In this task, you are given a sentence. You are expected to write the name of the organism substances in the body mentioned in the input. Although there might be several correct answers, you need to write one of them.
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Question:  In our future studies in this population , we will collect larger volumes of serum for dioxin analysis .

Answer: serum


Question:  Differences between pigs of the innervated and denervated groups were not apparent , with respect to blood flow to any other region ( caudate region , brain stem , cerebellum ) .

Answer: blood


Question:  Archived serum collected near the time of the accident was used to measure exposures .

Answer:
serum