• Korean Journal of Veterinary Research
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• v.27 no.1
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• pp.27-34
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• 1987

To verify the direct effects of the thyroid hormone ($T_3$) on the rabbit heart, $T_3$-Tyrode solution in vitro was perfused on the normal atrial muscles and enzymatically isolated ventricular myocytes of the rabbit. All the experimental procedures were conducted at $35^{\circ}C$ and the same procedures were repeated after Ca. 120 minutes from the beginning of $T_3$-Tyrode perfusion. Compared to the state between the normal Tyrode solution and $T_3$-Tyrode solution, results were observed on the same cells by electrophysiological methods (conventional intracellular recording and whole cell patch clamping) as soon as possible. The results obtained were as follows : 1. Action potential duration (APD) on the left atrial muscle was reduced under the perfusion of $T_3$-Tyrode. 2. Absolute refractory Period was shortened by $T_3$-Tryrode perfusion. (117 msec./114 msec., 90 msec./78 msec.) 3. Maximal Ca currents ($i_{Ca}$) were decreased in single: ventricular myocytes under the $T_3$-Tyrode (2.98 nA) than under the normal Tyrode (6.65 nA) 4. On I-V relation, reversal potential was shifted to lower membrane potential and membrane potential showing maximal $i_{Ca}$was lowered from +10mV to -20mV by $T_3$ effect. 5. Above results were likely to explain that tachycardia in the hyperthyroid state was caused in part by the reduced repolarization phase and the reduced refractory period due to the decrease of the Ca current.

• Journal of Nutrition and Health
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• v.28 no.10
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• pp.1004-1014
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• 1995

Effect of age and dietary fatty acid composition on immune responses were investigated in Sprague-Dawley male rets. The animals weighing 88.6$\pm$2.2g were fed 10% dietary fat (W/W, 20% of calorie) with P/S ratio of 0.5, 1 and 2, and in each group, there were three different levels of n-6/n-3 fatty acid ratio; 2, 4 and 8(3$\times$3). The experimental periods were 1 month, 6 months and 12 months. The results of this study were; 1) Weights of thymus and spleen were significantly reduced with increasing age, moreover thymus weights were reduced with increasing the degree of unsaturation in dietarty fatty acid at 12 month. 2) The proportion of splenic lymphocyte in the total T-cell was increased with increased with age. The proportion of helper T-cell was not changed, while the proportion of suppressor T-cell was decreased. Thus at 12 month, the ratio of helpe $r^pressor T-cell was appeared to increase significantly, and showed the tendency to increase by consuming the low amount of dieraty n-3 fatty acid. 3) Proliferation stimulated by Con A or PWM reduced significantly at 12 month in which are high in dietary P/S ratio, representing the similar pattern with decrease in thymus weight. 4) Natural killer cell activities were shown significantly higher at 1 month than those at 6 month or 12 month.th.

• Preventive Nutrition and Food Science
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• v.11 no.1
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• pp.1-5
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• 2006

Conjugated linoleic acid (CLA) is a group of positional and geometric isomers of linoleic acid that have been used to reduce the incidence, growth and metastasis of breast, colon, prostate and gastric cancer in animals. CLA could reduce tumor growth by altering angiogenesis; a process requiring associated angiogenic factors such as vascular endothelial growth factor (VEGF). In this study, we determined whether CLA could modulate the expression of VEGF in murine mammary tumor cells and adipocytes. The c9, t11-CLA isomer reduced VEGF transcripts and protein when mammary tumor cells were stimulated with PMA. That isomer also reduced VEGF expression in un stimulated mouse 3T3-L1 adipocytes. Since VEGF can be regulated by cyclooxygenase-2 (COX-2), we determined whether CLA could alter COX-2 enzyme expression and $PGE_2$ production. The c9, t11-CLA isomer reduced not only COX-2 enzyme expression but also $PGE_2$ production. Thus, c9, t11-CLA could modulate neovascularization by alteration of VEGF expression from mammary tumor cells and adipocytes by reducing COX-2 metabolites.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.557-562
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• 2006

Hypoxia induced angiogenesis and inflammation are essential processes for metastasis and progress of solid tumors. We examined the anti-angiogenic and inflammation related activity of Kochiae Fructus (KF) extract. To investigate the roles of the KF extract, we performed MTS assay, western blots using HaCaT cells and $HepG_2$ cells. The results are as follows. The protein level of $HIF-1{\alpha}$ was reduced when induced by $CoCl_2$ in $HepG_2$ cells treated with KF extract and induced by IGF-11 in HaCaT cells treated with KF extract. KF extract reduced the mRNA level of VEGF in HaCaT cells and KF extract reduced the protein level of iNOS in HaCaT cells. These results suggest that KF extract contributes to the anti-angiogenic and anti-inflammatory activities and also we could assume that KF extract act as antioxidant or anti-inflammatory agents via reduction of $HIF-1{\alpha}$.

• Food Science of Animal Resources
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• v.36 no.1
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• pp.131-136
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• 2016

This study was conducted to investigate the effects of chicory fiber for the replacement of fat and smoking on quality characteristics of restructured sausages. Treatments were as follows; Control: Pork backfat 20%, T1: Pork backfat 10% + Chicory fiber 10%, T2: Control + Smoking, T3: T1 + Smoking. The addition of chicory fiber significantly reduced the moisture, fat, hardness and pH values, whereas the smoking treatment increased the fat, redness and pH values of restructured sausages (p<0.01). Additionally, interaction of them significantly affected the ash, chewiness and hardness values of restructured sausages. As a result, although the addition of chicory fiber decreased the quality characteristics of sausage, smoking treatment improved the reduced quality. Therefore, the chicory fiber and smoking treatment is helpful to develop restructured sausage products with reduced fat and compensated quality.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.466-471
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• 2002

Oxidative stress is considered to be associated with many diseases, such as inflammatory and cardiovascular diseases, aging and cancer. An important etiological mechanism of these diseases may be a causal relationship between the presence of oxidants and the generation of lipid hydroperoxides derived from enzymatic reactions or xenobiotic metabolism. The hydroperoxides can be decomposed to alkoxy- (ROㆍ) and peroxy- (ROOㆍ) free radicals that can oxidize other cell components, resulting in changes in enzyme activity or the generation of mediators, which can cause further cell damage. The aim of this study was to evaluate the ability of aqueous extract from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil (CK), to affect cellular response in primary cultures of rat hepatocytes to t-butyl hydroperoxide (t-BHP) induced oxidative stress and hepatotoxicity. CK-treated cells showed an increased resistance to oxidative challenge, as revealed by a higher percent of survival capacity in respect to control cells. CK reduced t-BHP-enhanced lipid peroxidation measured as production of malondialdehyde and enhanced intracellular reduced glutathione depletion by t-BHP. Furthermore, CK protected from the t-BHP-induced intracellular generation of reactive oxygen species assessed by monitoring dichlorodihydrofluorescein fluorescence. It can be concluded that CK exerts an antioxidant action inside the cell, responsible for the observed modulation of the cellular response to oxidative challenge, and CK have a marked antioxidative and hepatoprotective potency.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.157-160
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• 1998

To find out the effects of humidification and hardening of rice (Oryza sativa L. cv. Ilpumbyeo) seeds on the germination, both normal and artificially aged seeds with 60% germination rate were humidified at 40, 60, and 80% RHs and $25^{\circ}C$ for five weeks or hydrated for 6, 12, 18, and 24 hours at $25^{\circ}C$ from one to five cycles for hardening. Relative humidity and duration of humidification did not affect the germination rate of normal seeds, while reduced the time to get 50% germination rate ($T_{50}$) by 1.0～1.6 days compared to that of normal seeds at $25^{\circ}C$. Aged seeds humidified at 40 and 60% RHs did not affect the germination rate and $T_{50}$ regardless of relative humidity and duration of treatment, while at 80% RH, the germination rate decreased and $T_{50}$ increased significantly with the duration of humidification. Hardening of normal seeds reduced $T_{50}$ by 0.7～1.1 days without changes in the germination rate. However, the germination rate and $T_{50}$ of aged seeds soaked in water for 6, 12, and 18 hours were similar regardless of soaking/drying cycles, while hardening of artificially aged seeds with 1～4 cycles in 24 hours soaking increased the germination rate by 11-16% and reduced $T_{50}$ by 1.4～2.0 days.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.757-761
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• 2010

This study was conducted to assess the effects of organic and inorganic copper on performance in growing pigs. A total of 100 pigs, average age 63 d and initial body weight 21.46${\pm}$1.13 kg, were assigned to five treatment groups. Dietary treatments included i) CON (basal diet, 0 ppm Cu), ii) T1 (basal diet with 67 ppm Cu as cupric sulfate, $CuSO_4$), iii) T2 (basal diet with 134 ppm Cu as $CuSO_4$), iv) T3 (basal diet with 67 ppm Cu as cupric methionate, CuMet) and v) T4 (basal diet with 134 ppm Cu as CuMet). Throughout the entire experimental period, ADG (average daily gain), ADFI (average daily feed intake) and G/F (gain: feed) ratios showed no significant differences. The dry matter digestibility was improved in the T1, T2, T3, and T4 treatments (p<0.05), as compared with CON. Nitrogen digestibility was improved in the T3 treatment group as compared with CON (p<0.05). As compared with the T1 treatment group, fecal pH values were improved in the CON, T3, and T4 treatment groups (p<0.05). Fecal Cu concentrations were significantly lower in the CON, T3, and T4 treatment groups than in T1 and T2 (p<0.05). The incidence of diarrhea was reduced when the pigs were fed on the T2, T3, and T4 diets as compared with CON. In conclusion, diets supplemented with 67 or 134 ppm Cu as CuMet may prove effective in improving nutrient digestibility and fecal pH value in growing pigs, and fecal Cu concentrations may be reduced by CuMet supplementation.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.331-336
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• 1998

A systematic design method for PDC(Parallel Distributed Compensation)-type continuous time Takagi-Sugeno(T-S in short) fuzzy control systems which have inaccessible states is developed in this paper. Reduced-dimensional fuzzy state estimator is introduced from existing T-S fuzzy model using the PDC structure of Wang et al. [1] LMI(Linear Matrix Inequalities) problems which represent the stabililty of the reduced-dimensional fuzzy state estimator are derived. Pole placement constraints idea for each rules is adopted to determine the estimator gains and they are also revealed as LMI problems. these LMI problems are combined with Joh et al's [7][8] LMI problems for PDC -type continuous time T-S fuzzy controller design to yield a systematic design method for PDC -type continuous time T-S fuzzy control systems which have inaccessible states.

• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.16-20
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• 2003

Nitrogen(N) and phosphorus(P) in surface streams mainly lead to euthrophication. It aggravates water quality and consequently increases the purification costs. As a resolution of water contamination caused by household drainage through irrigation route by 70% of the 1,300 community residents in Eum-Am Myun, Seo-San city, was implemented biological self-purification method by growing Oenanthe Javanica along the polluted water tunnel. The contaminated water was efficiently purified after passing the dropwort field; DO conc. of effluent water was increased 8.3∼61.9% after through the drop wort field. HRT of experiment system was changed 0.05∼1.50/day. 50% of BOD was eliminated at the range above 12 mg/l of Influent BOD conc. Also, 50% of COD was eliminated at the range above 30 mg/l of Influent COD conc. Finnally, the influent T-N loading at range below 1.5 g/m$^3$/d reduced 50% of Influent T-N conc., and so did influent T-P loading at the range below 0.03 g/m$^3$/dwas reduced 50% of Influent T-P conc.