来自《耶鲁大学开放课程：生物医学工程探索 第17集 第17集》

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  Now, you have high sodium inside or higher than before
  现在 内部钠浓度高了 或者说比之前高了
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  because sodium can leak through these channels,
  因为钠能够通过这些通道渗透进去
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  but you have on this other surface of the cell,
  但在细胞的另一侧表面
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  you have a lot of these sodium potassium pumps.
  存在很多的钠钾泵
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  These sodium potassium pumps are constantly pumping sodium out
  这些钠钾泵不间断地将钠泵出来
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  and bringing potassium, sodium out, potassium in and there's pumps here,
  将钾泵进来 钠出去 钾进来 而这里有泵
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  there's pumps here, there's pumps here.
  这里有泵 这里也有
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  So, any molecules of sodium that enter this side
  因此 任何进入这一侧的钠离子
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  get efficiently pumped out through the other side.
  都被高效地从另一侧泵出去了
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  The net effect of these two processes,
  这两个过程的净效果是
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  diffusion on this boundary and active transport on this boundary,
  在这边的渗透和在这边的主动运输
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  is that sodium molecules move from inside the tube to outside the tube.
  使得钠离子从肾小管内向管外运动