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71.
72.
Cervicofacial rhytidectomy 总被引:1,自引:0,他引:1
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Adenine derivatives and auxin-related compounds, 2,4-dichlorophenoxyaceticacid (2,4-D) and 2,3,5-triiodobenzoic acid (TIBA), did not inhibitthe transport systems for succinate or malate into mitochondria.In iso-osmotic KC1 medium, some of these compounds increasedion fluxes moderately. TIBA and 2,4-D inhibited the mitochondrialshrinkage induced by the substrates. In contrast, adenine derivativesinhibited only the shrinkage induced by the substrate whoseoxidation they were able to block specifically. (Received February 18, 1987; Accepted June 29, 1987) 相似文献
76.
Olivier Puel Souria Tadrist Pierre Galtier Isabelle P. Oswald Marcel Delaforge 《Applied microbiology》2005,71(1):550-553
Byssochlamys species are responsible for spoilage and degradation of fruits and silages and can also produce the mycotoxin patulin. We analyzed secondary metabolite production by Byssochlamys nivea. Mycophenolic acid and its precursors, 5-methylorsellinic acid and 5,7-dihydroxy-4-methylphthalide, were identified in all of the B. nivea strains that we examined. 相似文献
77.
Homologous and Heterologous Overexpression in Clostridium acetobutylicum and Characterization of Purified Clostridial and Algal Fe-Only Hydrogenases with High Specific Activities 下载免费PDF全文
Laurence Girbal Gregory von Abendroth Martin Winkler Paul M. C. Benton Isabelle Meynial-Salles Christian Croux John W. Peters Thomas Happe Philippe Soucaille 《Applied microbiology》2005,71(5):2777-2781
Clostridium acetobutylicum ATCC 824 was selected for the homologous overexpression of its Fe-only hydrogenase and for the heterologous expressions of the Chlamydomonas reinhardtii and Scenedesmus obliquus HydA1 Fe-only hydrogenases. The three Strep tag II-tagged Fe-only hydrogenases were isolated with high specific activities by two-step column chromatography. The purified algal hydrogenases evolve hydrogen with rates of around 700 μmol H2 min−1 mg−1, while HydA from C. acetobutylicum (HydACa) shows the highest activity (5,522 μmol H2 min−1 mg−1) in the direction of hydrogen uptake. Further, kinetic parameters and substrate specificity were reported. An electron paramagnetic resonance (EPR) analysis of the thionin-oxidized HydACa protein indicates a characteristic rhombic EPR signal that is typical for the oxidized H cluster of Fe-only hydrogenases. 相似文献
78.
Spatial heterogeneity of light penetration through periderm and lenticels and concomitant patchy acclimation of corticular photosynthesis 总被引:3,自引:0,他引:3
The hypothesis that lenticels may act as a gate for light penetration through the highly light absorptive periderm, was investigated. Yet, transmittance of isolated periderms from ten tree species was considerably higher in the non-lenticel than in the lenticel regions. Depending on species, the lower transmittance of lenticels was due to either higher reflectance and/or higher absorptance. Corticular tissue regions below lenticels were more shade acclimated. Chlorophyll fluorescence images showed lower PS II effective yields, a lower potential for non-photochemical quenching and a possibly higher risk of photoinhibition in the corticular areas under the lenticels in most of the cases. 相似文献
79.
Isabelle Leray Bernard Valeur Dharam Paul Emilie Regnier Matthieu Koepf Jennifer A Wytko Corinne Boudon Jean Weiss 《Photochemical & photobiological sciences》2005,4(3):280-286
Three self-assembled photonic dyads comprising a zinc porphyrin donor and a free base acceptor have been studied by time-resolved fluorescence spectroscopy. The driving force of the assembly is the site selective binding of an imidazole connected to a free base porphyrin. Three spacers have been incorporated between the imidazole connector and the free base porphyrin, providing three different distances separating the donor and the acceptor. The high efficiencies and the rates of energy transfer in the set of dyads is consistent with the Forster energy transfer mechanism. Evidence for Forster back transfer has been obtained, and its efficiency and rate have been quantitatively evaluated for the first time. 相似文献
80.
Fourier Transform Infrared and Raman Spectroscopy for Characterization of Listeria monocytogenes Strains 总被引:1,自引:0,他引:1 下载免费PDF全文
Astrid Oust Trond Mretr Kristine Naterstad Ganesh D. Sockalingum Isabelle Adt Michel Manfait Achim Kohler 《Applied microbiology》2006,72(1):228-232
The purpose of this study was to characterize the variation in biochemical composition of 89 strains of Listeria monocytogenes with different susceptibilities towards sakacin P, using Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy. The strains were also analyzed using amplified fragment length polymorphism (AFLP) analysis. Based on their susceptibilities to sakacin P, the 89 strains have previously been divided into two groups. Using the FTIR spectra and AFLP data, the strains were basically differentiated into the same two groups. Analyses of the FTIR and Raman spectra revealed that the strains in the two groups contained differences in the compositions of carbohydrates and fatty acids. The relevance of the variation in the composition of carbohydrates with respect to the variation in the susceptibility towards sakacin P for the L. monocytogenes strains is discussed. 相似文献