The 6MWD was measured at baseline and then annually for 5 yrs in 294 patients with COPD and its annual rate of decline was determined.是什么意思_The 6MWD was measured at baseline and then annually for 5 yrs in 294 patients with COPD and its annual rate of decline was determined.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句