The monitoring of physiological parameters during bathing is considered to be useful not only to prevent the accident during and after bathing, but also useful to detection of disease in its early stage. We monitored the physiological response during bathing, blood pressure, heart rate, skin blood flow and tympanic temperature. During bathing, blood pressure increased with blowing water, but it decreased without blow and heart rate increased slowly. Skin blood flow increased immediately and saturated within 2-5 minutes. Tympanic temperature increased after 3-5 minutes. These results show that these kinds of physiological parameters could be effective to monitoring during bathing. We also investigated the effective unconstrained monitoring and results show that heart rate is useful to this kind of monitoring for home use.

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In order to improve the vocal naturalness, we proposed a new control method for the electrolarynx, by which laryngectomees can control their vocal fundamental frequency (F0) through changing the respiratory pressure. This device consists of three parts: an expiration pressure sensor, a pressure-frequency converter, and a vibrator that can be attached to the neck. The control parameters of the electrolarynx, such as the airflow resistance and the transfer function from respiratory pressure to F0, were adjusted through experiments on the accuracy of F0 control and on the perceptual naturalness of the resulting voice. A well-trained normal adult was used to estimate the optimal parameter for the experiment using tones with F0 alternating in a stepwise way. The optimal gradient (F0/pressure) of the linear transform function was 25Hz/cm H₂O which gave the highest accuracy in F0 control. A laryngectomee was found to be able to control F0 after one week training with 15 minutes a day. The naturalness of an electrolarynx voice/aoi-umi/showed the highest point at the above parameter value. It was also found that the naturalness strongly depended on the training period or the difference between two subjects but not on the airflow resistance. We have developed a new electrolarynx in which an expiration pressure sensor, a pressure-vibration frequency converter, and an electromagnetic vibrator were assembled. This device was manufactured for the people who could not master esophageal speech or have just had their larynx removed.

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The dependence of the auditory evoked brain magnetic responses on the interstimulus interval (ISI), as well as on the stimulus onset asynchrony (SOA), was examined by using pure tone stimuli. Several papers have shown that the auditory evoked responses, N1 and N1m, increase as the SOA increases, which is explained by refractoriness. The peak latencies and peak amplitudes of three responses (P1m, N1m, and P2m) were measured in different blocks when the ISI was 0.5, 1.0, 1.5, and 1.95s and the SOA was 0.5, 1.0, 1.5, 2.0 and 2.5s. The peak latencies for P1m, N1m and P2m did not show any statistically significant dependence on either the ISI or the SOA. Neither ISI nor SOA had a statistically significant effect on the Plm peak amplitude. On the other hand, the N1m peak amplitude increased as the ISI increased, which is statistically significant. This means that the N1m peak amplitude dependence on the SOA includes this ISI effect because in the papers reporting this SOA dependence, an increment in SOA automatically increased the ISI. The P2m peak amplitude varied in a U-shaped manner as the SOA increased, which is statistically significant, though it did not show a statistically significant dependence on the ISI.

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Medical computed tomography has come into wide use, and it is easy to observe 3 dimensional information of living body. But, in the case of extracting tissue from CT images, shape of the tissue is complex, and other tissue information is included in the image signal, sometimes. Therefore, it is difficult to extract region of interest exactly. Occasionally, we do that manually, and also, we need someone's help who are expert for medicine. These problems are serious obstacle to make automatic extraction process. We propose an automatic extraction method which is based on the clumsy painter method, and introduce fractal dimension of tissue shape as a parameter of complexity of contour on image. We realized a reliable system with high extraction accuracy.

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As a basic study on operation of echo trigger pulses in relation to the extracorporeal shock wave lithotripter, the propagation and convergence of ultrasonic pulses in the human body are numerically investigated. It is assumed in the numerical model that ultrasonic pulses are emitted from piezoelectric transducers arranged on a spherical surface plane. Also investigated are the scattering, reflection and transmission of the pulses by solid scatterers and obstacles similar to renal calculus placed around the focal region. Numerical analysis is performed by a method similar to the FD-TD method widely used for analyzing electromagnetic fields.

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Lumin in a potent cell activating agent and a photsensitizer characterized by typical absorption peaks at 670nm and 770nm. In our preliminary results, a transplanted human cancer was dramatically cicatrized by collagen and removed by a photoimmunotherapy of small lumin administration with laser light irradiation. To treat a malignant tumor of the deep organs of the body using lumin with laser light, we developed new needle type photoimmunotherapeutic system. The system is composed of a needle to inject lumin solution and an optical fiber to guide the laser light to a cancer cell nest. To study the efficacy of the system, human lung cancer was grafted onto nude mice. After the tumor was hypertrophied, the mice were divided into four groups of three mice each; i. e. a control group, a group receiving laser irradiation only, a group receiving lumin administration only and a group receiving lumin administration with laser irradiation. Lumin of 5ng was injected and the tumor was irradiated with the laser (1.5mW, 60sec.). The treatment was performed every other day for three weeks. In the group receiving lumin administration with laser irradiation, the whole tumor was strongly cicatrized by collagen fiber from the stroma. The immunological function was investigated using the flow cytometric assay, which was analyzed by the two-color method based on immunofluorescence labeling with specific monoclonal antibodies for the sampling of 10⁴ cells harvested from mouse peripheral blood. The ratios of T and B cells in the control and laser groups were 0.25 and 0.23, respectively, and the ratio in the lumin administration group was 0.34. That in the lumin administration with laser irradiation group, on the other hand, was 0.57. Thus, it was suggested that the immune function was enhanced for the treatment of cancer by th needle type photoimmunotherapeutic system.

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