align='center' title='nullable'>&nbsp;&radic;&nbsp;</td>
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 <td class='detail' align='right'>null</td>
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    <td class='relatedTable detail' title="drug_exposure.visit_detail_id refs visit_detail.visit_detail_id via fpk_drug_visit_detail"><a href='visit_detail.html'>visit_detail</a><span class='relatedKey'>.visit_deta