This paper is concerned with an investigation of a flow-absorption system, which is one of the most fundamental physiological systems. A mathematical model is developed to solve the concentration profile of absorbed solvents in a tubule. The profile depends upon the values of reaction velocity parameters, i. e., J_max and K_t. For the five different absorbed solutes, of which reaction velocity parameters are observed in a proximal tubule of a triturus kidney, digital simulation has been executed to investigate the control mechanism.
The following have been clarified :
(1) Concentration is reduced to zero at about half the length of the tubule, making the last half redundant in a steady state condition.
(2) Reaction velocity parameters have mutual compensation effect with regard to the concentration profile formulation. In other words, so long as J_max and K_t change in values in accordance with a certain linear relationship, almost equal concentration profiles can be obtained. Thus, even though the value J_max, (K_t), may be subjected to some perturbation, the concentration profile can be maintained unchanged by adjusting the K_t value, (J_max).
(3) Among J_max and K_t values of the five different solutes, linear relationship exists, providing almost equal concentration profiles. This is a very simple control algorithm 'to preserve only the common profile for different solvents.
Characterized by these merits, the flow-absorption system can be identified as an excellent control system.

抄録全体を表示

The author has developed two new types of audiometer with built-in micro-computer, and capable of automated pure-tone air-conduction threshold audiometry and speech reception-discrimination audiometry according to the test program based On the standard manual audiometric procedure established by the Japan Audiological Society.
The characteristics of the two instruments are as follows :
1. In the air-conduction threshold audiometry, pure tones of any 8 frequencies from 125 to 8 000 Hz can be optionally chosen for automated testing. Programs for subject's instruction and response exercises are stored in the equipment.
2. In the speech audiometry, the subjects respond to the audible or inaudible test speech signals recorded on a cassette tape, by pushing the terminal keys which are arranged in the order of the Japanese alphabet.
3. Accurate calculations and judgments of obtained data are performed by micro-computer built into each equipment.
4. Both can be used manually as conventional audiometers.

抄録全体を表示

In order to assess the equilibrium function of various patients quantitatively, a force plate which records sway of the center of gravity of a standing subject has been used recently in otorhinolaryngology, orthopedics, clinical neurology and other fields. From the data of a force plate, it is possible to calculate, for example, displacement, velocity and power spectrum of sway of the center of gravity. But it seems that a restriction is imposed on the information which is obtained under the condition of quiet standing.
We have tried to design and make a servo-controlled force plate that could follow arbitrary wave form input horizontally in order to get dynamic information about the equilibrium function. For the convenience of manipulation and maintenance, we adopted an electrical servomechanism which employed a /print motor as an actuator. The platform is supported by two beam type load cells and one spherical bearing and the point of application (center of pressure) of vertical force is determined.
Preliminary analysis of reactions of normal subjects to platform movements indicated that this servo-controlled force plate would provide valid information of postural performance not only in clinical application but also in physiology and physical training.

抄録全体を表示

The electromyographie silent period can be observed prior to the reaction movement to stimulus following the tonic contraction in the preraratory phase. It has been called the “premotion silent period” (p. s. p.). In order to analyze the mechanism of the premotion silent period, the relationship between frequency of the p. s. p. appearance and grade of the tonic contraction has been investigated in the present study. The following results were drawn.
1. Determination of the p. s. p. appearance has relied on subjective standard. It is more preferable that the determination is objectively judged. To confirm the R. s. p. appearance, the mean wave and the zero-crossing pulse of the raw EMG were available.
2. Two different types of the silent period were found in the reaction movement with the elbow joint extension. In one, electrical activity preceding the phasic discharge was entirely absent, and in the other it decreased or incompletely disappeared. These silent periods were named the “complete p. s. p.” and “incomplete.p. s. p.” respectively.
3. The p. s. p. appearance was observed frequently under the condition of less than 30 % to the maximum strength during the preparatory phase. It has tended, to decrease in frequency with the tonic contraction. These results are discussed in terms of the alpha-gamma linkage.

抄録全体を表示

At the outpatient clinic of Kitasato University Hospital, physicians have found the need for quick ID (identification) service of the drugs presented by their patients. As this type of service is provided by the DI (drug information) specialists of the hospital and often takes several hours the physicians usually treat the patients without knowing exact names of the drugs prescribed by their (patients') former doctors. To improve this situation, use of a simple drug identification system by means of a mini-computer (YHP 21-MX) with remote CRT terminal has been tried out. Referring to 3 DI manuals, 2 435 kinds of preparations, most of which were in the form of either tablets or capsules have been selected, and their brand names, factory names and ID information were stored respectively on the computer discs. If the ID code of a preparation is given from the CRT terminal located at the outpatient clinic, the computer system responds with the brand name and factory name of the drug within 20 seconds. If a preparation in question has no ID code, however, physicians will not receive any information under this system. From January 1, 1977 till June 30, 1977 the staffers of the DI room identified 803 preparations in reply to the request of physicians. We made the computer system imitate these DI services of this period and estimated the usefulness of it from the standpoint of the 'reliability of the answers, namely, the rate of correct identification and rejection. Of the 803 preparations, 529 were satisfactorily identified, while no information was available for 249. Due to incomplete ID information, two or more brand names were given simultaneously for 25 preparations. Although this system still has many points to be revised, these results suggest that the computer-aided DI system is of value in outpatient clinic and could save absurd labor imposed on DI staffs.

抄録全体を表示