• Journal of Powder Materials
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• v.6 no.2
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• pp.152-162
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• 1999

The present study is concerned with the effect of PM process variables on the microstructure by using atomized superalloy powders. It is suggested that the inhomogeneity of composition is strongly dependent on the process variables. The contents of segregation elements of plasma rotating electrode process (PREP) powders are larger than those of Ar atomization (AA) powders. As HIP treatment temperature in-increases, the secondary phases on the prior particle boundaries (PPB) have continuous,uniform distribution and high density, but the amount of PPB decreases suddenly at 1150$^{\circ}$C. Segregated phases on the PPB are identified to be MC type carbide. Brittle MC type carbides on the PPB provide fracture initiation sites and preferred fracture path, thereby leading to intergranular type brittle fracture.

• Korean Journal of Plant Taxonomy
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• v.49 no.4
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• pp.371-373
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• 2019

While conducting a floristic study of Korean moss, we discovered one unrecorded species collected from Mt. Hallasan in Korea. Brachydontium olympicum (E. Britton) T. T. McIntosh & J. R. Spence is recorded for the first time for Korea. Unlike other species of Brachydontium, this species has no peristome and its distal laminal cells are mostly isodiametric.

• Journal of Species Research
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• v.8 no.1
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• pp.128-135
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• 2019

Two euplotid ciliates, Euplotes encysticus Yonezawa, 1985 and E. rariseta Curds et al., 1974, were isolated from a freshwater pond called Mulgol in Dokdo of the East Sea and from Masan Bay/Jeju Island, Korea, respectively. Both species are redescribed based on live observations and protargol impregnation. Cells of Euplotes encysticus are asymmetrically oval, $63-79{\times}41-61{\mu}m$ in vivo and capable of encystment. The cells have 31-36 adoral zone of membranelles(AZM), 9 fronto-ventral cirri (FVC), 5 transverse cirri (TC), 2-3 caudal cirri (CC), 2 marginal cirri (MC), 7 dorsal kineties (DK), and 19-22 dorsal cilia in middle DK. The cells of Euplotes rariseta has a small ovoid form and are $32-44{\times}23-35{\mu}m$ in vivo, 18-22 AZM, 10 FVC, 5 TC, 2 CC, 1 MC and 6 DK.

• Imaging Science in Dentistry
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• v.33 no.3
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• pp.179-185
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• 2003

Purpose: To investigate the effects of irradiation on the phenotypic expression of the MC3T3-El osteoblastic cell line, particularly on the expression of osteocalcin and osteopontin. Materials and Methods: Cells were irradiated with a single dose of 0.5, 1,4, and 8 Gy at a dose rate of 5.38 Gy/min using a cesium 137 irradiator. After the specimens were harvested, RNA was extracted on the 3rd, 7th, 14th, and 21st day after irradiation. The RNA strands were reverse-transcribed and the resulting cDNAs were subjected to amplification by PCR. Results: The irradiated cells demonstrated a dose-dependent increase in osteocalcin and a dose-dependent decrease in osteopontin mRNA expression compared with the non-irradiated control group, The amount of osteocalcin mRNA expression decreased significantly at the 3rd day after irradiation of 0,5, 1,4, and 8 Gy, and also decreased significantly at the 3rd, 14th, and 21 st day after irradiation in the 8 Gy exposed group compared with the control group, The degree of osteopontin mRNA expression increased significantly at the 7th day after irradiation of 0,5, 1,4, and 8Gy, Conclusion: These results showed that each single dose of 0,5, 1, 4, and 8 Gy influenced the mRNA expression of osteocalcin and osteopontin associated with the calcification stage of osteoblastic cells, suggesting that each single dose affected bone formation at the cell level.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.743-752
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• 1993

To elucidate the effects of natural gums, i.e. carrageenan, locust bean gum and xanthan gum and synthetic gums, i.e. carboxymethyl cellulose(CMC) and methyl cellulose(MC) on the foaming properties of sodium caseinate, surface tension, absolute viscosity, turbidity, foaming ability, foam stability, and heat stability of the foams of the caseinate solutions with added gums were examined. The surface tension of sodium caseinate solution(5%) adding to gums at pH 4.0 and 5.0 were higher than those at pH 7.0 and 8.0. The viscosities of the solutions adding to gums(0.1, 0.2, 0.3 and 0.5%) ap pH 4.0, 5.0, 7.0 and 8.0 were 2.4~170.0, 2.5~190.0, 5.3~180.0 and 6.3~99.0 cps, respectively. Especially xanthan gums predominantly increased the viscosity. Turbidities were 97.3~98.2 at pH 4.0 and 5.0 and 93.0~95.8 at pH 7.0 and 8.0. Foaming abilities of the solution adding to xanthan gum, carrageenan and locust bean gum were increased, while those of CMC and MC were decreased. Additions of xantham gum, CMC and MC increased the foam stability, especially xanthan gum did predominantly. Xanthan gum, MC and locust bean gum were more effective than CMC and carrageenan for heat stability. For improving the foaming properties of sodium caseinate xanthan gum were best of five kinds of gums. Surface tensions and turbidities of the solution were related to foaming ability, and the viscosities were related to foam stability and heat stability.

• Toxicological Research
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• v.30 no.4
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• pp.261-266
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• 2014

Environmental pollutants such as polycyclic aromatic hydrocarbons (PAHs) have been implicated in cancer development and progression. However, the effects of PAHs on carcinogenesis are still poorly understood. Here, we characterized a mouse cancer cell line BNL 1ME A. 7R.1 (1MEA) derived by transformation of non-tumorigenic liver cell line BNL CL.2 (BNL) using 3-methylcholanthrene (3MC), a carcinogenic PAH. RT-PCR and immunoblot analysis were used to determine the expression level of mRNA and proteins, respectively. To determine functionality, cell motility was assessed in vitro using a transwell migration assay. Both mRNA and protein levels of E-cadherin were significantly decreased in 1MEA cells in comparison with BNL cells. While the expression levels of mesenchymal markers and related transcription factors were enhanced in 1MEA cells, which could lead to increase in cell motility. Indeed, we found that 7-day exposure of BNL cells to 3-MC reduced the level of the adhesion molecule and epithelial marker E-cadherin and increased reciprocally the level of the mesenchymal marker vimentin in a dose-dependent manner. Taken together, these results indicate that the process of epithelial-mesenchymal transition (EMT) may be activated during premalignant transformation induced by 3-MC. A mechanism study to elucidate the relation between 3-MC exposure and EMT is underway in our laboratory.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.13 no.2
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• pp.120-125
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• 2013

Purpose: McCune-Albright syndrome (MAS) is caused by activating mutations in the GNAS gene, resulting in peripheral precocious puberty, caf$\acute{e}$-au-lait spots, and polyostotic fibrous dysplasia (POFD). The aim of the present study was to describe the diverse clinical and endocrine characteristics of patients with MAS. Methods: Seven patients with MAS were included in this study and medical charts were reviewed retrospectively for following parameters: patient's sex and age at diagnosis, POFD, ovarian cysts, and precocious puberty. Results: The mean age at diagnosis was $5.8{\pm}4.2$ years. One patient was male (14%) and the other six patients were female (86%). Peripheral precocious puberty was associated with 6 patients (86%). Five patients manifested premature menarche as early as 2 to 5 years of age. Letrozole was administered to 4 patients, tamoxifen to one patient and GnRH agonist to one patient. Five females developed ovarian cysts. Thyroid function tests were performed in all patients and one patient showed hyperthyroidism (14%) and has been treated with methimazole. One patient presented with pseudohypoparathyroisdism, phosphaturia, calciuria suggesting hypophosphatemic rickets. Six patients (86%) revealed POFD. One patient had symptoms of optic nerve compression and secondary esotropia and 2 patients had bone pain. Conclusion: This study described clinical characteristics and endocrine complications of patients with MAS. Careful physical examinations with history taking and serial endocrine function tests should be needed to detect complications such as endocrinologic hyperfunction and POFD.

• 대한치주과학회:학술대회논문집
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• 1997.11a
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• pp.105-106
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• 1997

• 대한치주과학회:학술대회논문집
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• 1997.11a
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• pp.34-34
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• 1997

• 대한치주과학회:학술대회논문집
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• 1997.11a
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• pp.107-107
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• 1997