来自《耶鲁大学开放课程：生物医学工程探索 第15集 第15集》

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  and actually physically reprogram it,
  完全物理性的重新编程
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  so these are quite sophisticated engineering devices now.
  因此这些是非常复杂精密的生物工程装置
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  I said something about action potentials and ion currents.
  我已经讲过动作电位和离子通道
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  I'm not going to say anything more about that now.
  后面不再讨论了
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  I will say that in neurons what is important in
  我要说的是在神经细胞中
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  a propagation of an action potential is sodium and potassium,
  钠和钾对于生成动作电位至关重要
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  but in muscle cells calcium is also a much more important player.
  而在肌细胞中钙离子也扮有同样重要的角色
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  The reason that calcium is a much more important player is,
  你越往后面学习生理学
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  as you will learn if you study more physiology,
  你就会明白钙离子为何如此重要
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  calcium is the most important ion in terms of initiating contraction.
  钙离子对于启动收缩来说是最为重要的
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  So,movement of calcium around muscle cells is very important.
  因此 肌细胞周围的钙离子运动是非常重要的
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  This just shows an action potential in,
  这里展示了一个动作电位的传入