翻訳と辞書 Words near each other ・ Refractor Engine ・ Refractories heat-up ・ Refractoriness under load ・ Refractory ・ Refractory (disambiguation) ・ Refractory (planetary science) ・ Refractory anemia with excess of blasts ・ Refractory anemia with ring sideroblasts ・ Refractory clergy ・ Refractory cytopenia of childhood ・ Refractory cytopenia with multilineage dysplasia ・ Refractory lined expansion joint ・ Refractory metals ・ Refractory Obdurate ・ Refractory period ・ Refractory period (physiology) ・ Refractory period (sex) ・ Refrain ・ Refrain (disambiguation) ・ Refrain (Lys Assia song) ・ Refrain (Mamoru Miyano song) ・ Refrain (Stockhausen) ・ Refrain Club ・ Reframe ・ Reframing (filmmaking) ・ Reframing time ・ Refrancore ・ Refrath Formation ・ Refrescante ・ Refresh Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Refractory period (physiology) ： ウィキペディア英語版 Refractory period (physiology) Refractoriness is the fundamental property of any object of autowave nature (especially excitable medium) not to respond on stimuli, if the object stays in the specific ''refractory state''. In common sense, refractory period is the characteristic recovery time, a period of time that is associated with the motion of the image point on the left branch of the isocline $\backslash dot\; =\; 0$〔 (for more details, see also Reaction-diffusion and Parabolic partial differential equation). In physiology,〔 a refractory period is a period of time during which an organ or cell is incapable of repeating a particular action, or (more precisely) the amount of time it takes for an excitable membrane to be ready for a second stimulus once it returns to its resting state following an excitation. It most commonly refers to electrically excitable muscle cells or neurons. Absolute refractory period corresponds to depolarisation and repolarisation, whereas relative refractory period corresponds to hyperpolarisation. == Electrochemical usage == After initiation of an action potential, the refractory period is defined two ways: The absolute refractory period coincides with nearly the entire duration of the action potential. In neurons, it is caused by the inactivation of the Na+ channels that originally opened to depolarize the membrane. These channels remain inactivated until the membrane hyperpolarizes. The channels then close, de-inactivate, and regain their ability to open in response to stimulus. The relative refractory period immediately follows the absolute. As voltage-gated potassium channels open to terminate the action potential by repolarizing the membrane, the potassium conductance of the membrane increases dramatically. K+ ions moving out of the cell bring the membrane potential closer to the equilibrium potential for potassium. This causes brief hyperpolarization of the membrane, that is, the membrane potential becomes transiently more negative than the normal resting potential. Until the potassium conductance returns to the resting value, a greater stimulus will be required to reach the initiation threshold for a second depolarization. The return to the equilibrium resting potential marks the end of the relative refractory period. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Refractory period (physiology)」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.