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The iron-sequestration explanation is the authors’ inference from the pattern of protection, not a direct measurement of free iron.\nexposure: 100% oxygen at 2.5 ATA for three 20-minute periods\nevidence_span: {\"source_cache\": \"artifacts/hbot-research/11023535.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"19b770dff3d327e2dd6d49180686f9823624190ab5693c28b88adcfaf703f14d\", \"start_char\": 0, \"end_char\": 1576, \"text_sha256\": \"19b770dff3d327e2dd6d49180686f9823624190ab5693c28b88adcfaf703f14d\"}\n[hbot-p11023535] Induction of heme oxygenase-1 and adaptive protection against the induction of DNA damage after hyperbaric oxygen treatment. 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