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211.
There have been few reports on the effects of the brain-gut peptide motilin on the central nervous system (CNS). We administered motilin intracerebroventricularly to mice and investigated the effect of motilin on anxiety using an elevated plus-maze. Motilin produced a significant decrease in anxiety with an inverted U-shaped dose response. To determine whether the anxiolytic effect of motilin was mediated via motilin receptors in the brain, the effect of GM-109, a novel motilin receptor antagonist, was investigated. GM-109 showed a significant and dose-dependent antagonism on the motilin-induced anxiolytic effect. GM-109 administered alone had no effect on anxiety. These results suggest that motilin receptors are present in the brain and may have a role in anxiety and emotion.  相似文献   
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213.
P-Selectin, an adhesion molecule expressed on the surfaces of activated platelets and the vascular endothelium, mediates platelet binding to monocytes and neutrophils. Monocytes and neutrophils produce superoxide anion by activated platelets through p-selectin. Aprotinin, a serine protease inhibitor, inhibits plasmin to activate platelets during cardiopulmonary bypass (CPB). A total of 25 patients were studied to clarify the effects of aprotinin on p-selectin expression during CPB. Nine patients were not given aprotinin (control group), and 16 were given aprotinin of 2 million U in the priming solution (aprotinin group). The platelet count and soluble p-selectin in the plasma, p-selectin on the surface membranes of platelets, and leukocyte-platelet conjugate levels were measured during and after CPB. The platelet count was maintained well in the aprotinin group. The increases of soluble p-selectin in the plasma, platelet surface p-selectin, and leukocyte-platelet conjugates were less in the aprotinin group than in the control group (p < 0.05). In conclusion, aprotinin in patients undergoing CPB may reduce the early inflammatory reactions induced by p-selectin.  相似文献   
214.
We reported on the usefulness of endosonography (EUS) in the diagnosis of the depth of invasion of gallbladder carcinoma. We performed EUS on 69 patients with gallbladder carcinoma: the degree of tumor extension in 17 was m (tumor invading the mucosa), in 5 pm (tumor invading the muscular layer), in 21 ss (tumor invading the subserosa), 14 in se (tumor invading the serosa), and 12 si (tumor extending to adjacent organs). The detection rate of tumors with EUS was 91.3% (63 of 69). All 6 (100%) patients with pedunculated lesions (Ip type) were correctly diagnosed with EUS. Eighteen of 21 patients (85.7%) with broad-based elevated tumors (Is type), and 5 of 7 (71.4%) with flat-elevated lesions (IIa type) were also diagnosed correctly. EUS is a useful modality for the diagnosis of gallbladder carcinoma. In particular, EUS diagnosis of the depth of invasion is reliable in Ip-type lesions. It is recommended that patients with Ip-type lesions undergo laparoscopic cholecystectomy, but in patients with Is-or IIa-type lesions conventional cholecystectomy with lymph node resection should be performed.  相似文献   
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216.
Crystal growth of TiAl alloys   总被引:2,自引:0,他引:2  
The growth of TiAl alloys over a range of Al concentrations has been considered for ingots processed by the floating zone technique. For Al-rich alloys, single crystals of γ-TiAl cannot be grown for compositions below Ti-54 at% Al since a banded microstructure forms due to the limitations imposed by the L + → γ peritectic reaction. However, near stoichemetric TiAl crystals can be grown by the traveling solvent method when using a TiAl---Co flux, although optimum processing conditions have not yet been realized. For Ti-rich alloys, evidence of a growth morphology consisting of β-phase dendrites embedded within a continuous matrix of the peritectic -phase is found for ingots processed up to 200 mm h−1. The final lamellar orientation of the ingot is then determined by the orientation of the peritectic -phase and not by that of the leading β dendrites.  相似文献   
217.
Single-phase rare-earth gallium garnets were obtained by the reaction of stoichiometric mixtures of gallium acetylacetonate and rare-earth (Nd-Lu) acetates in 1,4-butanediol at 300°C (glycothermal reaction). Particles of gadolinium gallium garnet (GGG) and other gallium garnets with rare-earth elements larger than Gd were spherical with diameters of 0.5-2 μm, while particles of garnets with smaller rare-earth ions (Tb-Lu and Y) were much smaller (100-300 nm) with particle size distributed in a quite narrow range. TEM observation revealed that each particle was essentially a single crystal grown from one nucleus, but that defects frequently occurred during the crystal growth. Cerium and praseodymium gallium garnets were also formed when the reaction was carried out in the presence of GGG seed crystals. Hydrothermal reactions of the same starting materials under identical conditions yielded mixtures of gamma-Ga2O3 and the garnet phase.  相似文献   
218.
Boron nitride (BN) films have contributed to improvement of tribological parts. For this study, we prepared films using plasma MOCVD with an organoborate precursor and investigated the mechanical properties and structure of BN films. The BN films were formed on specimens of silicon wafers and tungsten carbide (WC) substrates at low temperatures of less than 500 °C. Hardness tests were carried out to evaluate mechanical properties of BN films. The structure of BN films was investigated using XRD, Raman, and FT-IR spectra.  相似文献   
219.
Dispersion polymerization of styrene in ethanol was carried out to encapsulate aluminum flakes. The effects of three reactive surfactants, two anionic and one nonionic, were investigated. It was confirmed prior to encapsulation that these surfactants did not polymerize by themselves but did promote polymerization of styrene. The capsules obtained were characterized with respect to the morphology and mean size. The encapsulating efficiency of the polymer of the wall material, the wall thickness, and the molecular weight distribution were measured. The effects of the concentrations of styrene monomer and reactive surfactants on these characteristics were determined and discussed. Aluminum flakes were coagulated to form secondary particles and they were covered with fine polymer particles, which were precipitated in the continuous phase. To improve encapsulation, the auxiliary addition of nonionic surfactant was attempted. By controlling those concentrations, capsules covered with polymer layer were prepared. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 675–683, 2001  相似文献   
220.
Numerical simulations of the closed‐cycle disk MHD generation experiment with Tokyo Institute of Technology's Fuji‐1 blow‐down facility are performed. In the calculations, the rz two‐dimensional time‐dependent simulation code developed by the authors that can take the effect of water contamination into account is used, and the experimental conditions of Run A4109 operated by Disk‐F4 generator are selected as the numerical conditions. When the water contamination is the lowest level realized in the experiments, the simulation results coincide with the experimental results reasonably well, though there exist some discrepancies caused by inaccuracy of used basic plasma parameters, limitations of the two‐dimensional approximation, and so on. The voltage–current curve is almost linear, indicating that the MHD interaction is relatively weak and the flow field is mainly determined by the back‐pressure. The increase of the water contamination level results in decreased seed ionization rate at the generator channel inlet, leading to the steep deterioration of the generator performance. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(2): 46–54, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10335  相似文献   
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