除下列哪种疾病外,血清RF可表现为阳性
A.亚急性细菌性心内膜炎
B.SLE
C.强直性脊柱炎
D.RA
E.慢性肺结核
参考答案:C
____ he grows up can he understand your intentions.
A.Unless
B.Once
C.Only when
D.Ever since
撤柱后不能自行冒落的顶板,应在密集支柱外0.5m处,向放顶区重新凿岩爆破,强制崩落。