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991.
Heeson Chon Byungryul Choi Gajin Jeong Eungyo Lee Seunghui Lee 《Comparative immunology, microbiology and infectious diseases》2010,33(6):e41-e49
The objective of this study was to evaluate the immunomodulatory effects of specific bacterial metabolites of Lactobacillus plantarum 10hk2 to induce anti-inflammatory mediators in cell cultures of the murine macrophage cell line, RAW 264.7. The effects of the extracellular metabolites of this bacterial strain were examined by dividing them into protein and polysaccharide fractions. A specific protein fraction (8.7 kDa) was found to be a strong IL-10 inducer in LPS-stimulated RAW 264.7 cells and suppressed LPS-induced NF-κB induction and inhibited LPS-induced phosphorylation of I-κB and p38 MAPK. To the best of our knowledge, this was the first study that investigated the anti-inflammatory effects of an extracellular peptide derived from lactic acid bacteria. In addition, we characterized the inhibitory mode of this molecule in the induction of proinflammatory cytokines. Based on the findings presented in this study, this molecule holds promise for use as an agent to modulate inflammation related diseases. 相似文献
992.
Yong Duck Kim Ji Yun Min Mi Jin Jeong Hyun Jin Song Jung Gyu Hwang Chandrakant S. Karigar Gang Won Cheong Myung Suk Choi 《Journal of Wood Science》2010,56(5):411-417
A rapid and efficient colorimetric method based on the use of Fast Blue B-salt (FBB) was established to select catechin-rich
tea trees (Camellia sinensis L.). The catechin levels measured by the colorimetric method under optimized reaction conditions correlated closely with
estimations by high-performance liquid chromatography (HPLC) analysis. The FBB colorimetric method was successfully used to
classify 160 tea trees on the basis of their catechin contents into rich and poor lines. HPLC analysis of the FBB-selected
tea tree extracts showed them to contain (−)-epigallocatechin 186 mg/g in tea tree line HR-29, (−)-epicatechin 43.7 mg/g in
HR-82, (−)-epigallocatechin gallate 4.32 mg/g in HR-29, and (−)-epicatechin gallate 0.22 mg/g in HR-52. Classification of
tea trees from the Hadong region into catechin-rich and -poor trees was independent of the growing season. Thus the FBB colorimetric
method could find application as a reliable tool in screening and selection of tea trees on the basis of their catechin content. 相似文献
993.
Supersolidity, the appearance of zero-viscosity flow in solids, was first indicated in helium-4 torsional oscillator (TO) experiments. In this apparatus, the irrotationality of the superfluid component causes it to decouple from the underlying normal solid, leading to a reduction in the resonant period of the TO. However, the resonant period may be altered for reasons other than supersolidity, such as the temperature dependence of the elastic modulus of solid helium. Superimposing rotation onto oscillatory measurements may distinguish between supersolidity and classical effects. We performed such simultaneous measurements of the TO and the shear modulus, and observed substantial change in the resonant period with rotational speed where the modulus remained unchanged. This contrasting behavior suggests that the decrease in the TO period is a result of supersolidity. 相似文献
994.
Ji-Eun Kim Byung-Kee Baik Chul Soo Park Jae-Han Son Chang-Hyun Choi Youngjun Mo Tae-Il Park Chon-Sik Kang Seong-Woo Cho 《农业科学学报》2019,18(11):2652-2663
The purpose of this study is to identify major factors affecting the manufacture and quality of steamed bread, consumed in Southeast Asia including China, Japan, and Korea. Hence, flours of 11 Korean wheat cultivars were used to evaluate quality attributes of two different styles of steamed bread, Korean style steamed bread (KSSB) and northern-style Chinese steamed bread (NSCSB). KSSB prepared more ingredients and higher optimum water absorption of dough than NSCSB because Korean consumers prefer white and glossy surface and soft crumb. KSSB showed lower height, larger diameter and volume of steamed bread, higher stress relaxation, and softer texture of crumb than NSCSB. The correlation between flour characteristics and quality of steamed bread was different in KSSB and NSCSB. About 90% of variability in the height and volume of KSSB could be predicted from protein content, mixing tolerance of Mixograph, average particle size of flour, final viscosity and solvent retention capacity. Protein content and quality parameters also could explain the variation of steamed bread height in NSCSB. Korean wheat carrying Glu-A3c allele produced higher volume of steamed bread (704.7 mL) than Glu-A3d allele (645.8 mL) in KSSB, although there was no significant difference in volume of NSCSB by glutenin compositions. Glu-D1d and Glu-A3c alleles had softer texture of crumb than Glu-D1f and Glu-A3d alleles in KSSB, Glu-B3i allele also showed lower hardness of crumb than their counterpart allele in NSCSB. Hard wheat showed higher height and volume of steamed bread, and lower stress relaxation and hardness of crumb than soft wheat in KSSB. 相似文献
995.
Growth hormone (GH) is an essential polypeptide required for the normal growth and development of vertebrates. We have studied
the effects of light-emitting diodes (LEDs) emitting different spectra (red, green, and blue) on the GH of yellowtail clownfish
Amphiprion clarkii. Full-length GH cDNA from the pituitary of the yellowtail clownfish was first cloned and then the expression of GH mRNA under
different light spectra was measured. GH mRNA expression was significantly higher under green and blue light than under red
light spectra. These results indicate that in yellowtail clownfish, short-wavelength LED enhances growth more than long-wavelength
LED, and that LED lights are more effective for enhancing growth than white fluorescent bulbs. Injection of melatonin resulted
in significantly higher expression levels of GH mRNA compared to the control. We therefore conclude that green and blue light
enhance GH levels and that melatonin plays a role in modulating growth of the yellowtail clownfish. 相似文献
996.
Detailed knowledge of the reproductive characteristics of fish in tropical areas is currently lacking. We have performed a
histological study of the reproductive aspects of Sphaeramia orbicularis, a tropical fish found on the Weno Islands of the Chuuk Lagoon, Micronesia, and further estimated the gonadosomatic indices
(GSI) of this fish. The sex ratio was approximately 1:1. The standard length of males and females at 50% maturity was 49.0
and 46.9 mm, respectively. Histological observation of S. orbicularis ovaries and testes revealed that the fish exhibits multiple spawner characteristics, including coexistence of primary yolk
stages, migratory nucleus or mature stages, and asynchronism of the spermatogenesis process. Monthly variations in the GSI
and gonadal maturity stages demonstrated that reproductive activity occurs throughout the year. The findings in this study
provide important information on the spawning activity and season of S. orbicularis in Micronesia. 相似文献
997.
The grafted 3,5-dimethylphenyl group remarkably improved the low temperature flexibility of a polyurethane (PU) copolymer.
The rigid and blunt shape of 3,5-dimethylphenyl was designed to interrupt molecular interactions and to disturb the close
contact between PU chains and, thus, to improve the flexibility at extremely low temperature, while maintaining high and reproducible
tensile and shape memory properties at ambient temperature. The effect of the 3,5-dimethylphenyl group on the flexibility
of PU was tested at −30 °C together with a linear PU, and the reason for the exceptional flexibility at low temperature is
discussed. 相似文献
998.
The Korean 2008 self-sufficiency rate for grain was only 26.2%. Because of this, the quantity virtual water (VW) for crop product imports is much greater than that of other countries. International VW trade is especially important to Korea due to its dependency on foreign imports to maintain food security and to establish an agricultural water resource policy. Using international crop products trade statistics during 2003?C2007, this study analyzed the virtual water content (VWC) and international virtual water flow (VWF) of major crops. The national water savings and global water savings were also estimated. Major grain products, including 28 products made from 13 crops, were selected for the analysis, based on the net import and export of products totaling more than 10,000 tons. VWCs were computed for the selected major crop products using the VWC of the primary crop of Korea. International VWFs were estimated using the VWC of each crop products. The amount of imported VW was 16,804 and 226?M?m3 was exported, so that the net imported VW was 16,578?M?m3. VW import is concentrated in wheat, rice, maize (corn), and soybean crops. A small number of countries, including the USA, China, Brazil, etc., account for over 96% of the imported VW, indicating Korea??s heavy dependence on these countries. The average national water savings for Korea and the average global water savings according to crop were estimated using VW flow from international crop products trade during 2003?C2007. The estimate of national water savings was 23,870.3?M?m3. Three major crops, namely wheat, maize and soybean, account for 95.3% of this total VW saving. Global water savings from the VW trade amounted to 7,253.0?M?m3. Korea depends heavily on VW imports concentrated in specific crops and which are primarily imported from a particular set of countries. This indicates that Korea is vulnerable to disruptions in the international grain harvest such as those caused by natural disasters such as floods and drought. Any such disruption could easily become a critical issue for governmental planners who establish food and water supply policies for Korea. 相似文献
999.
Min Ho Jee Sung Ho Park Jin Uk Choi Young Gyu Jeong Doo Hyun Baik 《Fibers and Polymers》2012,13(4):443-449
A series of composite fibers composed of multi-walled carbon nanotube (MWCNT) and poly(vinyl alcohol) (PVA) are prepared by
varying co-flowing wet-spinning conditions such as spinning geometry and PVA concentration, which affect aligning shear stress
for MWCNTs during the wet-spinning. Then, structural features, mechanical and electrical performances of MWCNT/PVA composite
fibers are investigated as a function of the aligning shear stress of the wet-spinning process. SEM images of the composite
fibers exhibit that MWCNTs are wetted effectively with PVA chains. Polarized Raman spectra confirm that the alignment of MWCNTs
is enhanced along the composite fiber axis with increasing the aligning shear stress of the spinning process. Accordingly,
initial moduli and tensile strengths of the composite fibers are significantly increased with the increment of the aligning
shear stress. In addition, it is found that electrical conductivities of MWCNT/PVA composite fibers increase slightly with
the aligning shear stress, which is associated with the formation of efficient electrical conduction paths caused by well-aligned
MWCNTs along the composite fiber axis. 相似文献
1000.