LifePak is supported by two double-blind, placebo-controlled clinical studies, a 140-subject parallel design study and a 46-subject crossover study.是什么意思_LifePak is supported by two double-blind, placebo-controlled clinical studies, a 140-subject parallel design study and a 46-subject crossover study.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句