Publications by authors named "Yamabayashi H"

New polymer gel dosimeters consisting of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol monoethyl ether monomethacrylate (TGMEMA), polyethylene glycol 400 dimethacrylate (9G), tetrakis (hydroxymethyl) phosphonium chloride as an antioxidant, and gellan gum as a gel matrix were prepared. They were optically analyzed by measuring absorbance to evaluate a dose response. The absorbance of the polymer gel dosimeters that were exposed to (60)Co γ-rays increased with increasing dose.

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Nubp1 (also known as Nbp35) and Nubp2 (also known as Cfd1) proteins are known to be responsible for regulating centrosome duplication in mouse and ribosome biogenesis in yeast. Nubp proteins contribute to diverse physiological functions. It is thought that Nubp1 and Nubp2 proteins interact with each other and regulate their functions.

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The functional residual capacity (FRC) and airway resistance (R(aw)) of the rat were measured, using a newly designed body plethysmograph (BPG), the inner environment of which was maintained at body temperature and was water-vapor saturated. The subjects were anesthetized and tracheally intubated male Wistar rats (n = 15). After measuring the FRC and R(aw), we analyzed the effects of inhaled methacholine (Mch, 0-8 mg/ml) on R(aw).

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A synchronous evaluation was performed, using a quick in vivo [2-(14)C]thymidine labeling method, of the toxico- and pharmaco-dynamics of a given dose of yttrium-90 (90Y) at a given time after injection to nude BALB/c mice loaded with 10(7) HuO9 cells. Quantitative data were 14C-microautoradiographs of the liver lobule, intestinal crypts, epiphysial growth plate, secondary ossification center containing pluripotent stem cells, perifollicular zone containing unipotent stem cells in the spleen, and plasmacytoma cells in the osteogenic sarcoma in each mouse following a 10-min labeling with 14C at 0.5, 6, and 24 h after i.

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Purpose: The effects of aging on muscle metabolism and oxygenation have not yet been elucidated. We evaluated the effects of aging on energy metabolism and oxygenation in sedentary healthy subjects by simultaneously measuring 31P-magnetic resonance spectroscopy (MRS) and near-infrared spectroscopy (NIRS).

Methods: Nine young (28.

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Nuclear magnetic resonance transverse relaxation time (T2) was previously measured in studies of lung water. The T2 decay curves for peripheral lung tissue were found to be multiexponential with two T2 components: T2 fast (T2f) and T2 slow (T2s). This behavior was explained by the compartmentalization of water, in which the protons of water are restricted and do not undergo rapid exchange between the compartments.

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Models of pulmonary edema have been used to study the nuclear magnetic resonance (NMR) characteristics of lung water. Several investigators have measured changes in the relaxation times in the permeability type of pulmonary edema, but relatively few have measured relaxation times in the hydrostatic type of pulmonary edema. In this study we determined the characteristics of NMR relaxation times T1, T2 (Hahn spin-echo decay) and water content in acute hydrostatic pulmonary edema induced by noradrenaline administration in rats.

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We investigated the relationship between nutritional status and muscle energy metabolism during exercise in 18 male patients with chronic obstructive pulmonary disease (COPD) and 15 male control subjects using 31P nuclear magnetic resonance spectroscopy (31P-MRS). The patients and control subjects were further categorized as in either a well-nourished (% ideal body weight, % IBW > or = 90) or malnourished (% IBW < 90) state. Muscle energy metabolism was evaluated by determining the ratios PCr/(PCr + Pi) (PCr, phosphocreatine; Pi, inorganic phosphate), and ATP/(PCr + Pi + ATP).

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To interpret the MRI signal intensities, the T1 and T2 values were determined in vitro for rat lungs with radiation pneumonitis, fibrosis or pneumonia, and also for muscle and fat tissues. The transverse magnetization decays mentioned above exhibited two components, a T2 fast (T2f) and a T2 slow (T2s) component. Lungs from rats with pneumonia had significantly longer T2f and T2s values than lungs from rats with radiation pneumonitis and fibrosis.

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We recently developed a method of proton magnetic resonance spectroscopy (1H-MRS) to measure the 1H-MR spectra of peripheral blood lymphocytes (PBL) using only 10(7) cells. We investigated the clinical feasibility of this method for evaluating disease activities in sarcoidosis and interstitial pneumonitis. PBL was separated from 10 ml of venous blood by differential centrifugation with Ficoll-Conray.

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It remains unknown how increased upper airway resistance (UAR) during sleep could be a function of gravity. We therefore conducted quantitative evaluation of the gravitational influence on diaphragmatic EMG activity (EMGdi) in an astronaut to estimate the effect of UAR in space. EMGdi was recorded by paired surface electrodes on the ground (control, C) and abroad a short-term space mission (space, S) for 30 consecutive h.

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A 74-year old male was referred to the Tokai University Hospital for evaluation of abnormal opacities on a chest roentgenogram. Laboratory tests demonstrated leukocytosis, elevated ESR and CRP, elevated LDH, and hypoxemia. The chest roentgenogram demonstrated several ill-defined nodular infiltrates on the bilateral upper lung fields.

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We report a 71-year-old female patient with primary alveolar hypoventilation syndrome who received diaphragm pacing (DP) and developed obstructive sleep apnea syndrome (OSAS). Application of nCPAP markedly improved her nocturnal hypoxemia. The monitored polygrams before and after the application strongly suggested that the main mechanism of OSAS was an imbalance of activity between upper airway dilator muscles and pump muscles.

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Spontaneous electrical activity of extrathoracic trachea was recorded along with force developed by tracheal smooth muscle and phrenic nerve activity in decerebrated, paralyzed, and artificially ventilated dogs with pneumothorax. The tracheal electrical activity exhibited slow oscillating potentials that were coupled with spontaneous phasic contraction of trachea. Both rhythmic changes were synchronous with central respiratory rhythm represented by phrenic burst, independent of the respirator's rhythm.

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The role of reperfusion injury in the progression to necrosis in pulmonary embolism was evaluated. To simulate this condition, we used a technique that enables occlusion and reopening of the pulmonary arterial branch supplying the right upper lobe in conscious rats. The rats were divided into five groups: the occlusion group (n = 12), in which the pulmonary artery (PA) branch was occluded without reperfusion; the reperfusion group (n = 12), in which the PA branch was reopened after a 2-h period of occlusion; and the reperfusion-SOD (n = 9), reperfusion-IM (n = 8), or reperfusion-IA-SOD (n = 6) groups, in which superoxide dismutase (SOD), indomethacin (IM), or inactivated SOD (IA-SOD), respectively, was administered during reperfusion.

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To evaluate the energy metabolism of peripheral skeletal muscle during exercise in patients with chronic respiratory impairment, the 31P-nuclear magnetic resonance (NMR) spectra of forearm muscle were investigated in nine patients and nine age-matched control subjects. We calculated the phosphocreatine (PCr) to PCr + inorganic phosphate (PI) ratio, the time constant of PCr recovery and the intracellular pH. The exercise consisted of repetitive hand grips against a 2-kg load every 3 s for 6 min (0.

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Activity of the respiratory muscles during natural defecation was studied in two anesthetized and two decerebrate dogs. In anesthetized dogs, excitation of the abdominal muscles and an increase in gastric pressure were observed during defecation. However, pleural pressure was little influenced by such increase in abdominal pressure, maintaining the same rhythmic changes as observed during spontaneous respiration.

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Abscess formation is uncommon in eosinophilic lung disease. In this paper we present a case of chronic eosinophilic pneumonia in which bronchofiberoscopy revealed scattered small abscesses in the large airways. Pathological examination revealed the presence of inflammatory cells with eosinophilic infiltration in both the bronchial mucosa and lung parenchyma.

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A 38-year-old man was admitted with persistent productive cough and right anterior chest pain. Chest X-ray showed two large masses connected with each other, one in the right lung field and the other in the anterior mediastinum. A tentative diagnosis of either lung abscess or bronchogenic carcinoma was initially made, because of elevated serum tumor markers (SLX and SCC) and persisting refractory inflammatory sings.

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Electrical activity of the tracheal smooth muscle was studied using extracellular bipolar electrodes in 37 decerebrate, paralyzed, and mechanically ventilated dogs. A spontaneous oscillatory potential that consisted of a slow sinusoidal wave of 0.57 +/- 0.

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To investigate the neural mechanism of the expiratory activity of the inspiratory muscles during a cough, EMG of the respiratory muscles were recorded in anesthetized and tracheostomized dogs. A laparoscope was used to minimize injury to the abdominal muscles for implantation of the electrodes into the costal diaphragm. During the expulsive phase of a cough, the diaphragm was active in 7 of 12 dogs and the external intercostal muscle was active in 3 of 6 dogs.

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We report a case of a 61-year-old male without any predisposing factors. His X-ray film showed multiple nodular lesions in bilateral lung fields. Open lung biopsy revealed Zygomycetes in the granuloma.

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