Cell lineage the theory stating that cells arise only from pre-existing cells.

细胞谱系：该理论起始于细胞仅仅产生于已经存在的细胞。

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After completing the above steps, you will have created a new V6 cell whose deployment manager manages all the pre-existing V5 nodes.

在完成以上的步骤之后，您就新建了一个版本6的单元，该单元的部署管理器管理着所有先前存在的版本5的节点。

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In 2001, President George W. Bush banned all federal funding for human embryonic stem cell research, except on a handful of "pre-existing" stem cell lines.

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