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1.
Kuniyoshi Shimizu Shoko Fukunaga Keisuke Yoshikawa Ryuichiro Kondo 《Journal of Wood Science》2007,53(2):153-160
The effects of 120 methanol extracts prepared from bark and heartwood of 69 types of Japanese wood on the melanin production
of B16 melanoma cells were examined. The melanin content of B16 melanoma cells was determined spectrophotometrically at 405nm.
The extracts were also examined for their effects on cell viability. We found that the methanol extracts of Fagus crenata (buna, wood, 100μg/ml), Sapium sebiferum (Nankinhaze, wood, bark, 10μg/ml), and Zelkova serrata (keyaki, wood, 10μg/ml) greatly inhibited the melanin production of B16 melanoma cells without significant cytotoxicity.
However, these extracts did not inhibit tyrosinase activity at the concentration of 100μg/ml. These findings indicate that
the depigmenting mechanism of these extracts involves the suppression of some pigmenting signals in stimulating melanogenesis
rather than the inhibition of tyrosinase activity.
Part of this study was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, Japan, March 2003 相似文献
2.
1,4-Linked β-d-galactooligosaccharides with a degree of polymerization (DP) between 1 and 7 and 1,5-linked α-l-arabinooligosaccharides with a DP between 1 and 8 were labeled at their reducing ends with 2-aminobenzamide (2AB) in the presence of sodium cyanoborohydride. The 2AB-labeled oligosaccharides were shown to be homogeneous using high-performance anion-exchange chromatography (HPAEC) and by electrospray ionization mass spectrometry (ESI-MS). The signals in the 1H and 13C nuclear magnetic resonance (NMR) spectra of the 2AB-labeled oligosaccharides were then assigned using one- and two-dimensional NMR spectroscopy. These NMR data will be useful for the structural analysis of enzymatically synthesized galactan and arabinan side chains derived from rhamnogalacturonan I. 相似文献
3.
Yunting?FangEmail author Per?Gundersen Rolf?D.?Vogt Keisuke?Koba Fusheng?Chen Xi?Yun?Chen Muneoki?Yoh 《Journal of Forest Research》2011,16(5):341-350
Data have been compiled from published sources on nitrogen (N) fluxes in precipitation, throughfall, and leaching from 69
forest ecosystems at 50 sites throughout China, to examine at a national level: (1) N input in precipitation and throughfall,
(2) how precipitation N changes after the interaction with canopy, and (3) whether N leaching increases with increasing N
deposition and, if so, to what extent. The deposition of dissolved inorganic N (DIN) in precipitation ranged from 2.6 to 48.2 kg N ha−1 year−1, with an average of 16.6 kg N ha−1 year−1. Ammonium was the dominant form of N at most sites, accounting for, on average, 63% of total inorganic N deposition. Nitrate
accounted for the remaining 37%. On average, DIN fluxes increased through forest canopies, by 40% and 34% in broad-leaved
and coniferous forests, respectively. No significant difference in throughfall DIN inputs was found between the two forest
types. Overall, 22% of the throughfall DIN input was leached from forest ecosystems in China, which is lower than the 50–59%
observed for European forests. Simple calculations indicate that Chinese forests have great potential to absorb carbon dioxide
from the atmosphere, because of the large forest area and high N deposition. 相似文献
4.
Keisuke Tomioka Yuuri Hirooka Toshirou Nagai Hiroyuki Sawada Takayuki Aoki Toyozo Sato 《Journal of General Plant Pathology》2011,77(4):266-268
Severe blight of potted seedlings of monkshood caused by Plectosporium tabacinum was found in glasshouses in Kagawa Prefecture in southwest Japan in May 2001. Root rot and browning of stem bases were followed
by wilting and yellowing of leaves, then blighting of leaves, flower buds and stems. A fungus was isolated from diseased plants
and confirmed to cause the disease. The new disease was named “Plectosporium blight of monkshood”. 相似文献
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Pollen dispersal was estimated in two test plots in a hinoki (Chamaecyparis obtusa) seed orchard using a chloroplast DNA marker, the spacer region between thetrnD andtrnY genes, and SSCP (single strand conformation polymorphism). In Plot 1, 2,020 seeds from 40 trees within 30 m of the marker
tree were analyzed using the PCR-SSCP method. In Plot 2, 1,850 seeds from 37 trees were analyzed in the same manner. The results
revealed that the maximum pollen dispersal distance in the two plots exceeded 25 m. Pollen dispersal appeared to be inversely
proportional to the distance from the marker tree. The effective pollen dispersal was suggested to be less than about 20 m
in a mature hinoki seed orchard. Adjacent trees had an excessive influence when the pollen density was increased by artificial
flower stimulation. Therefore, it was suggested that seed production better resembles ideal random mating when carried out
as naturally as possible. In conclusion, the SSCP chloroplast DNA marker was a useful tool for amassing basic information
on pollen management in seed orchards of coniferous species. 相似文献
8.
Shigeya Maeda Hisao Kuroda Koshi Yoshida Kenji Tanaka 《Paddy and Water Environment》2017,15(2):263-276
A method for allocating allowable ranges of total nitrogen (TN) load to nonpoint (diffuse pollution) sources in a watershed has been developed by adopting the two-phase grey fuzzy optimization approach. Competing goals of water quality management authorities and TN load dischargers at nonpoint sources such as paddy field, upland crop field, and residential area are described with linear imprecise membership functions including interval numbers. TN load discharged from each cell of the nonpoint sources is assumed to be transported along with surface, subsurface, and river flow under the conventional first-order kinetic removal with respect to distance. The travel length of the load is estimated with a digital elevation model in a geographic information system (GIS). Uncertainty of river discharge and self-purification coefficients appearing in the TN transport model is also expressed with interval numbers. The GIS-aided grey fuzzy optimization model developed here is applied to the Seimei River watershed, Japan. By solving the optimization model, the allowable load represented by an interval number at each cell is procured, which would be a scientific base for effluent control regarding nonpoint sources in the area. 相似文献
9.
Victor Manuel Ocaño‐Higuera Alfonso Nivardo Maeda‐Martínez María Elena Lugo‐Sánchez Gillermina García‐Sánchez Enrique Márquez‐Ríos Silvia Gómez‐Jimenez Ramón Pacheco‐Aguilar 《Aquaculture Research》2011,42(8):1087-1095
Currently, there is an increasing interest in shipping live adult scallops to markets and broodstock to hatcheries; nevertheless, information about the shipping effect on live scallops physiology is very scarce. In a previous study, a method in emersion was developed to ship scallop seed out of water, but it was not known whether this method is useful to transport adult organisms. As a consequence, the purpose of this study was to evaluate the effects of transportation by the emersion method on the physiological status of the adductor muscle of adult giant lion's paw scallop. Live specimens were packaged in a container and transported in emersion for 11 h. Six scallops were frozen in a farm and a similar number were frozen as soon as they arrived to the laboratory. Physiological indices were determined in each lot and the survival was estimated 24 h after re‐immersion. As a result of the transportation, a significant loss (P<0.05) of total carbohydrates, glycogen, adenosine 5′‐triphosphate and adenilated energetic charge, and a significant increase (P<0.05) in the free amino acids concentration were observed. Eighty‐eight per cent survival was achieved; therefore, we conclude that this method is appropriate for shipping live adult scallops of Nodipecten subnodosus. 相似文献
10.
To evaluate windthrow resistance with respect to stem breakage, a nondestructive method for determining the shape of trunk
cross sections was developed. In this method, the coordinates of multiple gauge points set on the perimeter of a trunk are
calculated by measuring the distances between them. The shape between the gauge points is generated with the use of a profile
gauge placed between them. Measurement tests were conducted using profile gauges with lengths of 300 and 900 mm on model specimens
with four shape patterns and four different diameters. The accuracy of the estimation was verified by comparing the section
modulus calculated for the generated image and for the photograph. The average ratio of section modulus (generated/photo)
for all specimens was 0.994, which indicates that the proposed method is highly accurate. The section moduli of hollow trunks
can be evaluated using the profile method together with the drill resistance technique on the condition that 26% of the trunk
diameter could be drilled without skew. 相似文献