腹腔穿刺液中有大量中性粒细胞,革兰阴性杆菌。常见于()
A.原发性腹膜炎
B.胃、十二指肠穿孔
C.阑尾炎穿孔
D.肝脾破裂
E.出血坏死性胰腺炎
参考答案:C
As we the big crowd, I got from my family.
A.joined; separated
B.joined in; separated
C.joined; lost
D.joined in; missed
(2011)均质杆AB长为ι,重为W,受到如图所示的约束,绳索ED处于铅垂位置,A、B两处为光滑接触,杆的倾角为α,又CD=ι/4,则A、B两处对杆作用的约束力大小关系为:()
A.FNA=FNB=0
B.B.FNA=FNB≠0
C.FNA≤FNB
D.FNA≥FNB