特异性高，但与SLE活动性无关的是（）
A.抗核抗体
B.抗Sm抗体
C.抗双链DNA抗体
D.抗磷脂抗体
E.类风湿因子
参考答案：B
行车中从其他道路汇入车流前，应注意观察侧后方车辆的动态。
In order to get happiness, many people chase after reputation or money aimlessly. However, in most cases, real happiness is actually ________.
A．at ease
B．at hand
C．at length
D．at random
