They often involve the generation of what are called 'second messenger' molecules which carry the signal further into the cell.

过程中通常会生成一种叫做,第二信使的分子,将信号更深入地传递至细胞内部

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This is another example of a second messenger, the inositol lipid pathway.

这是另一个第二信使的例子,磷酸肌醇信号通路

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