第1题: [填空题]The Mayas are believed as the first people to figure out______. 参考答案:the use of zero with other numerals in counting 答案解析:在倒数第二段提到"In mathematics,they could count up to the millions.They were the first people to figure out
第18题: [单项选择]不属于硝酸甘油的药理作用机制的是() A. 降低室壁肌张力 B. 降低心肌耗氧量 C. 扩张心外膜血管 D. 降低左心室舒张末压 E. 降低交感神经活性 参考答案:E 答案解析:硝酸甘油可以直接松弛血管平滑肌,特别是小血管平滑肌,使全身血管扩张,外周阻力减少,静脉回流减少,减轻心脏前后负荷,降低心肌耗氧量、解除心肌缺氧。用于心绞痛急性发作,也用于急性左心衰竭。