• Korean Journal of Materials Research
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• v.20 no.4
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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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• v.9 no.3
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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.

• YAKHAK HOEJI
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• v.40 no.2
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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.

• Journal of the Korean institute of surface engineering
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• v.46 no.5
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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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• v.14 no.3
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• pp.201-209
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• 1996

Purpose : To assess the efficacy of high dose rate - intracavitary radio-therapy (HDR-ICR) in the radiotherapy of FIGO stage IB squamous cell carcinoma of uterine cervix and to determine the optimum dose combination scheme of external radiotherapy and ICR to achieve acceptable local control without severe complication. Materials and Methods : One hundred and sixty two patients with FIGO stage Ib squamous cell carcinoma of uterine cervix who received definitive radiotherapy between May 1979 and December 1990 were retrospectively analyzed. All the patients received external radiotherapy combined with HDR-ICR. External dose of 40-46 Gy in 4.5-5 weeks was given to whole pelvis(median 45 Gy) and ICR dose of 30-39 Gy in 10-13 times was given to the point A. Midline shielding was done after 20-45 Gy of external radiotherapy(median 40 Gy) Summation of external dose Plus ICR dose to the point A range were 64.20-95.00 Gy. and mean was 83.94 Gy. We analyzed the local control rate, survival rate, and late complication rate. Rusults : Initial complete response rate was $99.4\%$ for all patients. Overall 5-year survival rate was $91.1\%$ and 5-year disease free survival rate was $90.9\%$. Local failure rate was $4.9\%$ and distant failure rate was $4.3\%$. Tumor size was the only significant prognostic factor. When tumor size greater than 3cm, 5-rear survival rate was $92.6\%$ and less than 3cm, that was $79.6\%$. Late complication rate was $23.5\%$ with $18.5\%$ of rectal complication and $4.9\%$ of bladder complication. Mean rectal dose summation of external midline dose plus ICR rectal point dose was lower in the patients without rectal complication(74.88 Gr) than those with rectal complication (78.87 Gy). Complication rate was increased with low rate of improvement of survival rate when summation of external midline dose plus point A or point R dose by ICR was greater than 70-75 Gy. Conclusion : The definitive radiation therapy using high dose rate ICR in FIGO stage IB uterine cervical cancer is effective treatment modality with good local control and survival rate without severe complication.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.275-278
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• 2013

• Biomedical Science Letters
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• v.22 no.3
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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.

• Journal of Sasang Constitutional Medicine
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• v.1 no.1
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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.

• Journal of Haehwa Medicine
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• v.8 no.1
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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.

• The Korean Journal of Zoology
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• v.34 no.3
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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.