Exposure to nonmicrobial N-glycolylneuraminic acid protects farmersʼ children against airway inflammation and colitis - Frei, R; Ferstl, R; Roduit, C; Prevention of Allergy Risk factors for Sensitization in Children Related to Farming and Anthroposophic Lifestyle (PARSIFAL) study group; Protection Against Allergy Study in Rural Environments (PASTURE)/Mechanisms of Early Protective Exposures on Allergy Development (EFRAIM) study group (J Allergy Clin Immunol, 2018)