面颈部静脉缺乏静脉瓣，临床上对哪种疾病有特殊意义

下肢静脉曲张根据哪项表现可以判断深、浅静脉交通支瓣膜功能障碍（）

简述门静脉系与腔静脉系之间的吻合部位和侧支循环

系统中雷达状态包括Unknown、Operational（or ON）、Failed（or OFF）、Detached。

Shutdown price（or point，or rule） 停业价格（或停业点、停业原则）

翻译：With Average or With Particular Average（WA or WPA）（）

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

最重要的门、腔静脉交通支是

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。