满足社会需要、()是生产系统的基本功能。
脑压过高,为预防脑疝最好选用()。 ["呋塞米","阿米洛利","螺内酯","乙酰唑胺","甘露醇"]
除敛肺涩肠外,还能安蛔的药物是() ["石榴皮","芡实","覆盆子","乌梅","五倍子"]
能敛肺、涩肠、止痛的药物是() ["覆盆子","赤石脂","桑螵蛸","金樱子","罂粟壳"]
环形泰勒虫的传播媒介是() ["陆地螺","钉螺","淡水螺","硬蜱","地螨"]
在市场经济的条件下,产品竞争的关键是价格的竞争,而价格竞争的基础是(),即竞争双方谁的产品成本更低廉,谁就会在竞争中占有优势。