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131.
The effects of (R)alpha-methylhistamine and N alpha-methylhistamine on intestinal transit were examined in mice. The passage of a charcoal meal in the gastrointestinal tract was dose dependently inhibited by N alpha-methylhistamine (1-20 mg/kg i.p.), but not by a selective H3 receptor agonist (R)alpha-methyl-histamine (1-50 mg/kg i.p.). The inhibitory effect of N alpha-methylhistamine (20 mg/kg) was attenuated by pretreatment with H1 receptor antagonists (mepyramine 5 mg/kg i.p. or 5 micrograms i.c.v. and triprolidine 5 mg/kg i.p.), but not by cimetidine (10 mg/kg i.p.), zolantidine (5 mg/kg i.p.), a brain-penetrating H2 receptor antagonist, or thioperamide (5 mg/kg i.p.), a selective H3 receptor antagonist. The effect of N alpha-methylhistamine was also attenuated by combined treatment with phentolamine and propranolol (5 and 15 mg/kg s.c., respectively) and by pretreatment with 6-hydroxydopamine (20 mg/kg i.p., 2 days before). N alpha-Methylhistamine markedly decreased histamine turnover in the mouse brain. These findings suggest that intestinal transit is inhibited by N alpha-methylhistamine via stimulation of central H1 but not H3 receptors and that stimulation of the sympathetic system is involved in this effect.  相似文献   
132.
In order to realize electronic devices on plastic film, new technology has been developed that enables the transfer of thin-film devices from an original substrate to another substrate by using laser irradiation. This technology was termed SUFTLA, which stands for surface-free technology by laser annealing. A polycrystalline-silicon thin film transistor (poly-Si TFT) back-plane for liquid crystal displays (LCDs) with integrated drivers was fabricated using a low-temperature process (below 425/spl deg/C) and could be successfully transferred from a glass or quartz substrate to plastic film using this technology. This technology enabled us to fabricate an all-plastic substrate TFT-LCD having a display area of 0.7 in measured diagonally and a pixel count of 428/spl times/238. In addition, the operation of the integrated drivers and the displayed image could be confirmed for the first time in the world.  相似文献   
133.
Effects of ketamine on somatosympathetic reflex discharges induced from sympathetic trunk with electrical stimulation of superficial peroneal nerve were investigated in 51 cats under anesthesia with urethane and alpha chloralose. These reflex discharges through spinal cord and medulla oblongata consist of two components, A and C reflexes, which are derived from somatic myelinated and unmyelinated afferent fiber respectively. Amplitudes of both A and C reflex potentials were depressed significantly after intravenous injection of ketamine 10 mg.kg-1. The maximum depression was observed 5 min after administration. In decerebrated cats with surgical transection at the midbrain, both A and C reflexes were also depressed after administration of the same dosages, and the maximum level of the depression was more profound than that in brain intact cats. After intrathecal injection of ketamine 1 mg.kg-1 to the lumbar spinal region, a slight depression of C reflex was found, but, dosages of 10 mg.kg-1 significantly depressed both A and C reflexes to the similar levels as those in iv injection to brain intact cats. The maximum depression was observed 30 min after administration. The depressive effects on both reflexes of intravenous ketamine 10 mg.kg-1 were not antagonized by naloxone 0.06 mg.kg-1 in brain intact cats. These results suggest that the suppressive effects of ketamine on somatosympathetic reflexes are caused by direct inhibition of medulla oblongata and spinal cord, whereas supra-midbrain regions may be activated by ketamine, and the effect of ketamine is predominant on medulla oblongata in this situation rather than on the spinal cord.  相似文献   
134.
The electronic structures of lanthunum (La) incorporated hafnium (Hf)-based oxides (HfLaO) and their silicate (HfLaSiO) films were investigated by the Near Edge X-ray Absorption Fine Structure (NEXAFS) technique. The oxygen (O) K-edge spectra, which reflected the hybridized Hf 5d state with the O 2p orbital, were found to reveal features of the unoccupied state of the metal oxides, as well as the conduction-band edge. We also found that, while La incorporation into the Hf-based oxides simply changed the features of the conduction-band structure, subsequent thermal annealing of the La-incorporated films led to a conduction-band edge shift due to an interface silicate reaction and/or local bond rearrangement depending on the La concentration and annealing temperature. The impact of La incorporation into the Hf-based high-k materials on the electronic structure is discussed by taking into account the intrinsic nature of these metal oxides.  相似文献   
135.
Polymer filters treated by plasma-assisted graft polymerization (PG), nonthermal plasma (NTP) and PG followed by NTP treatment are developed for use as multifunctional filters that can simultaneously remove odor and particulate. A NTP-treated filter can adsorb a large amount of a typical odor component, ammonia (NH3). However, the performance of the NTP-treated filter deteriorates significantly after one month whereas that of a PG followed by NTP-treated filter deteriorates only slightly. The particulate collection efficiency of a both-side PG-treated filter is higher than that of an untreated filter whereas that of the NTP-treated filter is slightly lower.  相似文献   
136.
137.
To inspect the post-accident nuclear core reactor of the TEPCO Fukushima Daiichi nuclear power plant (F1-NPP), a transportable fiber-coupled laser-induced breakdown spectroscopy (LIBS) instrument has been developed. The developed LIBS instrument was designed to analyze underwater samples in a high-radiation field by single-pulse breakdown with gas flow or double-pulse breakdown. To check the feasibility of the assembled fiber-coupled LIBS instrument for the analysis of debris material (mixture of the fuel core, fuel cladding, construction material and so on) in the F1-NPP, we investigated the influence of the radiation dose on the optical transmittance of the laser delivery fiber, compared data quality among various LIBS techniques for an underwater sample and studied the feasibility of the fiber-coupled LIBS system in an analysis of the underwater sample of the simulated debris in F1-NPP. In a feasible study conducted by using simulated debris, which was a mixture of CeO2 (surrogate of UO2), ZrO2 and Fe, we selected atomic lines suitable for the analysis of materials, and prepared calibration curves for the component elements. The feasible study has guaranteed that the developed fiber-coupled LIBS system is applicable for analyzing the debris materials in the F1-NPP.  相似文献   
138.
To gain a better understanding about the effect of growth temperature on heat resistance of Yersinia enterocolitica, we determined decimal reduction times at 60 degrees C (D60-values) for O:3; O:5,27; O:8; and O:9 strains harboring virulence plasmid coding for Yersinia outer membrane protein and experimentally virulence plasmid-deleted strains after they were grown to stationary phase at 7, 25, or 37 degrees C. Bacteria were inoculated into Trypticase soy broth and were incubated at several temperatures. D60-values of O:3; O:5,27; and O:8 strains were larger when they were grown at 37 degrees C than at 7 or 25 degrees C, despite the presence or absence of virulence plasmids. However, similar D60-values were observed in O:9 strains, despite growth at 7, 25, or 37 degrees C. The results indicate two types of Y. enterocolitica strains, growth temperature-dependent and -independent, and a Yersinia outer membrane protein that is not directly involved in growth temperature-dependent heat resistance.  相似文献   
139.
140.
LiAlO2crystals are obtained conventionally in the form of powder. In a few publications, crystal growth of rod-shaped LiAlO2 has been described, but the fiber length was very short, <4 μm. In the present study, rod-shaped β-LiAIO2 crystals 10 to 15 μm long were grown using LiOH-AI2O3NaOH as the raw material.  相似文献   
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