Prospective Study of Bacteriology of COPS Acute Exacerbation---Emphasis on Patient Outcome, Drug Sensivity and Strain Variation of Pseudomonas aeruginosa and Changes of Bacteriology with Combination Therapy = 慢性阻塞性肺疾病患急性惡化細菌學之追蹤研究---著重於病患預後、抗生素敏感性，綠膿桿菌品系變化與吸入合併式療法對呼吸道細菌之影響