yī shēng / zǐ xì / jiǎn chá / le / bìng rén / de / dà jìng mài / què bǎo / xuè yè / liú tōng / zhèng cháng医生仔细检查了病人的大静脉,确保血液流通正常。The doctor carefully examined the patient's vena cava to ensure normal blood circulation.