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.

Example Input:  Fetal Down syndrome was diagnosed by karyotyping of amniotic fluid cells .
Example Output: fluid

Example Input:  For the 30 cases of benign lesions of the GB , only in 12 cases was a low velocity blood flow signal found .
Example Output: blood

Example Input:  In newborn pigs , sympathetic nerves may attenuate hypertension - induced increases in blood flow to the cerebrum , but do not appear to affect flow to the rest of the brain .
Example Output:
blood

