[Epidemiology and etiology of esophageal cancer in North China: a preliminary report].
D000328:Adult; D000367:Age Factors; D000368:Aged; D000818:Animals; D002645:Chickens; D002681:China; D004938:Esophageal Neoplasms / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality / Q000662:veterinary; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D008875:Middle Aged; D011201:Poultry Diseases / Q000453:epidemiology; D012737:Sex Factors