• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7419-7424
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• 2014

Gliomas are the most common type of primary brain tumors. The XRCC1 Arg194Trp variant affects the proliferating cell nuclear antigen(PCNA) binding region, which suggests that this mutation may contribute to gliomagenesis and a number of articles have examine the association between XRCC1 Arg194Trp and the susceptibility to glioma. However, the results were conflicting. Test of heterogeneity, sensitivity analysis, meta-analysis, and assessment of publication bias were all performed in our present meta-analysis, covering a total of 5,407 patients and 7,715 healthy persons. In the overall analysis the XRCC1 Arg194Trp polymorphism showed a significant association with glioma susceptibility in a recessive mode l(for TrpTrp vs ArgArg+ArgTrp: OR=1.918, 95%CI=1.575-2.336, $I^2$=2.3%). In addition, analysis of subgroups presented an increased risk in Asians and populations-based on hospitals. The results suggested that the XRCC1 Arg194Trp polymorphism is a genetic risk factor for glioma, especially in Asian population. To further evaluate gene-gene and gene-environment interactions on XRCC1 polymorphisms and glioma risk, thousands of subjects and tissue-specific biochemical characterizations are required.

• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8705-8708
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• 2014

Disrupted transforming growth factor-${\beta}$ (TGF-${\beta}$) signaling is involved in the development of various types of cancer and the TGF-${\beta}$ receptor II (TGFBR2) is a key mediator of TGF-${\beta}$ growth inhibitory signals. It is reported that the G-875A polymorphism in TGFBR2 is implicated in risk of various cancers. However, results for the association between this polymorphism and cancer remain conflicting. To derive a more precise estimation, a meta-analysis of 3,808 cases and 4,489 controls from nine published case-control studies was performed. Our analysis indicated that G-875A is associated with a trend of decreased cancer risk for allele A versus(vs.) allele G [odds ratio (OR) =0.64, 95% confidence intervals (CI): 0.55-0.74], as well as for both dominant model [(A/A+G/A) vs. G/G, OR=0.76, 95% CI: 0.64-0.90] and recessive model [A/A vs. (G/G+G/A), OR=0.74, 95% CI: 0.59-0.93). However, larger scale primary studies are required to further evaluate the interaction of TGFBR2 G-875A polymorphism and cancer risk in specific cancer subtypes.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3391-3396
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• 2014

Background: Vitamin D has been suggested as one of the critical factors for female reproductive health with protective activities against different cancers but there are conflicting facts regarding its role on breast cancer without any clear data on premenopausal cases. This study aimed to evaluate the role of vitamin D from dietary sources and sunlight exposure on the incidence of premenopausal breast cancer. Materials and Methods: We conducted a case control study on 60 newly diagnosed premenopausal breast cancer patients and 116 normal women who lived in Sabzevar and surrounding villages in Razavi, Khorasan, a rural and conservative area of Iran. Results: The mean concentrations of 25-OH vitamin D in cases and controls were $15.2{\pm}8.15$ vs $15.5{\pm}7/45ng/ml$, both well below normal values elsewhere. In fact 50% of analyzed individuals showed very severe or severe vitamin D deficiency and the rest (25%) were detected in suboptimal levels. Although the lack of vitamin D and calcium supplementation increased slightly the risk of premenopausal breast cancer (p=0.009, OR=1.115, CI 95%=1.049-1.187), higher prevalence of weekly egg consumption (86.66% vs 96.55%, p=0.023, OR=0.232, CI 95% 0.065-0.806) showed a slight protective role. The last but the most important risk factor was lack of sunlight exposure because the breast cancer patients had total body coverage from sun (p=0.007, OR=10.131, CI 98% 0.314-78.102). Conclusion: This study pointed out the role of vitamin D and other possible risk factors on the development and growth of breast tumors in this special geographical region. Although this study has revealed the interactions between hormonal and environmental factors in this province of Iran, understanding the deficiency pattern and its contribution to other lifestyle factors elsewhere is also necessary.

• BMB Reports
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• 제36권6호
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• pp.533-537
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• 2003

The nonsyndromic cleft lip and palate (NSCL/P) is a congenital deformity of multifactorial origin with a relatively high incidence in the oriental population. Various etiologic candidate genes have been reported with conflicting results, according to race and analysis methods. Recently, the ablation of the TGF-${\beta}3$ gene function induced cleft palates in experimental animals. Also, polymorphisms in the TGF-${\beta}3$ gene have been studied in different races; however, they have not been studied in Koreans. A novel A $\rightarrow$ G single nucleotide polymorphism (defined by the endonuclease SfaN1) was identified in intron 5 of TGF-${\beta}3$ (IVS5+104 A > G). It resulted in different genotypes, AA, AG, and GG. The objective of this study was to investigate the relationship between the SfaN1 polymorphism in TGF-${\beta}3$ and the risk of NSCL/P in the Korean population. The population of this study consisted of 28 NSCL/P patients and 41 healthy controls. The distribution of the SfaN1 genotypes was different between the cases and controls. The frequency of the G allele was significantly associated with the increased risk of NSCL/P [odds ratio (OR) = 15.92, 95% confidence interval (CI) = 6.3-41.0]. The risk for the disease increased as the G allele numbers increased (GA genotype: OR = 2.11, 95% CI = 0.38-11.68; GG genotype: OR = 110.2, 95% CI = 10.67 - 2783.29) in NSCL/P. A stratified study in patients revealed that the SfaN1 site IVS5+104A > G substitution was strongly associated with an increased risk of NSCL/P in males (p < 0.001), but not in females. In conclusion, the polymorphism of the SfaN1 site in TGF-${\beta}3$ was significantly different between the NSCL/P patients and the control. This may be a good screening marker for NSCL/P patients among Koreans.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.3117-3121
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• 2013

Objective: Previous epidemiologic studies demonstrated that obesity might associated with the risk of bladder cancer. However, many of the actual association findings remained conflicting. To better clarify and provide a comprehensive summary of the correlation between obesity and bladder cancer risk, we conducted a meta-analysis to summarize results of studies on the issue. Stratified analyses were also performed on potential variables and characteristics. Methods: Studies were identified by searching in PubMed and Wanfang databases, covering all the papers published from their inception to March 10, 2013. Summary relative risks (SRRs) with their corresponding 95% confidence intervals (CIs) were calculated by either random-effect or fixed-effect models. Results: A total of 11 cohort studies were included in our meta-analysis, which showed that obesity was associated with an increased risk for bladder cancer in all subjects (RR=1.10, 95% CI=1.06-1.16; p=0.215 for heterogeneity; $I^2$=24.0%). Among the 9 studies that controlled for cigarette smoking, the pooled RR was 1.09 (95% CI 1.01-1.17; p=0.131 for heterogeneity; $I^2$=35.9%). No significant publication bias was detected (p = 0.244 for Egger's regression asymmetry test). Conclusions: Our results support the conclusion that obesity is associated with the increased risk of bladder cancer. Further research is needed to generate a better understanding of the correlation and to provide more convincing evidence for clinical intervention in the prevention of bladder cancer.

• 산경연구논집
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• 제9권7호
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• pp.71-82
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• 2018

Purpose - This study examined the effects of intrinsic and extrinsic motivation on employee creativity. Past research has consistently shown that intrinsic motivation is positively related to creativity. Yet conflicting results have been reported about the relationship between extrinsic motivation and creativity. To explore the reason why extrinsic motivation can either help or hurt creativity, we examined the role of contingent rewards as a moderator and tested whether either tangible or intangible rewards contingent upon creative performance significantly impact the relationship between extrinsic motivation and creativity. Research design, data, and methodology - Survey data was collected from employees working for diverse organizations in Korea through online research firm. Only employees who reported their job or organization provided opportunities to use their creativity were allowed to continue the survey. Out of 305 initial responses collected, those with too much missing data were deleted, which finally left 278 responses for statistical analyses. To examine the validity of the measurements, confirmatory factor analysis was first conducted. Next, to test the hypothesized relationships, multiple hierarchical regression analyses were conducted. Results - As hypothesized, both intrinsic and extrinsic motivation had positive effects on creativity. It was shown that contingent rewards did not influence the positive relationship between intrinsic motivation and creativity, but did significantly moderate the relationship between extrinsic motivation and creativity in a way that tangible rewards strengthened the relationship while intangible rewards mitigated the same relationship. Conclusions - This research enhances our understanding on the relationship between motivation type, rewards, and creativity. Intrinsically motivated employees showed a high level of creativity regardless of whether rewards were expected or not. In contrast, extrinsically motivated employees showed more or less creative behavior depending on whether they were expected to have tangible or intangible rewards. As extrinsic motivation is typically associated with tangible rewards such as pay, promotion, etc., tangible rewards were seen to be more effective in promoting creative performance from extrinsically motivated employees than intangible rewards. Our findings make a significant theoretical contribution to reconcile prior inconsistent findings. Furthermore, they provide useful insights for managers and organizations into developing effective strategies for facilitating employee creativity.

• Asian Pacific Journal of Cancer Prevention
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• 제15권14호
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• pp.5889-5893
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• 2014

Over-expression of epidermal growth factor receptor (EGFR) has been identified as a common feature associated with clinical outcome in many types of cancer, including squamous cell carcinoma of the oesophagus (SCCO). However, the clinical importance of EGFR over-expression in SCCO remains unsettled as conflicting results exist. Therefore we carried out the present meta-analysis of published studies for clarification. A total of 13 studies including 1, 150 patients were enrolled. EGFR over-expression was positive in 722 of these cases. With EGFR over-expression, patients had higher depth of invasion, vascular invasion, and poor prognosis. However, expression had no relation with degree of differentiation, histological grade, lymph node metastasis, clinical stage or lymphatic invasion. EGFR over-expression is probably a valuable predictor for the T stage, vascular invasion and OS, and it could be used as a poor prognosis indicator for the esophageal SCC patients. Targeting therapy to EFGR should be considered to the combined treatment in SCCO.

• 한국문헌정보학회지
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• 제39권2호
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• pp.123-146
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• 2005

이 연구에서는 문서 자동분류에서 분류자질 선정과 가중치 할당을 위해서 일관된 전략을 채택하여 kNN 분류기의 성능을 향상시킬 수 있는 방안을 모색하였다. 문서 자동 분류에서 분류자질 선정 방식과 자질 가중치 할당 방식은 자동분류 알고리즘과 함께 분류성능을 좌우하는 중요한 요소이다. 기존 연구에서는 이 두 방식을 결정할 때 상반된 전략을 사용해왔다. 이 연구에서는 색인파일 저장공간과 실행시간에 따른 분류성능을 기준으로 분류자질 선정 결과를 평가해서 기존 연구와 다른 결과를 얻었다. 상호정보량과 같은 저빈도 자질 선호 기준이나 심지어는 역문헌빈도를 이용해서 분류 자질을 선정하는 것이 kNN 분류기의 분류 효과와 효율 면에서 바람직한 것으로 나타났다. 자질 선정기준으로 저빈도 자질 선호 척도를 자질 선정 및 자질 가중치 할당에 일관되게 이용한 결과 분류성능의 저하 없이 kNN 분류기의 처리 속도를 약 3배에서 5배정도 향상시킬 수 있었다.

• 과학기술학연구
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• 제6권2호
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• pp.103-129
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• 2006

최근 관심이 약화되고 있지만 정보격차는 정보사회 실현의 중요한 장애요인으로 지적되어 왔다. 정보격차에 대한 상반된 설명방식이라고 할 수 있는 낙관론과 비관론은 공통적으로 정보격차를 초래하는 객관적 조건에 초점을 맞추어 왔다. 그러나 접근 가능성은 객관적 조건뿐만 아니라 개인적 차원의 필요성에 대한 인식이나 의지와 같은 주관적 조건에 의해서도 달라질 수 있다는 사실은 경시되어 왔다. 인식이나 의지에 따르는 선택은 접속과 비접속을 결정하는 중요한 요인으로 작용할 수 있다. 미국의 경우 잠재적 이용자의 50% 이상이 스스로의 의지와 선택에 의해 인터넷을 사용하지 않는 것으로 알려져 있다. 우리나라의 경우에도 인터넷 사용자를 대상으로 한 조사에 따르면 '필요성을 느끼지 못해서'가 인터넷을 이용하지 않는 가장 중요한 이유로 나타났다. '이용할 시간이 없어서'라고 선택한 경우도 지속적으로 감소하고 있기는 하지만 상당한 비율을 차지하고 있으며 비 이용자들 중에서 차지하는 상대적 비중은 지속적으로 증가하고 있다. 선택에 의한 정보통신 기술의 비 이용자들을 정보격차의 범위에 포함시켜야 할 것인가의 문제가 있기는 하지만 정보사회로의 진행과정에서 선택에 의한 비 이용에 관심을 기울일 필요성은 분명한 것으로 보인다.

• 한국인구학
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• 제14권1호
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• pp.26-34
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• 1991

Migration studies that assume that decision making is done on an individual basis is overlooking the importance of the family factor. Considering that must people belong to families, it is more appropriate to view migration decision from the perspective of the family. This study analyzes the household migration decision whereby the alternatives are to stay, 10 undertake family migration or to undertake single migration of a member. In developing a conceptual model of household migration decision, it is assumed that the household's objective is to maximize household income which is a function of individual members' earnings. The benefits and costs of household migration and individual migration are identified and the household chooses the migration strategy that maximizes expected household income. When household members have conflicting earning prospects in the potential destination, the household considers single migration of the member with the best earning potentials. However, lone migration by a household member involves cost of family separation which is both monetary and psychic, and this study shows that lone migration is undertaken only when its net gains to the family are greater than the separation cost of the family. The major benefit of choosing single migration is the retention of home base in the place of origin which can serve as an insurance against the uncertainty of obtaining a job in the destination, the benefit that is unavailable in family migration. The conceptual analysis shows how a household's migration decision would depend on its members' economic roles and prospects in the destination. Besides the economic variables, social and life cycle variables of the family translate into separation costs and benefits of migration. This study indicates that one - earner family in low economic status but with good earning prospects and high separation costs is more likely to choose family migration over single migration.