Methods:This study was a double-blind, randomizes, placebo-controlled, flexible dose study of sildenafil citrate oral tablets taken 8 weeks.

• 方法:采用随机双盲、安慰剂平行对照、剂量可调的持续8周的临床研究,例受试者参加本研究。72结果:临床有效率西地那非组为,安慰剂组为88。89%25;