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He became chief of the Health Policy Research and Development Unit at  Massachusetts General Hospital  in 1991 and director of the Institute for Health Policy for the Massachusetts General Hospital  and Partners HealthCare  System in 1988 .
 None
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
 Entity Pairs:   
Answer:
 NA: Massachusetts General Hospital, and Partners HealthCare