AMHTS developed since 10 years ago, has spread throughout the world. Even in Japan, about 40 centers of AMHTS are already functioning. AMHTS based on some special characteristics, such as operation under the idea of systems-engineering and the performance with the distinguished medical engineering technology, in which many items of tests for many persons can be finished within a short time, may be considered as an expanded health care system. The AMHTS centers are specially designed through selection of tests with their methods, consideration of the flow of examinees during the test course, and constructional features of the building.
Automated testing machines and automatic data acquisition system with computers are used. Additionally, automated diagnostic system of ECG and automated history-taking machines are also applied. Data stored in the computer are utilized as the fundamental records of health care of the individuals. The purposes of AMHTS include estimation of normalcy, early detection of disorders and diseases and health promotion according to the results of automated health check-up.
The subjects of AMHTS, in most cases, are middle-aged or old persons, but a few exceptional centers are established exclusively for women or children. Today, there are more than 300 centers functioning in U. S. A. and over 5, 000, 000 persons are accepted for tests. Reduction of the medicalexpenses and correction of imbalance in the requirement and supply of doctors should be accomplished by the application of AMHTS, which is considered as a highlighted method in the health organization maintenance or in the regional medical programs.
There are some differences between the U. S. A. and Japanese AMHTS. While the former, centers are larger in capacity and publicly managed, the latter are rather small and privately managed. The sets of AMHTS tests are almost similar in Japan and the U. S. X-ray examination of upper G-I tract is applied specially to Japanese because of the racial characteristics of the diseases. Recently, a few studies of the evaluation of AMHTS have been reported and significant responses to detecting of heart diseases, cancer and hypertensive diseases through AMHTS are arising. AMHTS will have a function of primary care among health care systems and be considered to play a roll of interface between the fields of clinical medicine and public health.

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The etiology of systemic lupus erythematosus (SLE) still remains unknown and the disease entity named SLE is not definitely but empirically constructed by the combination of the signs and symptoms (SS), and laboratory findings which are frequently observed in typical SLE and SLE-like diseases. Using the mathematical clustering technique, internal structure of SLE has been studied as to whether it can be divided into smaller groups. The Ward's method was adopted because the preliminary clustering experiments using SLE and progressive systemic sclerosis patients revealed : that the Ward's method was most preferable to treat them among seven hierarchical cluster analyses included in CLUSTAN I program written by Wishart. Each SLE case was represented in the form of multi-dimensional vector shown by existence or non-existence of 57 SS. The temporal relation of SS was not taken into consideration. The results were as follows : 1. When the original SLE group (54 cases) was divided into two subgroups, one (A) contained 30 cases, and the other (B), 24 cases. 2. Incidences of palmar erythema, general edema, psychosis, arthralgia, hypercholesteremia, hypoalbuminemia, proteinuria, hematuria and cellular casts in urine in Group B were considerably higher than those in Group A (statistically significant at the 5 % level). Relation of clustering method to the results of classification and clinical significance of the mathematically derived subgroups have not been fully discussed.

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In computer analysis of chest X-ray pictures, a large memory size and long processing time are usually necessary because of the sequential processing of the large amount of information contained in a picture. An approach which allows drastic data reduction is therefore pursued in order to develop practical systems for wide use. The contours of heart and thorax silhouettes must be intrinsically simple from the viewpoint of anatomy. However, the automated determination of the contours is not necessarily simple, because chest X-ray pictures have multi-gray levels and irrelevant silhouettes, or noises, overlap onto the contours.
Giving analytical bases to the developmental works on the automatic determination of the cardiothoracic ratios by the present author and his collaborators, discussed in this paper are :
1) a simplified cross-sectional model of the chest by introducing the concept of virtual thorax, followed by the definition of four characteristic points which are located on a density curve derived from a line scanning at right angle to the median line.
The basic concept, which is shown in analogy to the communication model, is that these points carry the information on the contours even if they might be disturbed by the noises.
2) description of the contours by Fourier series, which leads to the definition of the normalized complication measure R for the contours.
The measure R is defined as the ratio of the effective picture height to the interval of sampling points by which the contours can be approximated within specified errors. The results of statistical studies on R's with 19 random samples of chest X-ray pictures are presented.
3) the theoretical background of the algorithms for correcting errors in a data series of the characteristic points.
Two parameters, κ and η, are introduced. Also presented are the results of statistical studies on them. The criteria for error detection and correction are essentially derived from these parameters.

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A system analysis of the resting problem of workers of AMHTS center has been studied.
Large-scale AMHTS centers follow the tandem queue service model. Examination services of this system must not be broken off all at the same time because of medical restrictions. The. shift system is, therefore, proposed as one of the countermeasures that gives resting time to, the workers of every station one after the other with a relevant break time from the waiting room.
As a result of analysis, it has been found that the resting time at each station becomes shorter than the break time by the sum of the service time at that station and the waiting time at the preceding station.
A design equation is given, and this is going to be apply at the Gifu Prefectural AMHTS Center.

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A method for calculating the amount of both right to left and left to right shunts through the experimental ventricular septal defect using, an indicator dilution technique has been proposed.
A simple model of a circulating system is considered in which two partial tracts arranged in parallel, one of them a shunting tract, so that transit times through it would be shorter than those through another tract, i. e., the transit time distribution (the frequency function of transit times) through the total circulating system is made up of an early developed component and a later one. The earlier curve originates in the shunting tract and if the transit time distribution through the total circulating system is obtained, the fraction of the flow through the shunting tract can be estimated from the fractional area of the earlier component.
This concept was applied to a system of pulmonary circulation with experimental right to left shunt in dogs produced by excising a core of tissue from the ventricular septum.
Indicator dilution curves were recorded at the inlet and the outlet of the system with shunt by a relatively rapid injection of O. 5 nil of indocyanine green into the entrance of the right atrium. Direct method for measuring the indicator dilution curves were applied in order to avoid, deterioration of the curves. The inlet indicator dilution curve was monitored, introducing a fibroptic light guide with a small photodiode located at the tip of the light guide through the free wall into the right ventricle. The blood in the brachiocephalic artery which represents that in the left ventricle was transilluminated and the concentration of indicator in blood was monitored with the fibroptic light guide and a photodiode put externally on the arterial wall.
The transit time distribution through the circulating system with shunt was obtained by a numerical deconvolution of a pair of these simultaneously recorded indicator dilution curves.
In order to minimize cumulative error in successive values for calculated transit time distribution, it is desirable to obtain the value for the inlet indicator dilution curve during its first time interval as large as possible. For this purpose two procedures were carried out; first, the time interval for choosing values of the dilution curves was selected as large as possible, and second, an indicator was injected rapidly into the blood as close as possible to the monitoring site in the right ventricle.
Calculated transit time distributions through the circulating system from the right ventricle to the left ventricle with right to left shunt were, as predicted, made up of an early developed component and later one. The fraction of the flow through the right to left shunting tract could successfully be estimated from the fractional area of the earlier component.

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