title: Is the more (intricate) the better?
authors.forename: Stefan
authors.initials: S
authors.lastname: Kostianev
authors.forename: Blagoi
authors.initials: B
authors.lastname: Marinov
authors.forename: Dimitar
authors.initials: D
authors.lastname: Iluchev
mesh_terms: D002245:Carbon Dioxide / Q000097:blood; D002940:Circadian Rhythm / Q000502:physiology*; D016000:Cluster Analysis; D006801:Humans; D000860:Hypoxia / Q000097:blood; D010100:Oxygen / Q000097:blood*; D010108:Oxyhemoglobins / Q000378:metabolism*; D017286:Polysomnography; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood*; D012307:Risk Factors
chemical_list: D010108:Oxyhemoglobins; D002245:Carbon Dioxide; D010100:Oxygen