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It is an in vitro enzyme study, so it does not exclude accumulation or amplification in a living tissue.\nexposure: Aspirin acetylation with arachidonic, eicosapentaenoic and docosahexaenoic acid as substrates\nevidence_span: {\"source_cache\": \"artifacts/aspirin-research/20194532.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"09427e18078449741ea9ea42dc91a16f50ca9f604ec05c4decbb255731104eaf\", \"start_char\": 0, \"end_char\": 1441, \"text_sha256\": \"09427e18078449741ea9ea42dc91a16f50ca9f604ec05c4decbb255731104eaf\"}\n[asa-p20194532] Asymmetric acetylation of the cyclooxygenase-2 homodimer by aspirin and its effects on the oxygenation of arachidonic, eicosapentaenoic, and docosahexaenoic acids. 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