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排序方式: 共有453条查询结果,搜索用时 234 毫秒
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Maria P. Ikonomopoulou Yaiza Lopez-Mancheño Marta G. Novelle Maite Martinez-Uña Lahiru Gangoda Martin Pal Luis Filipe Costa-Machado Pablo Jose Fernandez-Marcos Grant A. Ramm Manuel Alejandro Fernandez-Rojo 《Cell reports》2021,34(11):108851
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E Santiago N López-Moratalla M J López-Zabalza A J Iriarte J Huamán 《Revista Espanola de Fisiología》1979,35(2):201-207
A series of uncouplers and inhibitors of oxidative phosphorylation have been studied with regard to their effect on the hydrolytic activity of the reduced and oxidized forms of isolated or membrane-bound mitochondrial ATPase. Uncouplers (2,4-dinitrophenol, dicoumarol), which are also activators of the hydrolytic activity of ATPase, were more potent activators on the oxidized form of the enzyme. Inhibitors of oxidative phosphorylation (oligomycin, azide and amytal) had a more potent inhibitory effect on the hydrolytic activity of ATPase in its reduced form. Purified F1-ATPase, oligomycin insensitive in the oxidized form of the enzyme, became sensitive to oligomycin in the reduced form. An interpretation of the results suggests the presence of a mechanism that unifies the action of these different compounds on the synthesis and hydrolysis of ATP catalyzed by mitochondrial ATPase. 相似文献
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A simple solution for antibody signal enhancement in immunofluorescence and triple immunogold assays 总被引:1,自引:0,他引:1
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Dawrin Pech-Puch Honorio Cruz-López Cindy Canche-Ek Gabriela Campos-Espinosa Elpidio García Maite Mascaro Carlos Rosas Daniel Chávez-Velasco Sergio Rodríguez-Morales 《PloS one》2016,11(2)
Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod. The water extract was fractionated by membrane ultrafiltration with a molecular weight cut-off of 3kDa leading to a metabolic phase (>3kDa) and a neurotoxic fraction (<3kDa). The neurotoxic fraction injected in the crabs caused paralysis and postural changes. Crabs recovered to their initial condition within two hours, which suggests that the effects of the neurotoxic fraction were reversible. The neurotoxic fraction was also active on O. maya conspecifics, partly paralyzing and sedating them; this suggests that octopus saliva might be used among conspecifics for defense and for reduction of competition. Bioguided separation of the neurotoxic fraction by chromatography led to a paralysis fraction and a relaxing fraction. The paralyzing activity of the saliva was exerted by amino acids, while the relaxing activity was due to the presence of serotonin. Prey-handling studies revealed that O. maya punctures the eye or arthrodial membrane when predating blue crabs and uses the radula to bore through crown conch shells; these differing strategies may help O. maya to reduce the time needed to handle its prey. 相似文献
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Effect of sensitization on somatostatin concentration and binding in cytosol from guinea pig airways
V Barrios M C Fernandez Iriarte E Morcillo J C Prieto E Arilla 《Regulatory peptides》1987,19(3-4):161-168
In guinea pigs sensitized with 1 microgram ovalbumin together with 100 mg Al(OH)3, somatostatin levels were selectively increased up to two and 3 times in tissue extracts from trachea and bronchi, respectively, but not in lung as compared to controls. The increase of somatostatin levels observed in trachea and bronchi after sensitization was associated with a decrease in the binding capacity of both high- and low-affinity binding sites (without changes in the affinity values) in the corresponding cytosolic fractions. These results suggests that an increase in airways somatostatin content may be involved in the pathogenesis of anaphylactic bronchoconstriction. 相似文献