• Restorative Dentistry and Endodontics
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• 제9권1호
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• pp.101-106
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• 1983

It was the purpose of this study to investigate the fracture mode of dental amalgam by observing the crack propagation, and to relate this to the microstructure of the amalgam. Caulk 20th Century Regular, Caulk Spherical, Dispersalloy, and Tytin amalgam alloys were used for this study. After each amalgam alloy and Hg measured exactly by the balance was triturated by the mechanical amalgamator (Capmaster, S.S. White), the triturated mass was inserted into the cylindrical metal mold which was 4 mm in diameter and 12 mm in height and was pressed by the Instron Universal Testing Machine at the speed of 1mm/min with 120Kg. The specimen removed from the mold was stored in the room temperature for a week. This specimen was polished with the emery papers from #100 to #200 and finally on the polishing cloth with 0.06${\mu}Al_2O_3$ powder suspended in water. The specimen was placed on the Instron testing machine in the method similar to the diametral tensile test and loaded at the crosshead speed of 0.05mm/min. The load was stopped short of fracture. The cracks on the polished surface of specimen was examined with scanning electron microscope (JSM-35) and analyzed by EPMA (Electron probe microanalyzer). The following results were obtained. 1. In low copper lathe-cut amalgam, the crack went through the voids and ${\gamma}_2$ phase, through the ${\gamma}_1$ phase around the ${\gamma}$ particles. 2. In low copper spherical amalgam, it was observed that the crack passed through the ${\gamma}_2$ and ${\gamma}_1$ phase, and through the boundary between the ${\gamma}_1$ and ${\gamma}$ phase. 3. In high copper dispersant (Dispersalloy) amalgam, the crack was found to propagate at the interface between the ${\gamma}_1$ matrix and reaction ring around the dispersant (Ag-Cu) particles, and to pass through the Ag-Sn particles. 4. In high copper single composition (Tytin) amalgam, the crack went through the ${\gamma}_1$ matrix between ${\eta}$ crystals, and through the unreacted alloy particle (core).

• 대한한방내과학회지
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• 제28권4호
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• pp.902-910
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• 2007

Objective : Peroxisome proliferator-activated receptor (PPAR)-gamma, a transcription factor in adipocyte differentiation, has important effects on insulin sensitivity, atherosclerosis, endothelial cell function and inflammation. Through these effects, PPAR-gamma2 might be involved with type 2 diabetes and vascular disease, including diabetic complications. Recently, it has been reported that the C161T polymorphism in the exon 6 of PPAR-gamma is associated with type 2 diabetes interacting with uncoupling protein 2 (UCP2) gene, and is associated with acute myocardial infarction. We studied the association of this polymorphism with type 2 diabetes and its complications, such as retinopathy, ischemic stroke, nephropathy and neuropathy in Korean non-diabetic and type 2 diabetic populations. Methods : Three hundred and thirty eight type 2 diabetic patients (retinopathy: 64, ischemic stroke: 67, nephropathy: 39 and neuropathy: 76) and 152 healthy matched control subjects were evaluated. The PPAR-gamma C161T polymorphism was analyzed by PCR-RFLP. Results : PPAR-gamma C161T genotype and allele frequency did not show significant differences between type 2 diabetic patients and healthy controls (T allele: 17.0 vs. 14.5, OR= 1.21, P=0.3188). In the analysis for diabetic complications, T allele in diabetic nephropathy was significantly higher than controls (P=0.0358). T allele in the ischemic stroke patients was also higher than healthy controls, although it had no significance (P=0.1375). Conclusions : These results suggest that the C161T polymorphism of the PPAR-gamma gene might be associated with diabetic nephropathy in type 2 diabetes.

• 분석과학
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• 제6권5호
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• pp.501-508
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• 1993

$^{241}Am-Be$(${\alpha}$, n) 중성자 선원의 중성자/감마선(n/${\gamma}$) 복합 방사선장에서 $^6Li$(n, ${\alpha}$)T 핵반응을 이용하고 두 섬광체, BC 501($C_8H_{10}$)과 Cerium의 섬광 감쇠 시간차와 동일 섬광체 내에서의 n/${\gamma}$에 대한 서로 다른 섬광감쇠 시간차를 병용하여 PSD(Pulse Shape Disciminator) 및 CFD(Constant Fraction Discriminator) 방법으로 n와 ${\gamma}$성분을 분리 측정하였으며 $^6Li$ 속중성자 분광계의 figure of merit는 1.36으로 평가되었다.

• Journal of Animal Science and Technology
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• 제57권11호
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• pp.40.1-40.7
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• 2015

Background: Activation of peroxisome proliferator activated receptor gamma ($PPAR{\gamma}$) in the alveolar macrophages (AM) by selective synthetic $PPAR{\gamma}$ ligands, improves the ability of the cells to resolve inflammation. In birds, respiratory macrophages are known as free avian respiratory macrophages (FARM) and show distinct functional differences from AM. The effects of treating FARM with $PPAR{\gamma}$ ligands are unclear. Methods: FARM were harvested by lavage of chicken respiratory tract and their morphology assessed at microscopic level. The effects of $PPAR{\gamma}$ agonists on the FARM in vitro viability, phagocytic capacity and proinflammatory cytokine (TNF-${\alpha}$) production were assessed. Results: FARM had eccentric nucleus and plasma membrane ruffled with filopodial extensions. Ultrastructurally, numerous vesicular bodies presumed to be lysosomes were present. FARM treated with troglitazone, a selective $PPAR{\gamma}$ agonist, had similar in vitro viability with untreated FARM. However, treated FARM co-cultured with polystyrene particles, internalized more particles with a mean volume density of 41 % compared to that of untreated FARM of 21 %. Further, treated FARM significantly decreased LPS-induced TNF-${\alpha}$ production in a dose dependent manner. Conclusion: Results from this study show that $PPAR{\gamma}$ synthetic ligands enhance phagocytic ability of FARM. Further the ligands attenuate production of proinflammatory cytokines in the FARM, suggesting potential therapeutic application of $PPAR{\gamma}$ ligands in the management of respiratory inflammatory disorders in the poultry industry.

• 한국식품위생안전성학회지
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• 제23권1호
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• pp.85-89
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• 2008

가열 조리된 냉장 돼지고기 패티에 사용된 상업용 유통 ${\gamma}$-oryzanol과 ${\alpha}$-tocopherol의 항산화 효과가 돼지고기 육질 내의 지질 산화로부터 기인되는 warmed-over flavor(WOF) 값과 콜레스테롤 산화로부터 기인되는 이차 산화물인 7-ketocholesterol의 생성 추이 변화로 비교 분석되었다. 지질산화로부터 측정된 파라미터는 이화학 데이터인 TBARs 값과 관능 데이터인 WOF 값에 의해 비교 분석되었으며, 콜레스테롤 산화로부터 유래된 측정 파라미터는 산화 유도기간에 따른 가열 조리된 돼지고기의 콜레스테롤 함량 변화 정도와 주요 콜레스테롤 산화물인 7-ketocholesterol 생성 정도에 의해 비교 분석 되었다. 콜레스테롤과 롤레스테롤 산화물은 cold saponification 추출 기법과 고속액체크로마토그래프 (HPLC) 테크닉을 이용하여 정량적으로 분석되었다. 아울러, 측정된 각 파라미터 변수들 간의 통계적 상관관계가 검토되었으며, 가열 조리된 돼지고기 패티의 산화로부터 기인되는 이차 산화물에 대한 ${\gamma}$-oryzanol과 ${\alpha}$-tocopherol의 항 산화력이 비교 분석되었다. 분석 결과 모든 파라미터 변수들은 서로 간에 유의적인 상관관계를 나타내었으며, 특히, ${\gamma}$-oryzanol처리 군에서 유의적인 지질 및 콜레스테롤 항 산화 효과를 보였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2699-2703
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• 2012

The functional significance of the proteasome activator $REG{\gamma}$ in the regulation of cell proliferation and apoptosis has been recognized. However, pathological contributions to tumor development remain to be elucidated. Both oncogenic proteins and tumor suppressors are targeted by $REG{\gamma}$ for proteasomal degradation. It has been proposed that the role of the $REG{\gamma}$ in the pathogenesis of cancer is cell- and context-specific. In this study, we aimed to explore the potential involvement of $REG{\gamma}$ in laryngeal carcinomas, comparing protein expression in tumor and adjacent tissues by immunohistochemical staining and Western blot analysis. We also characterized the correlation between the expression of $REG{\gamma}$ and the previously identified substrates p53 and p21. We showed that $REG{\gamma}$ was abnormally highly expressed in cancer tissues. Statistical analysis revealed that there was a positive relationship between the level of $REG{\gamma}$ and the expression of p53 and p21. Our study suggests that $REG{\gamma}$ overexpression can facilitate the growth of laryngeal cancer cells.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1339-1346
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• 2013

Conventional chemotherapeutic regimens often accompany severe side effects and fail to induce complete regression of chemoresistant or relapsing metastatic cancers. The need for establishing more efficacious anticancer strategies led to the development of a combined modality treatment of chemotherapy in conjunction with immunotherapy or radiotherapy. It has been reported that poly-gamma-glutamate (${\gamma}$-PGA), a natural polymer composed of glutamic acids, increases antitumor activity by activating antigen-presenting cells and natural killer (NK) cells. Here, we investigated the antitumor effect of ${\gamma}$-PGA in combination with cyclophosphamide in a murine melanoma model. Whereas cyclophosphamide alone directly triggered apoptosis of tumor cells in vitro, ${\gamma}$-PGA did not show cytotoxicity in tumor cells. Instead, it activated macrophages, as reflected by the upregulation of surface activation markers and the secretion of proinflammatory factors, such as nitric oxide and tumor necrosis factor ${\alpha}$. When the antitumor effects were examined in a mouse model, combined treatment with cyclophosphamide and ${\gamma}$-PGA markedly suppressed tumor growth and metastasis. Notably, ${\gamma}$-PGA treatment dramatically increased the NK cell population in lung tissues, coinciding with decreased metastasis and increased survival. These data collectively suggest that ${\gamma}$-PGA can act as an immunotherapeutic agent that exhibits a synergistic antitumor effect in combination with conventional chemotherapy.

• 한국응용과학기술학회지
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• 제24권2호
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• pp.196-204
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• 2007

The objective of this study was to determine the effect of dietary oils on the levels of the ${\gamma}-linolenic$ acid in chicken meat lipids. Three hundred ten five, 1-d old, male, Ross strain, broiler chicks were fed for 35 d to compare diets containing evening primrose oil(EPO) and hemp seed oil(HO) to a control diet. Fatty acid composition of lipid from chicken skin, thigh and breast muscle were determined at the end of the trial. The level of ${\gamma}-linolenic$ acid of lipids from chicken meat fed diets containing EPO or HO was significantly higher than that of the control group(p<0.05). The level of ${\gamma}-linolenic$ acid of lipids from chicken skin was highest in the group, which had been fed the EPO 0.85%, followed in order by EPO 0.7%, 0.5%, EPO mixed oil, HO and HO mixed oil. There was a significant difference in the level of ${\gamma}-linolenic$ acid of chicken skin between the control and treatment groups(p<0.05). The level of ${\gamma}-linolenic$ acid of lipids from chicken thigh muscle was also similar to skin, and significantly higher than that of the control group(p<0.05). The level of ${\gamma}-linolenic$ acid of lipids from chicken breast muscle was highest in the group, which had been fed the EPO 0.5%, followed in order by EPO 0.7%, 0.85%, HO 0.5% and HO mixed oil. There was a significant difference in the level of ${\gamma}-linolenic$ acid of chicken breast muscle between the control and treatment groups(p<0.05).

• 대한수학회지
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• 제46권3호
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• pp.657-673
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• 2009

The fixed point algebra $C^*(E)^{\gamma}$ of a gauge action $\gamma$ on a graph $C^*$-algebra $C^*(E)$ and its AF subalgebras $C^*(E)^{\gamma}_{\upsilon}$ associated to each vertex v do play an important role for the study of dynamical properties of $C^*(E)$. In this paper, we consider the stability of $C^*(E)^{\gamma}$ (an AF algebra is either stable or equipped with a (nonzero bounded) trace). It is known that $C^*(E)^{\gamma}$ is stably isomorphic to a graph $C^*$-algebra $C^*(E_{\mathbb{Z}}\;{\times}\;E)$ which we observe being stable. We first give an explicit isomorphism from $C^*(E)^{\gamma}$ to a full hereditary $C^*$-subalgebra of $C^*(E_{\mathbb{N}}\;{\times}\;E)({\subset}\;C^*(E_{\mathbb{Z}}\;{\times}\;E))$ and then show that $C^*(E_{\mathbb{N}}\;{\times}\;E)$ is stable whenever $C^*(E)^{\gamma}$ is so. Thus $C^*(E)^{\gamma}$ cannot be stable if $C^*(E_{\mathbb{N}}\;{\times}\;E)$ admits a trace. It is shown that this is the case if the vertex matrix of E has an eigenvector with an eigenvalue $\lambda$ > 1. The AF algebras $C^*(E)^{\gamma}_{\upsilon}$ are shown to be nonstable whenever E is irreducible. Several examples are discussed.

• 한국응용곤충학회지
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• 제33권4호
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• pp.263-269
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• 1994

궐련벌레(Lasioderma serricorne F)가 제품담배내 오염되었을때의 방제방법으로 감마선 이용법을 선전 방제효과를 조사하였다. Gelatin capsules에 공시충을 넣은 다음 감마선을 조사해 본 결과 0.8kGy이상의 선량에서 난태는 모두 살충되었고 용태나 성충때 및 유충태는 0~30%가 살충되었다. 몇가지 제품담배값내에 공시충을 함유한 gelatin capsules이 삽입된 궐련을 넣은후 감마선 조사시의 궐련벌레 충태별 방제효과도 동일한 결과를 얻었다. 감마선의 영향을 받은 궐련벌레의 성충 및 유충태를 인공먹이로 사육해 본 결과 차세대 개체군 증식이 확인되지 않았다. 감마선에 노출된 궐련벌레의 각 충태는 선량이 높아질수록 생존기간이 짧아졌으며 4령 유충이 처리 공시충중 가장 오래 생존하였다. 감마선에 노출된 제품담배의 고유향기나 맛은 선량 증가에도 영향을 받지 않았다. 감마선이 처리된 제품담배의 포갑지나 궐련지 및 은박지 등은 고유의 색도 또한 변화하지 않았다.