氟化钠组根面亦可见明显的划痕，暴露的牙本质小管部分被封闭，在根面可见大小不一散在的指状结构；

NaF group also had significant root surface scratches, exposed dentinal tubules were partially closed and scattered finger-like structures are also visible on the root surface;

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下唇：一种唇状结构，如组成某些无脊柱动物的下唇基节，尤指昆虫。

A liplike structure, such as that forming the floor of the mouth of certain invertebrates, especially insects.

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任一种真菌，尤指珊瑚菌属，其经常色彩鲜艳的孢子结构呈球棒状或盘错枝叉状，形似珊瑚。

Any of numerous fungi, especially of the family Clavariaceae, whose often brightly colored spore-bearing structures are club-shaped to intricately branched and resemble coral.

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