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topical membership is not evidence of a direct dietary effect.\nplain_language: This membrane protein brings free B1 into cells.\norganism: Homo sapiens\ntissue_or_cell_type: HeLa cells\nexperimental_model: Human placental cDNA expressed in HeLa cells; radiotracer uptake.\nlimitations: Expression-system affinity is not a blood sufficiency threshold.\ntransport_direction: Extracellular medium to cell interior.\nevidence_spans: [{\"source_document\": \"artifacts/thiamine_transport_sources/dutta-1999-slc19a2-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 1275}]\nevidence_locator: Abstract\nevidence-scope: HeLa cells\n[dutta-1999-slc19a2] Cloning of the human thiamine transporter, a member of the folate transporter family (1999). https://pubmed.ncbi.nlm.nih.gov/10542220/ DOI: 10.1074/jbc.274.45.31925","model_system":"Human placental cDNA expressed in HeLa cells; radiotracer uptake.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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