Search Results - (Author, Cooperation:S. Uchida)

2018-03-16

The American Society for Microbiology (ASM)

0270-7306

1098-5549

Biology

Medicine

2018-05-19

American Association for the Advancement of Science (AAAS)

2375-2548

Natural Sciences in General

2014-05-09

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

2016-04-14

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

2015-02-13

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

2011-07-23

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

1089-7550

AIP Digital Archive

Physics

We have developed a multichannel high-resolution superconducting quantum interference device magnetometer for measuring biomagnetic fields produced by small animals. We measured the magnetocardiogram produced by a rat. Topographies of the P wave, QRS wave, and T wave of the rat magnetocardiogram were obtained. We also measured the magnetoretinogram, visually evoked magnetic fields, and auditory evoked magnetic fields of the rat. The signals of the magnetoretinogram appeared at 60 ms latency and the field intensities were about 0.6 pT. It was not possible to obtain the clear visually evoked fields because those signals were hidden behind the magnetoretinogram. It was possible to obtain auditory evoked magnetic fields of the rat. The significant differences of the wave forms were observed in both sides of the right ear, which are separated by 15 mm. Our system has adequate spatial resolution for measurement of the magnetocardiogram and auditory evoked magnetic fields produced by small animals. © 1998 American Institute of Physics.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

Samples of LaBa2 Cu3 O7−y have been synthesized, which show a superconducting transition above 90 K. One of the samples shows a superconducting transition with an onset at 93 K and a zero resistivity at 92 K. These temperatures are the highest among those reported so far on this system and even higher than those in YBa2 Cu3 O7−y. The magnetic susceptibility measurement also shows that it has a superconducting transition with onset at around 93 K. To synthesize such good LaBa2 Cu3 O7−y requires two important procedures. First is sintering above 950 °C in N2 gas atmosphere and the second is annealing at 300 °C in dried O2 gas atmosphere.

Electronic Resource

1089-7550

AIP Digital Archive

Physics

The purpose of our study was to identify the current source produced by acute ischemia and infarction. We measured magnetocardiograms (MCG) and electrocardiograms (ECG) of five male rats using a high-resolution dc superconducting quantum interference device gradiometer in a magnetically shielded room after performing coronary artery occlusion. The spatial resolution of the detecting magnetic field of our system is higher than the typical system, thus permitting the measurement of magnetic fields in small animals. Distribution of the magnetic fields B(t) and distribution of |rot B(t)|, which corresponded to the distribution of the current source, were imaged by 12-channel MCGs. As a result, the distribution of current source changes in the affected area of the myocardium during the ST segment, and amplitude of the peak significantly increased after occlusion. Our system can be used to help clarify the mechanism of the ST shift related to severe heart disease. © 2000 American Institute of Physics.

Electronic Resource

1089-7550

AIP Digital Archive

Physics

The effect of the lanthanide substitution on the superconductivity in Ba2YCu3O7 and (La,Sr)2CuO4 is investigated. The substitution effect is completely different between the two Cu-oxide systems. In Ba2YCu3O7, the replacement of Y with lanthanides gives negligible change in the transition temperature, whereas a few percent of lanthanide substitution depresses Tc by about 10 K in the (La,Sr)2CuO4 system. The depression of Tc in the latter system depends on the atomic number of lanthanides. From the results of the magnetic susceptibility and the relationship between the lattice parameters and Tc , we conclude that the depression of Tc cannot be ascribed to the magnetic effect nor to the volume effect. Possible mechanisms for the depression of Tc are discussed.

Electronic Resource

1471-4159

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Guanylate cyclase (EC 4.6.1.2) of synaptic plasma membranes of rat cerebral cortex was stimulated about 6-fold by several unsaturated fatty acids (arachidonic, linolenic, linoleic, oleic, palmitoleic and myristoleic acid). Ricinoleic acid (12-hydroxyoleic acid) was much less effective. Saturated fatty acids (C10 and C14-C20) and the methylester of linoleic acid were ineffective. Stimulation by linoleic acid was influenced by the concentration of enzyme protein. At 480 μg/ml of protein 0.6 mm-linoleic acid produced maximal activation of 6-fold_ Activity stimulated by linoleic acid examined with 1.0 mm-GTP was maximal at pH 7.8-7.9 and with 2 mm-MnCl2, whereas basal activity showed broad optimal pH and Mn2+-concentration dependence. Activation of the enzyme by linoleic acid was only partially reversed by washing. Particulate guanylate cyclase of heart, small intestine, adrenal medulla, liver and lung was also activated by linoleic acid. The extents of activation (1.5-14.7-fold) by linoleic acid and the concentrations (0.2-1.0 mat) required for maximal activation depended on the tissues.

Electronic Resource

1089-7666

AIP Digital Archive

Physics

The interaction of high-intensity contrast, picosecond, 1-μm laser pulses with solid metal targets is studied with Kα emission from multilayer targets, fast ion blowoff, and other diagnostics. It is found that the characteristics of the interaction are determined by the intensity of the p-polarized component of the incoming laser field, rather than the total intensity. Consistent with resonance absorption, 20%–30% of the laser energy is deposited into suprathermal electrons that have temperatures from 2–10 keV.

Electronic Resource

1440-1681

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

1. Effect of (-)-epigallocatechin-3-O-gallate (EGCG), a condensed tannin isolated from green tea leaves, on the life span and hypertensive lesions in the stroke-prone spontaneously hypertensive rat (SHRSP) was compared with that of persimmon tannin.2. Long-term administration of either 0.5% EGCG or 0.5% persimmon tannin to SHRSP inhibited the incidence of stroke and prolonged the life span, but did not affect the blood pressure.3. These results indicate that EGCG may prevent incidence of stroke due to the radical scavenging action and inhibition of lipid peroxidation, and may result in prolonging the life span of SHRSP, as in the case of persimmon tannin.

Electronic Resource

1440-1797

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1365-2842

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The authors attempted to clarify the primary factors affecting the timing of the initial electromyographic discharges in the jaw depressor muscles (EMG onset). The changes in EMG onset in the inferior head of the lateral pterygoid (Lpt) and the anterior belly of the digastric muscles (Dig) were measured by varying duration of the open–close movement or occlusal force during the open–close–clench cycle (OCC). EMG onset tended to precede the beginning of the opening movement during OCC. The duration of opening and closing phase and the duration of occluding phase showed no significant correlation with the time-lag between EMG onset and the beginning of the opening movement (onset time).The mean EMG activity of the masseter muscle (Mm), corresponding to the occlusal force, showed a highly significant correlation with the onset time. The maximal opening velocity was highly correlated with the mean EMG activity of the jaw depressors before jaw opening. In conclusion, it was found that occlusal force is a major factor in EMG onset in the jaw depressors. It is suggested that smooth opening needs tooth contact with some degree of occlusal force.

Electronic Resource

1546-170X

Nature Archives 1869 - 2009

Biology

Medicine

[Auszug] Adiponectin (Ad) is a hormone secreted by adipocytes that regulates energy homeostasis and glucose and lipid metabolism. However, the signaling pathways that mediate the metabolic effects of Ad remain poorly identified. Here we show that phosphorylation and activation of the 5′-AMP-activated ...

Electronic Resource

0006-291X

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Physics

Electronic Resource

0006-291X

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Physics

Electronic Resource

0006-291X

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Physics

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] Formation of electron pairs is essential to superconductivity. For conventional superconductors, tunnelling spectroscopy has established that pairing is mediated by bosonic modes (phonons); a peak in the second derivative of tunnel current d2I/dV2 corresponds to ...

Electronic Resource