First of all, control experiments were carried out to investigate the influence of low level laser irradiation on oxygen dissociation curve of red blood cell, and on oxygenating process of blood.

首先，通过进行对照实验研究了弱激光的照射对血液的氧合过程和红细胞氧解离曲线的影响。

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But luckily we had the control of the red laser pointer where nothing moved at all.

但是很幸运我们可以,控制红色激光笔,虽然什么都没有移动。

麻省理工公开课 - 化学原理课程节选