著者

阿部 善右衛門 田中 邦雄 堀田 正生

出版者

公益社団法人 計測自動制御学会

雑誌

計測自動制御学会論文集 (ISSN:04534654)

巻号頁・発行日

vol.10, no.3, pp.290-297, 1974-06-30 (Released:2009-03-27)

参考文献数

29

被引用文献数

1

---

The possibilities for the measurements of the blood flow and water contents in the human body by NMR techniques have been analyzed during the last four years. A new technique for this purpose is proposed as one of the new approaches.This paper will deal with the following four topics connected with our past studies for noninvasive testing of biological materials.(1) Proposal of magnetic focusing techniques and generation of the focusing field.(2) Deterioration of the signal level originating frcm the loose coupling between the measuring target and the detector, and minimum limit for measurements of the stationary body fluid utilizing steady NMR.(3) Improvement on the blood flowmeter utilizing pulse NMR.(4) Measurement of the stationary body fluid utilizing pulse NMR.For non-invasive measurements of the nuclear magnetic substances distributed in the human body, a new approach is proposed by utilizing the magnetic focusing technique on the measuring target. And several methods for generating this magnetic focus are discussed theoretically. Moreover, the degree of inevitable deterioration of the signal from the focus induced by a loose coupling between the target in the body and the detector on its surface is calculated theoretically.Theoretical estimations of a new blood flowmeter are shown by taking advantages of the tag effect by radio frequency pulse on the blood flow.For this improvement of the blood flowmeter, the techniques are explained to estimate the pseudo-signal intensity originating from the neighbouring tissues around the blood vessel. A method similar to blood flowmetry can also be applicable to detect the stationary body fluids with some modifications.And some simple assumptions of the minimum limit of detectability are summarized from the view point of bio-medical applications.In conclusion, the authors are able to explain a few considerations and theoretical prospects on these applications of NMR.

著者

田中 邦雄 佐野 文男 阿部 善右衛門

出版者

一般社団法人 日本生体医工学会

雑誌

医用電子と生体工学 (ISSN:00213292)

巻号頁・発行日

vol.12, no.2, pp.81-89, 1974-04-30 (Released:2011-03-09)

参考文献数

25

被引用文献数

1

---

Several papers on the applications of the nuclear magnetic resonance (NMR) technique-for the biological measurements have been published since the first proposal of the NMR blood flowmeter by Bowman. However, the problems arising inherently from the non-invasive measurements of the specified area in the body were not discussed in these papers. The authors proposed previously the magnetic focusing technique as one of the new approaches and discussed some problems related to this technique.In this paper, some basic problems of the applications of NMR for the non-invasive measurements are discussed and the fundamental properties affecting the measuring sensitivity attained by the magnetic focusing technique is analyzed. The problems treated and the obtained results are as follows : 1) The relations among parameters such as relaxation times and radio frequency magnetic field which influence the measuring sensitivity are experimentally analyzed.2) The distributions of RF magnetic field inside or outside the transmitter coil are theoretically calculated. Approximate values of relaxation time of 1-2 sec. and 0.1-1 sec. are experimentally obtained respectively with the various body fluids and tissues of the dog and the human. Philosophy of choosing the appropriate parameters are discussed based on these results by taking the saturation factor in Bloch's equation and the measuring sensitivity into account.3) Application for the tumor detection is discussed and the differences of 20% and 200% in relaxation time between normal and cancer cases are experimentally obtained respectively with the tissues from the stomach and the breast. Further, it has been found that the relation between hematocrit of blood and its relaxation time was linear.4) The deterioration of signal output by body tissues is examined by a model experiment. According to this experiment, it is shown that the deterioration of S/N ratio was equal to approximately 30%, at f = 60 MHz.5) From above results, in the case of applying our proposed magnetic focusing technique, the resolution or the minimally detectable volume of water in the typical organs by S/N of unity at resonance frequency of 60 MHz should be about 0.3 ml.

著者

今西 二郎 渡邊 聡子 栗山 洋子 細野 八郎 田中 邦雄 矢野 忠 細川 豊史

出版者

社団法人日本東洋医学会

雑誌

日本東洋醫學雜誌 (ISSN:02874857)

巻号頁・発行日

vol.53, no.6, pp.669-674, 2002-11-20

参考文献数

4

被引用文献数

9 8

---

医学生の講義前後における東洋医学に関する意識を検討するため,京都府立医科大学の学生に自己記入式アンケートを配布した.医師に漢方を処方してもらったことのある学生は,18%,薬局で買った漢方薬をのんだことがあるのは53%,鍼灸治療を受けたことがあるのは,わずか13%であった。84%の学生が漢方医学に関心をもっており,漢方医学は勉強する価値があると思っている学生は82%,現代医療において漢方は必要であると考えている学生は76%,また将来漢方を自分の診療に取り入れようと思っている学生は54%であった.これらの数値は,講義後,それぞれ92%,85%,87%,62%に増加していた.

著者

田中 邦雄

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.61, no.1, pp.21-30, 2023-03-10 (Released:2023-08-11)

参考文献数

7

---

Already 50 years have past since the principle of MRI has been proposed. MRI has become the necessary clinical diagnostic tool such as X-CT. MRI techniques have been still in further progress. In this manuscript, the historical review of NMR and MRI were introduced, and the fundamental principle of NMR phenomena such as the principle of magnetic resonance, relaxation process and NMR information were introduced to understand MRI techniques. Following these introduction, fundamental MR imaging techniques such as 2-D Fourier Transform in relation to MR imaging, parameters of image construction, the role of gradient field, contrast enhanced images and fast MR imaging techniques were introduced.

著者

田中 邦雄 寺平 宏

出版者

信州大学環境科学研究会

雑誌

環境科学年報

巻号頁・発行日

vol.5, pp.44-54, 1983-03-31

著者

田中 邦雄 清水 哲也 佐野 文男 阿部 善右衛門

出版者

一般社団法人 日本生体医工学会

雑誌

医用電子と生体工学 (ISSN:00213292)

巻号頁・発行日

vol.14, no.1, pp.25-32, 1976-02-29 (Released:2011-03-09)

参考文献数

19

---

Since R. Damadian suggested the detectability of tumors by nuclear magnetic resonance (NMR), the authors have focused their attention on the facts such as the quantities related to the kinds of water and tissues. And at least qualitative information could be non-invasively obtained.In this paper, in order to clarify the applicabilities of our proposed magnetic focusing method for non-invasive tumor detection, the nuclear magnetic relaxation time (T1) of transplanted malignant tumor (AH-66) in rat, excised normal and cancerous tissues in man were measured in vitro experiment.The resultant findings are summarized as followings.1) Transplanted malignant tumor in rat showed (30-120) % longer value of T1 than that of the respective normal tissues.2) In 14 cases of the uterus, breast and stomach in man, the T1 of cancerous tissues increased (10-150) % than that of their normal portions.3) When mixed tissue was studied, T1 changed as the ratio of tumor to normal tissue changed.4) The longer the time elapsed, the greater the T1 value exhibited by normal and the smaller the T1 measured for cancerous tissue. When both normal and cancerous tissues coexist, T1 decrement of the tissue is small.