x∈A∩B的否命题是( )
A.x∉A且x∉B
B.x∉A∪B
C.x∈A但x∉B
D.x∉A或x∉B
x∈A∩B为x∈A,且x∈B,
故它的否命题为x∉A或x∉B.
故选D
男性,69岁,近5年出现心悸、气短,于3个月前出现双下肢水肿,有夜间阵发性呼吸困难,体格检查发现心界向两侧扩大,心音低钝,听诊二尖瓣区有3/6级收缩期吹风样杂音。首先应考虑的诊断是()
A.心包积液
B.缺血性心肌病
C.扩张型心肌病
D.肥厚型心肌病
E.风湿性心瓣膜病
When teaching the parents of a toddler with a congenital heart defect, the nurse should explain all medical treatments and should emphasize which instruction about their child()
A. Reduce the caloric intake to decrease cardiac demand.
B. Relax discipline and limit setting to prevent crying.
C. Avoid contact with small children to reduce overstimulation.
D. Try to maintain the usual lifestyle to promote normal development.