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(2008). https://pubmed.ncbi.nlm.nih.gov/17662090/ DOI: 10.1111/j.1365-2125.2007.02990.x","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Plasma amino acids, urine NO markers and brachial FMD","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"4ec8f478-8e17-5c0c-bd89-49dfcbf3e0df","evidence_kind":"source_excerpt","locator":"Lines 918-929","start_line":918,"end_line":929,"excerpt":"### citrulline-healthy-fmd-null\nNo treatment improved FMD over baseline in the healthy-volunteer study.\nCondition category: normal\nnutrient_topic: Citrulline research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Better precursor exposure did not produce a detectable improvement in this vascular endpoint.\norganism: Human, 20 healthy volunteers\ntissue_or_cell_type: Plasma amino acids, urine NO markers and brachial FMD\nexperimental_model: Double-blind placebo-controlled crossover study\nlimitations: Small short trial; NO-related urine markers do not establish a clinically meaningful vascular benefit.\nexposure: Citrulline 0.75, 1.5 or 3 g twice daily versus arginine formulations; one-week periods\nevidence_span: {\"source_cache\": \"artifacts/citrulline-research/17662090.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"32e6ddf6d263120576f0f73c7fe3dd104904f3c0ba0a1c3f69cdca5751c4fa3b\", \"start_char\": 0, \"end_char\": 1980, \"text_sha256\": \"32e6ddf6d263120576f0f73c7fe3dd104904f3c0ba0a1c3f69cdca5751c4fa3b\"}\n[citrulline-p17662090] Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolism. 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