• Journal of Life Science
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• v.8 no.5
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• pp.509-519
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• 1998

The effect of N-Nitrosodimethylamine(NDMA) on the glycoconjugates of rat lingual salivary gland was examined by prelectin histochemical methods. Sprague-Dawley rats weighing about 250-300g were divided into control and experimental groups. Each rat of experimental groups was administrated NDMA(17mg/kg) orally and sacrificed in 3, 6, 12, 24, 48, 72, 96 and 120 hours after NDMA administration. The regional differences and change of glycoco-njugates were elucidated by prelectin histochemical methods, such as periodic acid Schiff's(PAS) reaction, alcian blue (AB) pH 2.5, AB pH 0.4, AB pH 2.5-PAS, aldehyde fuchsin(AF) pH 1.7-AB pH 2.5 and high iron diamine(HID)-AB pH 2.5 staining. The major morphological changes in the von Ebner’s gland of NDMA administrated groups were withering and des-truction of serous acini, diminution and disappearance of cytoplasmic granules and vacuolation in cytoplasm of serous cells, and mucinous changes of duct epithelial cells. These changes were noted in NDMA administrated groups for 12 to 72 hours. In the lingual mucous gland of NDMA administrated groups, the major morphological changes were enlargement, fusion and destruction of mucous acini, loss of cytoplasmic granules and vacuolated generation in cytop-lasm of mucous cells, and mucinous change of duct epithelial cells. These changes were severe in NDMA administra-ted groups for 12 to 72 hours. In NDMA administrated groups of lingual von Ebner's gland for 12 and 72 hours, the neutral glycoconjugates be-come diminished remarkably compared to the control group. The decreased amount of neutral glycoconjugates tended to be gradually recovered from 96 hours group. The acidic glycoconjugates which were not detected in control group were found in a few serous cells of these gland of NDMA administrated groups for 6 to 48 hours and 120 ho-urs. The remarkable decrease of neutral and acidic glycoconjugates was observed in the lingual mucous glands 3, 24 and 48 hours after NDMA administration, and the striking decrease of acidic glycoconjugates was found in 72 hours groups. Among acidic glycoconjugates, sulfated glycoconjugates tended to decrease in NDMA administrated groups for 72 hours, while sialic glycoconjugates were increased in NDMA administrated groups for 3, 12 and 48 hours.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.2
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• pp.197-207
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• 2001

Development of new ceramics and esthetic needs of patients increase the use of all ceramic restorations. Fractured teeth often need metal post and core as foundation for final restoration. When all ceramic restorations are planned, metal post and core may lead to compromised esthetics because of opacity and gray color of metal post and core. Many techniques have been proposed to solve this problem such as application of an opaque porcelain to the metal core or all ceramic post and core. This study was performed to evaluate effect on color of Empress 2 crown according to various post systems. Color was evaluated by the CIE $L^*a^*b^*$ systems and measured by spectrophotometer (Model CM-3500, Minolta, Japan). Specimens were divided into 4 groups as follows Group 1 : gold cast post specimen + Empress 2 crown specimen Group 2 : application of an opaque porcelain to gold cast post specimen + Empress 2 crown specimen Group 3 : cosmopost specimen + Empress 2 crown specimen Group 4 : In-ceram post specimen + Empress 2 crown specimen. The results obtained as follows, 1. $L^*$ Values showed that group 2, 3, 4 were higher than group 1 with significant difference and group 2, 3, 4 were not significantly different. 2. $a^*$ Values and $b^*$ values also showed that group 2. 3, 4 were higher than group 1 with significant difference and group 2, 3, 4 were not significantly different. 3. ${\Delta}E^* ab$ Values showed that ${\Delta}E^* ab$ 3 was the highest value and ${\Delta}E^* ab$ 5 was the lowest value.

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.508-514
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• 2006

In this study, we have performed ab initio computer simulations to investigate the conformational and complexation characteristics of the trimethyl ether of p-tert-butylmonodeoxycalix[4]arene (6) with a potassium ion. The structures of different conformers of 6 and their potassium complexes were optimized by using ab initio RHF/6-31G and B3LYP/6-31G(d,p) methods. The relative stability of the various conformers of the uncomplexed 6 is in following order: cone (most stable) > 1-partial-cone ~ 2i-partial-cone > 2-partial-cone ~ 1,3-alternate > 3i-partial-cone. However, the relative stability of the conformational complexes of 6 with $K^+$ is in the following order: 2-partial cone ~ 1,3-alternate > cone > 3-partial cone > 1-partial cone (least stable). The highest binding strengths of 2-partial-cone and 1,3-alternate complexes originate from two strong cation-$\pi$ interactions and two strong cation-oxygen interactions in the complex of 6+$K^+$. Due to the cation-$\pi$ interactions, the calculated C-C bond distances in the arenes of the $K^+$-complexes are about 0.0048 $\AA$ longer than the values of their isolated hosts.

• Tuberculosis and Respiratory Diseases
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• v.78 no.3
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• pp.218-226
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• 2015

Background: Eph receptors and ephrin ligands have several functions including angiogenesis, cell migration, axon guidance, fluid homeostasis, oncogenesis, inflammation and injury repair. The EphA2 receptor potentially mediates the regulation of vascular permeability and inflammation in response to lung injury. Methods: Mice were divided into 3 experimental groups to study the role of EphA2 signaling in the lipopolysaccharide (LPS)-induced lung injury model i.e., IgG+phosphate-buffered saline (PBS) group (IgG instillation before PBS exposure), IgG+LPS group (IgG instillation before LPS exposure) and EphA2 monoclonal antibody (mAb)+LPS group (EphA2 mAb pretreatment before LPS exposure). Results: EphA2 and ephrinA1 were upregulated in LPS-induced lung injury. The lung injury score of the EphA2 mAb+LPS group was lower than that of the IgG+LPS group ($4.30{\pm}2.93$ vs. $11.45{\pm}1.20$, respectively; p=0.004). Cell counts (EphA2 mAb+LPS: $11.33{\times}10^4{\pm}8.84{\times}10^4$ vs. IgG+LPS: $208.0{\times}10^4{\pm}122.6{\times}10^4$; p=0.018) and total protein concentrations (EphA2 mAb+LPS: $0.52{\pm}0.41mg/mL$ vs. IgG+LPS: $1.38{\pm}1.08mg/mL$; p=0.192) were decreased in EphA2 mAb+LPS group, as compared to the IgG+LPS group. In addition, EphA2 antagonism reduced the expression of phospho-p85, phosphoinositide 3-kinase $110{\gamma}$, phospho-Akt, nuclear factor ${\kappa}B$, and proinflammatory cytokines. Conclusion: This results of the study indicated a role for EphA2-ephrinA1 signaling in the pathogenesis of LPS-induced lung injury. Furthermore, EphA2 antagonism inhibits the phosphoinositide 3-kinase-Akt pathway and attenuates inflammation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.123-129
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• 2015

There are two kinds of cartons for beverage packaging, one is aseptic brick (AB) type and the other is gable top (GT). In this study, AB and GT were used as a raw material of recycled paper to investigate the recyclability at their varied blending ratios. Fiber consistency at pulping decreased as the blending ratio of AB increased. As a result, a lot of fines were generated from AB and flakes from GT increased because shear force in pulper decreased. Bulk of handsheets was more than $2.0cm^3/g$, and ISO brightness decreased as the blending ratio of AB increased. The best condition to recycle beverage cartons is to discriminate each cartons separately because of differences in the composition. However, there are problems such as the limit of the collection system and social costs. Therefore, it is assumed that the blending ratios of AB should be adjusted at less than 20% for effective recycling of beverage cartons.

• Journal of Hydrogen and New Energy
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• v.10 no.2
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• pp.141-149
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• 1999

Recently the Ni/MH secondary battery has been studied extensively to achieve higher energy density, longer cycle life and faster charging-discharging rate etc. In this work, the electrode properties of $(LM)Ni_{4.49}Co_{0.1}Mn_{0.205}Al_{0.205}$ alloy and $Ti_{0.6}Zr_{0.4}V_{0.6}Ni_{1.4}$ alloy with addition of Pd were investigated. These alloys did not show any change in XRD pattern by Pd addition. As Pd was added as alloy element, the activation behavior was not affected significantly in both $AB_2$ type and $AB_5$ type electrodes and, On charging and discharging in high current density, Discharge capacity with increasing of Pd content was more decreased. But cycle life was showed increasing. Especially the electrode of $Ti_{0.6}Zr_{0.4}V_{0.6}Ni_{1.4}+0.5wt%$ Pd alloy was not almost decreased discharge capacity for 400cycles.

• Journal of Hydrogen and New Energy
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• v.11 no.4
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• pp.189-202
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• 2000

$AB_2$ type Zr-based Laves phases alloys have been studied for potential application as a negative electrode in a Ni-MH battery. The $AB_2$-type electrodes have a much higher energy density than $AB_5$-type electrodes per weight, however they have some disadvantages such as poor activation behavior and cycle life etc. Nonetheless, the $AB_2$-type electrodes have been studied very extensively due to their high energy density. In this study, in order to develop the cycle life, the Mn of $AB_2$ alloy composition was substituted partially by Mo. The alloys were melted by arc furnace and remelted 4-5 times for homogeneity. The alloy powder was used below 200-325 mesh for experiments. The structures and phases of the alloys were analyzed by XRD, SEM and EDS, and measured the curve of a pressure-composition isotherms. The electrodes were prepared by cold pressing of the copper-coated(25 wt%) alloy powders, and tested by a half cell. The results are summarized as follows. The cycle life was improved with the increase of Mo amount in $Zr_{1-x}Ti_xV_{0.4}Ni_{1.2}Mn_{0.4}Mo_y$(x=0.3, 0.4) and the activation was faster, whereas the discharge capacity decreased.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.124-129
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• 2006

The grades of burley tobacco stems and scraps were classified followed by the nicotine and nitrate contents by using the cluster analysis. The chemical components of the burley tobacco stems and scraps gathered from 2002 to 2005 were analyzed with auto analyzer. According to the nicotine contents and the nitrate contents, the burley stems and scraps could be classified three groups, respectively. In case of the burley scraps, the AB3T, AB4TR, B1T and B2T grades belonged to the $1^{st}$ a group. The C1W and C2W grades belonged to the $2^{nd}$ group and the CD3W and CD4TR belonged to the $3^{rd}$. In case of the burley stems, the AB3T and AB4TR grades belonged to the $1^{st}$ group. The B1T, B2T, C1W and C2W grades belonged to the $2^{nd}$ group and the CD3W and CD4TR belonged to the $3^{rd}$ group. This classification of raw materials depending on the similarity in the chemical components might be helpful to control the properties of the Reconstituted Tobacco sheet.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.6
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• pp.1170-1176
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• 2002

We examined the effects of Whadamcheongwha-tang(WDCWT) extract on the acetic-acid induced antigastric ulcer in rats. These experiments investigated the numerical changes of gastrin and histamine secreting cells of the gastric mucosa by immunohistochemical method, and the changes of mucin of gastric mucosa by PAS-AB stain methods after the oral administration of WDCWT extract(1.0ml/day) and omeprazole(0.2mg/day) for 1, 3 and 6 weeks. The result are as follows; 1. When WDCWT extract was administrated for 1, 3, 6 weeks, in result, gastrin secreting cells in gastric mucosa were increased compared to the control group. 2. When WDCWT extract was administrated for 1, 3, 6 weeks, in result, the density of immunoreactive gastrin cells was increased compare to the control group. 3. When WDCWT extract was administrated for 1, 3, 6 weeks, in results, the changs of mucosal thickness stained by PAS/PAS-AB was increased compared to the control group. 4. When WDCWT extract was administrated for 1, 3, 6 weeks, in results, the density of PAS stain was decreased compare to control group, but density of AB stain was increased compare to control group. The results suggest that WDCWT extract inhibits a gastric acid secretion in rat gastric mucosa, and is useful in the treatment of the hyperacidity and gastric ulcer.

• Journal of the Korean Chemical Society
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• v.50 no.4
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• pp.291-297
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• 2006

The equilibrium structures, relative energies and NBO analyses for the possible conformations and transition states which can exist on the internal rotation of CPDFB and CPCFB molecules have been investigated using DFT and ab initio methods with various basis sets. The interaction between bonding orbital ((C1-C3, C2-C3)) and antibonding orbital (n*(B9) and *(B9-Cl11)) was the main characteristic hyperconjugation in both molecules. In addition, the stabilization energy of CPDFB was 6.63kcal/mol and that of CPCFB was 6.97(E-form)/6.79(Z-form) kcal/mol for each conformation. The rotational barriers by internal rotation of BF2- and BFCl- functional groups were evaluated to be 5.3~6.7kcal/mol and 5.7~6.5kcal/mol respectively, which showed good agreement with the experimental values reported by previous dynamic NMR study. Finally, Z-form was more stable than E-form by 0.2 kcal/mol in CPCFB molecule and therefore Z-form was confirmed as global minimum.