下列哪一项直肠肛管疾病有恶变的倾向() ["A．内痔","B．肛裂","C．肛瘘","D．混合痔","E．直肠息肉病"] 下列哪一项适用于挂线疗法() ["A．内痔","B．肛裂","C．肛瘘","D．直肠息肉病","E．外痔"] 肛裂患者护理的要点是() ["A．止痛","B．保持排便通畅","C．抗感染","D．坐浴","E．创面敷用药物"] 肛管周围脓肿是指() ["A．内痔合并感染所形成的脓肿","B．外痔合并感染所形成的脓肿","C．直肠膀胱陷窝内的脓肿","D．肛门旁粉瘤感染所形成的脓肿","E．肛管直肠周围隙感染所形成的脓肿"] 关于肾上腺素的作用，下列描述中哪些是正确的() ["A．支气管平滑肌收缩","B．皮肤血管扩张","C．心脏兴奋性不变","D．糖原分解","E．提高胃肠道张力"] 多巴胺增加肾血流量的主要机制是()