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			          What is COPD? Symptoms and Risk Factors - COPD Foundation
			           
 What is COPD? Learn more about COPD, COPD symptoms and risk factors and progressive lung diseases such as emphysema, chronic bronchitis and asthma. http://www.copdfoundation.org/What-is-COPD/Understanding-COPD/What-is-COPD.aspx
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			          Information on COPD - COPDGene
			           
 Chronic obstructive pulmonary disease (COPD) is a lung disease that makes it difficult to breathe. COPD affects many aspects of a person's health. COPD is a preventable and treatable disease. Its pulmonary component is characterized by airflow limitation that is not fully reversible even with the use of bronchodilator medication. http://www.copdgene.org/information-copd
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			          American Thoracic Society - What Is Chronic Obstructive Pulmonary Disease (COPD)?
			           
 Chronic obstructive lung disease (COPD) describes a group of lung conditions (diseases) that make it difficult to empty the air out of the lungs. http://www.thoracic.org/copd-guidelines/for-patients/what-is-chronic-obstructive-pulmonary-disease-copd.php
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			          Chronic Obstructive Pulmonary Disease - Wikipedia, the Free Encyclopedia
			           
 Chronic obstructive pulmonary disease (COPD), also known as chronic obstructive lung disease (COLD), and chronic obstructive airway disease (COAD), among others, is a type of obstructive lung disease characterized by chronically poor airflow. https://en.wikipedia.org/wiki/Chronic_obstructive_pulmonary_disease
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			          What is COPD? Life Expectancy, Treatment, Symptoms - Healthline
			           
 COPD kills over 120,000 Americans annually-the equivalent of one death every four minutes. Early prevention and treatment can be key to avoiding serious problems. http://www.healthline.com/health/copd
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			          COPD (Chronic Obstructive Pulmonary Disease) - WebMD
			           
 What is COPD? Chronic obstructive pulmonary disease?Chronic obstructive pulmonary disease (COPD) is a group of long - term (chronic) lung diseases that makes it hard to breathe. http://www.webmd.com/lung/copd/tc/chronic-obstructive-pulmonary-disease-copd-overview
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			          About COPD Symptoms, Diagnosis, and Exacerbations - COPD
			           
 Learn about COPD symptoms, diagnosis, and exacerbations with tips, facts, and a deeper look at the stages of COPD. Get support today for your COPD management. http://www.copd.com/about-copd
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			          CDC: Chronic Obstructive Pulmonary Disease (COPD)
			           
 Chronic Obstructive Pulmonary Disease, or COPD, refers to a group of diseases that cause airflow blockage and breathing-related problems. It includes emphysema, chronic bronchitis, and in some cases asthma. http://www.cdc.gov/copd/index.html
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			          COPD - American Lung Association
			           
 Chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis and emphysema, is a chronic lung disease that makes it hard to breathe. http://www.lung.org/lung-health-and-diseases/lung-disease-lookup/copd/
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			          COPD - Mayo Clinic
			           
 Chronic obstructive pulmonary disease (COPD) - Comprehensive overview covers symptoms, treatment of this lung disease. http://www.mayoclinic.org/diseases-conditions/copd/basics/definition/con-20032017
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			          What Is COPD? - NHLBI, NIH
			           
 COPD, or chronic obstructive pulmonary (PULL-mun-ary) disease, is a progressive disease that makes it hard to breathe. "Progressive" means the disease gets worse over time. http://www.nhlbi.nih.gov/health/health-topics/topics/copd
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			          COPD Foundation - Take Action Today. Breathe Better Tomorrow
			           
 COPD Foundation provides COPD patients and families with information on COPD, treatment resources, support programs and an advocacy center. http://www.copdfoundation.org