But knowing what percentage this is of the total amount leaking from the well will not be possible until a tight seal is on the well.

VOA: standard.2010.06.14

That's how tight the junctions are, not even a small molecule like glucose can pass between them.

可见胞间连接多么紧密,甚至像葡萄糖这样小的分子也不能通过

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