>YANGON, Myanmar (AP) – A powerful cyclone killed more than 350 people and destroyed thousands of homes, state-run media said Sunday. Some dissident groups worried that the military junta running Myanmar would be reluctant to ask for international help. Tropical Cyclone Nargis hit at a delicate time for the junta, less than a week ahead of a crucial referendum on a new constitution. Should the junta be seen as failing disaster victims, voters who already blame the regime for ruining the economy and squashing democracy could take out their frustrations at the ballot box.