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181.
Metabolic pathways for the oxidation of 1-tetradecene by Candida lipolytica were investigated and compared with those for Candida tropicalis in order to elucidate the difference in the productivity of citrates reported in the previous paper. No difference was found in the pathways for the initial stage of oxidation of 1-tetradecene between the two strains, indicating that the difference in the productivity of citrates is not attributable to the metabolic pathways. The metabolic rate of 1-tetradecene with C. lipolytica was found to be much lower than that with C. tropicalis. The production of citrates was much enhanced in the presence of surfactants which were known to be stimulative for microbial metabolism of hydrocarbons and 11 ~ 15 g/liters was attained on the 6th day of cultivation. 相似文献
182.
183.
N Tanaka N Sekiya M Hattori H Goto N Shibahara Y Shimada K Terasawa 《Phytomedicine》2003,10(2-3):122-126
Using a high-performance liquid chromatographic method and mass spectrometry analysis, we successfully measured the absorption of orally administered procyanidin B-2 and procyanidin B-3 isolated from Cinnamonomi cortex (the bark of Cinnamomum cassia Blume) in the rat plasma. This method used a TSK- GEL ODS-80TS column, two solvents (A: 0.01% acetic acid; B: methanol with 0.01% acetic acid) in a linear gradient at a flow-rate of 1.0 ml/min, and fluorescence detection at excitation and emission wavelengths of 220 and 327 nm. 相似文献
184.
Iimura S Uoto K Ohsuki S Chiba J Yoshino T Iwahana M Jimbo T Terasawa H Soga T 《Bioorganic & medicinal chemistry letters》2001,11(3):407-410
To improve cytotoxicity of 10-deoxy-10-C-morpholinoethyl docetaxel analogues against various tumor cell lines including resistant cells expressing P-glycoprotein (P-gp), we modified the 7-hydroxyl group to hydrophobic groups (methoxy, deoxy, 6,7-olefin, alpha-F, 7-beta-8-beta-methano, fluoromethoxy). Among these analogues, the 7-methoxy analogue showed the strongest cytotoxicity. This analogue showed potent activity against B16 melanoma BL6 in vivo by oral administration. 相似文献
185.
Tree-ring (TR) chronologies are important instruments for the dating and provenance analyses of historical wood, as well as for climate reconstructions. However, radial growth patterns differ between tree species and growing environments. Therefore chronologies are more or less specific for a certain tree species, region and elevation. Chronologies that are restricted to more confined regions could extend the possibilities for dating, dendroprovenancing and regional climate reconstructions.In Southern Germany, the transport of wood by raft – for the supply of towns and cities with timber – has been documented since early mediaeval times. Consequently, not only local timber from the lowlands was used for construction purposes, but also alpine wood originating from sites up to the timberline. Since pronounced altitudinal gradients cause distinct climate differences, elevation-specific chronologies have the potential to improve dating precision in this region.In this contribution, a model is presented and applied in order to separate elevation-specific provenances of Norway spruce (Picea abies L. Karst) and Silver fir (Abies alba Mill.) in Southern Germany. The model is derived from more than 2100 living TR series originating from sites between 200 and 1710 m above see level. Absolute (mean, maximum) ring-width values and the variation of ring-widths (mean sensitivity) show distinct correlations with their altitudinal provenance, reflecting improvements in growth conditions as well as the increase of their yearly variation from high over intermediate to low elevation sites. Mean ring widths and mean sensitivity values were used as independent parameters in an exponential regression model which exhibits a coefficient of determination (r2) of 77% for spruce and 74% for fir. The prediction accuracy of the elevation amounts ±300 m for spruce and ±200 m for fir within the 95% confidence interval.The model was used to estimate the elevation origin of around 5000 historical spruce and 800 historical fir series from buildings located in Southern Germany. The historical TR series covering the AD 990–1800 period were allocated by the model to elevations between 120 and 2090 m. In a second step the individual TR series were combined to elevation-specific chronologies representing low, intermediate, and high altitudinal belts. The chronologies show distinct differences among the altitudinal belts in terms of signatures and pointer years, especially for spruce. Elevation-specific chronologies are assumed to amplify the dating possibilities of ancient timber, to provide valuable evidences for the origin of historical wood, and to offer more specific proxy data for regional climate reconstructions. 相似文献
186.
187.
Takumi Ueda Naoko Nomoto Masamichi Koga Hiroki Ogasa Yuuta Ogawa Masahiko Matsumoto Pavlos Stampoulis Koji Sode Hiroaki Terasawa Ichio Shimada 《The Plant cell》2012,24(10):4173-4186
In the photosynthetic light reactions of plants and cyanobacteria, plastocyanin (Pc) plays a crucial role as an electron carrier and shuttle protein between two membrane protein complexes: cytochrome b6f (cyt b6f) and photosystem I (PSI). The rapid turnover of Pc between cyt b6f and PSI enables the efficient use of light energy. In the Pc-cyt b6f and Pc-PSI electron transfer complexes, the electron transfer reactions are accomplished within <10−4 s. However, the mechanisms enabling the rapid association and dissociation of Pc are still unclear because of the lack of an appropriate method to study huge complexes with short lifetimes. Here, using the transferred cross-saturation method, we investigated the residues of spinach (Spinacia oleracea) Pc in close proximity to spinach PSI and cyt b6f, in both the thylakoid vesicle–embedded and solubilized states. We demonstrated that the hydrophobic patch residues of Pc are in close proximity to PSI and cyt b6f, whereas the acidic patch residues of Pc do not form stable salt bridges with either PSI or cyt b6f, in the electron transfer complexes. The transient characteristics of the interactions on the acidic patch facilitate the rapid association and dissociation of Pc. 相似文献
188.
Dissociated yolk sac cells from quail embryos at the definitive primitive streak stage were reaggregated, using a gyratory shaker with or without dimethyl sulfoxide (DMSO). After 24 h of incubation in the shaker, the aggregates were transferred onto a whole egg agar medium containing 59Fe, and incubation was continued for an additional 48 h. It was clearly shown that DMSO-treated yolk sac aggregates showed a higher incorporation of radioactive iron into heme than the control culture without DMSO. The maximal stimulatory effect was observed at around 0.75% DMSO. 相似文献
189.
Digestion is an important process in understanding the feeding ecology of animals. We examined digesta passage time, digestibility,
and total gut fill in Japanese macaques (Macaca fuscata; n = 4) under 4 dietary conditions representing the seasonal and regional variations in the diets of wild populations to determine
the effects of food type and food intake on these digestive features. Food type is associated with mean retention time (MRT),
digestibility, and total gut fill. Dry matter intake (DMI) of food correlates positively with total gut fill but not with
MRT or digestibility. Conversely, indigestible DMI affected MRT negatively. Thus, when Japanese macaques consume high-fiber
foods, MRT becomes shorter and digestibility is lower than when eating low-fiber foods. Moreover, macaques experience increases
in total gut fill when they consume high-fiber diets or a large amount of food. Japanese macaques may excrete difficult-to-digest
food components quickly; they nevertheless buffer an increase in food intake by an increase in gut fill. Our study offers
new insights into the relationship between feeding ecology and nutritional physiology in primates by simultaneously examining
the effects of food type and intake level on MRT and digestibility. 相似文献
190.
Nishijima T Komatsu H Gatanaga H Aoki T Watanabe K Kinai E Honda H Tanuma J Yazaki H Tsukada K Honda M Teruya K Kikuchi Y Oka S 《PloS one》2011,6(7):e22661