• 한국재료학회지
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• 제20권4호
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• pp.187-193
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• 2010

Chromium nitride (CrN) samples with two different layer structures (multilayer and single layer) were coated on bipolar plates of polymer electrolyte membrane fuel cells (PEMFC) using the reactive sputtering method. The effects with respect to layer structure on corrosion resistance and overall cell performance were investigated. A continuous and thin chromium nitride layer ($Cr_{0.48}\;N_{0.52}$) was formed on the surface of the SUS 316L when the nitrogen flow rate was 10 sccm. The electrochemical stability of the coated layers was examined using the potentiodynamic and potentiostatic methods in the simulated corrosive circumstances of the PEMFC under $80^{\circ}C$. Interfacial contact resistance (ICR) between the CrN coated sample and the gas diffusion layer was measured by using Wang's method. A single cell performance test was also conducted. The test results showed that CrN coated SUS316L with multilayer structure had excellent corrosion resistance compared to single layer structures and single cell performance results with $25\;cm^2$ in effective area also showed the same tendency. The difference of the electrochemical properties between the single and multilayer samples was attributed to the Cr interlayer layer, which improved the corrosion resistance. Because the coating layer was damaged by pinholes, the Cr layer prevented the penetration of corrosive media into the substrate. Therefore, the CrN with a multilayer structure is an effective coating method to increase the corrosion resistance and to decrease the ICR for metallic bipolar plates in PEMFC.

• Corrosion Science and Technology
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• 제9권3호
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• pp.129-136
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• 2010

The corrosion behaviors of 316L stainless steel were investigated in simulated anodic and cathodic environments for proton exchange membrane fuel cell (PEMFC) by using electrochemical measurement techniques. Interfacial contact resistance(ICR) between the stainless steel and gas diffusion layer(GDL) was also measured. The possibility of 316L was evaluated as a substitute material for the graphite bipolar plate of PEMFC. The value of ICR decreased with an increase in compaction stress(20 N/$cm^2$~220 N/$cm^2$) showing the higher values than the required value in PEMFC condition. Although 316L was spontaneously passivated in simulated cathodic environment, its passive state was unstable in simulated anodic environment. Potentiostatic and electrochemical impedance spectroscopy (EIS) measurement results showed that the corrosion resistance in cathodic condition was higher and more stable than that in anodic condition. Field emission scanning electron microscopy (FE-SEM), and inductively coupled plasma(ICP) were used to analyze the surface morphology and the metal ion concentration in electrolytes.

• 약학회지
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• 제40권2호
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• pp.230-237
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• 1996

The fractions of Epimedii Herba were examined for the immunological effects in ICR mice. Mice were divided into 4 groups and administered orally the fractions of Epimedii Herba for 10 days. The results of this study were summarized as following: (1) The fraction 1 (EtOAc layer) administered group as compared with control group significantly decreased spleen weight, Arthus reaction and hemagglutination (HA) titer but significantly increased circulating white blood cells (WBC). (2) The fraction 2 ($H_20$ layer) administered group as compared with control group significantly decreased liver weight, Arthus reaction and HA titer but significantly increased WBC. (3) The fraction 3 (ppt) administered group as compared with control group significantly increased liver weight, thymus weight rate, delayed type hypersensitivity, phagocytic activity and WBC. The results showed that Frs. 1 and 2 administered groups reduced humoral immune response but increased WBC, and that Fr. 3 administered group increased cell-mediated immune response, phagocytic activity and WBC.

• 한국표면공학회지
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• 제46권5호
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• pp.192-196
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• 2013

Stainless steels (AISI 316L) are carburized by Inductively coupled plasma using $CH_4$ and Ar gas. The ${\gamma}_c$ phase(S-phase) is formed on the surface of stainless steel after carburizing process. The XRD peak of carburized samples is shifted to lower diffracting angle due to lattice expansion. Overall, the thickness of ${\gamma}_c$ phase showed a linear dependence with respect to increasing temperature due to the faster rate of diffusion of carbon. However, at temperatures above 500, the thickness data deviated from the linear trend. It is expected that the deviation was caused from atomic diffusion as well as other reactions that occurred at high temperatures. The interfacial contact resistance (ICR) and corrosion resistance are measured in a simulated proton exchange membrane fuel cell (PEMFC) environment. The ICR value of the carburized samples decreased from 130 $m{\Omega}cm^2$ (AISI 316L) to about 20 $m{\Omega}cm^2$. The sample carburized at 200 showed the best corrosion current density (6 ${\mu}Acm^{-2}$).

• Radiation Oncology Journal
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• 제14권3호
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• pp.201-209
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• 1996

목적 : FIGO 병기 Ib 자궁경부편평상피암 환자에서 고선량율 강내치료를 이용한 방사선치료후 환해율, 5년 국소제어을, 5년 생존율 및 예후인자, 방사선 합병증을 분석하여 고선량율 강내치료의 효용성을 평가하고자 하였다. 그리고 심각한 후기 합병증 없이 만족스런 국소 제어율을 얻기 위한 외부방사선선량과 강내치료선량의 최적 선량배합을 알아보고자 하였다. 대상 및 방법 : 1979. 5 - 1990. 12월 까지 연세암센타 치료방사선과에서 자궁경부 편평상피암 FlGO 병기 Ib로 진단된후 근치적 목적하에 외부 및 강내치료를 받은 162명의 환자들을 대상으로 치료 결과를 후향적 분석하였다. 외부 방사선 치료는 LINAC 10MV X-ray를 이용해 180-200cGy/fr씩 4000-4600cGy14.5-5주를 전골반 부위에 시행하였근데, 일부환자에서 2000-4000 cGy에서 중앙차폐(midline block)를 시행하였다. 코발트 선원을 이용한 원격 조정 아프터 로딩 고선량율 강내치료를 A점에 1회당 300cGy씩 주 3회, 총 10-13회 (3000-3900 cGy)실시하여 A 점에 들어간 총방사선 조사량은 6420 - 9500cGy 으로 평균 8394 cGy 였다. 결과 : 방사선 치료후 완전 관해율은 $99.4\%$ 였다. 5년 전체생존율은 $91.1\%$이고, 5년 무병생존율은 $90.9\%$였다. 추적 관찰 기간동안 치료 실패 양상을 관찰해 보면 국소 실패만 보인 경우는 7명이었고 원격전이만 보인경우가 6명이었으며, 국소 및 원격전이가 모두 발생한 경우가 1예 있어서 국소제어 실괘율은 $4.9\%$(8/163), 원격전이율은 $4.3\%$(7/164)였다. 후기 합병증은 38명 ($23.5\%$)에서 발생하였초, 그 중 30병 직장 합병증으로 $18.5\%$ 후기 합병증 발생율을 보였고, 방광 합병증은 8명에서 발생하여 $4.9\%$ 후기 합병증 발생율을 보였다. 직장 합병증이 생긴 환자관에서 직장에 소사된 방사선량은 평균 7887 cGy 이었고, 합병증이 발생하지 않은 환자군의 평균조사량은 7488 cGy이었다. 결론 : 근치적 목적으로 외부 방사선 치료 및 고선량률 강내 치료는 FIGO병기 Ib 자궁경 부편평상피암을 치료하는데 매우 효과석이라 생각하였고, 외부방사선치료중 중앙차폐를 시행하여 A점 선량이 75Gy를 넘지 않게 방사선치료 설계를 하면 심각 합병증없이 좋은 치료성적을 얻을 수 있겠다.

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.275-278
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• 2013

• 대한의생명과학회지
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• 제22권3호
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• pp.75-82
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• 2016

The immune system and neuroendocrine systems are the two key components that maintain bodily homeostasis. Peripheral blood specimens can indicate abnormalities in a body, which often cause various threats to human health, including devastating autoimmune or metabolic diseases. To develop a treatment regimen for such diseases, experimental animal models are indispensable to researchers in academic fields. In this study, we examined the peripheral blood of 3 representative mouse strains (ICR, Balb/c, and C57Bl/6), which are widely used, to investigate whether there is a difference in reference range according to animal model. We performed hematological and chemistry analysis on individuals of both genders. The results of hematology analysis showed that the number of most types of blood cells was lower in ICR than in the other two strains. The results of chemical analysis revealed no specific pattern, but different patterns according to the individual indicator. Although the distinction between ICR and B6 was prominent, differences between Balb/c and B6 were also observed for several indicators. For some indicators, totally different patterns existed between females and males. Conclusively, this study provides the information that 3 experimentally representative mouse models have their own basal levels of blood components, suggesting the importance of a careful choice of a proper mouse model in research into immune or metabolic diseases, to exclude any biases.

• 사상체질의학회지
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• 제1권1호
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• pp.125-138
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• 1989

In order to investigate the effect of Row ginseng (Ra. G.; from $K{\acute{u}}msan$ province, Korea), White ginseng (W.G.; from $K{\acute{u}}msan$ province, Korea), and Red ginseng (Re. G.; form $K{\acute{u}}msan$ province, Korea) on immune response, the author used ICR mice having a body weight of about 20g as experimental animals dividing them into four groups-Saline, Ra. G, W.G., Re. G group. Delayed type hypersensitivity(DTH) and rosette forming cells(RFC) for cell-mediated immune response, hemagglutinin(HA) titers, hemolysin (HL) titers for humoral immune response were measured at 24 hours after challenge, The results were summarized as follows: 1) DTH was increased in all of the treated group as compared with the Saline group, with statistical significance(W.G.> Re. G. > Ra. G.). 2) RFC was increased in all of the treated group as compared with the Saline group, with statistical significance(W.G. > Re. G. > Ra. G.). 3) HA titer was increased in all of the treated group as compared with the Saline group, with statistical significance (Re. G.> W. G.> Ra. G.). 4) HL titer was increased in all of the treated group as compared with the Saline group, with statistical significance (Re. G. > W. G.> Ra. G.). Through the experimental study in ICR mice, these findings suggest that Raw ginseng, White ginseng and Red ginseng enhance both cell-mediated and humoral immune response with statistical significance.

• 혜화의학회지
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• 제8권1호
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• pp.131-146
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• 1999

To evaluate the antitumor activity of Kamisagoonjatang(KST), Kami-jihwangtang (KJT) and Kamigoonjajihwangtang(KKJT), studies were done experimentally. The results were obtained as follows: 1. In cytotoxicity against B16-F10, HT1080, SNU, and L1210, con-centration inhibiting cell growth up to below 50% of control was recognized at $10^{-3}g/ml$ of KKJT. 2. In cytotoxicity against A549, SK-OV-3, XF498 and HCT15, concentration inhibiting cell growth up to below 30% of control was over $400{\mu}g/ml$ of KKJT only and also over $200{\mu}g/ml$ against SK-MEL-2. 3. In Inhibitory effect on activity of DNA topoisomerase I, the $IC_{50}$ was shown $200-400{\mu}g/m{\ell}$, of KST, over $400{\mu}g/m{\ell}$ of KJT and $100-200{\mu}g/m{\ell}$ of KKJT. 4. The T/C% was 122.8 in KJT, 127.4 in KST and 158.4 in KKJ-Ttreated group in S-180 bearing ICR mice. 5. In hematological changes in S-180 bearing ICR mice, numbers of WBC were decreased significantly in KJT and KKJT treated groups as compared with control, whereas those of platelet were increased with no significance in all groups as compared with control. From above results it was concluded that KKJT could be usefully applied for the prevention and treatment of cancer.

• 한국동물학회지
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• 제34권3호
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• pp.389-393
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• 1991

To obtain monozygotic multiplets from 8-cell mouse embryos, we artificially constructed chimeric embryos by introducing one blastomere (donor) of 8-cell embryos of Fl hybrid (C57BL/6 X CBA) mice into 4-cell ICR mouse embryos (carrier) of which one blastomere had been previously removed with a micromanipulator. After 42 h of culture, the developmental frequency of chimeric embryos to normal morula and blastocyst was 95% (310/328). When chimeric embryos at morula or blastocvst stage were transferred to pseudopregnant mice,39%, (70/180) of them were born. Most of the offspring (56/70) were the carrier type in coat color, whereas only three of them were the donor type, of which ho were assumed to be derived from single 8-cell donor embryo. Because the two donor type mice Ivere the same sex and produced only the donor type offspring from a testcross, they are probably monozvgotic multiplets of 8-cell mouse embryos. However, since their internal chimerism was not able to be examined, it remains to be determined if their genetic constitutions are identical.