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原稿種別: 表紙
2003 年 59 巻 7 号 p.
Cover24-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 表紙
2003 年 59 巻 7 号 p.
Cover25-
発行日: 2003/07/20
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原稿種別: 目次
2003 年 59 巻 7 号 p.
Toc19-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 目次
2003 年 59 巻 7 号 p.
Toc20-
発行日: 2003/07/20
公開日: 2017/06/30
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倉西 誠
原稿種別: 本文
2003 年 59 巻 7 号 p.
I-
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内田 勝
原稿種別: 本文
2003 年 59 巻 7 号 p.
II-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
III-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
IV-VII
発行日: 2003/07/20
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
VIII-
発行日: 2003/07/20
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
IX-XII
発行日: 2003/07/20
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XIII-XIV
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XV-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XV-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XVI-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XVI-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XVII-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XVII-XVIII
発行日: 2003/07/20
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XVIII-
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XVIII-
発行日: 2003/07/20
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
XIX-XX
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室 伊三男
原稿種別: 本文
2003 年 59 巻 7 号 p.
799-803
発行日: 2003/07/20
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渡辺 典男
原稿種別: 本文
2003 年 59 巻 7 号 p.
804-810
発行日: 2003/07/20
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平田 吉春, 隅田 博臣
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2003 年 59 巻 7 号 p.
811-
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岡崎 宣夫
原稿種別: 本文
2003 年 59 巻 7 号 p.
812-813
発行日: 2003/07/20
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佐々木 康夫
原稿種別: 本文
2003 年 59 巻 7 号 p.
813-815
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阿部 一之
原稿種別: 本文
2003 年 59 巻 7 号 p.
815-817
発行日: 2003/07/20
公開日: 2017/06/30
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祐延 良治, 笹垣 三千宏, 松村 泰志
原稿種別: 本文
2003 年 59 巻 7 号 p.
817-820
発行日: 2003/07/20
公開日: 2017/06/30
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太田原 美郎
原稿種別: 本文
2003 年 59 巻 7 号 p.
821-822
発行日: 2003/07/20
公開日: 2017/06/30
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Purpose : Trans-sphenoidal-sinus approach with Hardy's endoscope is the standard technique for pituitary tumor. However, this approach has difficulty with limited operation field and requires modification according to 1) shape of nasal septum, 2) structure of the sphenoidal-sinus, and 3) tumor size. Preoperative 3D-CT may enable simulation of the approach with accurate nasal septum and sphenoidal-sinus morphology and tumor size. Methods and Materials : Preoperative 3D-CT was performed in 8 patients with pituitary tumor. Based on the 3D-CT images, 1) shape of nasal septum, 2) structure of the sphenoidal-sinus, and 3) tumor size viewed from trans-sphenoidal-sinus approach was evaluated and compared with the actual findings obtained by surgery. Results : 1) Shape of the nasal septum (no deviation, deviated to the left or right) by preoperative 3D-CT was identical to the findings by surgery. 2) Structural type (sellar, presellar, or conchal) determined by 3D-CT agreed well with the type determined by surgery. 3) Tumor size by 3D-CT was also identical with the actual size measured at the time of surgery. Conclusions : Preoperative 3D-CT enables simulation of trans-sphenoidal-sinus approach with accurate nasal septum and sphenoidal-sinus morphology and tumor size.
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三村 誠一, N. Iwata, T. Yamane, Y. Hirata, F. Tanino, S. Sugihara, T. Kino ...
原稿種別: 本文
2003 年 59 巻 7 号 p.
823-824
発行日: 2003/07/20
公開日: 2017/06/30
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Background : Intracranial MR venography is useful for the diagnosis of dural sinus thrombosis and the preoperative assessment of sinus patency encased by tumors. Recently, contrast-enhanced MR venography has been applied for suspected dural sinus occlusion in a shorter time. However, it has some disadvantage for the evaluation of hypervascularized enhancing thrombus mimicking flow in chronic sinus thrombosis. So far, we have evaluated optimal imaging technique and slice orientation and have shown that sagittal three-dimensional (3D) -phase contrast (PC) imaging is the most suitable for the non-contrast intracranial MR venography. Purpose : To assess the optimal presaturation pulse (SAT) and velocity encoding (VENC) for the non-contrast intracranial 3D-PC MR venography. Methods and Materials : Firstly, we performed phantom experiment to assess the best SAT thickness using arterial presaturation. Second, MR imaging was performed in 7 healthy volunteers to measure the dural sinus flow velocity using a 1.5 T MR. Third, 3D-PC MR venography was performed with a VENC settings at 10, 15, 20 and 30 cm/sec for healthy volunteers. All data were displayed as maximum intensity projection images and three neuroradiologists assessed the visibility of the dural sinuses and the cortical vein. Results : The mean flow velocity of the dural sinuses was 6.3 cm/sec. The thickness of the best SAT was 100mm. In the assessment of the visibility of the 3D-PC images, dural sinuses were adequately visualized at a VENC of 15 cm/sec. Conclusions : Non-contrast intracranial 3D-PC MR venography was optimized at 100mm thickness of SAT and a VENC of 15 cm/sec.
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小泉 幸司, K. Masuda, M. Komizu, Y. Ikemoto, M. Yoshimura, H. Iguchi, A. H ...
原稿種別: 本文
2003 年 59 巻 7 号 p.
825-826
発行日: 2003/07/20
公開日: 2017/06/30
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Purpose : To analyze reproducibility of ADC measurements on different MRI scanners. Methods and Materials : Diffusion-weighted imaging (DWI) of a home-made phantom (gelatine of different concentration was enclosed in case of circle pillar shape) was performed with the following protocol ; spin-echo type echo planar imaging ; TR=7000 msec, TE=minimal, matrix=128×128, FOV=220 mm, slice thickness=5mm, NEX=1, b-factor=0, 500, and 1000 sec/mm^2 on four different 1.5T MR scanners [GE Signa Horizon (two of them), GE Signa Horizon Lx, and Siemens Magnetom Symphony]. Image analysis were performed on a workstation (GE Medical Systems) or on an operators console of Symphony (for data of Symphony). We used two-point method. Regions of interest (ROIs) were set on every part of ADC map of home-made phantom and ADCs were measured. A linear approximation graphs were also made with every MRI scanner and b-factor. Results : A linear approximation was performed, formulas were y=-0.08x+2.32, r^2=0.84 (Lx), y=-0.09x+2.58, r^2=0.89 (Horizon-1) y=-0.11x+2.67, r^2=0.95 (Horizon-2), y=-0.08x+2.42, r^2=0.97 (Symphony) at b-factor of 500sec/mm^2. Y=-0.08x+2.33, r^2=0.91 (Lx), y=-0.09x+2.43, r^2=0.93 (Horizon-1), y=-0.08x+2.48, r^2=0.92 (Horizon-2), y=-0.07x+2.39, r^2=O.96 (Symphony) at b-factor of 1000sec/mm^2 Conclusions : ADC values measured at two MRI scanners (same model and older than the other scanners) are higher than other scanners on b-factor=500sec/mm^2, but at b-factor=1000sec/mm^2, a good relationship between every scanners was obtained. This result seems to depend on generation of the MRI scanners ; newly scanners have good relations b-factor 500 and 1000sec/mm^2. Pulse sequence design may be improved and optimized in newly scanners. When ADCs were used as quantitative value, a proper b-factor must be used.
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上總 中童
原稿種別: 本文
2003 年 59 巻 7 号 p.
827-829
発行日: 2003/07/20
公開日: 2017/06/30
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高羽 順子, 安部 伸和, 福田 浩
原稿種別: 本文
2003 年 59 巻 7 号 p.
831-838
発行日: 2003/07/20
公開日: 2017/06/30
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In many cases of myotonic dystrophy, high-intensity areas are seen in the cerebral white matter on T2-weighted imaging. Brain MRI was performed in 15 patients with myotonic dystrophy using diffusion tensor imaging, which is sensitive to the detailed structure of white matter, and the results were compared with those of normal controls. FA (anisotropic diffusion) values in the cerebral white matter of myotonic dystrophy patients were significantly lower than those of normal controls (p<0.01), even if the hyperintense lesion was not seen on T2-weighted imaging. Values of trace (isotropic diffusion) in myotonic dystrophy patients were significantly higher than those of normal controls (p<0.05), except in the posterior limb of the internal capsule. Diffusion tensor imaging could detect pathological change of the cerebral white matter in myotonic dystrophy patients, and may be useful for quantification and detection of subtle pathological change.
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宮崎 茂, 安部 真治, 加藤 洋, 小林 弘昌, 上原 英夫
原稿種別: 本文
2003 年 59 巻 7 号 p.
839-847
発行日: 2003/07/20
公開日: 2017/06/30
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Because interventional radiology (IVR) procedures are being performed with increasing frequency, patient X-ray exposure dose for X-ray fluoroscopic and radiographic procedures should not be ignored. In order to avoid excessive X-ray exposure, exposure dose rate limits are specified in the Japanese Industrial Standards (JIS) and by civil law at 50 mGy/min for usual fluoroscopy and 125 mGy/min for high-dose fluoroscopy. In the present study, we examined the difference in patient incident dose rate before and after using an X-ray generator that satisfied the above requirements. For incident dose to the image intensifier (I. I. ), we investigated the differences between continuous and pulsed fluoroscopy, the effects of additional filters (Ta : tantalum, Al : aluminum), and the form of the X-ray spectrum. For pulsed fluoroscopy using PMMA (polymethyl-methacrylate), the maximum patient incident dose rates of usual and high-dose fluoroscopy were 59 mGy/min and 151 mGy/min, respectively. With regard to I. I. incident dose, saturation was observed beginning at a PMMA of 20 cm, and the X-ray dose was insufficient. In terms of the difference in patient incident dose rate with Ta and Al filters, the dose rate with the Ta filter was approximately 50% lower than that with the Al filter except for the saturation area. Concerning the X-ray spectrum, it was considered that a Ta filter not only minimizes patient X-ray exposure (because Ta reduces soft X-rays more effectively than Al) but also minimizes scattered X-rays because it filters out hard X-rays, leading to improved image quality. However, the use of the filter is appropriate only when a sufficient I. I. incident dose can be ensured. Specifically, the use of the filter under saturation conditions can lead to deterioration in image quality. Therefore, IVR X-ray systems must be equipped with an appropriate filter for reducing X-ray exposure while maintaining a sufficient I. I. incident dose rate.
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左藤 智春
原稿種別: 本文
2003 年 59 巻 7 号 p.
848-856
発行日: 2003/07/20
公開日: 2017/06/30
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The MM50 is a racetrack microtron capable of taking out photon beams and electron beams with energies of up to 50 MeV. It flattens the beam by the beam-scanning method, while the microtron MM22 utilizes a flattening filter. The head-scatter factors (hereafter called S_h) , which are important for evaluating the output of the photon beam of the MM50 and MM22, were measured using a mini-phantom and build-up cap. Sh measured with the build-up cap showed the influence of contaminated electrons, whereas S_h measured with the mini-phantom showed less influence, even for 50 MV photon beams. Compared with the MM22, the MM50 showed less change in S_h according to field size and energy. The reason for this seemed to be that the MM50 has a smaller extra-focal region than other accelerators equipped with flattening filters and, therefore, can essentially be considered a point source by using the beam-scanning method without a flattening filter. This study demonstrated that photons scattered by the flattening filter used for beam flattening in typical medical accelerators mainly contribute to S_h.
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山本 桂一, 宮崎 茂, 浅野 宏, 篠原 文章, 石川 光雄, 井手 敏典, 安部 真治, 根岸 徹, 三宅 博之, 今井 宜雄, 奥秋 ...
原稿種別: 本文
2003 年 59 巻 7 号 p.
857-863
発行日: 2003/07/20
公開日: 2017/06/30
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Our X-ray systems study group measured and examined the characteristics of four transportable inverter-type X-ray equipments. X-ray tube voltage and X-ray tube current were measured with the X-ray tube voltage and the X-ray tube current measurement terminals provided with the equipment. X-ray tube voltage, irradiation time, and dose were measured with a non-invasive X-ray tube voltage-measuring device, and X-ray output was measured by fluorescence meter. The items investigated were the reproducibility and linearity of X-ray output, error of pre-set X-ray tube voltage and X-ray tube current, and X-ray tube voltage ripple percentage. The waveforms of X-ray tube voltage, the X-ray tube current, and fluorescence intensity draw were analyzed using the oscilloscope gram and a personal computer. All of the equipment had a preset error of X-ray tube voltage and X-ray tube current that met JIS standards. The X-ray tube voltage ripple percentage of each equipment conformed to the tendency to decrease when X-ray tube voltage increased. Although the X-ray output reproducibility of system A exceeded the JIS standard, the other systems were within the JIS standard. Equipment A required 40 ms for X-ray tube current to reach the target value, and there was some X-ray output loss because of a trough in X-ray tube current. Owing to the influence of the ripple in X-ray tube current, the strength of the fluorescence waveform rippled in equipments B and C. Waveform analysis could not be done by aliasing of the recording device in equipment D. The maximum X-ray tube current of transportable inverter-type X-ray equipment is as low as 10-20 mA, and the irradiation time of chest X-ray photography exceeds 0.1 sec. However, improvement of the radiophotographic technique is required for patients who cannot move their bodies or halt respiration. It is necessary to make the irradiation time of the equipments shorter for remote medical treatment.
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山田 誠一, 村瀬 研也
原稿種別: 本文
2003 年 59 巻 7 号 p.
864-871
発行日: 2003/07/20
公開日: 2017/06/30
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The image contrast of portal images obtained using computed radiography (CR) is low for radiation therapy, and their noise level is high. In order to improve the image quality of CR portal images, we investigated the relationship between the frequency components of the bone edge and noise area. We used a personal computer, conventional flatbed scanner, and public-domain software (NIH Image). To analyze the frequency components of bone edges, we generated difference images from the original and unsharp mask images of various sizes. In addition, we analyzed the frequency components of noise, after changing the cut-off frequency on the power spectrum to process a low- and high-pass filter. We found that the frequency components of bone edges and noise areas ranged from 0.18 to 0.25 cycle/mm and 1.30 cycles/mm, respectively. We conclude that this process can remove noise from homogeneous areas and preserve bone edges using multi-objective frequency processing.
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丸山 裕稔, 井手口 忠光, 大浦 弘樹, 東 敏也, 折田 信一, 天野 一弘, 東田 善治
原稿種別: 本文
2003 年 59 巻 7 号 p.
872-878
発行日: 2003/07/20
公開日: 2017/06/30
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In otorthinolaryngology, Stenvers' method is employed in radiography of the pyramid (internal acoustic meatus and semicircular canals). However, in cases of dizziness, where the prone position is difficult to achieve, we occasionally use the opposite Stenvers' method instead of the conventional one. This makes it possible to perform radiography with the patient in the supine position. Compared with the conventional Stenvers' method, the problems of this method were increases not only in the rate of magnification but also in lens dose. In this study, we evaluated these problems by employing computed tomography (CT) and a glass dosimeter with phantom as well as by clinical evaluation. The results showed no statistically significant difference between Stenvers' method and the opposite Stenvers' method in both the rate of magnification and the clinical evaluation. The increase in lens dose with the opposite Stenvers' method was not significant. We concluded that the opposite Stenvers' method was useful.
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大久保 真樹, 大越 幸和, 内藤 健一, 八木下 裕子, 蔡 篤儀
原稿種別: 本文
2003 年 59 巻 7 号 p.
879-882
発行日: 2003/07/20
公開日: 2017/06/30
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The aim of the present study was to evaluate the increase in signal intensity caused by applying the fast recovery (FR) technique to fast spin echo (FSE) images, that is, the fast recovery fast spin echo (FR-FSE) method. All images of phantoms, whose T_2 values were different, were acquired with a Signa 1.5 Tesla system (GE Medical Systems) using the three-dimensional (3D) FSE and 3D FR-FSE sequences. We assessed the increased signal intensity as follows : (signal intensity on the FR-FSE image - FSE image) /FSE image (%). Our results showed that the increased signal intensity became high when l) T_2 of the phantom was prolonged, 2) TR was shortened, and 3) echo train length (ETL) was decreased. By utilizing the results of this study, the increased signal caused by the FR technique could be estimated quantitatively when the TR, ETL, and T_2 of investigated substances were determined. For example, when TR, ETL, and T_2 were 1500 msec, 16-64, and 1500 msec, respectively, the increase in signal intensity was estimated to be approximately 70%. In addition, when T_2 was less than approximately 250 msec, signal intensity was not significantly increased by the FR pulses, that is, the FR-FSE image was the same as the FSE image. Accordingly, the FR-FSE method was confirmed to enhance the signal in substances with longer T_2, while maintaining the same contrast of the image as that obtained by the conventional FSE method. Our results are useful for evaluating the increased signal intensity caused by employing the FR technique.
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笠井 聡
原稿種別: 本文
2003 年 59 巻 7 号 p.
883-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
884-886
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
887-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
887-
発行日: 2003/07/20
公開日: 2017/06/30
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フリー
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
888-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
889-
発行日: 2003/07/20
公開日: 2017/06/30
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フリー
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
890-892
発行日: 2003/07/20
公開日: 2017/06/30
ジャーナル
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
893-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
894-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 付録等
2003 年 59 巻 7 号 p.
894-
発行日: 2003/07/20
公開日: 2017/06/30
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原稿種別: 表紙
2003 年 59 巻 7 号 p.
Cover26-
発行日: 2003/07/20
公開日: 2017/06/30
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