Background: Allergic rhinitis (AR) is a chronic disease that is becoming increasingly common worldwide and has a negative impact on school performance, work performance, and quality of life. The aim of this study was to investigate the effect of vitamin D on the symptoms of AR in children.

中文翻译：

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血清维生素D水平对儿童过敏性鼻炎症状的影响

背景：过敏性鼻炎 (AR) 是一种慢性疾病，在世界范围内变得越来越普遍，对学校表现、工作表现和生活质量产生负面影响。本研究的目的是调查维生素 D 对儿童 AR 症状的影响。