The one snag on the lander happened when the protective sheath around the robotic arm didn't unwrap all the way after touchdown.

唯一的故障就是在探测器着陆后包围机械手臂的保护罩始终没能打开。

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The spiral protective sheath for the rubber tube with good elasticity is more in favor of being installed outside an oil pipe, and has longer service life.

月牙结构，相对传统的 特别加厚和直板技术，也更加富有弹性。弹性好的胶管螺旋保护套更有利于安 装在油管外面，且寿命更长。

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The device can also include a protective sheath disposed over at least a portion of the elongate shaft and movable relative to the elongate shaft between a distal position and a proximal position.

该设备还包 含置于细长轴的至少一部分上的保护套，且可相对于细长轴在远 端位置和近端位置上移动。

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One is a protective sheath that keeps cells alive for months outside a host body, nourished by a layer of fat.

FORBES: The Science of Small

In MS, the protective sheath or layer around nerves, called myelin, comes under attack which, in turn, leaves the nerves open to damage.

BBC: Simple eye scan can reveal extent of Multiple Sclerosis

With MS, the protective layer around nerves, known as the myelin sheath, becomes damaged.

BBC: Brain scan of MS patient