• International Journal of Contents
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• v.8 no.3
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• pp.100-104
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• 2012

In this paper, a unit cell for low pass filter design by using composite right and left-handed transmission line in conductor-backed coplanar waveguide is proposed. The characteristics of the unit cell are analyzed in order to design a low pass filter in small sizes. By changing the sizes of the unit cell, the parameters of right-handed and left-handed immittance components are changed and the desired characteristics of the unit cell are achieved. The equivalent circuit of the unit cell is extracted and analyzed either. As a result, the simulation results of the unit cell and the equivalent circuit are almost identified. The movement and energy distributions of electromagnetic field are shown to confirm the property of the unit cell. In the end, a low pass filter is demonstrated by cascading three proposed unit cells, which shows cutoff frequency of 1.53GHz and deep attenuation from 2.23GHz to 4.49GHz lower than -50dB.

• Journal of the korean veterinary medical association
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• v.26 no.1
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• pp.38-42
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• 1990

The effect of Aloe vera administration(500mg/kg, P.O.) for 21 days on the total white blood cell, packed cell volume, hemoglobin, total protein, serum glutamic pyruvic transaminase and sorbitol dehydrogenase values in cobalt-60 gamma irradiated rats was s

• Journal of the korean veterinary medical association
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• v.17 no.3
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• pp.47-60
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• 1981

Lymphocytes that secrete antibodies can be made immortal by fusing them with myeloma tumor cells (cell fusion) and cloning the hybrids (hybridomas). Each clone is a long-term source of substantial quantities of a single highly specific antibody (monoclona

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1691-1695
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• 2013

Objective: To evaluate the association between tea consumption and the risk of renal cell carcinoma. Methods: We searched PubMed, Web of Science and Scopus between 1970 and November 2012. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Results: Twelve epidemiological studies (ten case-control studies and two cohort studies) were included in the final analysis. In a meta-analysis of all included studies, when compared with the lowest level of tea consumption, the overall relative risk (RR) of renal cell carcinoma for the highest level of tea consumption was 1.03 (95% confidence interval [CI] 0.89-1.21). In subgroup meta-analyses by study design, there was no significant association between tea consumption and renal cell carcinoma risk in ten case-control studies using adjusted data (RR=1.08, 95% CI 0.84-1.40). Furthermore, there was no significant association in two cohort studies using adjusted data (RR=0.95, 95% CI 0.81-1.12). Conclusion: Our findings do not support the conclusion that tea consumption is related to decreased risk of renal cell carcinoma. Further prospective cohort studies are required.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.5
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• pp.518-524
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• 2008

Chromosome 18q alteration plays a key role in colorectal tumorigenesis, and loss of heterozygosity at 18q is associated with a poor prognosis in colon cancer. DCC(Deleted in Colorectal Cancer) is a putative tumor- suppressor gene at 18q21 that encodes a transmembrane protein with structural similarity to neural cell adhesion molecule that is involved in both epithelial and neuronal cell differentiation. DCC is implicated in regulation of cell growth, survival and proliferation. Thus, tumor progression in squamous cell carcinoma, stomach cancer, colorectal cancer correlates with downregulation of DCC expression. The mechanism for DCC suppression is associated with hypermethylation of the DCC gene promoter region. Hence, the goal of this study is to identify the promoter methylation responsible for the down-regulation of DCC expression in oral squamous cell carcinoma. 12 of tissue specimens for the study are excised and gathered from 12 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find expression of DCC in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1. In the DCC gene RT-PCR analysis, 5(41.6%) of 12 specimens of oral squamous cell carcinoma did not expressed DCC gene. 2. In the promoter methylation specific PCR analysis, 5(41.6%) of 12 specimens showed promoter methylation of DCC gene. 3. In the immunohistochemical staining of poor differentiated and invasive oral squamous cell carcinoma, loss of DCC expression was observed. These findings suggest that methylation of the DCC gene may play a role in loss of gene expression in invasive oral squamous cell carcinoma.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.6
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• pp.519-525
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• 2001

The oral cavity has frequent contacts with many carcinogenic compounds and its soft tissue is continuously stimulated by numerous dental factors. We have examined the detailed dental factors and its correlation with oral squamous cell carcinoma, and denture-wearing effects to analyze the effect of the dental factors on the genesis of oral squamous cell carcinoma. We have studied clinical contributing factors and the dental factors in the genesis of oral squamous cell carcinoma when the effects of smoking and drinking are controlled. The study cases are 100 patients(75 males and 25 females) who were diagnosed histo-pathologically as squamous cell carcinoma at the Yonsei Medical Center. The control group was 154 patients who have no systemic malignant tumors. The effects of 6 dental factors were analyzed in this study. They were divided into the smoking group, the non smoking group, the drinking group, and the non-smoking group. The effects of dental factors were analyzed in each group. In this study, we have drawn some conclusions on the relationship between the dental factors and oral squamous cell carcinoma using $x^2$-test. 1. The repaired teeth have statistical significance on the genesis of squamous cell carcinoma. This is probably due to the combining effects of past poor oral hygiene and continuous stimulation due to poor prosthesis. 2. There is statistical significance of the lost teeth in the smoking group, and the repaired teeth and the degree of alveolar bone resorption had statistical significance in the non-smoking group. 3. Smoking and drinking by-itself have no statistical significance in the genesis of oral squamous cell carcinoma. However, in combination, they have statistical significance. In this study, dental factors had a synergistic effect with smoking and drinking. Together with avoidance of smoking and drinking, appropriate restoration and oral hygiene control are most important factors in the preventive aspects of the oral squamous cell carcinoma.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.2
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• pp.154-163
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• 2000

Growth factors and the receptors play an important role in the regulation of the growth and development of mammalian cells. In particular, epidermal growth factor is a polypeptide with potent mitogenic activity that stimulates proliferation of various normal and neoplastic cells through the interaction with its specific receptor(EGFR). EGFR has been described as a parameter of poor prognosis in many human neoplasms such as breast, bladder, and vulvar cancers. The objectives of this study are the evaluation of the expression of EGFR and cell cycle analysis in the head and neck squamous cell carcinomas(SCC), and the evaluation of the correlation between clinico-patholgic features and expression of EGFR and S-phase fraction. 37 head and neck squamous cell carcinoma specimens were evaluated for expression of EGFR by Western blot analysis and S-phase fraction by cell cycle analysis using the flow cytometry. The obtained results were as follows : 1. The expressions of EGFR were observed in 20 specimens(54%) among 37 head and neck SCC specimens. In case of oral SCC, 15 specimens(56%) out of 27 specimens were observed, and in case of nasopharyngeal SCC 5 specimens(50%) out of 10 specimens. 2. There was no correlation between clinical features(location, stage) of head and neck SCC and expression of EGFR (p>0.05). 3. There was a significant correlation between histo-pathological differentiation of head and neck SCC and expression of EGFR (p<0.02). 4. There was a significant correlation between expression of EGFR and S-phase fraction of cell cycle in the head and neck SCC (p<0.05). The above results suggest that expression of EGFR and S-phase fraction of cell cycle are adjunctive prognostic marker in the head and neck squamous cell carcinomas.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.386-394
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• 2008

The study of subjects were 8 persons. The study measured VO2max of each person and substituted METs at exercise intensity of both VO2max 50% and VO2max 70% in accordance with energy consumption formula to set exercise time at energy consumption of both 300kcal and 600kcal. And, the study substituted inclination and rate at exercise intensity that was measured at preliminary test. T, B, NK cell varied depending upon aerobic exercise to have no significant difference of exercise intensity at relative ratio of T, B, NK lymphocyte of all of lymphocytes and to have significant difference of Expenditures Calorie (p<.01) and interaction (p<.05) by T cell and Expenditures Calorie (p<.01) by B cell and Expenditures Calorie (p<.001) and interaction (p<.05) by NK cell.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.1
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• pp.7-12
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• 2005

Purpose: CKD-602, a newly developed water-soluble campthotecin analogue, is a anticancer agent which act as a DNA topoisomerase I inhibitor. CKD-602 is known as more potent and tolerable agent. The main purposes of this study were to measure the cytotoxic effect of CKD-602 on the oral cancer cell lines and to evaluate the apoptotic aspect of dead cells. Materials and Methods: To determine the cytotoxic effect of CKD-602 on the oral cancer cell lines in comparison with various cell lines, such as lung cancer and colon cancer cell lines, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay was performed. And apoptosis was analyzed using fluorescence-activated cell sorting(FACS) system. Results: CKD-602 decreased the viability of malignant cells in a dose dependent manner and in a time dependent manner. CKD-602 showed excellent cytotoxicity to the oral cancer cell lines. Also, apoptotic portion was increased in a dose dependent manner. Conclusion: These findings indicated that CKD-602 induced apoptotic cell death in the various cell lines including oral cancer cell lines. From the results, it was suggested that CKD-602 would be a potential therapeutic agent for the oral cancer. More successive researches on the anticancer effect of CKD-602 should be performed.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.67-75
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• 2006

Background: Cytotoxic function of killer cells is inhibited by specific recognition of class I MHC molecules on target cells by inhibitory killer Ig-like receptors (KIR) expressed on NK cells and some cytotoxic T cells. The inhibitory effect of KIR is accomplished by recruitment of SH2-containing protein tyrosine phosphatase (SHP) to the phosphotyrosine residues in the cytoplasmic tail. Methods: By in vitro coprecipitation experiments and transfection analysis, we investigated the association of KIR with an adaptor protein Shc in Jurkat T cells. Results: The cytoplasmic tail of KIR appeared to associate with an adaptor protein Shc in Jurkat T celilysates. Similar in vitro experiments showed that phosphorylated KIR cytoplasmic tail bound SHP-1 and Shc in Jurkat T cell lysates. The association of KIR with Shc was further confirmed by transfection analysis in 293T cells. Interestingly, however, Shc appeared to be replaced by SHP-2 upon engagement of KIR in 293T cells. Conclusion: Our data indicate that KIR associate with an adaptor protein Shc in Jurkat T cells, and suggest that KIR might have an additional role which is mediated by this adaptor protein.