左旋分子就是使偏振光发生左(即逆时针方向)旋的分子。

A left-handed molecule is one that causes polarised light to rotate to the left (ie, anticlockwise).

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左：机器人向左旋转90度，并保持原先所在的格网位置不变。

Left: the robot turns left 90 degrees and remains on the current grid point.

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组间比较两组1个月随访时在颈椎前屈、左屈、右屈、左旋、右旋5个方向的活动度变化值均有统计学意义（P<0.05）。

Compared between groups, cervical anteflexion, left and right lateral bending, left and right rotative activity showed significant difference at the 1 month after treatment(P<0.05).

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The drug L-DOPA increases the supply of dopamine and so there is something to alleviate, at least temporarily, the symptoms of Parkinson's.

左旋多巴这种药可以增加多巴胺的分泌量,所以这种药物,至少可以暂时性地缓解,帕金森症的症状

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