霍乱弧菌外毒素有A、B两个亚单位,其中A亚单位分为A1和A2,毒素的活性部分是()。 ["A1亚单位","A2亚单位","B亚单位","A亚单位","A亚单位和B亚单位"]
老年性白斑哪项是正确的() ["A.常见于暴露部位 ","B.常伴瘙痒 ","C.可自行消退 ","D.日晒后数目增多 ","E.为米粒大圆形白点,略凹陷"]
关于手后前位体位描述正确的是()。 ["受检者仰卧于摄影床旁,肘部弯曲或不曲肘","受检者坐于摄影床旁,肘部弯曲或不曲肘","被检测手掌平放于床面上,手指略分开","第三掌骨头放于检测器中心","源-像距离(SID.为120cm"]
现金流量三要素不包括()。 ["A.现金流量的大小 ","B.现金流量的方向 ","C.现金流量的作用点 ","D.现金流量的性质"]
肺栓塞的影像学表现是() ["肺透亮度降低","肺外带以胸膜为基底,尖向肺门的楔形密影","增强扫描主动脉内充盈缺损","增强扫描实变区内血管样强化,即“血管造影征”","以上都不是"]
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