supported by grant 10320 from the NINCDS and by a grant from the MDA. We are grateful to Dr I.S. Cohen for participating in some of the experiments and for helpful criticism, and to Drs C. Clausen and G. Baldo for help with the computer. Some of the results were presented at a meeting of the Physiological Society. 相似文献
148.
D. E. Champagne J. Th. Arnason B. J. R. Philogène G. Campbell D. G. McLachlan 《Cellular and molecular life sciences : CMLS》1984,40(6):577-578
Summary Alpha-terthienyl, a phototoxic thiophene derivative from species in the Asteraceae reduced feeding and growth of the phytophagous lepidopteran,Euxoa messoria, when incorporated into artificial diets at a concentration of 100 ppm. The effects of this substance were substantially enhanced by including photosensitizing near-UV radiation in the trials. The results suggest that the phototoxic properties of this secondary substance provide significant protection to the plants containing it.This work was supported by NSERC and Agriculture Canada. 相似文献
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Dr. J. B. Rognoni Th. Lemarchand-Béraud C. Berthier 《Cellular and molecular life sciences : CMLS》1984,40(2):215-217
Summary After a 6-month iodide deficiency, Wistar male rats were submitted to a normal iodine diet (20 and 50 g of127I daily). Plasma T3, T4 and TSH were determined by RIA from 0 to 140 days of iodide refeeding. A highly significant correlation was found between plasma TSH and T4 concentrations, but not between plasma TSH and T3 levels. These data suggest that an increase in plasma T3 alone, up to the normal value, is not able to inhibit TSH secretion. It is only when a certain plasma T4 concentration is also reached, resulting in further T3 formation through deiodination, that TSH secretion is inhibited.Dedicated to the memory of Prof. C. Simon.This work was supported by grants from the CNRS (Equipe de Recherche Associée no 234) and from the INSERM (A.T.P. 49.77.8).Acknowledgments. The authors wish to thank Mrs M. Chartier for valuable technical assistance. They are indebted to the rat pituitary distribution programme of NIAMDD, NIH, Bethesda, for their gift of rat TSH reagents. 相似文献