Enteric coated stable oral pharmaceutical composition of acid unstable drug. The Peltier element a heat-emitting plate for emitting heat by the current provided thereto, and a heat-absorbing plate for absorbing a heat. The present invention further provides the identification of arjunic acid 1 and its derivatives as anticancer agent useful in the treatment of various types of cancer in humans. A measurement output unit outputs the clearance changed distance detected by the changed distance detection unit at the time of contact determination of the contact determination unit as a measurement result of the clearance between the reading element and the recording medium.