A method of extracting neural stem cells from a living subject, comprising the steps of introducing magnetic nanoparticles into the subject, targeting the neural stem cells with the magnetic nanoparticles to form magnetic nanoparticle-targeted cells, isolating the magnetic nanoparticle-targeted cells, extracting the magnetic nanoparticles-targeted cells from the subject. The detecting an abnormal BP condition can include detecting various forms of hypertension or hypotension. for one hour under a pressure of 30 kgfcm2, an elongation percentage of the interlayer dielectric film in a planar direction is 0. The power supply regulator is coupled to regulate the reflected voltage across the primary winding, thereby regulating the output voltage across secondary winding.