Another 3 aliquots of blood were taken from the individuals for the study of intraindividual biological variations.

再自每名志愿者抽取另外3份血样，用于生物学变异试验。

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Another 3 aliquots of blood, each at an interval of 1 week, were taken from the individuals for the study of intraindividual biological variations.

再自每名志愿者抽取另外3份血样，每份间隔1周，按规定进行样品处理，用于生物学变异试验；

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