[P wave and respiratory function in normal, silicotic and emphysematous subjects].
D004562:Electrocardiography; D006801:Humans; D011656:Pulmonary Emphysema; D012119:Respiration; D012129:Respiratory Function Tests; D012829:Silicosis
ELECTROCARDIOGRAPHY; PULMONARY EMPHYSEMA; RESPIRATORY FUNCTION TESTS; SILICOSIS