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41.
Satomi Koretsune Kenji Fukuda Zhaoyang Chang Fuchen Shi Atsushi Ishida 《Journal of Forest Research》2009,14(2):88-94
We studied the importance of effective rainfall for interannual variation in water use efficiency (WUE) and tree-ring growth
of Chinese pine (Pinus tabulaeformis Carr.) and black locust (Robinia pseudoacacia L.) by examining correlations of seasonal precipitation with annual values of stable carbon isotope ratio (δ13C) and tree-ring width in early and late wood. The correlations with precipitation were examined for each month and for periods
of all possible lengths from 2 to 22 months starting from January of the previous year to October of the current year. The
period with the highest correlation was adopted as the most effective rainfall season for interannual variations in WUE and
tree-ring width. In early wood, precipitation during the dry season (October to May) before the growing season was negatively
correlated with δ13C in pine trees and positively correlated with ring width in pine and locust trees. In late wood, rainfall during the growing
season in the current year was negatively correlated with δ13C in pine and locust trees, and positively correlated with ring width in locust trees. Our results demonstrated the differences
in the water use strategies of pine and locust trees. The δ13C in pines indicated higher WUE and more conservative water use than in locust trees. Precipitation during the dry season
affected the interannual variation in WUE and tree-ring growth in pine and locust trees, indicating that rainfall during the
dry season is important for carbon gain and tree-ring growth during the following growing season. 相似文献
42.
A substance produced extracellularly by a marine bacterium, Pseudomonas C55a-2 strain, and possessing algal-killing activity against a diatom, Chaetoceros
ceratosporum, was isolated from the culture supernatant of the bacterium in order to identify its chemical structure. The algicidal substance
extracted with ethyl acetate from the culture supernatant was purified by using Sep-Pak treatment, reverse phase column chromatography
with Sephadex LH-20, and high performance liquid chromatography (HPLC) with Mightysil RP-18 GP. The purified substance was
identified as 2,3-indolinedione (isatin) (molecular weight 147) based on hydrogen-nuclear magnetic resonance (H-NMR) and gas
chromatograph-mass spectrometry (GC-MS) analysis. Among artificial synthetic compounds examined for algicidal activity against
Chaetoceros cells on the double-layer plates, 2,3-indolinedione (isatin) appeared the most effective and indoline showed relatively less
activity than isatin. 相似文献
43.
Satomi Ushizaka Kohji Sugie Masumi Yamada Mariko Kasahara Kenshi Kuma 《Fisheries Science》2008,74(5):1137-1145
The significance of Mn and Fe for the growth of a coastal marine diatom Thalassiosira weissflogii was investigated by performing culture experiments containing macronutrients with either Mn or Fe, or both. Only the addition
of both Mn and Fe induced the highest growth rates and maximal cell yields. Maximal growth was maintained in continuous culture
media, which were repeatedly prepared by an inoculation of pre-culture and the addition of both Mn and Fe to the control culture
medium containing macronutrients. In particular, it was found that the full growth recovery in Mn-sufficient medium (without
added Fe) is accomplished by the addition of Fe even after several days’ incubation. On the contrary, there was no sufficient
growth recovery by the addition of Mn after a long incubation time in Fe-sufficient medium but without additional Mn. These
results suggest that T. weissflogii in Mn-sufficient waters retains the ability for full physiological recovery for a long time, probably resulting from the
decrease in the oxidative stress of phytoplankton by the production of antioxidant enzyme Mn superoxide dismutase during a
long incubation period. 相似文献
44.
Masataka Satomi Kei-ichi Shozen Ayumi Furutani Youhei Fukui Meiko Kimura Motoshige Yasuike Yasuhiro Funatsu Yutaka Yano 《Fisheries Science》2014,80(4):849-858
In order to elucidate mechanisms of tyramine accumulation during fish sauce production, two tyramine-producing bacterial strains, referred to as TyrA and TyrB, were isolated from fish sauce mash accumulating over 141 mg of tyramine per 100 g of sample. Both strains were identified as Tetragenococcus halophilus based on phenotypic characterization and a 16S rRNA gene sequence analysis. Molecular analysis of the tyramine-producing gene in the two strains confirmed the presence of a ~30-kb plasmid encoding a single copy of the pyridoxal phosphate-dependent tyrosine decarboxylase gene (tdcA) along with three other genes related to tyramine synthesis (tdc cluster). The complete nucleotide sequences of plasmids extracted from the two strains indicated that both plasmids were almost identical, except for a 1.6-kb transposon sequence in the plasmid from the strain TyrB. Both plasmids had a replication region, a plasmid maintenance region, and two putative mobile genetic elements located upstream and downstream of the tdc cluster. This structure was identical to that of tetragenococcal plasmids encoding histidine decarboxylase (hdcA), which were sequenced previously. These results suggest a common origin for plasmids encoding hdcA and tdcA. In addition, the genes for both these biogenic amines are distributed among tetragenococcal species via this plasmid. 相似文献
45.
Yano S Fujimura Y Umeda D Miyase T Yamada K Tachibana H 《Journal of agricultural and food chemistry》2007,55(17):7144-7148
It was previously reported that (-)-epigallocatechin-3-O-gallate (EGCG) suppresses the expression of the high-affinity IgE receptor FcepsilonRI in human basophilic cells and that this suppressive effect is associated with EGCG binding to the cell surface. This study examined the effects of five methylated derivatives of EGCG, (-)-epigallocatechin-3-O-(3-O-methyl)gallate (EGCG 3' 'Me), (-)-epigallocatechin-3-O-(4-O-methyl)gallate (EGCG 4' 'Me), (-)-4'-O-methyl-epigallocatechin-3-O-gallate (EGCG 4'Me), (-)-epigallocatechin-3-O-(3,4-O-methyl)gallate (EGCG 3' '4' 'diMe), and (-)-4'-O-methyl-epigallocatechin-3-O-(4-O-methyl)gallate (EGCG 4'4' 'diMe) on FcepsilonRI expression and ERK1/2 phosphorylation, and each of their cell surface binding activities was measured. Of these five methylated derivatives, three that are methylated at the 3' '- and/or 4' '-position, EGCG 3' 'Me, EGCG 4' 'Me, and EGCG 3' '4' 'diMe, suppressed FcepsilonRI expression and ERK1/2 phosphorylation, although the suppressive effects were lower than that of EGCG. EGCG 4'Me and EGCG 4'4' 'diMe, both of which are methylated at the 4'-position, did not demonstrate a suppressive effect. Furthermore, it was found that EGCG 3' 'Me, EGCG 4' 'Me, EGCG 3' '4' 'diMe, and EGCG 4'Me, which are methylated at the 3' '- and/or 4' '-positions or the 4'-position, could bind to the cell surface even though their binding activities were lower than that of EGCG. Only EGCG 4'4' 'diMe, which is methylated at both the 4'- and 4' '-positions, could not bind. These results suggest that the trihydroxyl structure of the B ring is essential for EGCG to exert the suppressive effects and that the hydroxyl groups on both the 4'-position in the B ring and the 4' '-position in the gallate are crucial for the cell surface binding activity of EGCG. 相似文献
46.
Satomi ISHII Nobuo SUZUI Sayuri ITO Noriko S. ISHIOKA Naoki KAWACHI Norikuni OHTAKE Takuji OHYAMA Shu FUJIMAKI 《Soil Science and Plant Nutrition》2009,55(5):660-666
Real-time images of nitrogen fixation in an intact nodule of hydroponically cultured soybean ( Glycine max [L] Merr.) were obtained. In the present study, we developed a rapid method to produce and purify 13 N-labeled radioactive nitrogen gas (half life: 9.97 min). 13 N was produced from a 16 O (p, α) 13 N nuclear reaction. The target chamber was filled with CO2 and irradiated for 10 min with protons at an energy of 18.3 MeV and an electric current of 5 μA, which was delivered from a cyclotron. All CO2 in the collected gas was absorbed and removed with powdered soda-lime in a syringe and replaced with helium gas. The resulting gas was injected into gas chromatography and separated and a 35 mL fraction, including the peak of [13 N]-nitrogen gas, was collected by monitoring the chromatogram. The obtained gas was mixed with 10 mL of O2 and 5 mL of N2 and used in the tracer experiment. The tracer gas was fed into the underground part of intact nodulated soybean plants and serial images of the distribution of 13 N were obtained non-invasively using a positron-emitting tracer imaging system (PETIS). The rates of nitrogen fixation of the six test plants were estimated to be 0.17 ± 0.10 μmol N2 h−1 from the PETIS image data. The decreasing rates of assimilated nitrogen were also estimated to be 0.012 ± 0.011 μmol N2 h−1 . In conclusion, we successfully observed nitrogen fixation in soybean plants with nodules non-invasively and quantitatively using [13 N]N2 and PETIS. 相似文献
47.
Toshiyuki Usami Satomi Morii Chizumi Matsubara Yoshimiki Amemiya 《Journal of General Plant Pathology》2012,78(5):368-371
Rot diseases of hydroponically cultured leaf lettuce, coriander, and chervil were found in Chiba Prefecture, Japan. Stems and petioles of the three diseased plants became brown or black with a soft rot, and vascular parts of the stems became discolored. Seemingly similar fungi were isolated from the diseased plants. Pathogenicity of these fungal isolates to each plant was demonstrated by inoculation tests. The fungi were identified as Plectosphaerella pauciseptata based on morphological and cultural characters. This identification was supported by phylogenetic analysis with rDNA ITS1-5.8S-ITS2 regions. The diseases were named Plectosphaerella rot (Plectosphaerella huhai-byo in Japanese) of lettuce, coriander, and chervil. 相似文献
48.
In-Sun Park Momoko Koiso Satomi Morimoto Takafumi Kubo Hyun-O Jin Ryo Funada 《Journal of Wood Science》2012,58(1):64-68
We attempted to develop a method for the regeneration of plantlets from mature seeds of medically important Magnolia obovata via the induction of somatic embryogenesis in vitro. We initially cultured halves of mature seeds on either Murashige and
Skoog (MS) medium or B5 medium that contained 0, 1, 5 or 10 μM gibberellic acid (GA3) for 1 month and then transferred the half-seeds to half-strength MS basal medium or B5 basal medium for further culture in the absence of GA3. Proembryogenic masses (PEMs) were observed 1 month after the transfer of the halved mature seeds to the medium without GA3. The frequency of formation of PEMs was higher (28%) after initial culture in MS basal medium plus 1 μM GA3 than in other tested media (0 or 4%). Somatic embryos that had been developed from PEMs were cultured on half-strength MS
basal medium or B5 basal medium for completion of maturation and then transferred to fresh aliquots of the same medium for initiation of germination.
The frequency of germination, with the formation of normal primary leaves and roots, was above 80%. We transferred the somatic
embryo-derived plantlets to soil for acclimatization and the plantlets continued to thrive. 相似文献
49.
Mao Mizukawa Hiroko Sato Satomi Nishikawa Akane Kashimura Hironobu Nishina Tetsuya Sakairi 《Journal of toxicologic pathology》2021,34(1):123
This paper describes the spontaneous ovarian choriocarcinoma observed in a young female Crl:CD1 (ICR) mouse. The mouse was sacrificed at 8 weeks of age after oral administration of a compound for 2 weeks. The left ovary was found to be cystically enlarged with dark red hemorrhaging. The cystic mass contained abundant blood plasma and erythrocytes. At the peripheral regions of the mass, large pleomorphic tumor cells with bizarre shaped nuclei were detected. Tumor cells contained a single large nucleus and abundant eosinophilic to amphophilic cytoplasm. Histopathology of the tumor cells resembled that of trophoblastic giant cells. Therefore, the observed ovarian lesion was diagnosed as a choriocarcinoma. No microscopic lesions were observed in the right ovary or other reproductive organs. Ovarian choriocarcinoma was considered to be of non-gestational origin. This is the first report of ovarian choriocarcinoma in a young ICR mouse. 相似文献
50.
We examined the effect of flavones on the expression of the high-affinity IgE receptor FcepsilonRI, which plays a central role in the IgE-mediated allergic response. Flow cytometric analysis showed that the flavones chrysin and apigenin were able to reduce the cell surface expression of FcepsilonRI in human basophilic KU812 cells. Immunoblot analysis revealed that the total cellular expression of the FcepsilonRI alpha and gamma chains decreased upon treatment with chrysin and apigenin. Moreover, the level of mRNA expression of the FcepsilonRI alpha and gamma chains also decreased when the cells were cultured with the two flavones. Previously, we demonstrated that the reduction of extracellular signal-regulated kinase1/2 (ERK1/2) phosphorylation was involved in the downregulation of FcepsilonRI expression. The two flavones were shown to reduce the level of ERK1/2 phosphorylation. These results suggested that chrysin and apigenin have the ability to downregulate FcepsilonRI expression and this suppressive effect may be due to the reduction of ERK1/2 phosphorylation. 相似文献