In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.

Q: Plasma prolactin in patients with colorectal cancer .

A: Plasma prolactin
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Q: Indeed , after a single oral dose , the role of the mu - receptor agonist component of the antinociceptive effect of tramadol appears to be minor , with most of the analgesic effect being attributable to nonopioid properties of the parent compound .

A: mu - receptor
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Q: Patients in the mucinous cyst group had significantly lower CA 125 cystic fluid levels compared with women with endometriomas and dermoids ( P & lt ; 0 . 05 ) .

A:
CA 125
****