Nobuyuki Kawai

Learn More
A novel technique was developed for injecting a time-varying conductance into a neuron, to allow quantitative measurement of the processing of synaptic inputs. In current-clamp recording mode, the membrane potential was sampled continuously and used to calculate and update the level of injected current within 60 microseconds, using a real-time computer, so(More)
PURPOSE To investigate factors related to the development of internal mammary arteries (IMAs) as feeding arteries of hepatocellular carcinomas (HCCs). MATERIALS AND METHODS In 30 patients with HCC located in ventral hepatic areas directly beneath the diaphragm, bilateral internal mammary arteriography was performed to explore involvement of the IMA with(More)
Glioblastoma multiforme (GBM) is characterized by tissue hypoxia associated with resistance to radiotherapy and chemotherapy. To clarify the biological link between hypoxia and tumour-induced neovascularization and tumour aggressiveness, we analysed detailed volumetric and spatial information of viable hypoxic tissue assessed by 18F-fluoromisonidazole(More)
We studied the expression of bcl-2 oncoprotein in the gerbil hippocampus after transient ischemia. Immunostaining using monoclonal antibody raised against bcl-2 oncoprotein revealed intense immunoreactivity in the CA1 area following 2 min of ischemia, which induced tolerance to subsequent ischemia and prevented delayed neuronal death (DND). Following(More)
In order to measure unitary properties of receptor channels at the postsynaptic site, the noise within the decay phases of inhibitory postsynaptic currents (IPSCs) and of N-methyl-D-aspartate (NMDA)-dependent excitatory postsynaptic currents (EPSCs) in rat hippocampal neurons was studied by nonstationary fluctuation analysis. Least squares scaling of the(More)
Although it is generally accepted that humans cannot perceive sounds in the frequency range above 20 kHz, the question of whether the existence of such "inaudible" high-frequency components may affect the acoustic perception of audible sounds remains unanswered. In this study, we used noninvasive physiological measurements of brain responses to provide(More)
In guinea-pig myocardial mitochondria preparation, lowering the Ca2+ concentration or pH level in the perfusate rapidly elevated the fura-2 Ca2+ signal ([Ca2+]m). Pretreatment with 10(-4) M L-Arg inhibited the rapid [Ca2+]m influx, whereas administration of 10(-4) M L-NAME did not, suggesting some association between nitric oxide (NO*) synthase (NOS)(More)
A cornerstone of Einstein's special relativity is Lorentz invariance-the postulate that all observers measure exactly the same speed of light in vacuum, independent of photon-energy. While special relativity assumes that there is no fundamental length-scale associated with such invariance, there is a fundamental scale (the Planck scale, l(Planck)(More)
In a Simon task, participants show better performance when the irrelevant stimulus location corresponds with the response location than when it does not, and this effect is typically greater for older adults than for younger adults. To study the effect of cognitive ageing in the Simon task, we compared young and old adults using two versions of the Simon(More)
Background: We studied whether or not the expressions of MMP-2 and MMP-9 were correlated with the proliferative potential or recurrence of intracranial meningiomas. Methods: The expressions of MMP-2 and MMP-9 of 56 meningioma tissues were examined and scored by immunohistochemistry (IHC). Expressions of the mRNA of each MMP were also examined by reverse(More)