• Biomedical Science Letters
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• v.5 no.1
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• pp.85-93
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• 1999

Nitric oxide (NO) plays an important role in immunologic defense, and influences upon the functioning of secretory tissues and cells. It also exhibits cytotoxic/cytostatic activity as one of major operating effectors of the cellular immunity system. We investigated the effects of serum on the cell damages and NO production in the mouse liver cell line BNL CL.2 to establish the role of NO. We observed that, when BNL CL.2 cells were cultured in serum-free medium, they were induced to cell damage by the stimulation of IFN-$\gamma$ alone or IFN-$\gamma$ plus LPS. Serum-starved cells showed large amount of nitrite accumulation and NO synthase (NOS) expression in response to IFN-$\gamma$ alone in dose- and time- dependent manners, but serum-supplied cells did not The production of NO was blocked by protein tyrosine kinase (PTK) inhibitors, genistein and herbimycin. These results suggest that the deprivation of serum in the BNL CL.2 cell culture medium might primed with the cells to produce NO when the cells are triggered by IFN-$\gamma$ and the involvement of PTK signal transduction pathway in the expression of NOS gene in murine hepatocytes.

• Biomedical Science Letters
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• v.3 no.2
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• pp.151-160
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• 1997

This study was planned to evaluate the urinary ascorbic acid as a new biological marker for the intoxication of cadmium, which could possibly be driven by its increased utilization and environmental pollution. In order to meet this goal, we have peformed measurement of urinary ascorbic acid concentration, histopathological examination of the kidney, and biochemical test for the liver function using cadmium-intoxicated rats by oral administration. The average concentrations of urinary ascorbic acid in the $CdCl_2$-treated rats were 214.0 mg/dl for 100 ppm group and 254.3 mg/dl for 200 ppm group during experimental period of 50 days. These levels are 24 and 28 times higher than one in the control group (9.0 mg/dl), respectively. Ultrastructural study showed the eosinophilic hyaline cast and focal effacement, fusion in the renal tubules, as well as loss of foot processes on the glomerular epithelial cells. These results suggested that cadmium may be responsible for renal glomerular injury. The blood levels of AST, ALT and LDH in the treated groups (199 IU/I, 88 IU/I, 1190 U/I for the 100 ppm group and 270 IU/I, 226 IU/I, 760 U/I for the 200 ppm group) were higher than ones in the control group(143 IU/I, 50 IU/I, 334 U/I). These results indicated the cadmium induced the damage of liver function. In conclusion, the administration of cadmium showed a remarkable increase of urinary ascorbic acid with renal and hepatic damage. Therefore, it is expected that measurement of urinary ascorbic acid would be an powerful method as a noninvasive biomarker for cadmium intoxication.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.341-349
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• 2013

In this study, the anti-oxidative and anti-obesity activities of two medicinal herb extracts, Tetrapanax papyriferus (TP) and Siegesbeckia pubescens (SP), were evaluated using DPPH radical scavenging activity assay, lipase enzyme inhibition assay, and the cell culture model system. Both methanol extracts of TP and SP showed DPPH radical scavenging activities dose-dependently, and the $IC_{50}$ of DPPH radical scavenging activities of the two medicinal herbs were 65.23 and 47.79 ${\mu}g/ml$, respectively. Furthermore, both extracts suppressed effectively lipase enzyme activity dose-dependently. Moreover, TP and SP extracts significantly suppressed adipocyte differentiation, lipid accumulation, triglyceride (TG) contents on 3T3-L1 preadipocytes in a dose-dependent manner without cytotoxicity. Their anti-obesity effect was modulated by cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding proteins ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$ and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) gene and protein expressions. Furthermore, TP and SP possessed a synergistic effect on anti-obesity activity. The identification of the active compounds that confer the anti-obesity activity of TP and SP might be needed.

• Journal of Life Science
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• v.27 no.11
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• pp.1376-1380
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• 2017

This study examined how the daily administration of dried CP roots affects body-weight gains of mice. An aqueous CP extract (1 g/kg of CP-W) was orally administered to mice on a daily basis for ten weeks, and the mice's body weights and food intakes were measured throughout the period. At the end of the ten-week treatment, murine blood samples were taken and hematological and serum biochemical parameters were examined. The mice's intra-abdominal organs were weighed at necropsy. The treatment of CP-W significantly suppressed the mice's body-weight gain by about 10%. There were no changes to the food intakes of and no observable abnormal clinical signs in any of the animals throughout the experimental period. There were no significant differences between the control and CP-W mice in regards to the hematological and serum biochemical parameters and the organ weights at necropsy. The results demonstrated that the daily administration of CP-W for ten weeks suppresses body-weight gain in mice and does not change mice's food intake or cause any noticeable toxic effects.

• Journal of the Korean Ceramic Society
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• v.41 no.11
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• pp.851-857
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• 2004

The stabilizing characteristics of heavy metals in the silicate glass (SD), borosilicate glass (BD), and leadsilicate glass (PD) containing Electric Arc furnace (EAF) dust were studied by the Toxic Characterization Leaching Procedure (TCLP) test. Also, the dependence of the amount of EAF dust upon structural changes of SD, BD, and PD glasses and the TCLP results were investigated by the XRD and FT-IR spectroscopy. In the XRD results, all of SD, BD, and PD specimens containing dust up to 30 wt% were amorphous without crystallizing. In the TCLP test, the concentration of heavy metals leached from the glasses increased with the amount of EAF dust added. The SD specimen series showed the lowest heavy metal leaching and the heavy metal leachate of the PD specimens were lower than those of the BD specimens. But, the Pb leaching from the PD specimens was the highest in the PD glass composition due to the high Pb content. The value of oxygen/network former ratio could be used to compare the chemical durability within the same glass series, but not proper to do between the different glass series. Adding the EAF dust to the SD mother glass, decreased the Si-O-Si symmetry and increased the non-bridging oxygen, which weakened the structure and decreased the chemical durability of glasses. In the BD series glasses, the addition of EAF dust caused the structural changes from tetra-borate group to di-borate group and the formation of the 2-dimensional layer structure of pyre- and ortho- borate, which decreased the chemical durability of glasses. It is concluded that SD series glass among the 3 kinds of glasses is the most effective to stabilize the heavy metals of EAF dust.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.3
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• pp.37-42
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• 2001

The concerns of the toxicity and health hazard of lead in solders have demanded the research to find suitable lead-free solder alloys. It was discussed that effect of the intermetallic formation and structure on the reliability of solder joints. In this study, lead-free solder alloys with compositions of Sn/3.5Ag/0.75Cu, Sn/2.0Ag/0.5Cu/2.0Bi were applied to the 48 $\mu$BGA packages. Also, the lead-free solder alloys compared with eutectic Sn/37Pb solder using shear test under various aging temperature. Common $\mu$BGA with solder components was aged at $130^{\circ}C$, $150^{\circ}C$ and $170^{\circ}C$. And the each temperature applied to 300, 600 and 900 hours. The thickness of the intermetallics was measured for each condition and the activation energy for their growth was computed. The fracture surfaces were analyzed using SEM (Scanning Electron Microscope) with EDS (Energy Dispersive Spectroscopy). These results for reliability of lead-free interconnections are discussed.

• Proceedings of the Safety Management and Science Conference
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• 1999.11a
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• pp.343-343
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• 1999

아크용접은 산업전반에 걸쳐 그 생산기반에 없어서는 안될 필수기술로써 자동차 및 조선, 항공우주산업에 이르기까지 경제기반에 미치는 파급효과가 매우 크다. 그러나 이 아크용접을 하게 되면 각종 가스와 미세입자로 이루어진 흄이 발생하게 되는데 이들은 작업자들의 건강에 많은 영향을 미치는 것으로 보고되어 있다. 용접흄에는 용접재료 및 용접공정에 따라 다양한 유해원소가 포함되어 있고 그 종류에 따라 인체에 미치는 잠재적 독성효과도 매우 광범위하다. 최근 국내에서는 용접사들 중에 용접흄에 포함된 중금속 중 Mn중독에 의한 파킨스씨병 환자들과 Cr중독에 의하여 콧속 연골에 구멍이 뚫리는 비중격천공(鼻中隔穿孔) 환자들이 직업병으로 판정 받아 산재요양이 승인된 사례가 있다. 이러한 계기로 인하여 용접사들의 용접기피 현상이 심화되고 작업환경에 대한 법적규제는 선진 외국뿐만 아니라 국내에서도 한층 엄격하게 강화되고 있는 실정이다. 따라서 이제는 작업자와 사용자 모두 용접흄에 대한 인식의 전환이 요구되는 때이며 여러 분야에서 이러한 용접흄에 대한 연구가 활발히 진행되어야 한다. 해외에서는 이미 용접흄에 대한 연구가 활발히 진행되어 왔으나 국내의 경우는 매우 미비한 상태이며 용접산업의 미래 영향력이나 필요성을 고려할 때 국내에서도 적극적인 관심을 가져야 할 부분으로 판단된다. 본 연구에서는 아크용접공정에서 발생하는 흄의 특정 중금속 성분이 인체에 치명적인 악영향을 미치는 것에 착안하여 여러 종류의 용접재료에서 발생되는 용접흄의 중금속 분포를 조사하여 비교하였다. 이것은 향후 용접재료별 및 용접공정별 발생되는 흄의 유해원소를 저감시킬 수 있고 또한 각종 유해원소의 노출기준 및 평가기준을 마련할 수 있는 기초data로써 도움이 되리라 사료된다.동, 공정중재고가 줄어드는 결과를 보였고, 가동률 수준이 높을수록 ORR 방법간의 차이가 크게 나타났다. 그리고 부하평준화 기능은 Order Release 정책의 유효성에 별 영향을 주지 않는 것으로 나타났다. 결론적으로, Order Release 방법은 우선순위규칙간의 성능차이를 줄이거나, 대체할 수 통제 기법이라기보다는 우선순위규칙을 보완하여 공정중재고와 작업현장에서의 리드타임, 리드타임의 편차를 줄여주는 역할을 한다고 볼 수 있다. 그리고, 계획시스템이 존재하여 계획오더가 일정기간간격으로 이송되는 환경에서 특히 유용하다는 결론을 얻었다. 알 수 있었다. 것인데, 제조업에서의 심각한 고비용, 저효율 문제 를 해결하기 위해 필수적으로 도입해야만 하는 실정이다. 또한 소비자의 다양한 요구로 인 하여 제품의 종류와 사양면에서 심한 변동을 보이는 시장 수요에, 신속한 정보처리로 대응 하는데도 크게 기여하고 있다. 이에 본 연구에서는, 자동차 Job Shop의 동기화 생산방식을 지원하는 동기화 생산시스템의 구축 모델을 제시하고자 한다.과로 여겨지며, 또한 혈청중의 ALT, ALP 및 LDH활성을 유의성있게 감소시키므로서 감잎 phenolic compounds가 에탄올에 의한 간세포 손상에 대한 해독 및 보호작용이 있는 것으로 사료된다.반적으로 홍삼 제조시 내공의 발생은 제조공정에서 나타나는 경우가 많으며, 내백의 경우는 홍삼으로 가공되면서 발생하는 경우가 있고, 인삼이 성장될 때 부분적인 영양상태의 불충분이나 기후 등에 따른 영향을 받을 수 있기 때문에 앞으로 이에 대한 많은 연구가 이루어져야할 것으로 판단된다.태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(min

• Korean Journal of Social Welfare
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• v.63 no.1
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• pp.187-215
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• 2011

This study examined the longitudinal relationship between depressive symptoms and alcohol use based on the tension reduction hypothesis and the intoxication hypothesis considering for path of depressive symptoms on alcohol use and vice versa simultaneously. And this study examined the effect of psychosocial behavior factors (i.e. smoking level, self-esteem, satisfaction with family relationships, and satisfaction with social relationships) on depressive symptoms and alcohol use. Using the data on the Korea Welfare Panel Study for the 1st, 2nd, and 3rd years, this study were estimated using the Latent Growth Curve Model which is helpful for examining differences between the two. The results are as follows: the initial level of alcohol use had a positive impact on the rate of change in depressive symptoms, thereby supporting the intoxication hypothesis. Second, self-esteem and satisfaction with family relationships act as variables with the biggest effect on the initial level and the rate of change in depressive symptoms, whereas other psychosocial behavior factors such as smoking level and satisfaction with social relationship exert the largest influence over the initial level and the rate of change in alcohol use. This study has implications in that it clarified the confused relationship mechanism between alcohol use and depressive symptoms the two. Based on the finding of the study, political and practical implications were discussed.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.100-109
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• 2013

This study aims to analyze 19 kinds of mineral contents in hair targeting 311 people in Seoul who suffer from hair loss. The results are as follows: 1. The average contents of all kinds of minerals were within the standards. 2. Sodium, potassium, and selenium were more detected in men than in women; calcium, magnesium, copper, and manganese were more detected in women than in men; toxic elements, mercury, antimony, and arsenic were more detected in men than in women, which was statistically significant. 3. As the age increased, potassium (p<.05), iron (p<.01), manganese (p<.05), chromium (p<.01), and mercury (P<0.01) increased gradually, which was statistically significant. In particular, the content of mercury exceeded its standard in those over fifty. 4. Selenium (p<.01), lead (p<.05), aluminum (p<.05), and arsenic (p<.01) were more detected in natural hair than in permanent or colored hair. Calcium (p<.001), magnesium (p<.001), and manganese (p<.01) were more detected in permanent or colored hair than in natural hair. They were all statistically significant.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.224-231
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• 1979

The safety of the sweetening component of stevia was studied by administrating it to the rats. The $LD_{50}$ determined by intraperitoneal injection was 3,400 mg/Kg as the stevia extract containing 50 % stevioside, i.e. $LD_{50}$ of stevioside was more than 1,700 mg/Kg. Oral administration of large quantities of the stevia extract for 56 days resulted in no effect on the growth of rats. The analyses of total blood (RBC, WBC, Hb and Hct), 17 blood serum components including total protein, glucose, cholesterol, GOT, and 11 items of findings on the liver tissues including nuclear deterioration of liver cells, proliferation of Kupffer cells, fibrosis of portal area showed no significant differences between control and treatments except lactate dehydrogenase activity after 56 day-oral administration of the extract. From the results obtained, it was supposed that the stevia extract/stevioside revealed no acute or sub-acute toxic effects on rats.