<prompt> True about myasthenia gravisAssociated with thymomoa in 34 of casesIncremental response seen with repetitive electric stimuliSkeletal muscle function improve after restEdrophonium test negative  <response>: The weakness increase during repeated use and may improve following sleep or rest.only 10 of cases are associated with thymomas 65 with hyperplasia of thymus. Edrophonium test is positive. In electrodiagnostic testing MG patients show a rapid reduction of 10-15 in the amplitude of evoked response. Ref Harrison20th edition pg 2445 