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1·Then they amputated a small piece from each flatworm.

然后他们把每个涡虫切成小块。

2·The flatworm relies upon a population of stem cells to accomplish this remarkable feat;

扁形虫（涡虫是一种扁形虫）要靠大量的干细胞才能完成这种非凡的技艺；

3·After all, the flatworm planaria does just fine with eyes that are arguably not as good.

从上可知，扁形涡虫的眼睛比理论上要好得多。

4·A planarian is a flatworm, one of the lowest life-forms that can be considered an animal.

真涡虫是一种扁虫，一种可以被认为是动物的最低级生命形式。

5·The tiny flatworm Planaria can be cut into as many as 32 pieces, each of which will grow into a whole new animal complete with eyes, mouth and internal organs.

涡虫类扁虫能被切成三十二片，而每一片都会长成一只全新的动物，眼睛、嘴和内脏俱全。

6·Somewhere in the middle may be schistosomiasis, a debilitating disease caused by a parasitic flatworm carried by water snails, which affects 200m people worldwide.

居于这些层次中间的可能是血吸虫病，一种由寄生于钉螺的扁平虫引起的影响患者健康的疾病，它影响着世界上2亿左右的人口。