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991.
In this work, we introduce new phenomenological neuronal models (eLIF and mAdExp) that account for energy supply and demand in the cell as well as the inactivation of spike generation how these interact with subthreshold and spiking dynamics. Including these constraints, the new models reproduce a broad range of biologically-relevant behaviors that are identified to be crucial in many neurological disorders, but were not captured by commonly used phenomenological models. Because of their low dimensionality eLIF and mAdExp open the possibility of future large-scale simulations for more realistic studies of brain circuits involved in neuronal disorders. The new models enable both more accurate modeling and the possibility to study energy-associated disorders over the whole time-course of disease progression instead of only comparing the initially healthy status with the final diseased state. These models, therefore, provide new theoretical and computational methods to assess the opportunities of early diagnostics and the potential of energy-centered approaches to improve therapies. 相似文献
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995.
Interactions of luciferases isolated from Vibrio fischeri 6 and Escherichia coli JM109(pF3) (bearing cloned V. fischeri luxAB genes) with FMN reductase isolated from E. coli JM109 were studied. FMN reductase formed a stable complex with luciferase, suggesting similar properties of the FMN reductases in the taxonomically close families Vibrionaceae and Enterobacteriaceae. 相似文献
996.
A G Chuchalin V A Babushkina V Ia Arion R D Aspetov T B Sha?khinova 《Biulleten' eksperimental'no? biologii i meditsiny》1984,98(7):76-78
A study was made of the effect of T-activin on the biosynthesis of immune gamma-interferon. It was shown that in 27% of patients with chronic nonspecific pulmonary diseases, production of gamma-interferon by lymphocytes was substantially reduced during exacerbation of inflammatory process in the lungs. It was discovered that T-activin was not an interferon inductor but enhanced its synthesis in patients with a low capacity of producing immune interferon even at small doses of interferon inductor. The preparation does not produce any effect on this process in normal subjects and in patients showing the normal level of gamma-interferon. Thus T-activin can be used for stimulation of interferonogenesis. 相似文献
997.
Gene frequencies and microdifferentiation among the Makiritare Indians. I. Eleven blood group systems and the ABH-Le secretor traits: a note on Rh gene frequency determinations. 总被引:11,自引:8,他引:3
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H Gershowitz M Layrisse Z Layrisse J V Neel C Brewer N Chagnon M Ayres 《American journal of human genetics》1970,22(5):515-525
998.
V S Pikaliuk 《Arkhiv anatomii, gistologii i émbriologii》1991,100(5):5-12
In the experiment performed on 175 white male rats by means of a complex of morphological, biochemical and biomechanical methods peculiarities of structure, growth, outline formation and mineralization of the skeletal bones have been investigated under a toxic lesion of the organism with pesticides (chlorophose and keltan) and at a simultaneous administration of antioxidants of various groups (tocopherol, ionol, sodium selenit). Osteotoxic effect of the pesticides, manifested as an inhibition of bone growth, as a disbalance of mineral saturation and their composition, as a decrease in indices of firmness is leveled by means of therapeutic doses of the antioxidants. The stabilizing effect of the antioxidant applied correlates to the manifestation of the pesticides osteotoxic effect, to the ability of their cumulation in the organism and is directly connected with the supposed mechanism of damaging effect to the organism and/or cell. The expressiveness of the toxic effect of the chemical poison, in its turn, is defined not only by the dose, mechanism and duration of the effect, but by age peculiarities of the organism and by functional state of its reactivity. When the poisons are applied for a long time, in order to level their osteotoxic effect, a multiple increase of therapeutic doses of the antioxidants and a combined potentiation of their effect are necessary. 相似文献
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