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J Tosa

Publications and source records attributed to J Tosa.

8 recordsLinked to original sources
PubMed1995

Visualization and quantitative analysis using normalized electromyographic linear envelopes of muscle contraction patterns during gum chewing.

Surface electromyography (EMG) has been widely used in clinical dentistry, although interpretation of the raw data is difficult owing to its low reproducibility. Linear EMG envelopes, also known as EMG profiles, which are normalized with respect to raw EMG amplitudes and stride, have been developed to analyze the time course of gait stride. Normalized EMG contraction patterns can be used for comparing individuals or recording sessions on the same individual made at different times. We made EMG profiles during unilateral gum chewing for the masticatory muscles of five asymptomatic volunteers. EMG signals were recorded from the anterior temporal (Ta), masseter (M) and anterior belly of the digastric (Da) muscles on the subject's preferred chewing side. The mandibular kinesiograph was used for tracking incisal point movement during chewing. EMGs and kinesiometric data were simultaneously recorded for 90 seconds. Ensemble averages of EMG profiles were made from 10 stable strokes after 60 seconds of initiation of chewing. Phasic characteristics of the EMG profiles were evaluated by product-moment correlation and intraclass correlation coefficients. Although the EMG profiles for Ta and M were very similar, those for Da were different from the elevator muscles.

Adult↗
PubMed1994

Differentiation of malignant glioma and metastatic brain tumor by thallium-201 single photon emission computed tomography.

The use of superdelayed thallium-201 single photon emission computed tomography (201Tl SPECT) for differentiating malignant gliomas from cerebral metastases was investigated in 23 patients (7 with meningioma, 6 with glioma, 7 with cerebral metastasis, 1 with each of neurinoma, abscess, and necrosis). 4 mCi of 201Tl was injected intravenously, and gamma camera scans were performed after 10 minutes and 4, 24, 72, and 96 hours (superdelayed scan). The mean thallium index of meningiomas was significantly higher than those of gliomas and cerebral metastases after 10 minutes, while the mean thallium indices of meningiomas and gliomas were significantly higher than those of cerebral metastases after 96 hours. The combination of early and superdelayed 201Tl SPECT may be useful in differentiating malignant gliomas from cerebral metastases.

Aged↗
PubMed1991

Intraocclusal distance between the anterior teeth in intercuspal position.

We recorded intercuspal occlusal contacts using silicone for 20 subjects with complete dentition maintaining their masseter muscle contraction levels at 10 and 30% of maximum EMG activity. A computer-aided video system was used to read the silicone image and translate the intensity of transmitted light to the thickness corresponding to the distance between opposing teeth. The intraocclusal distance was greater in the anterior than in the posterior teeth. The intraocclusal distance in the canines was intermediate between that in the incisors and posterior teeth. Although these tendencies were the same at the 10 and 30% EMG levels, an increase in the EMG level decreased all the distances.

Adult↗
PubMed1986

Quantitative histology of peritumoural low density area associated with glioma on CT; image analyzing study of peritumoural low density area after steroid-osmotherapy.

In this study, an invasive site of the tumour cells was quantitatively investigated in the low density area (LDA) on computerized tomography (CT) after steroid and osmotic drug therapy (SOT) by using a texture image analyzing computer system (TAS). Twenty six patients with gliomas (10 benign, 16 malignant) were applied in this study. According to the effect to reduce the volume of LDA, patients were classified into three groups as follows; good, poor, and failed. The reduction effect of the low density volume was not significantly different between the benign and malignant gliomas. Cells including those with a large nucleus with 6.8-9.1 microns in diameter were not observed in the control group, but they were observed in the adjacent and distant parts from the centre of the enhanced tumour element in the peritumoural LDA with 0.87-0.99 percent of all cells in both the poor and failed groups. But in the good group they were significantly rarely observed in the peritumoural LDA after SOT (p less than 0.05). Furthermore, they were significantly frequently observed in the adjacent part from the centre of the enhanced tumour element in the peritumoural LDA with 0.9 percent of all cells after SOT in the malignant gliomas in comparison with the benign gliomas (p less than 0.05). Conclusively it was suggested that the treatment of glioma with peritumoural LDA on CT must be extended to the adjacent and distant part from the centre of the enhanced tumour element in the peritumoural LDA as well as the treatment of the enhanced tumour mass on CT in the poor and failed groups.

Adolescent↗
PubMedDate not supplied

Quantitative analysis of occlusal balance in intercuspal position using the T-Scan system.

The T-Scan system was used to evaluate the distribution of time and force in occlusal balance. Sixty normal subjects demonstrated bilateral balance and an anteroposterior center of force in the first molar region. However, patients with craniomandibular disorders demonstrated marked differences from the control group. The T-Scan system was found to be clinically useful as a diagnostic screening method for occlusal stability in intercuspal position.

Bite Force↗