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161.
Steininger Andreas Lechthaler Mirjanka Pichler Heinrich 《e & i Elektrotechnik und Informationstechnik》1998,115(6):340-341
Ohne Zusammenfassung 相似文献
162.
Maike Timm‐Heinrich Xuebing Xu Nina Skall Nielsen Charlotte Jacobsen 《European Journal of Lipid Science and Technology》2003,105(8):436-448
Traditional sunflower oil (SO), randomized lipid (RL) and specific structured lipid (SL), both produced from SO and tricaprylin/caprylic acid, respectively, were stored for up to 12 wk to compare their oxidative stabilities by chemical and sensory analyses. Furthermore, the effect of adding a commercial antioxidant blend Grindox 117 (propyl gallate/ citric acid/ascorbyl palmitate) or gallic acid to the SL was investigated. The lipid type affected the oxidative stability: SL was less stable than SO and RL. The reduced stability was most likely caused by both the structure of the lipid and differences in production/ purification, which caused lower tocopherol content and higher initial levels of primary and secondary oxidation products in SL compared with RL and SO. Grindox 117 and gallic acid did not exert a distinct antioxidative effect in the SL oil samples during storage. 相似文献
163.
Electron spectroscopic imaging (ESI) was used to analyze the element content of melanin granules in the stria vascularis seen in ultrathin sections of Spurr-embedded cochleae of the guinea pig. To determine element composition, ESI images were taken at different ionization edges, and non-specific background signals were subtracted digitally by an image processing system. The presence of calcium and nitrogen in the melanin granules could be demonstrated clearly. The calcium identified in the melanin granules was then compared with the spatial distributions of calcium binding sites after the application of an antimonate precipitation method, which was used to localize loosely bound calcium. Despite a high calcium concentration within the granules, only very small single scattered calcium precipitates could be detected between these structures as compared with the amount of calcium precipitates attached to the plasma membrane or located within the cell nuclei. The nearly complete absence of precipitates within the melanin granules after the application of antimonate suggests differences in calcium binding and mobility involved in various physiological processes of ion balance regulation within the stria vascularis. 相似文献
164.
165.
D Rogoff Z Smolenicka I Bergadá G Vallejo M Barontini JJ Heinrich P Ferrari 《Canadian Metallurgical Quarterly》1998,83(12):4391-4393
In the kidney, the 11beta-hydroxysteroid dehydrogenase type 2 enzyme (11betaHSD2) inactivates glucocorticoids to their inactive ketoforms and thus prevents endogenous glucocorticoids from occupying the nonselective mineralocorticoid receptor in epithelial tissues. Several mutations have been described in the 11betaHSD2 gene in the congenital syndrome of apparent mineralocorticoid excess. These mutations generate partially or completely inactive 11betaHSD2 enzymes. In the present work, we describe an already known mutation in a new patient affected by apparent mineralocorticoid excess, which results in an arginine-to-cysteine mutation (R213C) in the 11betaHSD2 enzyme. This mutation has been found in two other independent families. In vitro expression studies of this mutant provide evidence that the mutant protein is normally expressed, but its activity is abolished. The CGC-to-TGC (C-toT) transition at codon 213 can be considered a typical CpG-consequence mutation. The present finding suggests that the codon R213 of 11betaHSD2 is a hot spot for mutations in this gene, as shown by the occurrence of an R213C point-mutation in several families unrelated to each other. 相似文献
166.
Ohne ZusammenfassungDie Anregung zu dieser Abhandlung gaben lebensmittelrechtliche Veröffentlichungen von Herrn Oberlandesgerichtspräsidenten i. R. Dr. jur. H. Holthöfer, dem ich für wertvolle Hinweise bei der Durchsicht des Entwurfes dieser Arbeit zu Dank verpflichtet bin. 相似文献
167.
Atomanordnung in der σ-Phase. Magnetisches Verhalten der FeV- und FeCr-σ-Phase bei tiefen Temperaturen. Konzentrationsabhängigkeit der Curietemperaturen. 相似文献
168.
169.
Summary This paper presents a theoretical investigation of SANS from labeled chains in polymer networks which are characterized by the topology of tube-like deformation dependent configurational constraints. The deformation dependence of the constraints is assumed to relax and to be determined by a microscopic deformation law. The results lead to the conclusion that the change of the radius of gyration of a network chain may be much less than the deformation of the macroscopic sample. It is pointed out that network defects favour the effect of constraint release. 相似文献
170.