HOUSE PANEL DEALS CARTER'S TAX PLAN TWO MORE SETBACKS
HR Ways and Means Com rejects proposal in Carter tax pkg that would raise $2.8 billion in additional revenue by tightening up on income tax deductions for med expenses and casualty losses; adopts proposal by Reprs Barber B Conable Jr and Joseph L Fisher that would allow persons using short form tax return to take deductions for charitable contributions, for estimated revenue loss of $2 billion; adopts proposal by Reprs Dan Rostenkowski and Martha Keys that would raise $40 million in revenue by tightening rules on deductions for medicines and discontinue deduction for med ins costs; rejects Adm proposals that would disallow deductions for employee contibutions to state disability ins funds (M)