Table schema:
CREATE TABLE table_name_6 (prothrombin_time VARCHAR, partial_thromboplastin_time VARCHAR, condition VARCHAR)

Question: Which Prothrombin time that has a Partial thromboplastin time of unaffected, and a Condition of thrombocytopenia?
SQL: SELECT prothrombin_time FROM table_name_6 WHERE partial_thromboplastin_time = "unaffected" AND condition = "thrombocytopenia"