一般用股票投资收益的方差或者股票的β值来衡量一只股票或股票组合的风险。( )
参考答案:对
—What caused the party to be put off?
—__________ the invitations.
A.Tom delayed sending
B.Tom’s delaying sending
C.Tom delaying to send
D.Tom delayed to send
下列哪种说法不符合抗凝血酶活性及抗原测定()
A.待测标本不宜用肝素抗凝
B.发色底物法测AT活性,显色的深浅与AT呈正相关
C.抗原与活性同时下降为CRM-型AT缺乏症
D.抗原正常,活性下降为CRM+型AT缺乏症
E.待测标本不宜反复冻融