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Antibody-based detection, so absence of signal is weaker evidence than presence.\nexposure: Anti-PDE1 and anti-PDE5 antibodies with functional testing, and sildenafil against sodium nitroprusside on platelets\nevidence_span: {\"source_cache\": \"artifacts/sildenafil-research/10078537.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"dceb60af4400fe67b4ffaf73a0aadb8d2e5fad0966b3372a3e46a91c0e0ccee5\", \"start_char\": 0, \"end_char\": 2610, \"text_sha256\": \"dceb60af4400fe67b4ffaf73a0aadb8d2e5fad0966b3372a3e46a91c0e0ccee5\"}\n[sil-p10078537] Tissue distribution of phosphodiesterase families and the effects of sildenafil on tissue cyclic nucleotides, platelet function, and the contractile responses of trabeculae carneae and aortic rings in vitro. 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