• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.131-155
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• 1983

Though it has been widely known the nitrogen effects are influenced by soils, varieties, and mineral nutrients in the rice culture, few analyses in relation to the factors increasing nitrogen effect have been studied in Korea. The effects of potassium and silica on the factors increasing nitrogen effects in paddy soils were investigated in accordance with soil improvement practices and nitrogen application methods for the cultivated varieties. The results obtained are as follows. 1. For 413 paddy fields, the yield from soils without nitrogen application ranged from 200 to 850kg/10a and that from nitrogen application did 350 to 1,051kg/10a. The yield increament by nitrogen application varied 50 to 650kg/10a depending on soils. 2. Soil chemical characteristics for high yield were different between with nitrogen and without nitrogen application. In the without nitrogen application, however, contents of organic matter, phosphorous, potassium and calcium of high yield soils were lower than those of low yield, while the available silica content was higher in the former. 3. The yield increased with nitrogen application up to 22.4kg/10a and thereafter it decreased. These phenomena were supposed to be not be decrease of nitrogen uptake but by lowered silica uptake. 4. Clay soil incorporation, deep plough, and inorganic constituents control such as Ca, Mg, and $Sio_2$ were effective as soil improvement praitices. It was appeared that increases of silica content and Ca/Mg ratio were important to increase nitrogen effects. 5. For the correlation between yield and yield components, it was high between yield and panicle in low nitrogen level and so was it between grain yield and ripening rate in high nitrogen. 6. In the urea and super granule urea application plot, recovery rate of nitrogen by plant and soil was high and yield was remarkable high. 7. Regardless of fertilizer types such as ammonium sulfate and urea, the residual nitrogen was about 4kg/10a in both plots of 5.8 and 11.6kg/10a. N applied. 8. The potassium application to soil enhanced the nitrogen efficiency. It was more effective in low potassium soil. 9. Optimum pH value for gel formation in the 4% sodium silicate solution was approximately 6.6. 10. It was suggested that silica could affect to rice plant growth as the inorganic and organic chemical components.

• Journal of Chest Surgery
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• v.36 no.12
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• pp.887-893
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• 2003

External stimuli increases intracellular (IC) $Ca^{2+}$, which increases extracellular (EC) $K^{+}$. To verify $K^{+}$ effects on the vascular contraction, we performed an experiment using mouse aortic endothelial cell. Meterial and Method: We examined the mouse aortic contractility changes as we measured the IC $Ca^{2+}$ change and ionic current by using the voltage clamp technique under different conditions such as: increasing EC $K^{+}$, removing endothelial cell, giving L-NAME (N-nitro-L-arginine methyl ester) which suppress nitric oxide formation, Ouabain which control N $a^{+}$ - $K^{+}$ pump and N $i^{2+}$ which repress N $a^{+}$-C $a^{2+}$ exchanger Result: When we increased EC $K^{+}$ from 6 to 12 mM, there was no change in aortic contractility. Aorta contracted with more than 12 mM of EC $K^{+}$. Ace-tylcholine (ACh) induced relaxation was inhibited with EC $K^{+}$ from 6 to 12 mM, but was not found after de-endothelialization or L-NAME treatment. ATP or ACh increased IC $Ca^{2+}$ in cultured endothelium. After maximal increase of IC $Ca^{2+}$, increasing EC $K^{+}$ from 6 to 12 mM made IC $Ca^{2+}$ decrease and re-decreasing EC $K^{+}$ to 6 mM made IC $Ca^{2+}$ increase. Ouabain and N $i^{2+}$ masked the inhibitory effect of endothelium dependent relaxation by increased EC $K^{+}$. Conclusion: These data indicate that increase in EC $K^{+}$ relaxes vascular smooth muscle and reduces $Ca^{2+}$ in the endothelial cells which inhibit endothelium dependent relaxation. This inhibitory mechanism may be due to the activation of N $a^{+}$- $K^{+}$ pump and N $a^{+}$-C $a^{2+}$ exchanger. $a^{+}$-C $a^{2+}$ exchanger.r.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1790-1799
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• 2010

A controlled and double blinded trial was performed to evaluate the effects of OPE supplementation on blood circulation in healthy male smokers. The study population consisted of 92 healthy male smokers aged $44.4{\pm}7.8$ years. The supplement group (n=49) received OPE containing 100 mg quercetin/day for 10 weeks, while the control group (n=43) received placebo powders. The prothrombin time and activated partial thromboplastin time increased significantly after OPE consumption, indicating the attenuated blood clot formation by OPE. In conclusion, these results indicate that the daily consumption of OPE (containing 100 mg quercetin) for 10 weeks exerts significant health benefits through the modulation of physiological functions including the blood circulation in male smokers.

• Journal of the Korean Wood Science and Technology
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• v.13 no.2
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• pp.14-34
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• 1985

One of the techniques for altering the properties of wood that has received considerable attention in the last twenty years is the formation of a wood-polymer composite (WPC) by irradiation and heat-catalyst polymerization of a monomer incorporated into the wood matrix. Wood-polymer composites are the new products having the superior mechanical and physical properties and the combinated characteristics of wood and plastic. The purpose of this experiment was to obtain the basic data for the improvement of wooden materials by manufacturing WPC and Staypak. The species examined was Hyunsasi-Namoo (Populus alba ${\times}$ P. glandulosa) which had not been utilized yet. Methylmethacrylate (MMA) as monomer, benzoyl peroxide (BPO) as initiator and methyl alcohol as bulking agent were used. The monomer containing BPO was impregnated into wood pieces by the dipping and the vacuum process for 2 hours. After impregnation, the treated samples were polymerized on the hot press with pressure and heat-catalyst methods. The results obtained were summarized as follows 1. The monomer loading into wood by the dipping process was 12.13 percent and 29.99 percent by the vacuum. The polymer loading into wood by the dipping process was 6.79 percent and 15.44 percent by the vacuum. 2. Comparing with Staypak, antishrink efficiency (ASE) of WPC was 12.5 to 13.6 percent on the radial direction and 14.70 to 18.63 percent on the tangential. Antiswelling efficiency (AE) was 14.40 to 17.22 percent on the radial direction and 17.18 to 42.1 8 to 42.14 percent on the tangential. Reduction in water absorptivity (RWA) was 8.19 to 15.5 percent. As a whole, the vacuum process was better than the dipping. 3. The specific gravity of control, Staypak and WPC were 0.44, 0.66 and 0.61 to 0.62, respectively. 4. In the bending strength test, the strength in case that the load direction is on the radial surface was greater than that which the load direction is on the tangential. 5. Increasing rate of stress at proportional limit in compression perpendicular to grain was 72.26 percent in case of WPC by the dipping process, 78.93 percent by the vacuum and 99.09 percent in case of Staypak.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.224-229
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• 2010

This study was conducted to reclassify Cheongpung series based on the second edition of Soil Taxonomy, and to dicuss the formation of Cheongpung series distributed on the diluvial terrace. Morphological properties of typifying pedon of Cheongpung series were investigated, and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon of Cheongpung series has red (2.5YR 4/6) silty clay loam Ap horizon (0-18 cm), red (2.5YR 4/8) clay BAt horizon (18-35 cm), red (2.5YR 4/2) cobbly clay Bt1 horizon (35-65 cm), and red (2.5YR4/6) cobbly clay Bt2 horizon (more than 65 cm). The typifying pedon has an argillic horizon from adepth of 18 to more than 65 cm, and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. It can be classified as Ultisol, not as Alfisol. It has udic soil moisture regime, and can be classified as Udult. Also that meets the requirements of Typic Hapludults. It has 35% or more clay at the particle-size control section, and have mesic soil temperature regime. Therefore Cheongpung series can be classified as fine, mesic family of Typic Hapludults, not as fine, mesic family of Ultic Hapludalfs. Cheongpung series occur on moderately elevated diluvial terrace which have relatively stable geomorphic surface. They are developed as Ultisols with clay mineral weathering, translocation of clays to accumulate in an argillic horizon, and leaching of base-forming cations from the profile for relatively long periods under humid, and temperate climates in Korea.

• Journal of Chest Surgery
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• v.29 no.4
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• pp.373-380
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• 1996

Prevention of thromboembolism is the most important task in the development of bioconpatible small caliber artificial vascular graft. In normal vessels, vascular endothelial cells maintain homeosatsis by secreting numerous factors. The aim of this study is to develope a method which Improves biocompatibility of small caliver polyurethane graft using endothelial cell culture technique, and ev luate the efTectiveness of extracelluar matrix for endothelization which was produced by cultured fibroblast. Methods ; Multiporous polyurethane tube of 3 mm diameter, 0.3 mm thickness was manufactured for vascular graft. Three mongrel dogs were intubated and internal jugular veins removed. Extracelluar matrix produced by cultured flbrobast which was obtained from dog's internal jugular vein were coated to the polyurethane graft. Then, endothelial cells extracted from Jugular vein were cultured and fixed on the extracelluar matrix layer of vascular graft. Endothelial cell coated vascular grafts were implanted to the carotid arteries of experimental dogs as interposed autograft. Implanted grafts were removed after 3 and 6 weeks. As a control, PTFE graft was interposed on carotid artery. These experiments demonstrated that extracelluar matrix produced by fibroblast can afford a base for endothelial cell linings of polyurethane graft. Although thrombosis were developed on autografted en othelial cell coated graft, 33% opening was noticed, and showed less adhesion to adjacent tissue layer. These findings suggest that fiboblast produced extracelluar matrix which can be used for edothelial cell lining vascular graft, and by improving the cultured endothelial cell function, there will be a new modality for reducing thrombosis on small vascular graft.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.264-270
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• 2008

Phytic acid(PA) (Inositol hexaphosphate, $IP_6$) is a naturally occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plants and mammalian cells. Recently PA has received much attention for its role in anticancer activity. In the present study, the preventive effects of PA on colon carcinogenesis were investigated. Six-week old Fisher 344 male rats were fed a AIN-93G purified diet and PA(0.5% or 2% PA in water) for 8 weeks. The animals received two ($1^{st}\;and\;2^{nd}$ week) injections of azoxymethane(AOM, 15 mg/kg b.w.) to induce colonic aberrant crypt foci(ACF). After sacrifice, the total numbers of aberrant crypts(AC) and ACF in colonic mucosa were examined after staining with methylene blue. Blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. AOM induced the total numbers of $142.3{\pm}22.3$ ACF/colon and $336.6{\pm}55.1$ AC/colon. PA at the doses of 0.5 and 2% decreased the numbers of ACF and AC/colon in a dose-dependent manner. The numbers of ACF/colon and AC/colon by PA at the dose of 0.5% were $124.4{\pm}28.5\;and\;302.7{\pm}67.3$, respectively. PA at the dose of 2% significantly decreased the ACF and AC numbers to $109{\pm}18.1\;and\;254.8{\pm}50.6$, respectively(p<0.01). Especially, 2% PA significantly reduced the number of large ACF(${\geq}4$ AC/ACF) from $26.8{\pm}6.2$ ACF/colon to $15{\pm}6.7$ ACF/colon(p<0.01). Although some parameters in blood counts and serum chemistry were changed compared with the control, no specific toxicity was found. These findings suggest that phytic acid can be a chemopreventive agent for colon carcinogenesis resulting from inhibition of the development of ACF in the F344 rat.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.246-255
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• 1998

Ganoderan (GAN), an immunomodulating ${\beta}-glucan$ of G. lucidum, induces potent antitumor immunity in tumor-bearing mice. This study was set up to elucidate the ability of macrophage activation of GANs. GAN-treated Raw 264.7 macrophages showed enhanced production of nitric oxide (NO). The ability of GANs to produce NO was based on differences in chemical composition of GANs obtained from the mycelium on various carbon sources and mycelial fractionation. The highest NO production was observed in CW-AS-WS polysaccharide which was extracted from the mycelial wall. GAN-treated Raw 264.7 cells gave a 2-to 5-fold (24 hr) formation of NO levels compared with those treated with medium only. Partial removal of the protein in the extracellular GAN by TCA treatment did appreciably reduce its capacity to secrete NO. The mixture effect of GAN and LPS increased the nitric oxide secretion from RAW 264.7. The cell proliferation of GAN-treated Raw 264.7 cell tines inhibited as compared with its control. Of the culture supernatant of macrophage activated by GAN, the percentage of cytotoxicity against mouse leukemia L1210 cells was slightly dependent on the amount of NO in the culture supernatants of the activated-macrophages. These results indicate that the ${\beta}-glucan-related$ polysaccharides of the higher fungus activate macrophage and release nitric oxide. It also suggests that murine macrophages possess certain receptors for ${\beta}-anomeric$ glucans and play a critical role of ${\beta}-glucan-related$ tumor killing mechanism.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.1
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• pp.20-29
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• 2010

Naringin has antioxidant and antihyperlipidemic properties, however, phenolic compounds including naringin are unstable in the presence of light, heat and oxygen. Beta-cyclodextrin ($\beta$-CD) is a cyclic heptamer composed of seven glucose units that enhances the stability and solubility of molecules through the formation of inclusion complexes. This study was conducted out to compare the effects of CD-naringin (CD-N) inclusion complexes with naringin on lipid metabolism in high fat-fed animals. Male C57BL/6 mice were fed either CD-N (0.048%, w/w) or naringin (N, 0.02%, w/w) in a 20% high-fat (HFC, 15% lard, 5% corn oil, w/w) diet for 10 weeks. Orlistat (Xenical, 0.01%, w/w) was used as a positive control (PC). There were no differences in body weight, food intake, liver and heart weights, plasma triglyceride(TG), leptin, adiponectin, resistin, IL-$1{\beta}$ and IL-6 concentrations, and hepatic $\beta$-oxidation, carnitine palmitoyl transferase(CPT), glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme activities between the HFC and CD-N groups or between the HFC and N groups. However, both CD-naringin and naringin supplementation les to a significant reduction in the epididymal and perirenal white adipose tissue weights, plasma free fatty acid, insulin and blood glucose concentrations, hepatic cholesterol and TG contents and hepatic fatty acid synthase (FAS), phosphatidate phosphohydrolase (PAP) and HMG-CoA reductase activities compared to the HFC group. The plasma HDL-cholesterol concentration was significantly higher in CD-N and N groups than in HF and PC groups. These results indicate that both CD-naringin and naringin supplementation effectively improved plasma and hepatic lipid metabolism without differences between CD-N and naringin groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.605-611
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• 2012

Sea cucumber, $Stichopus$ $japonicus$, is used not only as an outstanding tonic food but also as a traditional medicine for the treatment of asthma, hypertension, rheumatism, anemia, and sinus congestion. The purpose of this study was to examine sea cucumber as an anti-gastritis and anti-gastric ulcer in HCl-ethanol-induced gastric and $H.$ $pylori$-infected animal models. Thirty 7-week-old SD rats and Mongolian gerbils were divided into normal (Nor, n=6), control (Con, 60% HCl-ethanol+water, n=6), groupI (DSCI, 60% HCl-ethanol+sea cucumber 30 mg/kg, n=6), groupII (DSCII, 60% HCl-ethanol+sea cucumber 100 mg/kg, n=6), and group III (DSCIII, 60% HCl-ethanol+sea cucumber 300 mg/kg, n=6). Sea cucumber significantly suppressed gastric lesions and ulcers in the 60% HCl-ethanol-induced gastric model. Especially, 100 mg/kg of sea cucumber showed significantly inhibitory effects. In histopathological analysis of the $H.$ $pylori$ model, we found that sea cucumber augmented the eradication rates of $H.$ $pylori$ and attenuated gastric ulcer formation. Our results suggest that sea cucumber has inhibitory effects on gastritis and gastric ulcers. In addition, sea cucumber can be applied for the treatment of $H.$ $pylori$.