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91.
Lee SU Lee JH Choi SH Lee JS Ohnisi-Kameyama M Kozukue N Levin CE Friedman M 《Journal of agricultural and food chemistry》2008,56(18):8541-8548
Onion plants synthesize flavonoids as protection against damage by UV radiation and by intracellular hydrogen peroxide. Because flavonoids also exhibit health-promoting effects in humans, a need exists to measure their content in onions and in processed onion products. To contribute to the knowledge about the levels of onion flavonoids, HPLC and LC-MS were used to measure levels of seven quercetin and isorhamnetin glucosides in four Korean commercial onion bulb varieties and their distribution within the onion, in scales of field-grown onions exposed to home processing or to fluorescent light and in 16 commercial dehydrated onion products sold in the United States. Small onions had higher flavonoid content per kilogram than large ones. There was a graduated decrease in the distribution of the flavonoids across an onion bulb from the first (outside) to the seventh (innermost) scale. Commercial, dehydrated onion products contained low amounts or no flavonoids. Losses of onion flavonoids subjected to "cooking" (in percent) ranged as follows: frying, 33; sauteing, 21; boiling, 14-20; steaming, 14; microwaving, 4; baking, 0. Exposure to fluorescent light for 24 and 48 h induced time-dependent increases in the flavonoid content. The results extend the knowledge about the distribution of flavonoids in fresh and processed onions. 相似文献
92.
93.
Lee WS Lee GJ Lee GJ Yeo CD Kang JS Kim YH Kim SJ Kim JS Hwang SY Park JS Hwang JW Kang KS Lee YS Jeon KS Um CH Hong SI Kim YS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1335-1338
Toxicogenomics is now emerging as one of the most important genomic application because the toxicity test based on gene expression profiles is expected to be more precise and efficient than current histopathological approaches in a pre-clinical phase. One of the challenging issues in toxicogenomics is the construction of intelligent database management system which can deal with heterogeneous and complex data from many different experimental and information sources. TEST(Toxicogenomics for Efficient Safety Test) database is especially focused on the connectivity of heterogeneous data and the intelligent query system which enable users to obtain relevant useful information from the complex data sets. The database deals with four kinds of information; compound, histopathology, gene expression, and annotation information. Currently, TEST database maintains toxicogenomics information for 16 compounds, 45 microarrays, 190 animal experiments, and customized 4.8 K rat clone set. Our presented system is expected to be a good information source for studying of toxicology mechanism in the genome-wide level and can also be applied to the designing toxicity test chip. 相似文献
94.
Effect of dihydrotestosterone on mouse embryonic stem cells exposed to H2O2-induced oxidative stress
Mi Na Lee Sang Hun Lee Min Young Lee Yun Hee Kim Jae Hong Park Jung Min Ryu Seung Pil Yun Yu Jin Lee Mi Ok Kim Kwangsung Park Ho Jae Han 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):247-256
Oxidative stresses induced by reactive oxygen species (ROS) have been shown to be involved in several physiological and pathophysiological processes, such as cell proliferation and differentiation. Steroid hormones can protect cells against apoptosis or induce cell proliferation by several mechanisms. Among androgenic hormones, dihydrotestosterone (DHT) is generated by a 5α-reduction of testosterone. Unlike testosterone, DHT cannot be aromatized to estradiol, therefore DHT is considered a pure androgenic steroid. This study was conducted to examine the effect of DHT (10-7 M) on H2O2 (10-3 M) -induced injuries in mouse embryonic stem (ES) cells. H2O2 induced ROS generation and increased lipid peroxide formation and DNA fragmentation. These effects of H2O2 were inhibited by pretreatment with DHT. H2O2 also increased the phosphorylation of p38 MAPK, SAPK/JNK and nuclear factor kappa B (NF-κB), but DHT blocked these effects. Moreover, H2O2 decreased DNA synthesis and the levels of cell cycle regulatory proteins [cyclin D1, cyclin E, cyclin-dependent kinase (CDK) 2, and CDK 4]. These effects of H2O2 were inhibited by pretreatment with DHT. In conclusion, DHT may partially prevent H2O2-induced cell injury through inhibition of ROS and ROS-induced activation of p38 MAPK, SAPK/JNK and NF-κB in mouse ES cells. 相似文献
95.
Seung Yub Shin Tae Hee Han Hyuk Joon Kwon Sun Joong Kim Pan Dong Ryu 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(3)
Very virulent infectious bursal disease virus (vvIBDV) causes high mortality in chickens but measures to reduce the mortality have not been explored. Chickens (8–9 weeks) were treated with 3 agents before and during vvIBDV inoculation. Dexamethasone treatment reduced the mortality of infected chickens (40.7% vs. 3.7%; p < 0.001), but treatment with aspirin or vitamin E plus selenium did not affect the mortality. The bursa of Fabricius appeared to have shrunk in both dead and surviving chickens (p < 0.01). The results indicate that dexamethasone can reduce mortality in vvIBDV-infected chickens and may provide therapeutic clues for saving individual birds infected by the virus. 相似文献
96.
Seung Woo Hu Hee Soo Myung Jong Seok Bae Eui Sang Yoo Seung Soon Im 《Fibers and Polymers》2000,1(2):76-82
A series of random copolyesters having various compositions were synthesized by bulk copolymerization of bishydroxyethyl terephthalate
(BHET) with 1,4-cyclohexane dimethanol (CHDM) or dimethyl isophthalate (DMI). CHDM and DMI content was less than 10 wt%. For
the synthesized copolyesters, isothermal crystallization rate, melting behavior, and equilibrium temperature were investigated
by calorimetry and by Avrami and Hoffman-Weeks equation. Crystalline lattice and morphology were studied by WAXD and SEM.
Regardless of the composition, the value of the Avrami exponent was about 3, which indicates that crystallization mechanism
of the copolyester was similar to those of PET homopolymer. Incoporation of CHDM or DMI units in PET backbone decreased the
crystallization rate of the copolyesters. Surface free energy of copolyesters was evaluated using the newly proposed equation.
The value of surface free energy was about 189×10−6 J2/m4 regardless of comonomer contents. This result is in good agreement with that of PET homopolymer. 相似文献
97.
Chol D. T. Abel Saroj K. Sharma Yona N. Malolo Sung Kyu Maeng Maria D. Kennedy Gary L. Amy 《Water, air, and soil pollution》2012,223(8):5205-5220
Soil aquifer treatment (SAT) is a cost-effective natural wastewater treatment and reuse technology. It is an environmentally friendly technology that does not require chemical usage and is applicable to both developing and developed countries. However, the presence of organic matter, nutrients, and pathogens poses a major health threat to the population exposed to partially treated wastewater or reclaimed water through SAT. Laboratory-based soil column and batch experiments simulating SAT were conducted to examine the influence of temperature variation and oxidation?Creduction (redox) conditions on removal of bulk organic matter, nutrients, and indicator microorganisms using primary effluent. While an average dissolved organic carbon (DOC) removal of 17.7?% was achieved in soil columns at 5?°C, removal at higher temperatures increased by 10?% increments with increase in temperature by 5?°C over the range of 15 to 25?°C. Furthermore, soil column and batch experiments conducted under different redox conditions revealed higher DOC removal in aerobic (oxic) experiments compared to anoxic experiments. Aerobic soil columns exhibited DOC removal 15?% higher than that achieved in the anoxic columns, while aerobic batch showed DOC removal 7.8?% higher than the corresponding anoxic batch experiments. Ammonium-nitrogen removal greater than 99?% was observed at 20 and 25?°C, while 89.7?% was removed at 15?°C, but the removal substantially decreased to 8.8?% at 5?°C. While ammonium-nitrogen was attenuated by 99.9?% in aerobic batch reactors carried out at room temperature, anoxic experiments under similar conditions revealed 12.1?% ammonium-nitrogen reduction, corresponding to increase in nitrate-nitrogen and decrease in sulfate concentration. 相似文献
98.
99.
Estimation of flood risk index considering the regional flood characteristics: a case of South Korea
Jung Younghun Shin Yongchul Jang Chun Hwa Kum Donghyuk Kim Young Sug Lim Kyoung Jae Kim Hyun Bae Park Tae Sun Lee Seung Oh 《Paddy and Water Environment》2014,12(1):41-49
Global warming is increasing the variability of climate change and intensifying hydrologic cycle components including precipitation, infiltration, evapotranspiration, and runoff. These changes increase the chance of more severe and frequent natural conditions, and limit ecosystem function and human activities. Adaptation to climate change requires assessment of the potential disaster risk. The objectives of this study were to estimate the flood risk index (FRI) considering regional flood characteristics at the national level and to prioritize the factors affecting flood risk through principal component analysis. FRI was estimated based on the Delphi survey results from 50 water resources experts in South Korea. The potential risk analysis was conducted for 229 local governments in South Korea. The results showed that natural and social factors were more influential flood risk factors to South Korea than administrative and economic and facility factors. Specifically, natural, social, administrative and economic, and facility factors were, respectively, highest at Jindo-Gun in Jennam-Do, Gumi-Si in Kyongsanbuk-Do, Dong-Gu in Incheon-Si, and Suwon-Si, Kyonggi-Do. Overall, the highest FRI is shown in Anyang-Si, Kyongggi-Do. The spatial distribution of the FRI was high in the southeastern coastal region and basins of the two biggest rivers in South Korea, and normalized flood frequency followed spatial patterns similar to FRIs. This study provided information on the relative flood risk index among administrative units for investment prioritization in flood risk management. In this regard, the suggested FRI is expected to significantly contribute to methodical and economic improvements in budget allocations for flood risk management. 相似文献
100.
Meredith A. Wilkes David Seung Gilles Levavasseur Richard M. Trethowan Les Copeland 《Cereal Chemistry》2010,87(2):95-99
An experiment was conducted using three related wheat (Triticum aestivum L.) genotypes grown on two different soil types (a grey vertosol and a red kandosol) using two different tillage practices (complete and zero) to test the effects of environmental influence on grain quality. Wheat grains from plants grown in each environment were milled into flour; protein and starch were analyzed. The soil type had the biggest impact on both protein and starch content, with the grains from the grey vertosol soil having higher total, insoluble, and soluble protein contents, and lower starch content and flour swelling values. When protein was analyzed using SDS‐PAGE, the major difference observed between grains from the two soil types was an increased intensity of polypeptide bands corresponding to β‐amylase in grains from plants grown on grey vertosol soils. 相似文献