iOS TableView如何刷新指定的cell或section

NSIndexSet *indexSet=[[NSIndexSet alloc]initWithIndex:indexPath.row];
[tableview reloadSections:indexSet withRowAnimation:UITableViewRowAnimationAutomatic];

NSIndexPath *indexPath=[NSIndexPath indexPathForRow:3 inSection:0];
[tableView reloadRowsAtIndexPaths:[NSArray arrayWithObjects:indexPath,nil] withRowAnimation:UITableViewRowAnimationNone];