• Journal of Chest Surgery
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• v.33 no.7
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• pp.531-540
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• 2000

Baclgrpimd; Recent studies have suggested that the cardioprotective effect of ischemic preconditioning(IP) is closely related to glycogen depletion and attenuation of intracellular acidosis. In the present study, the authors tested this hypothesis by perfusion isolated rabbit hearts with glucose(G) is closely related to glycogen depletion and attenuation of intracellular acidosis. In the present study, the authors tested this hypothesis by perfusion isolated rabbit hearts with glucose(G)-free perfusate. Material and Method; Hearts isolated from New Zealand white rabbits(1.5~2.0 kg body weight) were perfused with Tyrode solution by Langendorff technique. After stabilization of baseline hemodynamics, the hearts were subjected to 45 min global ischemia followed by 120 min reperfusion with IP(IP group, n=13) or without IP(ischemic control group, n=10). IP was induced by single episode of 5 min global ischemia and 10 min reperfusion. In the G-free preconditioned group(n=12), G depletion was induced by perfusionwith G-free Tyrode solution for 5 min and then perfused with G-containing Tyrode solution for 10 min; and 45 min ischemia and 120 min reperfusion. Left ventricular functionincluding developed pressure(LVDP), dP/dt, heart rate, left ventricular end-distolic pressure(LVEDP) and coronary flow (CF) were measured. Myocardial cytosolic and membrane PKC activities were measured by 32P-${\gamma}$-ATP incorporation into PKC-specific peptide and PKC isozymes were analyzed by Western blot with monoclonal antibodies. Infarct size was determined by staining with TTC(tetrazolium salt) and planimetry. Data were analyzed by one-way analysis of variance (ANOVA) and Turkey's post-hoc test. Result ; In comparison with the ischemic control group, IP significantly enhanced functional recovery of the left ventricle; in contrast, functional significantly enhanced functional recovery of the left ventricle; in contrast, functional recovery were not significantly different between the G-free preconditioned and the ischemic control groups. However, the infarct size was significantly reduced by IP or G-free preconditioning(39$\pm$2.7% in the ischemic control, 19$\pm$1.2% in the IP, and 15$\pm$3.9% in the G-free preconditioned, p<0.05). Membrane PKC activities were increased significantly after IP (119%), IP and 45 min ischemia(145%), G-free [recpmdotopmomg (150%), and G-free preconditioning and 45 min ischemia(127%); expression of membrane PKC isozymes, $\alpha$ and $\varepsilon$, tended to be increased after IP or G-free preconditioning. Conclusion; These results suggest that in isolated Langendorff-perfused rabbit heart model, G-free preconditioning (induced by single episode of 5 min G depletion and 10 min repletion) colud not improve post-ischemic contractile dysfunction(after 45-minute global ischemia); however, it has an infarct size-limiting effect.

• Proceedings of the Korean Geotechical Society Conference
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• 1991.10a
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• pp.87-102
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• 1991

It has been reported that the failure of Carsington Dam in Eng1and occured due to the existence of a thin yellow clay layer which was not identified during the design work, and due to pre-existing shears of the clay layer. The slope stability analyses during the design work, which utilized traditional circular arc type failure method and neglected the existence of the clay layer, showed a safety factor of 1.4. However, the post-failure analyses which utilized translational failure mode considering the clay layer and the pre-existing shear deformation revealed the reduction of safety factor to unity. The post-failure analysis assumed 10。 inclination of the horizontal forces onto each slice based on the results of finite element analyses. In this paper, Bishop's simplified method, Janbu method, and Morgenstern-Price method were used for the comparison of both circular and translational failure analysis methods. The effects of the pre-existing shears and subsquent movement were also considered by varying the soil strength parameters and the pore pressure ratio according to the given soi1 parameters. The results showed factor of safefy 1.387 by Bishop's simplified method(STABL) which assumed circular arc failure surface and disregarding yellow clay layer and pre-failure material properties. Also the results showed factor of safety 1.093 by Janbu method(STABL) and 0.969 by Morgenstern-Price method(MALE) which assumed wedge failure surface and considerd yellow clay layer using post failure material properties. In addition, dam behavior was simulated by Cam-Clay model FEM program. The effects of pore pressure changes with loading and consolidation, and strength reduction near or at failure were also considered based on properly assumed stress-strain relationship and pore pressure characteristics. The results showed that the failure was initiated at the yellow clay layer and propagated through other zones by showing that stress and displacement were concentrated at the yel1ow clay layer.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.161-171
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• 1999

Background: Interleukin-12 (IL-12) can induce antitumor effects in vivo. This antitumor effect is associated with T cell infiltration but the effect of IL-12 on the steps of T cell migration into the tumor tissue has not been fully elucidated. This study focused on the effect of IL-12 on the tumor growth and the metastasis and on the expression of E-selectin, an adhesion molecule which is activated endothelial specific in its expression. In addition, we studied whether the expression of E-selectin is associated with the TNF-$\alpha$, a cytokine that its production is increased by IL-12 and has functions inducing a variety of adhesion molecules. Methods: Mice of C57BL/6 strain were injected with Lewis lung cancer cells followed by either IL-12, TNF-$\alpha$, or normal saline by intraperitoneal route. Twenty eight days after tumor cell inoculation, metastatic nodules of lung were enumerated and immunohistochemical staining of the subcutaneous tumors were performed with monoclonal antibodies to CD4, CD8, CD16, and E-selectin. In IL-12 treated mice, the subcutaneously implanted Lewis lung tumors were decreased in size and the metastases were also decreased in number compared to control mice. On tumor tissues, increased infiltration of CD4+, CD8+, and CD16+ cells were oberved in IL-12 treated mice compared to control mice. In control mice, E-selectin was absent on tumor vessels, but the expression of E-selectin was increased on tumor vessels of IL-12 treated mice. Administration of TNF-$\alpha$ increased not only the expression of E-selectin but also infiltrations of CD4+, CD8+, and CD16+ cells on tumor tissues. Conclusions: These results demonstrate that IL-12 inhibits tumor growth and metastases through infiltrations of inflammatory cells in mouse model of Lewis lung carcinoma and E-selectin may playa role in inflammatory cell recruitment on tumor tissue following IL-12 administration. Also, TNF-$\alpha$ may have a role as a mediator responsible for the IL-12 induced expression of E-selectin.

• Food Science and Preservation
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• v.24 no.8
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• pp.1158-1167
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• 2017

In this study, ${\beta}$-1,3/1,6-glucan, lactic acid bacteria, and ${\beta}$-1,3/1,6-glucan+lactic acid bacteria were tested for 10 weeks using an immunodeficient animal model infected with LP-BM5 murine AIDS virus On the immune activity. Cytokines production, plasma immunoglobulin concentration, T cell and B cell proliferation were measured. As a result, the T cell proliferative capacity which was weakened by immunization with LP-BM5 murine AIDS virus increased significantly T cell proliferative capacity compared with the red ginseng control group. B cell proliferative capacity was significantly higher than the infected control group. Increased B cell proliferation was reduced. In the cytokine production, IL-2, IL-12 and IL-15 in the Th1-type cytokine increased the secretion of IL-2, IL-12 and IL-15 compared to the infected control. The proliferative capacity of the treated group was higher than that of the mixed treatment group. TNF-${\alpha}$ was significantly decreased compared with the infected control group. The IL-4, IL-6 and IL-10 levels were significantly inhibited in the infected control group and the Th1/Th2 type cytokine expression was regulated by immunohistochemistry. IgE, IgA, and IgG levels were significantly lower in the immunoglobulin secretion assay than in the control. As a result, the immunomodulatory effect of ${\beta}$-1,3/1,6-glucan+lactic acid bacteria was confirmed by mixing with LP-BM5 murine AIDS virus-infected immunodeficient animal model.

• The Journal of Internal Korean Medicine
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• v.33 no.4
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• pp.418-428
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• 2012

Objectives : Ojeok-san, a traditional herbal formula, has been used for the treatment of cold illness and its related symptoms such as headache, nausea and indigestion. This study was performed to compare effects of water (OJSW) and 70% ethanol extracts (OJSE) of Ojeok-san on inflammation and its related diseases atopy, asthma and obesity in vitro. Methods : We performed HPLC to investigate contents of index components of OJSW and OJSE. We investigated the effects of OJSW and OJSE with an in vitro model, using 5 cell lines, specifically RAW 264. 7, HaCaT, MC/9, BEAS-2B and 3T3-L1. Results : HPLC analysis displayed that the contents of index components were higher in OJSE than OJSW. In lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, OJSE significantly inhibited productions of interleukin (IL)-6, nitrite and prostaglandin $E_2$ ($PEG_2$). In TNF-${\alpha}$/IFN-${\gamma}$-treated HaCaT keratinocytes, OJSE significantly lowered levels of macrophage-derived chemokine (MDC) as well as regulated and normal T cell expressed and secreted (RANTES). OJSE also had a protective effect on inflammatory response by decreasing RANTES secretion in TNF-${\alpha}$-stimulated BEAS-2B cells. Conclusions : We conclude that OJSE could be more appropriate to enhance the biological activities against inflammation and its related diseases, and could be applied as a bioactive material for developing the potent anti-inflammatory agents.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.6
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• pp.283-290
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• 2013

A stoichiometric mixture of evaporating materials for $MgGa_2Se_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $MgGa_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $610^{\circ}C$ and $400^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by double crystal X-ray diffraction (DCXD). The temperature dependence of the energy band gap of the $MgGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.34 eV-(8.81{\times}10^{-4}eV/K)T^2/(T+251K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $MgGa_2Se_4$ have been estimated to be 190.6 meV and 118.8 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $MgGa_2Se_4$/GaAs epilayer. The three photocurrent peaks observed at 10 K are ascribed to the $A_{1^-}$, $B_{1^-}$exciton for n = 1 and $C_{27}-exciton$ peaks for n = 27.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.5
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• pp.217-224
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• 2008

A stoichiometric mixture of evaporating materials for $ZnIn_2Se_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $ZnIn_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $400^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $ZnIn_2Se_4$ single crystal thin films measured from Hall effect by van der Pauw method are $9.41\times10^{16}cm^{-3}$ and $292cm^2/v{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $ZnIn_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=1.8622eV-(5.23\times10^{-4}eV/K)T^2/(T+775.5K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $ZnIn_2Se_4$ have been estimated to be 182.7 meV and 42.6 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $ZnIn_2Se_4/GaAs$ epilayer. The three photo current peaks observed at 10 K are ascribed to the $A_{1}-$, $B_{1}-exciton$ for n = 1 and $C_{27}-exciton$ peaks for n = 27.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.167-173
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• 2016

This study investigated the effects of green tea polyphenol and vitamin C on type 2 diabetes mellitus by administering polyphenon 60 (P60) and sodium ascorbate (SA) to diabetic rats induced by high fat diet/low-dose streptozotocin. The experimental group was divided into five different groups: non-diabetic control group (NC), diabetes control group (DC), diabetes+P60 group (DM+P60), diabetes+SA group (DM+SA), and diabetes+P60+SA group (DM+P60+SA). P60 and SA were dissolved in 0.1% drinking water. After P60 and SA were administered for 16 weeks, fasting blood glucose, plasma insulin, serum triglyceride, blood urea nitrogen (BUN), and creatinine levels as well as kidney alkaline phosphatase (AP) and ${\gamma}$-glutamyltranspeptidase (GGT) activities were measured. Fasting blood glucose level increased 5-fold in the DC group compared to the NC group. In the DM+P60 group, fasting blood glucose level decreased by 14%. In the DM+P60+SA group, fasting blood glucose level decreased by 28% compared to the DC group, whereas the DM+SA group did not show any significant difference. The homeostasis model assessment for insulin resistance index increased in the DC group and decreased in the DM+P60+SA group compared to the DC group. Serum creatinine level increased in the DC group, but decreased by 17% in the DM+P60 group and by 43% in the DM+P60+SA group compared to the DC group. The serum BUN level increased in the DC group, but decreased by 41% in the DM+P60+SA group compared to the DC group. Kidney GGT and AP activities decreased in the DC group compared to the NC group; however, they were reversed by DM+P60+SA group. These results show that combined administration of both green tea polyphenol and vitamin C had better effects on improving blood glucose level, insulin resistance, serum triglyceride level, and protecting kidneys than administration of either green tea polyphenol or vitamin C alone in the context of type 2 diabetes.

• Journal of Sensor Science and Technology
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• v.11 no.5
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• pp.309-318
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• 2002

A stoichiometric mixture of evaporating materials for $CdIn_2S_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $CdIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $CdIn_2S_4$ single crystal thin films measured with Hall effect by van der Pauw method are $9.01{\times}10^{16}\;cm^{-3}$ and $219\;cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CdIn_2S_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.7116\;eV-(7.74{\times}10^{-4}\;eV)T^2/(T+434)$. The crystal field and the spin-orbit splitting energies for the valence band of the $CdIn_2S_4$ have been estimated to be 0.1291 eV and 0.0248 eV, respectively, by means of the photocurrent spectra and the Hopfield quasi cubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}5$ states of the valence band of the $AgInS_2$/GaAs epilayer. The three photocurrent peaks observed at 10K areascribed to the $A_1$-, $B_1$-, and C1-exciton peaks for n = 1.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.169-179
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• 2000

The purpose of this study is to develop the system which convert the optical difference of teeth texture between intact enamel and incipient caries lesion into shade difference by laser fluorescence and to develop new and simple caries activity test using laser fluorescence. The experimental design of this study consists of three parts. In first part, a new method for the in vitro assessment of changes in initial enamel caries lesion of Bovine teeth using laser fluorescence is tested. In second part, in vivo assessment undertaken. Number of teeth which showed incipient carious lesion on buccal surface examined by laser fluorescence was compared with the caries activity test of $Cariescreen^{(R)}$ test and other oral environmental test of dDfFtT. In third part, new caries activity test measured by laser fluorescence was developed on the basis of above results and evaluated the sensitivity, specificity, and diagnostic power. Optical density measured by laser fluorescence was increased as increasing the depth of incipient carious lesion and showed high correlation$(\gamma=0.7015)$ with lesion depth. Optical density showed direct proportion to lesion depth. Linear equation was obtained between the optical density and the lesion depth by regression analysis. The result of caries activity test with laser fluorescence showed high correlation with those of $Cariescreen^{(R)}$ test and dDfFtT examination. Caries activity test with laser fluorescence showed 48% of sensitivity, 52% of specificity, and 45% of diagnostic power on the basis of dDfFtT examination, and also showed 48% of sensitivity, 51% of specificity, and 36% of diagnostic power on the basis of $Cariescreen^{(R)}$ test. In regard above result, caries activity test with laser fluorescence considered to be reliable for caries activity test compared with other oral environmental test. and it was also considered to be practical because it would be simple, inexpensive, and time saving method.