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991.
K Ikemoto I Nagatsu K Kitahama A Jouvet A Nishimura K Nishi T Maeda R Arai 《Canadian Metallurgical Quarterly》1998,243(1-3):129-132
The human basal forebrain has been known to contain many neurons immunoreactive (ir) to tyrosine hydroxylase (TH; the first dopamine-synthesizing enzyme). We examined whether these neurons might contain aromatic L-amino acid decarboxylase (AADC; the second step dopamine-synthesizing enzyme) by dual labeling immunohistochemistry and confocal laser-scanning microscopy. Neurons dually-labeled for TH and AADC were found in the anterior olfactory nucleus, olfactory tubercle and the ventral margin of the rostral nucleus accumbens. The examination in the basal forebrain of the macaque monkey also gave substantially the same results. These neurons appear to constitute an independent dopaminergic cell group in the primate basal forebrain. 相似文献
992.
Vladimir V. Plashnitsa Taro Ueda Norio Miura 《International Journal of Applied Ceramic Technology》2006,3(2):127-133
Nano-sized NiO powder was modified by the addition of BaO, La2 O3 , and CuO (10 wt% each) to change its morphology and electrochemical catalytic activities. Then, the NO x -sensing characteristics of mixed-potential-type YSZ-based planar sensor attached with each of the obtained NiO-based samples as a sensing electrode (SE) were examined at elevated temperatures. As a result, the CuO-added NiO SE was found to give a large enhancement in the NO2 sensitivity as well as the NO2 selectivity at 800°C even under a wet condition, in comparison with the pure NiO SE. 相似文献
993.
Kazutoshi Kojima Satoshi Kuroda Hajime Okumura Kazuo Arai 《Microelectronic Engineering》2006,83(1):79-81
We have reinvestigated the characteristics of N and Al doping on 4H-SiC epitaxial layer. It was found that thermally activated process and desorption process are aspects of the mechanism of the N incorporation to which attention should be paid. The process strongly depends on the lattice polarity and C/Si ratio. Thermally activated process dominates the N incorporation of the Si-face under the high C/Si ratio. Under the low C/Si condition, the desorption process dominates the N incorporation of the Si-face. For C-face, the desorption process dominates the N incorporation regardless of the lattice polarity and the C/Si ratio. Concerning Al doping, the desorption process dominates the Al incorporation without reference to the lattice polarity and the C/Si ratio. 相似文献
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997.
H Arai FS Monteclaro CL Tsou C Franci IF Charo 《Canadian Metallurgical Quarterly》1997,272(40):25037-25042
To investigate the role of the carboxyl-terminal region (52 amino acids) of the monocyte chemoattractant protein 1 receptor (CCR2B) in chemotaxis, we created a series of mutants and expressed them in a murine pre-B lymphocyte cell line. Truncation of the cytoplasmic carboxyl tail to 20 amino acids had little or no effect on chemotaxis or signal transduction, but further truncation resulted in marked functional defects. Upon incubation with monocyte chemoattractant protein 1, CCR2B underwent rapid and extensive internalization, and this was impaired progressively as the carboxyl tail was truncated from 52 to 8 amino acids. Mutation of all of the serine and threonine residues in the carboxyl tail to alanine also resulted in markedly impaired receptor internalization but did not affect signaling or chemotaxis. We conclude that the membrane-proximal portion of the cytoplasmic carboxyl tail of CCR2B is critically involved in chemotaxis and signal transduction, but neither phosphorylation of carboxyl serines or threonines nor internalization of the receptor is required for robust chemotaxis. 相似文献
998.
Hisayuki Nakatani Norio Manabe Yoshimitsu Yokota Hiroaki Minami Shoutarou Suzuki Fumitaka Yamaguchi Minoru Terano 《Polymer International》2007,56(9):1152-1158
Thermal oxidative degradation of polypropylene impact copolymer has been studied with its fractions obtained using the temperature rising elution fractionation method. The fractions were analyzed using 13C NMR, Fourier transform infrared and differential scanning calorimetry measurements, and the chemical structure, isotacticity, conformation and melting point were investigated. It is found that these fractions are composed of a homopolymer or a polymer blend of polypropylene, polyethylene and ethylene–propylene copolymer. The thermal oxidative degradation of each fraction was carried out at 130 °C, and the degradation progress was estimated by the change of molecular weight distribution (from gel permeation chromatography curves). The rate of degradation is found to be dominated by the content of tertiary C? H bonds (propylene unit) and the existence of 31 helix conformation corresponding to a crystalline polypropylene part in each fraction. The latter is more evident leading to the degradation reaction path with a lower activation energy. Copyright © 2007 Society of Chemical Industry 相似文献
999.
N Takemoto N Koyano-Nakagawa T Yokota N Arai S Miyatake K Arai 《Canadian Metallurgical Quarterly》1998,10(12):1981-1985
IL-4 and IL-13 are cytokines preferentially produced by Th2 cells, and their genes are located in close proximity on human chromosome 5 and mouse chromosome 11. To identify potential regulatory elements that confer Th2-specific expression of IL-4 and IL-13 genes, we constructed a physical map of the IL-13/IL-4 locus and conducted DNase I-hypersensitive (DH) site analysis using Th clones and in vitro-differentiated effector Th cells obtained from TCR transgenic mice. Three DH sites, HSS1, HSS2 and HSS3, were identified within the intergenic region between IL-13 and IL-4 genes. HSS3 was observed both in Th1 and Th2 cells as well as CD4+ naive T cells, while HSS1 and HSS2 were detected exclusively in Th2 cells. The correlation between differentiation into Th2 subtype and the appearance of HSS1 and HSS2 suggests that these regions may play a role in subtype-specific expression of the IL-13/IL-4 locus. 相似文献
1000.
In order to examine the relation between damage evolution and changes in microstructure, e.g. from creep cavities, surface micro-cracks and dislocation structures at high temperature, strain controlled creep-fatigue tests were performed and interrupted at several damage levels on Types 304 and 316 stainless steels. The creep-fatigue tests on Type 304 stainless steel at a low strain level were conducted in a high-temperature fatigue testing machine combined with a scanning electron microscope, and the micro-crack initiation and growth behaviour were continuously observed to clarify the damage extension mechanism. It was found that even though many cavities were initiated and grew on the internal grain boundaries of the specimens during the strain-controlled tests, the failure life was governed by the propagation of surface cracks. On the other hand, micro-cracks of about the order of one grain size were initiated mainly along grain boundaries normal to the loading axis under low stress creep-fatigue, and the crack propagation rate of the micro-cracks was slow and random due to the nature of the microstructures. The micro-cracks gradually opened in the loading direction with increasing number of cycles and coalescence contributed to growth. 相似文献