L arginine ( L Arg), a precusor of NO, had no direct effect on sleep and W, but blocked the effect of L NNA.是什么意思_L arginine ( L Arg), a precusor of NO, had no direct effect on sleep and W, but blocked the effect of L NNA.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句