在探究温度对鼠妇生活影响的实验中,实验组和对照组都应该保持相同的条件是 [ ]
A.光、温度、湿度等
B.鼠妇数量、光、温度等
C.温度、湿度、鼠妇的数量等
D.空气、湿度、光等
B
女,27岁,已婚,停经3个月,不规则 * * 流血10天,近日有恶心、呕吐,宫底高度平脐,未闻及胎心。有助于诊断的检查是
A.妇科检查
B.X线腹部平片
C.多普勒检测胎心
D.B超检查
E.血HCG定量测定
________foreign friends from different countries visit the Great Wall every year. [ ]
A. Thousands of
B. Over eight thousands of
C. Thousand of