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Zusammenfassung Es wird gezeigt, dass die Verteilung von Glukosaminoglykane in der Hühneraorta offenbar im Unterschied zu menschlichem Aortengewebe in Abhängigkeit der topographischen Lage steht. Höchste Gesamtwerte für Glykosaminoglykan wurden in der Brustaorta, niedrigste in der abdominalen Aorta gefunden. 相似文献
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Susan Tolnai 《Cellular and molecular life sciences : CMLS》1973,29(2):217-219
Résumé Etude des effects des sérums antilymphocytes sur la phagocytose in vitro par les macrophages de la rate et du péritoine de la souris. L'inhibition partielle de la phagocytose a été transitoire; les cellules macrophages ont récupéré leur capacité fonctionelle deux jours après l'administration de sérum antilymphocyte. 相似文献
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Summary The well defined circadian rhythms of glycogen content in heart, diaphragm and liver of the rat are drastically altered by a high lipid diet as shown by changes in amplitude, phase and tissue glycogen levels. If sampling times had been restricted to certain hours of the day the profound effect of the high fat diet on tissue glycogen would not have been apparent.Supported by USPHS grants HL 16041-03 and HL 07094-03. 相似文献
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R Sanchis-Ojeda DC Fabrycky JN Winn T Barclay BD Clarke EB Ford JJ Fortney JC Geary MJ Holman AW Howard JM Jenkins D Koch JJ Lissauer GW Marcy F Mullally D Ragozzine SE Seader M Still SE Thompson 《Nature》2012,487(7408):449-453
The Sun's equator and the planets' orbital planes are nearly aligned, which is presumably a consequence of their formation from a single spinning gaseous disk. For exoplanetary systems this well-aligned configuration is not guaranteed: dynamical interactions may tilt planetary orbits, or stars may be misaligned with the protoplanetary disk through chaotic accretion , magnetic interactions or torques from neighbouring stars. Indeed, isolated 'hot Jupiters' are often misaligned and even orbiting retrograde. Here we report an analysis of transits of planets over starspots on the Sun-like star Kepler-30 (ref. 8), and show that the orbits of its three planets are aligned with the stellar equator. Furthermore, the orbits are aligned with one another to within a few degrees. This configuration is similar to that of our Solar System, and contrasts with the isolated hot Jupiters. The orderly alignment seen in the Kepler-30 system suggests that high obliquities are confined to systems that experienced disruptive dynamical interactions. Should this be corroborated by observations of other coplanar multi-planet systems, then star-disk misalignments would be ruled out as the explanation for the high obliquities of hot Jupiters, and dynamical interactions would be implicated as the origin of hot Jupiters. 相似文献
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Lee JW Beebe K Nangle LA Jang J Longo-Guess CM Cook SA Davisson MT Sundberg JP Schimmel P Ackerman SL 《Nature》2006,443(7107):50-55
Misfolded proteins are associated with several pathological conditions including neurodegeneration. Although some of these abnormally folded proteins result from mutations in genes encoding disease-associated proteins (for example, repeat-expansion diseases), more general mechanisms that lead to misfolded proteins in neurons remain largely unknown. Here we demonstrate that low levels of mischarged transfer RNAs (tRNAs) can lead to an intracellular accumulation of misfolded proteins in neurons. These accumulations are accompanied by upregulation of cytoplasmic protein chaperones and by induction of the unfolded protein response. We report that the mouse sticky mutation, which causes cerebellar Purkinje cell loss and ataxia, is a missense mutation in the editing domain of the alanyl-tRNA synthetase gene that compromises the proofreading activity of this enzyme during aminoacylation of tRNAs. These findings demonstrate that disruption of translational fidelity in terminally differentiated neurons leads to the accumulation of misfolded proteins and cell death, and provide a novel mechanism underlying neurodegeneration. 相似文献