instruction:
Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.
question:
kurt julius isselbacher (september 12, 1925 – july 18, 2019) was a german-born american physician and gastroenterologist.
answer:
kurt julius isselbacher


question:
mariner 10 was a robotic nasa space probe.
answer:
mariner 10


question:
mario balbuena gonzález (april 16, 1959 – may 7, 2017), better known under the ring name gran apache and el apache, was a mexican "luchador", or professional wrestler and trainer.
answer:

gran apache