Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering最新文献

Roles of reactive oxygen species in monocyte activation induced by photochemical reactions during photodynamic therapy. 光动力治疗过程中活性氧在光化学反应诱导单核细胞活化中的作用。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138932

Miho Takahashi, Tomokazu Nagao, Yoshiharu Imazeki, Kazuki Matsuzaki, Haruyuki Minamitani

{"title":"Roles of reactive oxygen species in monocyte activation induced by photochemical reactions during photodynamic therapy.","authors":"Miho Takahashi, Tomokazu Nagao, Yoshiharu Imazeki, Kazuki Matsuzaki, Haruyuki Minamitani","doi":"10.1163/156855701321138932","DOIUrl":"https://doi.org/10.1163/156855701321138932","url":null,"abstract":"This study attempts to investigate the mechanism of the vascular shut down (VSD) effect during photodynamic therapy (PDT) with zinc coproporphyrin III tetrasodium salt as a photosensitizer. PDT is a treatment based on photochemical reactions and the resultant cytotoxic reactive oxygen species (ROS). Platelet thrombus formation leading to stasis observed in vivo during PDT is called the VSD effect. Leukocytes play an important role in the VSD effect in vivo, but the mechanism how activated monocytes generate ROS is not known in detail. To evaluate ROS generation by activated monocytes is especially important to clarify leukocyte-endothelium interactions in the VSD mechanism. The dichlorofluorescein fluorescence intensity of monocytes with four types of free radical scavenger was investigated by confocal laser scanning microscopy. The fluorescence intensity of monocytes that had been incubated with superoxide dismutase and incubated and added with L-histidine was decreased by about 20 and 30%, respectively. The result affirms the predominant role of singlet oxygen and superoxide anion radicals in monocyte activation in the VSD effect during PDT.","PeriodicalId":77139,"journal":{"name":"Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering","volume":"11 4","pages":"279-94"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/156855701321138932","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22374471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18

A comparison of abdominal ECG and Doppler ultrasound for fetal heart rate detection. 腹部心电图与多普勒超声检测胎儿心率的比较。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138950

Muhammad I Ibrahimy, M A Mohd Ali, Edmond Zahedi, Shinji Tsuruoka

引用次数: 4

Influence of cool-down exercise on autonomic control of heart rate during recovery from dynamic exercise. 动态运动后恢复过程中，冷却运动对心率自主控制的影响。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138914

Tatsuhisa Takahashi, Akiyoshi Okada, Junichiro Hayano, Toshiyo Tamura

{"title":"Influence of cool-down exercise on autonomic control of heart rate during recovery from dynamic exercise.","authors":"Tatsuhisa Takahashi, Akiyoshi Okada, Junichiro Hayano, Toshiyo Tamura","doi":"10.1163/156855701321138914","DOIUrl":"https://doi.org/10.1163/156855701321138914","url":null,"abstract":"The recovery of post-exercise heart rate (HR) is enhanced by a procedure of cooling down; however, the mechanism of this facilitated reduction is unknown. To determine whether more cardiac vagal reactivation is associated with a decrease in HR following cool-down exercise, we examined high-frequency R-R interval variability (HF, 0.15-0.40 Hz), an index of cardiac vagal tone, in six young healthy male subjects with a comparison between sitting rest after 6 minutes of cool-down cycling at 20% peak oxygen uptake (VO2peak) and sitting complete rest, following 5 min of upright cycle exercise at 70% VO2peak. During the last minute of exercise, there was no difference in HR between the two exercise tests before performing or not performing cool-down exercise (mean +/- SE, 148.7 +/- 6.9 versus 149.7 +/- 7.0 beats/min, respectively, by a Wilcoxon signed-ranks test). After exercise, a similar initial rapid decrease in HR and subsequent decline was observed during the first 6 min of recovery, regardless of cool-down exercise. However, the resting HR average following cool-down exercise was significantly lower than the corresponding HR without cool-down exercise (92.1 +/- 3.0 versus 100.8 +/- 3.6 beats/min, P < 0.05). The corresponding HF amplitude was slightly, but significantly greater with than without cool-down exercise (10.6 +/- 2.2 versus 9.0 +/- 1.9, P < 0.05). Thus the increase in HF amplitude corresponded to a decrease in resting HR following cool-down exercise, as compared to complete rest without cool-down exercise. Therefore, we conclude that after moderate exercise, the decrease in resting HR following cool-down exercise is associated with an increase in cardiac vagal tone.","PeriodicalId":77139,"journal":{"name":"Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering","volume":"11 4","pages":"249-59"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/156855701321138914","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22374469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 28

Development of an EMG recording device from stimulation electrodes for functional electrical stimulation. 功能电刺激用刺激电极肌电图记录装置的研制。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138969

Yoshihiro Muraoka

引用次数: 78

Development of a portable bruxism monitoring and analysis device equipped with a microcomputer and its practical application. 一种便携式微机磨牙监测分析装置的研制及实际应用。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138941

Ryuji Sakagami, Takeshi Horii, Shuichi Ino, Kazunari Matoba, Hiroshi Kato, Masamitsu Kawanami

{"title":"Development of a portable bruxism monitoring and analysis device equipped with a microcomputer and its practical application.","authors":"Ryuji Sakagami, Takeshi Horii, Shuichi Ino, Kazunari Matoba, Hiroshi Kato, Masamitsu Kawanami","doi":"10.1163/156855701321138941","DOIUrl":"https://doi.org/10.1163/156855701321138941","url":null,"abstract":"The purposes of this study were to develop and verify the a portable nocturnal bruxism monitoring and analysis device equipped with a microcomputer, and to clinically apply the device to know the actual conditions of bruxism patients. EEPROM was installed in the device for the data recording, and after the data collection, the recorded data was entered into a personal computer via serial port. After confirming the accuracy of the device, a total of 30 subjects were enrolled in this study to monitor their bruxism activities for 3 nights. Bruxism self-aware group consisted of 14 subjects, 7 males and 7 females, and unaware group consisted of 16 patients, 8 males and 8 females. Most of the subjects reported that the new device was easy to handle. The average bruxism time per hour and the average bruxism lasting time were 223.8 +/- 112.0 and 3.9 +/- 2.9 s in the self-aware group, and 49.3 +/- 38.3 and 0.8 +/- 0.7 s in the unaware group, respectively. The bruxism self-aware group showed statistically longer average bruxism time per hour and the average bruxism lasting time. It was confirmed that the new bruxism monitoring and analysis device is practical for clinical application to monitor and analyze the electromyographic activities.","PeriodicalId":77139,"journal":{"name":"Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering","volume":"11 4","pages":"295-306"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/156855701321138941","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22374472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

The high zero-flow pressure phenomenon in coronary circulation: a simulation study. 冠状动脉循环高零流压现象的模拟研究。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138978

Tahseen Ejaz, Tadashi Takemae, Yukio Kosugi, Minoru Hongo

引用次数: 4

A study on the rehabilitation of cognitive function and short-term memory in patients with Alzheimer's disease using transcutaneous electrical nerve stimulation. 经皮神经电刺激对阿尔茨海默病患者认知功能和短期记忆康复的研究

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138905

Yi Guo, Xuemin Shi, Hisashi Uchiyama, Akihiro Hasegawa, Yaeko Nakagawa, Masaharu Tanaka, Ichiro Fukumoto

{"title":"A study on the rehabilitation of cognitive function and short-term memory in patients with Alzheimer's disease using transcutaneous electrical nerve stimulation.","authors":"Yi Guo, Xuemin Shi, Hisashi Uchiyama, Akihiro Hasegawa, Yaeko Nakagawa, Masaharu Tanaka, Ichiro Fukumoto","doi":"10.1163/156855701321138905","DOIUrl":"https://doi.org/10.1163/156855701321138905","url":null,"abstract":"In some previous studies, transcutaneous electrical nerve stimulation (TENS) to the back was shown to improve non-verbal short-term and long-term memory as well as verbal fluency in patients in the early stage of Alzheimer's disease (AD). Moreover, the patients' physical, social and affective functions were also improved. In this study, the effects of TENS applied to the face were studied in patients with mild and severe AD. Fourteen patients with probable AD were used as subjects. To evaluate the effects of treatment, the subjects underwent two kinds of neuropsychological tests as well as a pupillary light reflex test. The pupillary light reflex test was chosen because it has been proven to show poorer results in cases of senile dementia. These three tests were carried out before the treatment, immediately after the treatment and 6 months after the treatment. Improvements were seen in subjects in the TENS groups and the effects of treatment were more significant in mild AD patients than in severe AD patients. However, the improvements were not maintained 6 months after the treatment. The possible mechanisms underlying the beneficial effects of TENS in AD patients are discussed in this paper.","PeriodicalId":77139,"journal":{"name":"Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering","volume":"11 4","pages":"237-47"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/156855701321138905","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22374468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 28

Adaptive EEG spike detection: determination of threshold values based on conditional probability. 自适应脑电图尖峰检测:基于条件概率的阈值确定。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2002-01-01 DOI: 10.1163/156855701321138923

Takenao Sugi, Masatoshi Nakamura, Akio Ikeda, Hiroshi Shibasaki

{"title":"Adaptive EEG spike detection: determination of threshold values based on conditional probability.","authors":"Takenao Sugi, Masatoshi Nakamura, Akio Ikeda, Hiroshi Shibasaki","doi":"10.1163/156855701321138923","DOIUrl":"https://doi.org/10.1163/156855701321138923","url":null,"abstract":"Determination of the threshold value for automatic EEG spike detection was investigated adopting conditional probability. An adaptive spike detection method was constructed and evaluated. A discriminant function for detecting spikes was obtained by conditional probability calculated from the EEG spike data. The relationship among false-negatives, false-positives and threshold values for the discriminant function was investigated. An adaptive detection algorithm was developed by combining different threshold values. False-negative and false-positive rates for spike detection depended on the threshold values. The adaptive spike detection algorithm achieved a high detection rate and accuracy. The advantage of the proposed method is to construct an adaptive detection algorithm by combining the threshold values according to the purpose of spike detection. Since the threshold can be easily changed in the proposed method, it is practically effective for clinical use.","PeriodicalId":77139,"journal":{"name":"Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering","volume":"11 4","pages":"261-77"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/156855701321138923","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22374470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

Mechanism of burn injury during magnetic resonance imaging (MRI)--simple loops can induce heat injury. 磁共振成像(MRI)烧伤机制——简单环路可诱发热损伤。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2001-01-01 DOI: 10.1163/156855701316922298

T. Nakamura, K. Fukuda, K. Hayakawa, I. Aoki, K. Matsumoto, T. Sekine, H. Ueda, Y. Shimizu

{"title":"Mechanism of burn injury during magnetic resonance imaging (MRI)--simple loops can induce heat injury.","authors":"T. Nakamura, K. Fukuda, K. Hayakawa, I. Aoki, K. Matsumoto, T. Sekine, H. Ueda, Y. Shimizu","doi":"10.1163/156855701316922298","DOIUrl":"https://doi.org/10.1163/156855701316922298","url":null,"abstract":"To determine the mechanism of burn injury associated with magnetic resonance imaging (MRI), the induced current in the loops of a conductive lead was measured. Seven types of loops with effective areas within the range from 100 to 12 000 cm2 were made and then each loop was placed in the bore of a whole-body MR system at 0.5 T and MRI was carried out. During radio frequency (RF) irradiation, an induced voltage was observed in loops that were placed with their axes parallel to the linearly polarized transmitting RF field. The voltage had a sincfunction characteristic and was within the range 55-235 V at the RF pulse sequence for usual MR imaging. When the axis was vertical, negligible current was observed. A resistor inserted into the circuit of a 30 x 40 cm loop sparked and burned out. Simple loops of conductive material may result in the induction of a large and potentially hazardous voltage in the imaging system. Self-resonance of such a loop may add greatly to hazards by increasing the effective coupling to the RF transmitter. Also, impedance matching of the inserted resistor with the impedance of the loop increases the dissipated power at the resistor.","PeriodicalId":77139,"journal":{"name":"Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering","volume":"2 1","pages":"117-29"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76239540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 40

A multi-element carotid tonometry sensor for non-invasive measurement of pulse wave velocity. 一种用于无创测量脉搏波速度的多元件颈动脉血压计传感器。

Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering Pub Date : 2001-01-01 DOI: 10.1163/156855701750383187

K. Narimatsu, S. Takatani, K. Ohmori

{"title":"A multi-element carotid tonometry sensor for non-invasive measurement of pulse wave velocity.","authors":"K. Narimatsu, S. Takatani, K. Ohmori","doi":"10.1163/156855701750383187","DOIUrl":"https://doi.org/10.1163/156855701750383187","url":null,"abstract":"A new pulse wave velocity (PWV) measurement system has been developed using a novel multi-element tonometry carotid sensor combined with a heart sound sensor. In this system, PWV is derived from the time lag between the second heart sound (S2) obtained from the heart sound sensor and the dicrotic notch in the carotid pulse waveform, and the physical distance between the heart and the neck. We assessed the accuracy of the system in an animal model. The study was divided into two groups: in Group I the tonometric sensor was directly applied to the exposed artery, while in Group II the sensor was applied over the skin and subcutaneous tissues covering the artery. To examine the fidelity of the dicrotic notch, the ejection time with the tonometry sensor was compared with that obtained from the intra-arterial catheter measurement. The correlation coefficients between them were 0.99 in both groups. The bias error (defined as the mean of the differences between the tonometry and the catheter measurements) +/-2SD was 0.13+/-1.45 ms in Group I and 0.16+/-1.64 ms in Group II. These results confirmed that the arterial wall, subcutaneous tissue and skin did not affect the accuracy of the dicrotic notch fidelity. The reproducibility of the system was assessed in 18 human subjects. The 2SD of intraobserver and interobserver reproducibility of the S2-carotid PWV measurement were 0.54 and 0.38 m/s, respectively, demonstrating high reproducibility of the measurement. From a clinical point of view, the S2-carotid PWV was compared with the aortic PWV. The bias error +/-2SD between the two measurements was -0.14+/-3.24 m/s with the correlation coefficient being 0.73. Although the S2-carotid PWV may not replace the aortic PWV directly, we believe that the S2-carotid PWV with the new system may become a new clinical parameter for early detection of cardiovascular disorders such as cerebrovascular diseases.","PeriodicalId":77139,"journal":{"name":"Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering","volume":"14 1","pages":"45-58"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85654468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15