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881.
Résumé On a donné de la nicotine à des rats une fois par jour, pendant 10 jours. L'activité des animaux a d'abord diminué, mais après quelques administrations de la drogue, on constata une accoutumance à ces effets. L'administration terminée, l'activité a augmenté.
This work was supported by a grant from the Tobacco Research Council. 相似文献
This work was supported by a grant from the Tobacco Research Council. 相似文献
882.
883.
L. I. Larsson F. Sundler L. Grimelius R. Håkanson J. Holst 《Cellular and molecular life sciences : CMLS》1973,29(6):698-699
Zusammenfassung Glucagon ist durch Immunohisto-fluoreszenz in einem A2-Zell-Carcinom der menschlichen Bauchspeicheldrüse und in Metastasen in der Leber entdeckt worden.
Acknowledgments. Grant support from the Swedish Medical Research Council No. B73-04X-1007-08 and B73-12X-102-09B, Albert Påhlsson's Foundation, Riksföreningen mot Cancer, «Fonden för Stor-Köpenhamn, Grönland och Färöarna», and «Landsföreningen för kräftans bekämpelse». 相似文献
Acknowledgments. Grant support from the Swedish Medical Research Council No. B73-04X-1007-08 and B73-12X-102-09B, Albert Påhlsson's Foundation, Riksföreningen mot Cancer, «Fonden för Stor-Köpenhamn, Grönland och Färöarna», and «Landsföreningen för kräftans bekämpelse». 相似文献
884.
885.
886.
I. Kubo T. Matsumoto F. J. Hanke M. Taniguchi Y. Hayashi 《Cellular and molecular life sciences : CMLS》1985,41(11):1462-1463
Summary A possible new role for the flavonoid (–)-epicatechin (II) is described. It has no growth effects on its own, but when it is added to lettuce and rice seeds together with the known seedling growth inhibitor nagilactone E (I), the growth inhibitor activity ofI can cease and growth stimulation can be observed. 相似文献
887.
F. Weber 《Cellular and molecular life sciences : CMLS》1985,41(3):398-400
Summary Pieces of the hind legs of freshly moltedBlaberus craniifer adults were cultivated in vitro. The deposition of multilamellate and circadian-like layered endocuticle was observed. In multilamellate cuticle, the number of double lamellae was frequently much greater than the number of days in culture. In circadian-like layered cuticle, the number of double layers corresponded to the numbers of days in culture, or it was smaller.I am indebted to Mrs Hassenrück, for excellent assistance. — Supported by the Deutsche Forschungsgemeinschaft (We 389/12-2). 相似文献
888.
889.
Thyroid hormone controls carnitine status through modifications of γ-butyrobetaine hydroxylase activity and gene expression 总被引:1,自引:0,他引:1
Galland S Georges B Le Borgne F Conductier G Dias JV Demarquoy J 《Cellular and molecular life sciences : CMLS》2002,59(3):540-545
The carnitine system plays a key role in β-oxidation of long-chain fatty acids by permitting their transport into the mitochondrial
matrix. The effects of hypothyroidism and hyperthyroidism were studied on γ-butyrobetaine hydroxylase (BBH), the enzyme responsible
for carnitine biosynthesis in the rat. In rat liver, BBH activity was decreased in the hypothyroid state and increased in
hyperthyroid animals. The modifications in BBH activity correlated with changes in the enzyme Vmax values. These changes were
shown to be related to hepatic BBH mRNA abundance. Thyroid hormones are known to interact with lipid metabolism, in particular
by increasing long-chain fatty acid oxidation through activation of carnitine-dependent fatty acid import into mitochondria.
Our study showed that thyroid hormones also increased carnitine bioavailability.
Received 23 October 2001; received after revision 11 January 2002; accepted 15 January 2002 相似文献
890.
Van Waeyenberge B Puzic A Stoll H Chou KW Tyliszczak T Hertel R Fähnle M Brückl H Rott K Reiss G Neudecker I Weiss D Back CH Schütz G 《Nature》2006,444(7118):461-464
The vortex state, characterized by a curling magnetization, is one of the equilibrium configurations of soft magnetic materials and occurs in thin ferromagnetic square and disk-shaped elements of micrometre size and below. The interplay between the magnetostatic and the exchange energy favours an in-plane, closed flux domain structure. This curling magnetization turns out of the plane at the centre of the vortex structure, in an area with a radius of about 10 nanometres--the vortex core. The vortex state has a specific excitation mode: the in-plane gyration of the vortex structure about its equilibrium position. The sense of gyration is determined by the vortex core polarization. Here we report on the controlled manipulation of the vortex core polarization by excitation with small bursts of an alternating magnetic field. The vortex motion was imaged by time-resolved scanning transmission X-ray microscopy. We demonstrate that the sense of gyration of the vortex structure can be reversed by applying short bursts of the sinusoidal excitation field with amplitude of about 1.5 mT. This reversal unambiguously indicates a switching of the out-of-plane core polarization. The observed switching mechanism, which can be understood in the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application in data storage. 相似文献