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41.
K Yamada K Senzaki Y Komori T Nikai H Sugihara T Nabeshima 《Canadian Metallurgical Quarterly》1997,762(1-2):72-78
The role of glial cells in nitric oxide production in the cerebellum of conscious rats was investigated with a glial selective metabolic inhibitor, fluorocitrate. The levels of nitric oxide metabolites (nitrite plus nitrate) in the dialysate following in vivo microdialysis progressively increased to more than 2-fold the basal levels during a 2-h infusion of fluorocitrate (1 mM), and the increase persisted for more than 2 h after the treatment. Pretreatment with N(G)-nitro-L-arginine methyl ester attenuated the fluorocitrate-induced increase in nitric oxide metabolite levels. None of the glutamate receptor antagonists, including D(-)-2-amino-5-phosphonopentanoic acid, 6,7-dinitroquinoxaline-2,3-dione, and (+/-)-alpha-methyl-4-carboxyphenylglycine, inhibited the fluorocitrate-induced increase. The L-arginine-induced increase was significantly reduced by fluorocitrate treatment, while N-methyl-D-aspartate, (+)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid, and trans-(+/-)-1-amino-(1S,3R)-cyclopentane-dicarboxylic acid increased nitric oxide metabolites levels in the fluorocitrate-treated rats, as much as in control animals. These results suggest that glial cells play an important role in modulating nitric oxide production in the cerebellum by regulating L-arginine availability. 相似文献
42.
Using spin-on glass (SOG) as an adhesive, an Si wafer with thermal oxide was successfully bonded to one with an RF-sputtered Si3N4 film. This ensures that SOG films are effective in bonding Si wafers to less reactive surfaces than Si or SiO2 such as silicon nitride. It was also found that the previously reported bonding procedure can be simplified by suppressing the spin-induced radial striations of the SOG films. 相似文献
43.
A GalnAsP edge-detecting photodiode was coupled with an SiO2-TiO2 single-mode waveguide in a simple hybrid integration scheme. The newly developed edge-detecting photodiode with a window region was used to improve photodiode durability. 相似文献
44.
In male Syrian hamsters, short days induce regression of the reproductive system, but eventually spontaneous recrudescence occurs ensuing from refractoriness to the inhibitory photoperiod. Although the photoperiod of 12 L:12 D (12 h light:12 h dark) may act like a short day by inducing the testicular cycle outlined above, it may fail to evoke the increase of circulating concentrations of prolactin that accompanies testicular recrudescence. This photoperiod may fail to induce photorefractoriness, as indicated by the prolonged low concentrations of prolactin in the blood. Herein, hamsters were exposed to either 8 L:16 D or 12 L:12 D from weaning and by 28 weeks exposure to either photoperiod, the hamsters had large testes following recrudescence from a photoperiod induced-regression). Transfer to 8 L:16 D from 12 L:12 D at 28 weeks resulted in a second testicular regression and recrudescence. In a second experiment, the testes of hamsters moved to 8 L:16 D from 12 L:12 D after 29 weeks exposure to the latter photoperiod similarly regressed and then regrew. Serum concentrations of prolactin decreased in these males after transfer to the shorter daylength but also decreased in hamsters kept under 12 L:12 D both groups were usually below those of hamsters moved to 14 L:10 D. These results show that exposure for 28 or 29 weeks to 12 L:12 D was insufficient to induce photorefractoriness, despite the recrudescence of the testes following involution. 相似文献
45.
H Komuro MB Valentine ST Rowe VJ Kidd S Makino GM Brodeur SL Cohn AT Look 《Canadian Metallurgical Quarterly》1998,33(11):1695-1698
Artificial illumination is an important factor in the management of layers. In this study, a new monochromatic light system was developed for egg layers. Prelaying pullets (Lohmann) were marked and housed in nine light and temperature control rooms (15 battery cages, 3 hens per cage; n = 45), divided into three light treatments: 0.1 and 0.01 W/m2 light intensity using light emitting diode (LED) lamps and 0.1 W/m2 using mini-fluorescent bulbs (PL) (control). In each of the LED rooms, three wavelengths were tested: 560 (n = 9), 660 (n = 9), 880 (n = 6), and 660 intermitted lighting (15 min light 45 min dark, 660IN) (n = 9). Birds were exposed to 12 h light and 12 h of darkness using PL lamps. At 21 wk of age, the light period was increased to 12.75 h by using 5.5 h of LED lamps and 7.25 of PL light source for Groups 1 and 2, the third group received 12.75 h of PL light. Until 28 wk of age, light hours increased by 0.5 h/w using LED light for Groups 1 and 2 and PL source for the third group, reaching 16 h of light at 28 wk of age. Egg production and feed consumption were recorded daily; egg components were recorded weekly for 10 mo. A significant reduction in egg production was observed in all 880nm groups; no differences in egg production and quality were found in the other groups. Feed consumption was significantly lower by 7% in all 0.01 W/m2 groups. We suggest that an important reduction in rearing costs of laying hens may be obtained by using this system. 相似文献
46.
Hiroyuki Nakahira Masakatsu Maruyama Hideshi Ueda Haruyasu Yamada 《The Journal of VLSI Signal Processing》1993,5(2-3):133-140
This paper describes an image processing system using Image Signal Multiprocessors (ISMPs) adapted to gray-level image preprocessing for image analysis and image enhancement. It is composed of four ISMPs, five 1H-delay-lines, two 512×512×8-bit frame memories, a video timing controller (VTC), two 256-word ×8-bit ×8-table Look Up Tables (LUTs) and 80 nsec/sampling A/D and D/A converters. This multiprocessor system performs convolution operations such as spatial filters, contrast enhancement, and binarization for gray-level images, thinning, thickening, pattern matching etc. for binary images, and image quality improvement for moving images such as T.V. images. Otherwise, it performs feature extraction operations such as area calculations, fillet coordination, and moment calculations for objective image data. Moreover, this system is capable of applying color image processing by using a multiboard system. 相似文献
47.
Takada K. Kitagawa T. Hattori K. Yamada M. Horiguchi M. Hickernell R.K. 《Electronics letters》1992,28(20):1889-1891
The group delay and dispersion, including the erbium ion contributions, of the highly erbium-doped silica planar waveguide amplifier and multicomponent glass fibre amplifiers are directly measured at different pump powers using a low coherence reflectometer and dispersive Fourier spectroscopy. This method derives the refractive index spectra of these amplifiers directly from the produced reflectograms without any physical or mathematical assumptions. The dispersion of the planar waveguide amplifier at 500 mW pumping changes between +300 and -200 ps/km/nm with a 0.4 wt.% erbium concentration.<> 相似文献
48.
Various aspects of our communication are well known to have changed over time (1-3). This article describes a cross-sectional study that examined the acoustic characteristics of two groups of Australian women aged 18-25 years from recordings made in 1945 and 1993 and investigated the possible changes in the voice across generations. Archival recordings from 1945 which had been used in a longitudinal study (4) were compared to recordings made in 1993. The results of this study show that women in 1993 have significantly deeper voices than women of the same age recorded in 1945. The possible factors influencing this change are discussed. 相似文献
49.
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