Objective To investigate the differences in serum 25-( OH) D level or not between healthy children and children with asthma,and to observe the number of attacks and the improvement of pulmonary function in the asthmatic cases after the intervention treatment with vitamin D3. Methods 100 healthy children and children with bronchial asthma aged between 3 and 10- year- old were selected respectively. The venous blood for those asthmatic children were collected in March,June,September and December,during which ...