Pancreaticoduodenalis v . mesenterica and a . gastrolinealis join together and then enter the right liver ; v . gastrica anterior v . oesophagea join together and then enter the left liver v . abdominalis enter the liver by the ortho - axis of liver the characteristic of histology about the heart and blood vessels : cardiac muscle cells are not linked by the structure of intercalated discs ; the endothelium of blood vessels is simple columnar epithelium 3 .静脉系统:后腔静脉与后主静脉同时存在,肾门静脉系统与后腔静脉之间没有交通支,输卵管静脉汇入肾门静脉,肝门静脉分三处入肝:胰十二指肠静脉、肠系膜静脉和胃脾静脉三者汇合后进入右肝,胃前静脉和食管静脉汇合后进入左肝背面,腹静脉从肝脏腹面正中线入肝。