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71.
Reo Etani Takahiro Kataoka Yuichi Nishiyama Yuji Takata 《Journal of Nuclear Science and Technology》2013,50(12):1512-1518
It has been reported that radon inhalation activates antioxidative functions in liver and has an antioxidative effect against hepatopathy similar to that of the antioxidative effects of ascorbic acid (VC) or α-tocopherol (VE). In this study, we examined the combined effects of radon inhalation and antioxidant vitamin administration on acute alcohol-induced hepatopathy in mice. ICR mice were subjected to intraperitoneal (i.p.) administration of alcohol after pretreating with air only (sham) or radon at a concentration of approximately 2000 Bq/m3 for 24 hours and i.p. administration of VC (300 mg/kg body weight) or VE (300 mg/kg body weight). In mice injected with alcohol, the combined radon and antioxidant vitamins treatment significantly decreased the activities of glutamic oxaloacetic transaminase in serum compared to not only the alcohol-administered group (sham group), but also the radon inhalation with alcohol administration group or the vitamin and alcohol administration group. In addition, radon inhalation significantly increased the antioxidant level, in such as the catalase activity and the total glutathione content in liver compared to the sham group. These results suggested that the combined radon and antioxidant vitamin treatment could effectively inhibit alcohol-induced hepatopathy in mice without any antagonizing action. 相似文献
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74.
T Moriguchi H Matsuura Y Itakura H Katsuki H Saito N Nishiyama 《Canadian Metallurgical Quarterly》1997,61(14):1413-1420
Effects of allixin, a phytoalexin of garlic, and its analogues were studied on the survival and morphology of primary cultured neurons from fetal rat brain. Addition of allixin (1-100 ng/ml) to medium significantly promoted the survival of neurons derived from various regions of brain and increased the number of branching points per axon in hippocampal neurons. Allixin, however, was cytotoxic at higher concentrations (>1 microg/ml). Among the analogues of allixin, 2,6-dimethyl-3-hydroxy-4H-pyran-4-one (DHP) possessed potent neurotrophic activity at concentrations over 10 ng/ml without any obvious cytotoxicity up to 10 microg/ml. DHP also retained the activity to promote axonal branching. These results indicate that DHP is a novel exogenous low molecular weight neurotrophic substance without apparent cytotoxicity. This compound may be a useful prototype leading chemical for developing therapeutic and/or prophylactic drugs for neurodegenerative disorders. 相似文献
75.
AH Koyama H Akari A Adachi F Goshima Y Nishiyama 《Canadian Metallurgical Quarterly》1998,143(12):2435-2441
Although herpes simplex virus type 1 (HSV-1) does not induce apoptosis in infected HEp-2 cells, herpes simplex virus type 2 (HSV-2) did induce apoptosis in a small but significant fraction of the same cells. Apoptosis was not observed in Vero or HeLa cells infected with HSV-2. In addition, HSV-2 infection in the presence of cycloheximide induced extensive apoptosis of HEp-2 or HeLa cells. 相似文献
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77.
Nakao K. Obana S. Nishiyama S. Tanaka T. 《Selected Areas in Communications, IEEE Journal on》1990,8(1):80-92
Results are presented of a study of the feasibility realizing a real-time information retrieval service operating between different worldwide videotex systems by means of gateway facilities that use conversion of data syntax and processing of the videotex information structure. Two separate evaluations were carried out, both using response time as the performance criterion. One was for communication processes at both of two gateways, and the other was for data syntax conversion at the local host. Both approaches are considered as kernel functions in the gateway system. The results of each evaluation were favorable in the sense that response time for the total system using gateways compared favorably to the response time in direct videotex access over the packet-switched public data network 相似文献
78.
Summary
Introduction of simple alkyl groups at the C-2 nitrogen of chitin and some properties of the resulting N-alkyl-chitins have been examined. Chitosan was fully deacetylated and treated with three kinds of aldehydes, formaldehyde,
acetaldehyde, and pentanal. The Schiff bases of chitosan, whose extents of substitution were dependent on the amount of aldehydes,
were reduced with sodium cyanoborohydride to N-alkylated chitosans. The N-alkyl-chitosans were then transformed into the corresponding N-alkyl-chitins by acetylation with acetic anhydride followed by transesterification to remove partly formed O-acetyl groups. The resulting N-methyl-, ethyl-, and pentyl-chitins were amorphous and showed improved affinity for organic solvents.
Received: 13 December 2001/Revised version: 11 January 2002/Accepted: 17 January 2002 相似文献
79.
T Moriguchi H Matsuura Y Kodera Y Itakura H Katsuki H Saito N Nishiyama 《Canadian Metallurgical Quarterly》1997,22(12):1449-1452
Several organosulfur compounds found in garlic extract promoted the survival of rat hippocampal neurons in vitro. From the analysis of structure-activity relationship, thioallyl group in these compounds is essential for the manifestation of neurotrophic activity. S-Allyl-L-cysteine (SAC), one of the organosulfur compounds having thioallyl group in garlic extract, also promoted the axonal branching of cultured neurons. These results suggest that thioallyl compounds make a unique group of neurotrophic factors. 相似文献
80.
Most food materials are usually measured in three mutually perpendicular dimensions (length, width, and thickness) and considered approximately as general ellipsoids. In this article, we briefly reviewed the available studies on how to deal with the diffusion problems in ellipsoidal solids. A three-dimensional (3-D) model was proposed to accurately represent the kernel geometry and rigorously interpret the diffusion phenomena. By the finite difference method, the numerical solution of the diffusion equation for kernels of different shape factors was obtained and compared with those predicted by the one-dimensional (sphere) model and two-dimensional (axi-symmetrical body) model. Meanwhile, the effectiveness of the latter two models was evaluated. 相似文献