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Asthma research has been greatly facilitated by the introduction of fibreoptic bronchoscopy which is now a commonly used technique in the field of respiratory disease research , allowing collection of biopsy specimens , bronchial brushing samples , and bronchoalveolar lavage fluid enabling use of disease - derived cells and tissues in some of these models .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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