Warning: XSLTProcessor::transformToXml() [xsltprocessor.transformtoxml]: I/O warning : failed to load external entity "file:////srv/scielo/www/bases/xml/rccb/v55/2221-2450-rccb-55-8.xml" in /srv-new/scielo/www/htdocs/class.XSLTransformerPHP5.php on line 36 NATURALEZA Y MEDICINA TRADICIONAL, PANORAMA HISTÓRICO Y ESTADO ACTUAL