心脏呈梨形,心尖部可听到舒张期隆隆样杂音,其诊断为()
A.病毒性心肌炎
B.风湿性心肌炎
C.二尖瓣狭窄
D.二尖瓣关闭不全
E.房间隔缺损
参考答案:C
— I'm sorry to trouble you.
— _________. [ ]
A. It's a good idea.
B. It's very kind of you.
C. Thank you.
D. It's ok.
交换值越大,说明两个基因之间的连锁强度越(),两个连锁的非等位基因之间发生交换的孢母细胞数就越()。