Masaharu Ohnishi

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OBJECTIVE Both the selective endothelin (ET) ETA receptor and mixed ETA/ETB receptor antagonists improve haemodynamics in patients and experimental models with congestive heart failure (CHF) and reduce the mortality in CHF rats. However, it remains unclear which of these antagonists is superior in the treatment of CHF. In addition, there is little(More)
BACKGROUND--Endothelin (ET)-1 is generated from big ET-1 by endothelin-converting enzyme (ECE). Plasma big ET-1 and ET-1 levels are strongly related to survival in patents with congestive heart failure (CHF). Because selective enzymatic processing of ET-1 formation appears to be an important therapeutic target for CHF, we investigated the acute effects of a(More)
Near infrared (NIR) spectroscopy, a non-invasive optical method for monitoring hemodynamics, was applied to record evoked auditory response of the human brain. Our newly developed system detected the amount of oxygenated and deoxygenated hemoglobin in the area of the local brain located beneath the probes. In the study, we used magnetoencephalography (MEG)(More)
The intensity of Galactic cosmic rays is nearly isotropic because of the influence of magnetic fields in the Milky Way. Here, we present two-dimensional high-precision anisotropy measurement for energies from a few to several hundred teraelectronvolts (TeV), using the large data sample of the Tibet Air Shower Arrays. Besides revealing finer details of the(More)
Aims To evaluate whether plasma endothelin-1 (ET-1) is extracted or produced through the heart in patients with acute myocardial infarction (AMI), and the relationship between transcardiac extraction of plasma ET-1 and left ventricular (LV) remodelling. Methods and results We measured the plasma level of ET-1 in the aortic root (Ao) and coronary sinus (CS)(More)
We will report the observations of TeV gamma ray flares from Markarian 501 using Telescope Array Prototype. The observation were carried out continuously from the end of March to the end of July in 1997. The energy spectrum, and the time variation of the gamma ray intensities are shown. The intensity has been changed by the order of magnitude in this period(More)
Since 1996, a hybrid experiment consisting of the emulsion chamber and burst detector array and the Tibet-II air-shower array has been operated at Yangbajing (4300 m above sea level, 606 g/cm 2) in Tibet. This experiment can detect air-shower cores, called as burst events, accompanied by air showers in excess of about 100 TeV. We observed about 4300 burst(More)
The inhibitory effects of calcium antagonists on high-potassium or glutamate (Glu) enhanced intracellular calcium ion ([Ca2+]i) levels were studied in cultured cerebellar granule cells. Dosages between 0.5 and 10 microM of flunarizine, nicardipine, SM6586 and SM12565 reduced the rise in [Ca2+]i induced by 50 mM KCl in a dose-dependent manner, although(More)
The purpose of this study was to elucidate the relationship between large tubules and dentin caries by using human deciduous incisors that showed various levels of attrition but no macroscopical lesions resulting from caries. The teeth were cut longitudinally in the mesio-distal direction and the exposed surfaces observed with a high-resolution field(More)