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zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"469d3f90cc5be3f1c0ef247d099fa70d81aa953b8a6b33334abc38d34f346654\", \"start_char\": 0, \"end_char\": 3999, \"text_sha256\": \"469d3f90cc5be3f1c0ef247d099fa70d81aa953b8a6b33334abc38d34f346654\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Double-blind placebo-controlled crossover studies of nitrate and calcium antagonist coadministration in healthy men and men with hypertension","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Sildenafil 25 milligrams three times daily with stepwise intravenous and sublingual glyceryl trinitrate, and a single 100 milligram dose with amlodipine","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"The design that establishes the contraindication, and the amlodipine arm is the control that shows it is specific to the shared pathway rather than additive antihypertensive effect.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Sildenafil research collection; topical membership is not evidence of a direct clinical effect, and the drug is recorded separately from its N-desmethyl metabolite and its target enzyme from the homologous retinal PDE6.","comparator":null,"unit":null,"notes":"","entity":{"slug":"sildenafil","display_name":"Sildenafil","entity_type_key":"drug"}},{"dimension":"organism","value_text":"Human","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A blood pressure drug working by another route simply adds; only the ones sharing this pathway multiply.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[sil-p10078539] Sildenafil citrate and blood-pressure-lowering drugs: results of drug interaction studies with an organic nitrate and a calcium antagonist. 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