In this paper, a computer analysis of cineangiogram useful for measuring left ventricular volume is discussed. We propose an improved algorithm by which the ventricular boundary and aortic valve position are automatically detected. The proposed algorithm takes advantage of the template matching of intensity patterns and the shape matching of point sequences between consecutive fames, based on relaxation labeling method. This algorithm was applied to the single plane and biplane cineangiograms of patients with various heart diseases. The extracted left ventricles were in good agreement with manual tracings made by cardiologists. From the results obtained, the various kinds of cardiac functions, such as volume change, wall motion, pressure-volume relation and so on, can be evaluated.
It has been shown that the accuracy of pressure-volume relation obtained from the extracted ventricles is enough to analyse the pump function, contractile state and diastolic properties of the left ventricle.

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The optical biotelemetry using free-space light transmission in a closed space has many advantages over the conventional telemetry techniques using radio waves. There are some reports on the optical telemeters using direct light transmission, but few are found which use the indirect light scattered from a ceiling, a floor and walls. Since the latter technique does not require the line-of-sight transmission, it enables us to realize the non-restraint measurement of biological signals.
In order to examine the possibility of this technique, the distribution of the indirect light in a room was calculated by a computer simulation. The distribution is uniform enough to carry out the telemetry with one receiver in the room with the dimension of W4.2×L6.4×H2.7m. The minimum received power was -28.0dBm with the transmitter power of 1 watt, which was about a half of the maximum power.
To verify the possibility shown in the theoretical analysis, an optical biotelemetry system using the indirect light transmission was developed. 3 ECG's and a body temperature are multiplexed in time domain and modulated into a PIM pulse sequence. Light emitters placed on both shoulders emit the light of about 1 watt when the pulse is on. The system can be operated over 100 hours without replacing batteries.
To examine the practical usefulness of this technique in clinical application, the optical biotelemetry from a freely moving subject is carried out with the developed system. A stable data acquisition was demonstrated even from the subject in exercise.

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In this study, using the previously developed walkway system, temporal and distance factors of Cerebral Palsy (C. P.) children's gait were collected and compared with that of normal subjects, which have been collected already.
Gait analysis of C. P. children were performed in view of introducing not only general property but also individuality in each subject. Coefficient of variation and symmetricity were found not to be always useful indeces to distinguish normal gait and C. P. children's gait, whereas these two kinds of statistics have been used frequently. Only coefficient of variation of step width showed relatively clear difference between C. P. children's gait and normal gait.
One of typical characteristics of C. P. children's gait was that they cannot step their feet forward but scattering right and left. In order to formulate quantitatively the above characteristics, the meandering index and the amount of fluctuation of gait velocity in each step were calculated, and resulted to establish the above. Temporal and distance factors observed over a range of gait velocity was found to be useful indicators of C. P. children's gait. Application of gait equation resulted that C. P. children are poor in controllability of swing time and step length.

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The electric resistance of the Millipore DOPH membrane is increased in the mixed salt solution such as KCl and CaCl₂, and it oscillates rhythmically under which a current and a pressure stimulus are applied simultaneously. This paper shows electric current (I)-voltage (V) characteristics to derive the plausible mechanism of the resistance oscillation. The current and voltage responses were observed by using the current-voltage clamp circuit which was made by us. The amplitude of the current response increased in proportion to the clamped voltage till 400mV, but above its value the response oscillated. The voltage as well as the current response oscillated also under which the clamped current was kept a value above 0.15μA. These results indicated that it was difficult to describe the oscillation mechanism with a negative conductance as observed in living cell membranes. The Millipore DOPH membrane consists of many small membranes such as oil droplets, spherical micelles and multilayers formed in filter pores. The oscillations observed under clamp conditions were caused by such complex structure. From I-V characteristics, however, it seemed that the oscillation occurred in a single filter pore. Therefore, the structure of the Millipore DOPH membrane could be shown by the simplest model substituted the pore for a capillary. Using the capillary model it could be easily illustrated that the sustained oscillation was caused by the conformational change of the small membrane in one capillary.

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It is well known that it is difficult to heat deep-seated tumors by the induction method. In this paper, we proposed a new induction method which use two exciting coils, and theoretically and experimentally discussed it's feasibility in clinical use.
For theoretical and experimental analysis, we used a cylindrical model filled with the homogeneous agar solution which had almost the same electrical and thermal properties as those of human muscle.
In order to heat deep-seated tumors by the induction method, coils of various shapes were theoretically discussed.
We heated the phantom by these coils and measured temperature distributions. These results agreed well with theoretically calculated values, and showed that this method could provide the better temperature distribution than that provided by the usual method.
Applying this method to inhomogeneous model of human body, we calculated temperature distributions by the finite differential method. Those computed results showed that hot spots were able to be eliminated. This method and heated wherever we wanted by use coils of appropriate shape.
From these theoretical and experimental results, it is concluded that we can control temperature distribution in patients to a certain degree by this method, and this method can be used for clinical application.

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Auditory Evoked Fields (AEF) elicited by stimulus of pure tones were measured from the lateral head of humans using a SQUID (superconducting quantum interference device). The waveforms of the magnetic fields had two opposite peaks at -100ms and -180ms latencies, and their maximum amplitude was -700fTp-p.
Current dipoles were assumed as the sources of the AEF, and their location, direction and moment were estimated from solutions of least-squares fit. The sources were estimated in the vicinity of the auditory area of right and left hemispheres with a moment of 3-30nA·m. The dipole moment estimated at the right hemisphere was larger than the dipole momoent at the left hemisphere.

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A custom CMOS LSI for an implantable telemetry system has been developed for acquisition of biomedical informations. This implantable system consists of four parts separated from each other, that is, command receiver, missing pulse decoder, functional memory and conditioner.
They are all fabricated on one single silicon chip of 4×5mm².
The CMOS LSI's of this system are designed and implemented to get as small size and as low power consumption as possible. A specific implanted sensor is selected by a signal from the external circuit and its output signal is transmitted to the receiver by telemetry.
Another function implemented in the system is baseline adjustment of the implanted sensors by external command signals.
Using an internal pulse powered command receiver the system is capable of disconnecting itself from power source when it is not in use.

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Recently magnetocardiogram (MCG) has begun to attract doctor's considerable attention. However its medical meaning is not yet fully understood.
The purpose of this letter is to develop a method that can aid doctor to study the MCG's meaning more easily. In order to attain this, the data of MCG waves were interpolated by using the bicubic B spline function and can produce a considerably fine image clear to see. Then we constructed a movie from arranging such images in time sequence. After seeing the movie, almost all the doctors have appreciate it because they could well recognize the contents and movement of the MCG data.

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This article deals with an ultrasonic equipment, that obtains M mode echo images of peripheral vessel using electro-acoustic transducer of 20MHz resonance frequency, and automatic M mode image processing system using microcomputer.
Construction of this equipment is the same as that of echo cardiogram, but the resonant frequency of the probe is much higher than of echo cardiogram.
This equipment have a good resolution of 0.15mm and observation depth of 15mm in axial. This is suitable for observation and measurement of peripheral vessel within the shallow.
M mode image data is transferred into the main memory of the microcomputer as a digital image with 128×512 pixels through 8 bit A/D converter.
Four borders of the vessel are detected from the digital image which is previously smoothed and noise canceled by digital filter.
Ability of this equipment and system is demonstrated showing, as an example, M mode image of radial artery and detected four borders of it.

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