关于肝素的性质,下列哪项是错误的()。
A.是一种含有硫酸基团的粘多糖
B.存在于血管肥大细胞和嗜碱性粒细胞的颗粒中
C.可阻止血小板聚集
D.可促进凝血活酶及凝血酶形成
参考答案:D
23.—How did you find the lecture tonight?
—It ____ me. I doubt if I will come for his lecture next time.
A.encouraged
B.disappointed
C.reflected
D.Satisfied
采用拟合法加工非圆曲线零件轮廓时,拟合线段的各连接点称为()
A.基点
B.节点
C.交点
D.切点