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201.
202.
F. T. Llados 《Cellular and molecular life sciences : CMLS》1985,41(12):1551-1552
Summary Frog skeletal muscle incubated in vitro with the ionophore A23187 shows extensive morphological alterations. Myofilament disruption, presumably mediated by excess intracellular calcium, can be partially prevented by preincubating the muscle with inhibitors of prostaglandin synthesis and the lysosomal thiol protease inhibitor leupeptin.The author would like to thank Dr R. J. Walter for helpful comments and Ms V. Kriho for valuable technical assistance 相似文献
203.
R. K. Suarez 《Cellular and molecular life sciences : CMLS》1992,48(6):565-570
Resting and maximal mass-specific metabolic rates scale inversely with body mass. Small hummingbirds achieve the highest known mass-specific metabolic rates among vertebrate homeotherms. Maximal capacities for O2 and substrate delivery to muscle mitochondria, as well as mitochondrial oxidative capacities in these animals may be at the upper limits of what are structurally and functionally possible given the constraints inherent in vertebrate design. Such constraints on the evolutionary design of functional capacities may play an important role in determining the lower limits to vertebrate homeotherm size and the upper limits to mass-specific metabolic rate. 相似文献
204.
Summary Dynamics of increase of white myotomal muscle fibers of four species of freshwater teleosts (Salmo gairdneri, Pimephales notatus, Esox masquinongy andE. americanus vermiculatus) from three families (Salmonidae, Cyprinidae, Esocidae) representing a variety of maximum attainable sizes and growth rates, have been investigated. There are at least three major differences in these dynamics, and there appears to be an association between the ability of a fish species to attain large size (and grow fast) and its ability to recruit new fibers into this predominant tissue of the myotomal mass. 相似文献
205.
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207.
T. B. Bolton R. J. Lang T. Takewaki C. D. Benham 《Cellular and molecular life sciences : CMLS》1985,41(7):887-894
Summary Dispersal of the constituent cells of mammalian visceral and vascular smooth muscles has permitted recordings both of membrane currents under whole-cell voltage clamp, and of currents through single ionic channels using the patch-clamp technique. A rectangular depolarizing step applied to a single cell under voltage clamp yielded a net inward current followed by a net outward current in normal physiological solution. In isolated, inside-out patches of cell membrane a calcium- and potential-sensitive K channel (100 pS conductance) and a calcium-insensitive, potential-sensitive K+ channel (50 pS conductance) with slow kinetics have so far been identified and characterized. 相似文献
208.
I. Bryman A. Norström B. Lindblom 《Cellular and molecular life sciences : CMLS》1985,41(11):1446-1447
Summary Cervical specimens were obtained by needle biopsy in connection with caesarean section at term pregnancy. The preparations were superfused in an organ chamber and contractions were registered isometrically. Prostaglandin (PG) E2 and F2 inhibited spontaneous contractions. The stimulatory action of noradrenaline was not influenced by PGF2 but was reduced by PGE2 whereas both PGs abolished the excitatory effect of oxytocin. 相似文献
209.
Dr. L. H. Lazarus G. Gaudino V. Erspamer 《Cellular and molecular life sciences : CMLS》1986,42(7):822-823
Summary Parallel in vitro biassays using rat uterus and guinea pig large intestine tissues specific for the bombesin family of peptides, demonstrated that the bombesin-like peptides present in bovine milk can produce a dose-related response similar to bombesin and litorin. The bioactivity of this type of milk peptide appeared to be approximately 20–50% as active as the amphibian peptides. These data support the proposal that a bombesin immunoreactive peptide in milk contains bombesin bioactivity.supported in part by a NATO Fellowship and by the Fogarty International Center of the National Institutes of Health, Bethesda, MD, USA.supported by a grant from the Consiglio Nazionale delle Ricerche 相似文献
210.
Summary The elver is a developmental stage of the European eel Anguilla anguilla (L.). During its growth, relatively large numbers of new muscle fibers are formed in the lateral musculature. We investigated the origin of these fibers. They proved to originate from already existing fibers by budding. 相似文献