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A rat study.\nexposure: R-ibuprofen and R-ring-2H4;2-2H ibuprofen at 7.5 milligrams per kilogram each, given orally together\nevidence_span: {\"source_cache\": \"artifacts/ibuprofen-research/1676645.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"84a6a246386fa4fee28b69fb088aa21f2bc496addf424bd1c03c64eeaf159543\", \"start_char\": 0, \"end_char\": 1438, \"text_sha256\": \"84a6a246386fa4fee28b69fb088aa21f2bc496addf424bd1c03c64eeaf159543\"}\n[ibu-p1676645] Mechanistic studies on the metabolic chiral inversion of R-ibuprofen in the rat. (1991). https://pubmed.ncbi.nlm.nih.gov/1676645/ DOI: 10.1016/s0090-9556(25)07135-1","model_system":"Deuterium labelling with stereoselective gas chromatography and mass spectrometry in male Sprague-Dawley rats","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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