A human nucleic acid, PD2, its encoded protein and antibodies immunologically specific thereto are disclosed herein. The front and back substrates and the outer frame are bonded with an adhesive to form a hermetically sealed space. Therefore, the torsion coil spring 3 is skewed in the twisted state and a round line 31c of the end portion is pressed to the guide rod 21, but a concave groove 21a is formed at the corresponding position of the guide rod 21, and the round line 31c is fitted into the concave groove 21a to stop the guide rod 21. The IFT block is an inverse Fast Fourier Transform block or an inverse Discrete Fourier Transform block. An interval is defined between the sound wave generator and the substrate.