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991.
Jun Yano Kenta Suzuki Chikara Tsutsumi Michiaki Mabuchi Akira Kitani 《Bioscience, biotechnology, and biochemistry》2013,77(11):1849-1854
ABSTRACTBoth light and a redox mediator riboflavin (RF) were utilized to promote the electro-oxidation of an NADH model compound (1-benzyl-1,4-dihydronicotinamide, BNAH), which is a key process for enzymatic biofuel cells to obtain a high performance. At the cathode, H+ ions were simultaneously reduced to produce H2 gas. To elucidate the cell reactions of this photogalvanic cell, which is significant information about the fabrication of enzymatic biofuel cells with a high performance, the effect of the BNAH and RF concentrations on the cell current, the light wavelength dependence on the current, and reduction of the RF concentration were evaluated. The obtained results strongly suggest that the anodic reactions were composed of the following reactions: 1) the photo-excitation of RF, 2) the attack of the excited RF on the BNAH and the generation of the radical species of BNAH and RF, and 3) the chain reactions between the radical species. 相似文献
992.
Sin-ich Sugiyama Keiji Yano Kazuo Komagata Masaji Kazama Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(2):211-216
The metabolic products of m-hydroxybenzoic acid formed by certain Pseudomonas, Micrococcus, and Bacterium strains which possess oxidizing ability of this acid were detected by paperchromatography. It was recognized that protocatechuic acid or gentisic acid are intermediary metabolites of m-hydroxybenzoic acid by these bacteria and the both acids are not detected in one cultural broth. 相似文献
993.
Takeshi Sakaki Katsuya Fukuhara Katsuko Niino Hirohiko Sakuma Shiro Sugawara 《Bioscience, biotechnology, and biochemistry》2013,77(6):1785-1791
In order to investigate the headspace volatiles which indicate the againg effect on tobacco, the headspace volatiles of Japanese flue-cured tobacco were collected by active carbon and analyzed by gas chromatography. The data obtained were subjected to principal component analysis (PCA) and stepwise discriminant analysis (SDA). The results of PCA showed that the volatiles indicated the effect of aging on smoking quality. The SDA selected six peaks of the volatiles which classified the samples into four groups according to the aging period. The results described above can show that the relative proportions of the volatiles, such as furfuryl alcohol, benzyl alcohol and solanone, may be used to judge approximately the agint effects on tobacco. 相似文献
994.
Populations of Astyanax paranae, Astyanax fasciatus and Astyanax altiparanae collected from the Pindorama and Lopei streams (upper Paraná river basin, Brazil) were cytogenetically studied, checking for chromosomal differentiation and the evolutionary trend in the three species. Forty-eight chromosomes (8m + 20sm + 10st + 10a) were observed in both populations of Astyanax paranae. Astyanax fasciatus exhibited 50 chromosomes (8m + 18sm + 10st + 14a, Pindorama stream; 8m + 14sm + 12st + 16a, Lopei stream). The diploid number for A. altiparanae was 50 chromosomes in both populations (6m + 30sm + 4st + 10a). The three studied species exhibited multiple AgNORs with differences among the populations of A. paranae and A. fasciatus. Regarding the heterochromatin distribution, interpopulational differences were observed in the three species. The data of the present study demonstrate that both A. paranae and A. fasciatus exhibit karyotypical interpopulational differences more conspicuous than A. altiparanae populations, probably due to the characteristics that restricted both the A. paranae and the A. fasciatus to the upper portion of the streams, leading to the fixation of different chromosomal rearrangements in the populations. However, the absence of conspicuos interpopulational karyotypical differences in A. altiparanae suggests a gene flow between both populations. In the present study, the role of the streams as an environment which maintains the diversity of fish with different genetic pools became evident. 相似文献
995.
Jai-Yul Kong Sadaaki Iibuchi Osato Miyawaki Toshimasa Yano 《Bioscience, biotechnology, and biochemistry》2013,77(5):1235-1241
Published data of the effective thermal conductivities of meats were analyzed in relation to approximate compositions of the meats. On the basis of series heat conduction model, the “intrinsic” thermal conductivity value of meat protein was estimated to be 0.342 [W/m · °C] when unfrozen, and 0.581 [W/m · °C] when frozen. Using these “intrinsic” values and the series heat conduction model, the effective thermal conductivities of meats were reversely predicted from the contents of water and fat. Standard deviations of the published data from the predictions were ± 7.0% for unfrozen meats and ± 15.4% for frozen meats. If heat flow is parallel to the meat grain, published data for frozen meats are higher than the predictions by about 20% as a mean. 相似文献
996.
997.
Susceptibility of T-cell-mediated cytotoxicity to X irradiation was examined in the stages of induction and expression. C3H/He mice and a methylcholanthrene-induced sarcoma of C57BL/6 origin were used for experiments. (i) Established cytotoxicity was radioresistant. (ii) Irradiation of hosts before tumor inoculation suppressed induction of cytotoxicity. Irradiation at 3 hr after tumor inoculation or later did not affect induction of cytotoxicity. (iii) Cytotoxicity became detectable on day 7 but not on day 3, when mice were irradiated 3 hr after tumor inoculation, (iv) Tumor resection abolished cytotoxicity when carried out 24 hr after tumor inoculation but not when carried out on day 3 or later. (v) Sonicated antigen of tumor cells proved to be effective in raising the radioresistant state in the hosts, since cytotoxicity was detectable in those given irradiation 3 hr and viable tumor cells 6 hr after the priming. The radioresistant nature of cytotoxicity may be acquired within a very short period after immunization. However, development of killer cells from such a radioresistant state requires further antigen stimulation with viable tumor cells for a limited period, and maturation of such cells requires some latent period thereafter. 相似文献
998.
This report examines the plant traits that effect the community structure of herbivorous insects on wild crucifers. Wild crucifers were classified into 4 types (A, B, C, D) according to their phenology. Type A and B plants had a pausing phenology, disappearing in the middle of the insects' active season, while type C and D plants had a continual phenology, existing all year long. The intrinsic quality of the plants as food, which was assessed by measuring the performance of herbivores, was superior in type A, B and D plants, while it was inferior in type C. The phenology and intrinsic quality were the alternative means of direct defense mechanisms against herbivorous insects: The plants with a pausing phenology were intrinsically superior (A, B), while the plants with a continual phenology were intrinsically inferior (C). However, there were a few plants with continual phenology and superior intrinsic quality (D, the type B plants that remained in the summer). Within the community of the herbivorous insects on the plants with direct defense mechanisms, the number of species and individuals was small and most of the community members were specialists of the plants. On the other hand, within the community on plants without direct defense mechanisms, the number of species was large and the proportion of generalists was high. In addition, the number of individuals was very large on the remaining type B plants, but it was small on type D plants, which were inferred to have indirect defense mechanisms. 相似文献
999.
Kazunari Yano 《Ichthyological Research》1993,39(4):345-356
Three hundred and seventy-three females and 385 malesof Gollum attenuatus were caught with bottom longlines from the Challenger Plateau, Wanganella Bank and Three Kings Ridge around New Zealand. The sharks ranged in size from 440 to 1092 mm TL for females and 442 to 1067 mm TL for males. Catch rates (number of fish per 100 hooks) were 0.41 for the Challenger Plateau, 0.14 for the Wanganella Bank, and 4.52 for the Three Kings Ridge. The sex ratio was 1:1. In terms of 100-m depth intervals,G. attenuatus was most abundant in 500 to 599 m depths. There was a marked decrease in catch rates with increased distance of the hooks from the bottom. Stomachs contained such varied items as sharks, teleost fishes, gastropods, squids, octopi, decapods, isopods, brittle stars, and human garbage. The data in this study suggest thatG. attenuatus consumed, in order of importance, fishes and crustaceans. 相似文献
1000.
The possible involvement of protein phosphatase 1 in thrombin-induced Ca2+ influx of human platelets
Kouhei Murata Masato Sakon Jun-Ichi Kambayashi Masao Yukawa Yoshiko Yano Kazumasa Fujitani Tomio Kawasaki Eiichi Shiba Takesada Mori 《Journal of cellular biochemistry》1993,51(4):442-445
Protein phosphatase 1 is considered to be involved in thrombin-induced platelet activation (Murata et al., Biochem Int 26:327–334, 1992). To clarify the mechanism, we examined the effects of protein phosphatase 1 and 2A inhibitors (calyculin A, tautomycin, okadaic acid) on Ca2+ influx. In the presence of 1 mM Ca2+, thrombin- (0.1 U/ml) induced platelet aggregation and ATP release were inhibited by calyculin A, while this inhibitory effect was abolished in the absence of Ca2+ (EGTA 1 mM). Furthermore, thrombin-induced Mn2+ influx but not intracellular Ca2+ mobilization was inhibited by calyculin A in a dose-related manner. Calyculin A also blocked the ongoing Ca2+ influx when added 3 min after thrombin stimulation. Similar inhibitory effects were observed with okadaic acid and tautomycin in the same potency sequence as the reported one for protein phosphatase 1 (calyculin A > tautomycin > okadaic acid). These results suggest that the anti-platelet effects of phosphatase inhibitors are due to the inhibition of Ca2+ influx and that protein phosphatase 1 plays a key role in the regulation of receptor operated Ca2+ channel of human platelets. 相似文献