大脑能耐受的循环停止的"安全时限"为() ["1分钟","4~6分钟","10分钟","15分钟","1小时"]
结肠梗阻最常见的原因是() ["肠蛔虫病","肠穿孔","肠粘连","嵌顿疝","结肠肿瘤"]
关于妊娠期血液系统的变化,下列选项错误的是() ["妊娠期处于高凝状态","妊娠期出现血液稀释","孕妇红细胞沉降率减慢","妊娠期间纤溶活性降低","妊娠期血容量增加,于第32~34孕周达高峰"]
下列选项不是妊娠期循环系统的生理变化() ["心界稍向左扩大","多有第1心音分裂","整个妊娠期血压偏低","心率稍增快伴有心悸","心尖及肺动脉瓣区可闻及柔和收缩期吹风样杂音"]
鼻和鼻窦常见的恶性肿瘤是() ["恶性淋巴瘤","基底细胞癌","腺癌","鳞状细胞癌","肉瘤"]
急性心肌梗死的治疗原则。