About: http://webisa.webdatacommons.org/450959710

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Various types of cannula or trocar assemblies are provided with valves for maintaining a certain gas pressure in the cavity when the trocar or other surgical instrument is removed from the cannula.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com.au