1.Diagnostic criteria of COPD: 1.History: History of long-term chronic cough, more than two years, lasting more than three months per year. 2. Symptoms: High incidence in autumn and winter every year, especially after cold, coughing, coughing and wheezing, increased sputum or yellow pus sputum, coughing and shortness of breath can be regarded as acute exacerbation. 3.Signs: at the onset of the disease, there are croup or sputum sounds, and the chest may be over clear on percussion. 4, laboratory tests: pulmonary function tests for incomplete reversible airflow restriction is a necessary condition for the diagnosis of COPD. (Pulmonary function tests are the gold standard for the diagnosis of COPD: incomplete reversible airflow limitation can be determined if FEV1/expected value < 80% and FEV1/FVC < 70% after inhalation of bronchodilator). There is often a clear history of triggers or exposure, such as inhalation of cold air, exposure to pollen, paint, eating fish, shrimp, milk, etc. 2. Signs: Diffuse croup and prolonged expiratory phase can be seen in both lungs during exacerbation and may disappear during remission. Some patients with severe asthma can present silent chest even during the exacerbation period. 3.It can be relieved by itself or after treatment with bronchodilators and hormones. 4.Except other diseases that cause recurrent attacks of cough, sputum and wheezing such as slow branch, bronchial expansion, etc. 5, test: positive bronchial excitation test or exercise test; positive bronchial diastolic test: FEV1 increase of 15% or more, or FEV1 increase >200ml; PEF daily variability or diurnal fluctuation rate ≥20%. With conditions 1~4 or 4, 5, the diagnosis is established. Bronchial asthma COPD Age: children or adolescents, onset of disease after middle age Onset: rapid onset of symptoms with great fluctuation, slow progression and gradual aggravation, nocturnal and early morning symptoms are obvious IV. Causes: allergic substances, allergic rhinitis, smoking, exposure to harmful gas particles, infection, airflow restriction reversible, reversible, incompletely reversible, airway excitation test positive, generally negative (generally not used during exacerbation, wheezing) Airway diastolic test Positive Generally negative PEF diurnal variability ≥20% Clinically, because of the long duration of the disease, there may be cases of both, which are not easy to identify, and medication should be adjusted according to the response to treatment.