[名词解释] 支护强度

中枢神经系统内脑脊液产生速度为（） ["0.1～0.2ml\/min","0.3～0.5ml\/min","0.4～0.6ml\/min","0.5～0.7ml\/nun","0.6～0.8ml\/mi"] 顶板压力 支护密度 工作阻力 使用魔绳时要沿割丝螺纹方向缠绕，Dg25的管子需缠（）圈 ["6-9","8-12","15-18","20-25"] 支护强度