The differences between daytime and nighttime heart rate variability may usefully predict the apnea-hypopnea index in patients with obstructive sleep apnea-V18I6 The differences between daytime and nighttime heart rate variability may usefully predict the apnea-hypopnea index in patients with obstructive sleep apnea-V18I6 Download Prevalence, incidence, and health care utilization of patients with narcolepsy: a population-representative study-V18I6 Assessment of pleural pressure during sleep in Marfan syndrome-V18I6