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991.
992.
Nikolay Kutuzov Alexander Gulin Vladimir Lyaskovskiy Victor Nadtochenko Georgy Maksimov 《PloS one》2015,10(11)
In the present paper we addressed a mechanism of the myelin reorganization initiated by extracellular ATP and adenosine in sciatic nerves of the frog Rana temporaria. In combination with Raman microspectroscopy, allowing noninvasive live-cell measurements, we employed time-of-flight secondary ion mass spectrometry (TOF-SIMS) to follow the underlying changes in chemical composition of myelin membranes triggered by the purinergic agents. The simultaneous increase in lipid ordering degree, decrease in membrane fluidity and the degree of fatty acid unsaturation were induced by both ATP and adenosine. Mass spectrometry measurements revealed that ATP administration also led to the marked elevation of membrane cholesterol and decrease of phosphotidylcholine amounts. Vesicular lipid transport pathways are considered as possible mechanisms of compositional and structural changes of myelin. 相似文献
993.
994.
Victor v. Janka 《Plant Systematics and Evolution》1868,18(5):163-163
Ohne Zusammenfassung 相似文献
995.
996.
997.
Dr. Victor Schiffner 《Plant Systematics and Evolution》1896,46(3):82-88
Ohne Zusammenfassung 相似文献
998.
Trevor J. Douglas Victor M. Villalobos Michael R. Thompson Trevor A. Thorpe 《Physiologia plantarum》1982,55(4):470-477
Cotyledon explants of radiata pine contain principally lipid and protein reserve materials, which decline during shoot initiation. This process was followed phytochemically and ultrastructurally. Fatty acid and sterol analyses indicated that there were both quantitative and qualitative changes in the different classes of lipid. The most pronounced changes were an increase in the linolenic acid content of the polar lipids and the appearance of stigmasterol during shoot initiation. There was also a continued increase in chlorophyll and carotenoid levels, which paralleled chloroplast development. It appears that the changes observed were similar to those that occur in cotyledons during normal seedling development. 相似文献
999.
Summary A new apparatus is described which permits pure cultivation of 110 l amounts of phototrophic organisms. Some data are given to prove its utility for mass production (kilogram amounts) of algae and photosynthetic bacteria. 相似文献
1000.
Kenji Adachi Hajime Iizuka Kenneth M. Halprin Victor Levine 《Biochimica et Biophysica Acta (BBA)/General Subjects》1977,497(2):428-436
The cyclic AMP level in pig skin (epidermis) increases markedly after incubation with epinephrine, prostaglandin E, histamine or adenosine 5′-monophosphate. This increase is transient and “spiking” is the consistent response to these four stimulators. The “spiking” is due to a non-responsiveness or refractoriness which develops within minutes and is specific to any one stimulating hormone but not to the others. The addition of inhibitors of protein syntheses did not prevent the development of the refractoriness. Adenylate cyclase and phosphodiesterase activities measured in skin homogenates prepared from skin samples taken before, during and after the “spiking” did not change significantly. The hormone-induced refractoriness in this skin system appears to be due to a specific, localized loss of function of the adenylate cyclase system. 相似文献