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排序方式: 共有96条查询结果,搜索用时 31 毫秒
51.
Yukio Akiyama Yasufumi Ueyama Seiya Hamada Akito Kubota Daisuke Kato Hitomi Yamada-Akiyama Yoshinori Takahara Masahiro Fujimori 《Breeding Science》2016,66(2):234-243
Festulolium is a hybrid between Festuca and Lolium species that has valuable agronomic traits from both grass species. The purpose of our breeding program is to produce hexaploid festulolium that introduces tolerance to summer depression into Italian ryegrass (Lolium multiflorum) by crossing it with tall fescue (Festuca arundinacea). However, we found the DNA ploidy of hexaploids was not stable and was reduced in successive generations. We aimed to find out how to obtain stable high-ploidy festulolium. F1 hybrids of L. multiflorum and F. arundinacea were produced. The F3 generation was produced from putative hexaploid F2 individuals by open pollination. The F4 to F6 generations were obtained by polycrossing. The DNA ploidy levels of F2 to F6 individuals were estimated by flow cytometry. Cytological characteristics of the F5 and F6 individuals were investigated by FISH and GISH. The DNA ploidy level of hexaploid festulolium was reduced and stabilized at almost the same level as a tetraploid. Seed fertility was inversely correlated with an increase in ploidy level. GISH revealed no preferential Lolium transmission. FISH with a telomere probe revealed that counting the exact number of chromosomes in festulolium was difficult. DNA ploidy level was strongly correlated with the number of chromosomes. 相似文献
52.
Acid rain impacts on the small forested watershed in northern Tama Hills in the western Tokyo metropolitan area Japan were investigated by surveying the trends of major inorganic species in rain and spring water during the years from 1991 to 1997. The ecosystem had been stressed by the annual H+-deposition of around 0.43 kmol/ha. The spring water outflow corresponded to ca. 27% of the precipitation. Budgets for the precipitation input and spring water output gave good balance for Cl?,?0.01 ±0.09 kmol/ha, net gains for H+, NO3 ? and SO4 2?, and to the contrary, relatively large net losses for Na+, Mg2+, Ca2+, Si(as H4SiO4) and HCO3 ?, thus suggesting the dissolution of chemical weathered products of silicate minerals. Further, in spring water, some concentration relationships were found: CNa+ = 376.5?2.05CCl? (R2=0.748), CNa+=12.69+0.5556CHCO3 ? (R2=0.872) and CH4SiO4=130.0 + 1.108CHCO3 ? (R2=0.816). Evidently, the spring water chemistry reflected probable geochemical changes in the soil layer of the watershed. Mass balance in the ecosystem and estimation of the spring water output of chemical weathered products were investigated 相似文献
53.
Nakagawa I Amano A Mizushima N Yamamoto A Yamaguchi H Kamimoto T Nara A Funao J Nakata M Tsuda K Hamada S Yoshimori T 《Science (New York, N.Y.)》2004,306(5698):1037-1040
We found that the autophagic machinery could effectively eliminate pathogenic group A Streptococcus (GAS) within nonphagocytic cells. After escaping from endosomes into the cytoplasm, GAS became enveloped by autophagosome-like compartments and were killed upon fusion of these compartments with lysosomes. In autophagy-deficient Atg5-/- cells, GAS survived, multiplied, and were released from the cells. Thus, the autophagic machinery can act as an innate defense system against invading pathogens. 相似文献
54.
Ikeda I Kobayashi M Hamada T Tsuda K Goto H Imaizumi K Nozawa A Sugimoto A Kakuda T 《Journal of agricultural and food chemistry》2003,51(25):7303-7307
It has been known that tea catechins, (-)-epicatechin (1), (-)-epigallocatechin (2), (-)-epicatechin gallate (3), and (-)-epigallocatechin gallate (4) are epimerized to(-)-catechin (5), (-)-gallocatechin (6), (-)-catechin gallate (7), and (-)-gallocatechin gallate (8), respectively, during retort pasteurization. We previously reported that tea catechins, mainly composed of 3 and 4, effectively inhibit cholesterol absorption in rats. In this study, the effect of heat-epimerized catechins on cholesterol absorption was compared with tea catechins. Both tea catechins and heat-epimerized catechins lowered lymphatic recovery of cholesterol in rats cannulated in the thoracic duct and epimerized catechins were more effective than tea catechins. The effect of purified catechins on micellar solubility of cholesterol was examined in an in vitro study. The addition of gallate esters of catechins reduced micellar solubility of cholesterol by precipitating cholesterol from bile salt micelles. Compounds 7 and 8 were more effective to precipitate cholesterol than 3 and 4, respectively. These observations strongly suggest that heat-epimerized catechins may be more hypocholesterolemic than tea catechins. 相似文献
55.
A newly constructed optical measurement system was introduced to nondestructively measure the composition of the inside of an apple by time-of-flight near-infrared spectroscopy (TOF-NIRS). As sugar content increased, optical parameters concerned with time-resolved profile of transmitted pulsed light (the attenuance of peak maxima, At, the time delay of peak maxima, Deltat, and the variation of full width at half-maximum, Deltaw) decreased gradually. When the acid content increased, At and Deltaw increased; however, a significant tendency could not be found for Deltat. At, Deltat, and Deltaw were employed as the explanatory variables for multiple linear regression, principle component regression, and partial least-squares analysis. It was possible to predict both sugar and acid contents in an apple with high precision by TOF-NIRS. Especially, the superiority of TOF-NIRS lied in more precise determination of acid content. 相似文献
56.
Katsuyoshi Hamada Yuji Tsutsumi Kazuchika Yamauchi Kazuhiko Fukushima Tomoaki Nishida 《Journal of Wood Science》2003,49(4):333-338
Ferulic acid (FA), tetradeuteroferulic acid (DFA), sinapic acid (SA), or heptadeuterosinapic acid (DSA) was exogenously supplied to poplar (Populus alba L.) callus. Administration of FA or SA increased the lignin content of the callus to about twice that of the control callus. Gas chromatographic analysis of the alkali hydrolysate of the cell wall residue revealed that only a trace amount of SA was bound to the cell wall, and the amount of FA was less than 2% of the total callus lignin. Thioacidolysis of the DFA-treated callus indicated that DFA is effectively converted to both coniferyl and sinapyl alcohols and then incorporated into the corresponding lignin. Incorporation of DSA into syringyl lignin or guaiacyl lignin was not observed, but yields of syringyl lignin thioacidolysis products were markedly increased by DSA treatment of the callus. These results suggest that SA may not be a precursor of sinapyl alcohol and syringyl lignin per se, but it may induce or enhance the biosynthesis of syringyl lignin in poplar callus. 相似文献
57.
Yasuhiro Tanoue Akira Terada Kazunori Sakata Mamoru Hashimoto Shin-Ichi Morishita Moritugu Hamada Norihisa Kai 《Fisheries Science》2001,67(4):726-729
ABSTRACT: A facile synthesis of Tyrian purple, a valuable purple dye derived from gastropod mollusks in ancient times, has been accomplished. Tyrian purple, 6,6'-dibromoindigo, was easily obtained by three steps of reactions from the commercially available 6-bromoindole, on the basis of a biosynthetic pathway of indigo and biological precursors of the purple. Iodination of 6-bromoindole, followed by acetoxylation with silver acetate in acetic acid, afforded 6-bromo-3-acetoxyindole, whose alkaline hydrolysis accompanying air oxidation produced Tyrian purple. 相似文献
58.
59.
60.
Qu C Kishimoto T Kishino M Hamada M Nakajima N 《Journal of agricultural and food chemistry》2011,59(10):5382-5389
An ionic liquid, 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), was used to dissolve Japanese fir (Abies sachallnensis MAST) wood. Milled woods prepared by planetary ball-milling for 8 h dissolved completely in [Bmim]Cl at 100 °C in 2 h. The dissolved woods were then subjected to in situ acetylation, and the fully acetylated woods were regenerated from [Bmim]Cl. (1)H-(13)C correlation heteronuclear single-quantum coherence (HSQC) nuclear magnetic resonance (NMR) experiments were successfully conducted with the acetylated woods in dimethyl sulfoxide (DMSO)-d(6). The acetylated lignin and polysaccharide signals dispersed reasonably well on the 2D spectra. Characterization of the NMR signals for the whole cell-wall components, including lignin, cellulose, and hemicelluloses, was achieved by comparison with isolated lignin and commercial cellulose and hemicelluloses (arabinoxylan, galactomannan, and glucomannan). The procedure used here is applicable for the characterization of cell-wall components in various plant biomasses. 相似文献