Prime Minister Menachem Begin intervened Monday in the hunger strike by hundreds of Israeli doctors. The prime minister, turning to the crisis for the first time, summoned Finance Minister Yoram Aridor and Health Minister Eliezer Shostak, who have been waging a personal battle over the doctors' wages. A delegation of fasting doctors also attended the meeting in Mr. Begin's office. The week-long hunger strike is affecting hospitals throughout the country.