In the bird embryo these bristles erupt from tiny patches of skin cells called placodes. A ring of fast-growing cells on the top of the placode builds a cylindrical wall that becomes a bristle.

鸟胚中的刚毛结构来自于被称为基板（placode）的微小皮肤细胞结构，基板顶端快速增殖的细胞环形成了刚毛的圆柱井结构。

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An ancient magazine photograph of some dark-haired movie star was taped to the wall beside the bed, the skin tone gone magenta.

床边贴着一些从旧杂志上剪下来的照片，照片上那些黑头发的电影明星，都已经褪色发黄。

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The outer skin of the external wall is firmly connected with the overall building through its monolithic tie to the lower floors.

外壁的外皮被牢固地与整体连接，以较低楼层的建筑物整体连接。

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"The first several layers of the skin are like a castle wall protecting the athlete from outside marauders, " Adams says.

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Worms can get through the intestinal wall and move around under skin tissues.

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When a stray bomb hit the south wall of the citadel, sending up clouds of smoke and ash and shattering bits of rubble into his skin, his heart should have stopped.

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