The present invention generally relates to microRNAs such as vertebrate microRNA, for example, mammalian miRNA. Further, the bioelectrical impedance measuring apparatus of the present invention employs also the one-chip microcomputer to provide almost all the functions necessary for the measurement at a plurality of frequencies or for that using a plurality of electrodes. An additional signal or data is injected along the first line from the control system which has the effect of reducing the effect of noise from the signal or data passing along the at least second line, on the signal or data passing along the first line. The metallic pipe member is bonded to a resin case, and a signal terminal of the resin case and the pressure sensor chip are electrically connected together by wire bonding, thus forming a pressure sensor cell. And the socket connector further is incorporated with a plurality of solder balls each disposed between the encampment and the curvilinear solder portion.