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Exosomes: Generation, structure, transport, biological activity, and diagnostic application
Biochemistry (Moscow) Supplement Series A: Membrane and Cell Biology, 2016Cells of almost all tissues secrete to the extracellular environment a variety of vesicular structures. The most interesting vesicles are exosomes–microvesicles ranging from 30 to 100 nm in size. These vesicles contain various RNA, including mRNA, microRNA, as well as membrane and cytoplasmic proteins that can be transported in these particles to ...
S. N. Tamkovich +2 more
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Optimal control of active transport across a biological membrane
Artificial Life and Robotics, 1998We propose an optimal control principle for active transport across a biological membrane. The modeling of the membrane is based on Hill and Kedem's thermodynamic model. The performance function used to evaluate the optimality of the transport involved the rate of time-dependent changes in the concentration of particles in all the membrane layers as ...
Hirohumi Hirayama +2 more
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The theory of transport phenomena in biological membranes. II. The active transport of ions
Biochimica et Biophysica Acta (BBA) - Biomembranes, 1970Abstract A model is suggested coupling the processes of the passive and active transport of the Na + and K + in biological membranes. It is shown that the mechanism of active transport has features common to the mechanism of passive transport. However, it differs in the driving force maintaining the directed flow of ions.
M V, Volkenstein, S N, Fishman
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Active Transport in Biological Membranes and Stochastic Resonances
Physical Review Letters, 1997The role of intrinsic fluctuations of the membrane electric potential (barrier height) in the active transport of ions through cell membranes is examined. Experimental data [D.-S. Liu et al., J. Biol. Chem. 265, 7260 (1990)] on active transport of ${\mathrm{Na}}^{+}$ in human erythrocytes under the influence of ac electric fields can be interpreted as ...
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Transport of Biologically Active Interferon-gamma Across Human Skin in Vitro
Pharmaceutical Research, 1995Several studies have suggested epidermal uptake of cytokines, such as interferons, can be facilitated using topical liposomal formulations. We have evaluated the in vitro transport of biologically active recombinant human interferon-gamma (rhIFN-gamma) into and through split-thickness human skin to assess this possibility.Skin samples were exposed to ...
S M, Short +3 more
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Noise-stimulated active transport in biological cell membranes
Physics Letters A, 1994Abstract We show that existing experimental data on active transport of ions in living biological cells can be interpreted in terms of the transfer of energy from the stochastic field (fluctuations of membrane potential), and propose a method of further experimental verification of this interpretation.
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Mathematical theory of biological periodicities II. Effect of active transport
The Bulletin of Mathematical Biophysics, 1969A previous study (Bull. Math. Biophysics,30, 735–749) is generalized to the case of active transport, which acts together in general with ordinary diffusion. The basic results obtained are the same except for an additional important conclusion. In principle it is possible to obtain sustained oscillations even when the secretions of the different glands
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Immobilization of active facilitated glucose transporters (GLUT-1) in supported biological membranes
Applied Biochemistry and Biotechnology, 1997Membrane fragments or membrane proteins within a lipid mixture were immobilized over metal electrodes. This procedure has been developed to study biological membranes without interference from cell machinery. To obtain a smooth hydrophilic biomembrane support and a mode of binding of the membrane, either a crosslinked gel or an aromatic polyamine ...
C, Neumann-Spallart +2 more
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Modeling large-scale cohesive sediment transport affected by small-scale biological activity
Estuarine, Coastal and Shelf Science, 2008Biological activity on the bottom of the seabed is known to have significant influence on the dynamics of cohesive sediment on a small spatial and temporal scale. In this study, we aim to understand the large-scale effects of small-scale biological activity.
Borsje, Bastiaan Wijnand +3 more
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The mutual binding exclusion mechanism in active transport across biological membranes
Cell Biophysics, 1987The coupling mechanism of sarcoplasmic reticulum ATPase is based on the reciprocal influence of calcium binding and phosphorylation domains. Cooperative calcium binding activates the enzyme, permitting utilization of ATP by transfer of its terminal phosphate to the enzyme.
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