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Magnetic resonance images of ameloblastoma

  • Kim Jae-Duk;Kim Jin-Soo
    • Imaging Science in Dentistry
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    • 제35권4호
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    • pp.207-213
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    • 2005
  • Purpose: To classify and describe the characteristic features of MRI of some ameloblastoma variants. Materials and Methods: The MR images, CT images, and panoramic radiographs in 5 cases were retrospectively examined as follows. First, the contents of ameloblastomas were devided into two portions of either solid or cystic components on the basis of MR signal intensities. The signal intensity within the solid or cystic portions was classified as homogeneous or heterogeneous. Next, the characteristic internal feature of the lesion on T1W1 or T2WI was described. The signal intensities were classified into low, intermediate, slightly high, high, and strong high signal intensity. Results: Unicystic lesion showed homogeneous high signal intensity (SI) on T2W2 and the rim enhancement of the surrounding area including the mural nodule and the thick wall except the central portion on Gd- T1W1. Solid type revealed heterogeneous and high SI area with strong high SI area on T2W2. On Gd- T1W1, the area corresponding to the low signal spot on T1W1 and the strong high signal spot on T2W1 showed low SI. Hybrid type showed slightly enhanced capsular structures and low SI for the round bony septa and the areas connecting the mixed and cystic lesions on T2Wl and Gd-T1W1. Conclusion: MRI could easily assess the relationship between the mixed and cystic findings in ameloblastoma.

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수성이상계를 이용한 재조합 hGM-CSF의 in situ 분리

  • 표세홍;명현종;김동일
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2002년도 생물공학의 동향 (X)
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    • pp.321-324
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    • 2002
  • 본 연구에서는 hGM-CSF를 생산해 배지 내로 분바하도록 유전자 조작된 Nicotiana tabacum 세포를 수성이상계 내에서 배양하여 in situ recovery를 시도하였다. 특히 식물세포 자체의 생상에 큰 영향을 주지 않으면서도 일반 배지에서 회수한 단백질에 비해 많은 양을 생산할 수 있는 수성이상계 시스템을 선정하였다. 6% (w/w) PEG 20,000과 10% (w/w) dextran 2.000,000 을 이용하는 경우 최대 세포 농도가 18.6 g/L 로, 일반배지를 사용하는 경우 (15.7 g/L)에 비해 저해가 없음을 확인하였다. 또한 목적 단백질인 hGM-CSF의 생산에 있어서도 위의 시스템의 경우 dextran-rich phase인 아랫 상으로 분배됨으로 인해 회수가 쉬울 것으로 확인되었으며 그 생산량 또한 일반배지에서의 생산량 (1.5 ng/mL)에 비해 크게 다르지 않음을 확인할 수 있었다. 따라서 hGM-CSF의 회수를 위한 in situ recovery 시스템에 있어서 수성이상계의 이용 가능성을 확인하였다.

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분말 모합금 빌렛으로부터 제조된 Ni-W 합금테이프의 기계적 성질과 집합도 (Texture and Mechanical Properties of Ni-W Alloy Tapes Fabricated from Powder Mother Billets)

  • 김민우;전병혁;지봉기;정규동;김찬중
    • 한국분말재료학회지
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    • 제14권1호
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    • pp.13-18
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    • 2007
  • The mother Ni-W (1-5 wt.%) alloy billets for coated conductor substrate were fabricated by powder metallurgy process. The tensile test results for the sintered Ni-W rods showed the increase of mechanical strength and decrease of ductility with increasing W content due to the solid solution hardening. All the fracture surfaces of the tested specimens showed the typical ductile fracture mode of dimple rupture due to the local necking. The Ni-W alloy billets were made into tape by cold rolling. After the appropriate heat treatment for recrystallization, the brass texture formed by the cold rolling was converted to the complete cube texture. The in-plane and out of plane texture of the tapes estimated by x-ray pole figure were smaller than 9 degree and 7 degree, respectively. The effect of the W addition on the texture development seems not to be significant.

환기부족 화재의 시뮬레이션 (Simulation of Under-Ventilated Fires)

  • 박외철
    • 한국화재소방학회논문지
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    • 제30권1호
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    • pp.12-16
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    • 2016
  • FDS를 사용한 환기부족 화재 시뮬레이션의 문제점을 재확인하고 FDS의 환기부족 화재 판단기준을 제시하기 위하여 ISO 9705 화재실 내 1000~3000 kW의 프로판 화재에 대한 시뮬레이션을 수행하였다. 화재규모가 2000 kW 이상일 때 1500 kW의 경우보다 온도가 낮게 예측됨을 확인하였다. FDS를 사용할 때 환기부족 화재에서는 화재규모가 증가해도 산소부족으로 열방출률은 증가하지 않았다. 이에 따라 화재 시뮬레이션에 있어서의 환기부족 화재 판단기준으로 열방출률이 사용될 수 있으며, ISO 9705 화재실에서는 화재규모가 1700 kW 이상일 때 환기부족 화재가 예측됨을 알 수 있었다.

Influence of Genotoxic Heterocyclic Aromatic Amine Formation and Overall Mutagenicity in Ground Beef Patties Using Korean Bramble (Rubus coreanum Miquel)

  • Lee, Jae-Hwan;Shin, Han-Seung
    • Food Science and Biotechnology
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    • 제16권4호
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    • pp.576-579
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    • 2007
  • The effects of temperature and Korean bramble (Rubus coreanum Miquel) tissue concentrate on heterocyclic aromatic amine (HAA) formation in fried ground beef patties were investigated. Various amounts of Korean bramble tissue (4.0, 7.0, and 11.0%, w/w) were added to ground beef patties were fried at 2 different temperatures (190 and $225^{\circ}C$) for 10 min/side. It was observed in the fried ground beef patties fried at $190^{\circ}C$ with the addition of 11.0%(w/w) Korean bramble that the mutagenicity decreased by 64%, and formation of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-I-methyl-6-phenylimidazo[4,5-b]-pyridine(PhIP) reduced by 55 and 86%, respectively. Although no difference in total mutagenicity was shown in patties fried at $225^{\circ}C$ with the addition of 4.0, 7.0, and 11.0%(w/w), different levels of reduction of PhIP formation in patties fried at $225^{\circ}C$ with the addition of 4.0, 7.0, and 11.0%(w/w) were shown 49, 63, and 75%, respectively.

Electrodeposited Ni-W-Si3N4 alloy composite coatings: Evaluation of Scratch test

  • Gyawali, Gobinda;Joshi, Bhupendra;Tripathi, Khagendra;Lee, Soo Wohn
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2014년도 추계학술대회 논문집
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    • pp.178-179
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    • 2014
  • In this study, $Ni-W-Si_3N_4$ alloy composite coatings were prepared by pulse electrodeposition method using nickel sulfate bath with different contents of tungsten source, $Na_2WO_4.2H_2O$, and dispersed $Si_3N_4$ nano particles. The structure and microstructure ofcoatings was separately analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). Results indicated that nano $Si_3N_4$ and W content in alloy had remarkable effect on microstructure, microhardness and scratch resistant properties. Tungsten content in Ni-W and $Ni-W-Si_3N_4$ alloy ranged from 7 to 14 at.%. Scratch test results suggest that as compared to Ni-W only, $Ni-W-Si_3N_4$ prepared from Ni/W molar ratio of 1:1.5 dispersed with 20 g/L $Si_3N_4$ has shown the best result among different samples.

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Effects of Carrageenan on the Gelatinization of Salt-Based Surimi Gels

  • Eom, Sung-Hwan;Kim, Jung-Ae;Son, Byoung-Yil;You, Dong Hyun;Han, Jeong Min;Oh, Jung-Hwan;Kim, Bong-Yeun;Kong, Chang-Suk
    • Fisheries and Aquatic Sciences
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    • 제16권3호
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    • pp.143-147
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    • 2013
  • The influence of carrageenan addition on the gelatinization of salt-based surimi gels was investigated by measuring compressive properties and Hunter color scale values. Hydrocolloid kappa (${\kappa}$)-carrageenan at 0%, 0.2%, and 1.0% and NaCl (2% w/w), KCl (1.5% w/w), and a mixture of NaCl (2% w/w) and KCl (1.5% w/w), were added to Alaska pollock surimi. Gel compressive properties were assessed by measuring the breaking force and gel strength. The gelling property of ${\kappa}$-carrageenan-induced surimi gel was significantly increased by the incorporation of KCl rather than NaCl. The addition of ${\kappa}$-carrageenan increased the breaking force and gel strength of surimi gels. Gels with 1% ${\kappa}$-carrageenan and KCl had the highest breaking force and gel strength. The addition of ${\kappa}$-carrageenan caused an increase in the whiteness values of the surimi gels.

Antifilarial activity of Nigella sativa on Setaria cervi-an in vitro study

  • Rizvi, Waseem;Kumar, Anil;Rizvi, NH;Ahmad, Razi;Singhal, KC;Khan, Atif
    • Advances in Traditional Medicine
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    • 제5권3호
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    • pp.240-245
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    • 2005
  • The effect of aqueous and alcoholic extract of seeds of Nigella sativa (N. sativa) was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of Setaria cervi (S. cervi). Both the extracts caused inhibition of spontaneous movements of the w.w and n.m complex characterized by initial stimulation followed by irreversible paralysis, with the exception that aqueous extract produced a partially reversible paralysis of w.w preparation. Lesser concentration of both the extracts was required to inhibit the movements of n.m complex than the w.w. Suggesting a cuticular permeability barrier. The lethal concentration $50\;(LC_{50})$ and lethal concentration $90\;(LC_{90})$ were 30 and 55 ng/ml for aqueous and 45 and 60 ng/ml for alcoholic extracts respectively.

$\beta-cyclodextrin$ 및 유도체의 포접체 형성에 의한 LG 106W의 유용성 및 안정성 개선에 관한 연구 (Improvement in availability and stability of to 106w by inclusion with $\beta-cyclodextrin$ and its derivatives)

  • 정성훈;이천구;조완구;강세훈
    • 대한화장품학회지
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    • 제25권1호
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    • pp.120-136
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    • 1999
  • A newly synthesized polyhydroxy aromatic compound(LG 106w) has good skin lightening effect. Inclusion complexation of LG 106w with $\beta$-cyclodextrin and its hydroxypropyl and dimethyl derivatives was studied by the solubility method, scanning electron microscopy and differential thermal analysis. A relationship between host and guest was clearly reflected in the magnitude of the stability constant(DM-$\beta$> HP-$\beta$>$\beta$ -cyclodextrin). Formulation problems, which resulted from its very low solubility in aqueous solution, were resolved by the inclusion formation. LG 106W from inclusions is much more water-soluble than pure one. The improvement of pH and temperature stability correlated with the increased solubility was also observed. Inclusion complex of LG 106w had similar activity to pure LG 106w on the inhibition of melanin synthesis in B-16 melanoma cell but showed lower irritation on cultured cell test in vitro. According to the results, cyclodextrins might be one of the reliable candidates for improving the availability of LG 106w.

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Identification and Phylogeny of the Human Endogenous Retrovirus HERV-W LTR Family in Cancer Cells

  • Yi, Joo-Mi;Kim, Hwan-Mook;Kim, Heui-Soo
    • Animal cells and systems
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    • 제6권2호
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    • pp.167-170
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    • 2002
  • The long terminal repeats (LTRs) of human endogenous retrovirus (HERV) have been found to be coexpressed with sequences of closely located genes. It has been suggested that the LTR elements have contributed to the structural change or genetic variation of human genome connected to various diseases and evolution. We examined the HERV-W LTR elements in various cancer cells (2F7, A43l , A549, HepG2, MIA-PaCa-2, PC-3, RT4, SiHa, U-937, and UO-31). Using genomic DNA from the cancer cells, we performed PCR amplification and identified twelve new HERV-W LTR elements. Those LTR elements showed a high degree of sequence similarity (88-99%) with HERV-W LTR (AF072500). A phylogenetic tree obtained by the neighbor-joining method revealed that HERV-W LTR elements could be mainly divided into two groups through evolutionary divergence. Three HERV-W LTR elements (RT4-2, A43l-1, and UO3l-2) belonged to Group 1, whereas nine LTR elements (2F7-2, A549-1, A549-3, HepG2-3, MP2-2, PC3-1, SiHa-8, SiHa-10, and U937-1) belonged to Group 11. Taken together, our new sequence data of the HERV-W LTR elements may contribute to an understanding of tissue-specific cancer by genomic instability of LTR integration.