[Seasonal variations in the incidence of duodenal ulcer: fact, artifact or fiction?].
D003430:Cross-Sectional Studies; D004381:Duodenal Ulcer / Q000453:epidemiology*; D005860:Germany, West; D006801:Humans; D012621:Seasons
Jahreszeitliche Häufigkeitsschwankungen bei Ulcera duodeni: Fakt, Artefakt, Fiktion?