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Volume 40, Issue 1
Displaying 1-6 of 6 articles from this issue
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Yoshinori FUNAMA, Yoshio NOGUCHI, Masamichi SHIMAMURA2002 Volume 40 Issue 1 Pages 1-6
Published: March 10, 2002
Released on J-STAGE: October 14, 2011
JOURNAL FREE ACCESSIn the screening for lung cancer by helical computed tomography (CT), the detection of Type A according to Noguchi's classification is important. However, Noguchi's Type A, which shows low CT values, is difficult to detect. In particular, at low doses the detection rate further decreases because of artifact noise in the upper lung fields and in the dorsal areas of the middle lung. To reduce artifact noise, we processed the images containing artifact noise (degraded images), which were obtained by using a phantom with a CT value similar to that of Noguchi's Type A, with an adaptive Wiener filter. Moreover, clinical images diagnosed as primary lung cancer were processed with the same method for the phantom. The reduction in artifact noise in such images was assessed by signal-to-noise ratio (SNR) improvement and by visual evaluation. The detection of Noguchi's Type A with low CT value has been improved by the use of an adaptive Wiener filter.View full abstractDownload PDF (3671K) -
Keita TANAKA, Gang WANG, Kazutomo YUNOKUCHI2002 Volume 40 Issue 1 Pages 7-12
Published: March 10, 2002
Released on J-STAGE: October 14, 2011
JOURNAL FREE ACCESSWe examined EEG power spectrum theta, slow-alpha, and fast-alpha bands while the subjects were performing a working memory task. Fifteen healthy males participated. The tasks required comparing each of the current stimuli to the one that had appeared on either the verbal or spatial attributes 1-3 trials previously. A frontal midline theta rhythm increased in the power spectrum with increased memory load. Moreover, a parietal and occipioparietal slow-alpha signal decreased with the increase of working memory load. These signals were insensitive to the type of stimulus attribute being processed. On the other hand, a parietal fast-alpha signal showed a significant difference between hemispheres during the spatial version of the task. This result suggests that the spatial and verbal working memory tasks differently modulate the component of the neural circuit.View full abstractDownload PDF (1683K) -
Masaki YAMAGUCHI, Yukiko FUKUSHI, Yuji KAWABATA, Tomoya KAMEI2002 Volume 40 Issue 1 Pages 13-19
Published: March 10, 2002
Released on J-STAGE: October 14, 2011
JOURNAL FREE ACCESSWe have been focusing on the development of noninvasive methods to measure the blood glucose level by analyzing painlessly collected gingival crevicular fluid (GCF). A positive correlation may exist between blood and the GCF glucose levels because the components of GCF are mainly derived from plasma. However, its flow rate is only 2 to 3μL per hour per tooth. We fabricated a GCF-collecting device, designed to be disposable, for use in the collection and determination of the GCF. A long-term clinical evaluation was performed to determine the organic safety and the time-course changes in measurement accuracy when this GCF-collecting device was used. As a stimulative test, the gingival crevice of a guinea pig was stimulated by the device 3 times a day for 7 days. No abnormality was observed in the clinical observations or in macroscopic or organization findings. Therefore it was confirmed that the GCF-collecting device could be used safely. Next, the time-course changes of the GCF glucose levels were measured in 7 normal subjects for 2 weeks. The correlation coefficient was initially 0.90±0.11, but it was lowered to 0.77±0.13 over the two weeks. The present study demonstrated that this procedure may be used to estimate blood glucose level noninvasively.View full abstractDownload PDF (4898K) -
Tadashi INABA, Yasutomi KINOSADA, Shingo KAWASAKI, Hideaki OBATA, Masa ...2002 Volume 40 Issue 1 Pages 20-27
Published: March 10, 2002
Released on J-STAGE: October 14, 2011
JOURNAL FREE ACCESSThe cardiac contractility in human heart was investigated by analyzing the deformation of the left ventricular wall during systole, using a magnetic resonance tagging technique. The subjects were 10 normal humans, 8 patients with hypertrophic cardiomyopathy (HCM), and 7 patients with hypertensive heart disease (HHD). The circumferential strain at a short-axis section was employed as an index to evaluate cardiac contractility. The results showed that the circumferential strains in local regions of patients with HCM were significantly smaller compared with those in corresponding regions of normal humans, but the circumferential strains of patients with HHD were similar to those of normal humans in whole regions. This study may suggest that the circumferential strain could be an effective index for the quantitative evaluation of the cardiac contractility.View full abstractDownload PDF (6506K) -
Yuzuru OKAZAKI, Jun NAKAZOE, Youji ISHIYAMA2002 Volume 40 Issue 1 Pages 28-35
Published: March 10, 2002
Released on J-STAGE: October 14, 2011
JOURNAL FREE ACCESSMetal electrodes (Ag/AgCl) with paste have been used in measuring bioelectric signals. In long-term measurement, however, problems will occur, such as noise and drift caused by the movement and drying of the electrode. To solve these problems, researchers have examined capacitor-coupled electrodes without paste to measure bioelectric signals. But none has been applied in practice because they are unstable and noisy. We propose a new capacitor-coupled electrode that uses a reoxidized layer on a BaTiO3 semiconductor with the electrode (Ag) of the ferroelectric capacitor as a coupling component. This new electrode is applied to a system for measuring eyeball movement potential, and the measurement was successfully achieved without paste by use of the proposed electrodes embedded in the nose pads of eyeglasses.View full abstractDownload PDF (2833K) -
2002 Volume 40 Issue 1 Pages 38-56
Published: March 10, 2002
Released on J-STAGE: October 14, 2011
JOURNAL FREE ACCESSDownload PDF (3186K)
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