• Journal of Preventive Medicine and Public Health
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• v.43 no.2
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• pp.185-192
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• 2010

Objectives: We conducted a meta-analysis to investigate the relationship between low external doses of ionizing radiation exposure and the risk of cancer mortality among nuclear power plant workers. Methods: We searched MEDLINE using key words related to low dose and cancer risk. The selected articles were restricted to those written in English from 1990 to January 2009. We excluded those studies with no fit to the selection criteria and we included the cited references in published articles to minimize publication bias. Through this process, a total of 11 epidemiologic studies were finally included. A publication bias was tested for using Egger's test. The homogeneity test was performed before the integration of each of the standardized mortality ratios (SMRs) and the result proved that the studies were heterogeneous. Results: We found significant decreased deaths from all cancers (SMR = 0.75, 95% CI = 0.62 - 0.90), all cancers excluding leukemia, solid cancer, mouth and pharynx, esophagus, stomach, rectum, liver and gallbladder, pancreas, lung, prostate, lymphopoietic and hematopoitic cancer. The findings of this meta-analysis were similar with those of the 15 Country Collaborative Study conducted by the International Agency for Research on Cancer. A publication bias was found only for liver and gallbladder cancer (p = 0.015). Heterogeneity was observed for all cancers, all cancers excluding leukemia, solid cancer, esophagus, colon and lung cancer. Conclusions: Our findings of low mortality for stomach, rectum, liver and gallbladder cancers may explained by the health worker effect. Yet further studies are needed to clarify the low SMR of cancers, for which there is no useful screening tool, in nuclear power plant workers.

• Journal of Chest Surgery
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• v.30 no.9
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• pp.941-944
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• 1997

Pulmonary infarction is rarely diagnosed with certainty except at postmortem examination. Part of this uncertainty is because of the inability to distinguish between hemorrhage, congestive a electasis, and necrosis clinically and radiographically. The pathogenesis of pulmonary infarction is poorly understood. It is dif%cult to induce pulmonary infarction in animals by ligation of the arterial supply to the lung. Many factors seem to be important in its pathogenesis, in addition to congestive heart failure, malignant tumor, thrombophlebitis, chronic obstructive lung disease, nephrotic syndrome, and postopeiative state. However, pulmonary infarction have not been reported in association with chest trauma. We report a case of pulmonary infarction associated with fractures of right clavicle and multiple ribs. A 45-year-old male had admitted due to right chest pain and dyspnea, which developed after right chest trauma occurred at about 3 weeks ago. He was treated at local clinics under the diagnosis of fractures of right clavicle and ribs until the admission. Chest CT disclosed a huge mass with central low density in right upper lobe, and small masses were also seen on both l ng fields. Open lung biopsy resulted in negativity for the malignancy. Clinical symptoms and radiological findings were not improved by conservative treatment. Right upper lobectomy was done eventually. The final diagnosis was pulmonary infarction. And, the patient has been well after operation.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.3
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• pp.223-229
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• 2017

When concrete is exposed to neutron rays for a long time, the concrete tends to become activated. If activated, it is classified as middle or low level radioactive waste. However, the great amount of the activated concrete is hard to dispose. In this study, low-activation cement was developed for decreasing the activated waste from shielding concrete around nuclear reactor. Furthermore, the manufactured low-activation was analyzed with activation nuclide Eu, Co. The low-activation cement showed great advantage for low-activation with detecting none of Eu and 3.75ppm of Co while ordinary portland cement showed 0.4~0.9ppm of Eu, 5.5~19.8ppm of Co content. As the results of physical properties of the low-activation cement, it is similar to type 1 ordinary portland cement and accords with type 4 low heat portland cement. Meanwhile, as for the chemical properties of the cement, it accords wite type 1 and 4 at the same time.

• Journal of Advanced Navigation Technology
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• v.20 no.5
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• pp.482-489
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• 2016

Detection of gamma ray can be available using optical fiber scintillator under radiation environment. It monitors the transfer energies of these ions by photodiodes and then convertes into currents. The module which converts those currents into voltages and processes signals is named fine current module TIA, and it is essentially important to convert currents into voltages with high linearity. We have studied and developed the TIA, improving converting linearity and minimizing noises and off-set voltages. Also, we have made efforts to develop precise and accurate current module in compliance with concerned requirements. First of all, we established developing theory, developed related circuits, and then made the current module. And, we confirmed its stability and linearity to be more excellent than any other equipment proposed by other references. We tested the developed fine current modules in the real radiation environment under authorized supervising, confirmed them to meet related requirements.

• Proceedings of the KAIS Fall Conference
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• 2012.05a
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• pp.72-75
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• 2012

본 연구는 2011년 8월 12일부터 8월 17일까지 일개 광역시에 대학병원에서 근무하는 안과인턴, 레지던트, 전문의, 방사선사, 안경사, 간호사를 대상으로 안과 PACS의 지능형 영상진단 및 치료지원 시스템 구축을 위한 사용자 요구도 조사를 실시하였다. 구성 대상은 의사 7명(38.9%), 의료기술직 4명(22.2%) 간호사 3명(16.7%), 기타 4명(22.2%)로 나타났다. 안과 PACS 도입 시 가장 중요한 부분으로 8(44.4%)명이 편리성이라고 하였고, 안과 PACS Viewer 중요분야는 9(50.0%)명이 편리한 기능이라고 하였다. 안과 PACS Viewer 필요분야에서 가장 필요한 분야는 14(77.8%)명이 망막분야라고 하였다. 이는 망막 검사의 대부분이 영상을 이용한 진단이 활용되어 있어 나타나 결과로 볼 수 있었다. 안과 PACS Viewer의 환경 관련 문항에서 검사 환자 리스트에서 가장 중요한 것은 생년월일, 부위 ,장비명이었으며, Annotation 및 사진 편집기능에서는 길이측정, 선 및 화살표 삽입, 글자입력으로 진료 및 치료에 직접적인 영향을 미치는 부분을 가장 중요한 환경 구성으로 응답하였다. 안과 PACS의 지능형 영상진단 및 치료에 대한 지원 시스템 구성은 기존 PACS에서 이루어져 있는 Viewer 형태의 UI 구성보다는 더 세밀하고 정확한 진단을 요하는 길이, marking, 장비의 특성, Color Palette 변화, Multi Modality Image Display를 요구하고 있다. 앞으로 방사선 분야의 기존 Viewer 형태의 PACS UI 구성보다는 각 분야에 맞는 PACS UI를 구축함으로써 더 정확하고 지능화된 영상 진단 및 치료 지원을 할 수 있어야 하겠다.

• The Journal of Internal Korean Medicine
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• v.25 no.3
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• pp.451-460
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• 2004

Objective : 황금의 유방암세포주에 대한 항암효과 및 기전에 대한 연구는 아직 미흡하며, 특히 에스트로젠리셉터를 가지지않은 유방암세포주인 MDA-MB-231에 대한 효과 및 기전에 대한 연구는 아직 발표된바 없어, 이에 대한 연구가 진행되었다. Methods : 인간 유방암세포주 MDA-MB-231 MTT assay를 이용 성장방해비율을 조사하였으며. FACS analysis를 이용 cell cycle analysis를 시행하였고, Western Blot Analysis 및 Annexin V analysis를 시행하였다. Results : MDA-MB-231에 대한 황금의 IC50는 180 ug/ml 이었으며 최대 세포성장억제효과는 $500{\mu}g/ml$로 한약재중 비교적 강한 세포독성을 보여 주었다. 유세포분석 에서 황금 $500{\mu}g/ml$의 농도를 72시간 투여한 경우 세포사멸(Sub Gl) 분율이 대조군의 1.7%에 비해 21%로 높아 현저한 용량의존적인 세포사멸현상을 보여주었으며, 세포사멸을 보다 명확히 규명할 수 있는 Annexin V analysis에서도 황금 $200{\mu}g/ml$농도일때 48시간에서 17%의 뚜렷한 세포사멸효과를 나타내었다. 한편 세포사멸촉진인자인 Bax, 세포사멸실행단백질인자인 caspase 3의 활성과 PARP의 분할은 세포사멸이 세포주기정지와 더불어 세포사멸의 과정에 p53이 관여함을 알 수 있다. 앞으로의 연구는 p53발현이 다른 세포주와 각 단백질의 억제제를 통해 인과적인 관련성을 즘 더 명확히 할 필요가 있어야 할 것으로 생각되어진다. Conclusion : 유방암의 예후에 있어 호르몬치료에 부적절함으로 인해 예후가 나쁜 에스트로젠리셉터 발현이 없는 유방암에 대해서도 황금이 탁월한 항암효과를 보여주고 있으며, 임상적으로 황금단독, 다른 항암약재와의 배합, 그리고 기존의 항암화학요법이나 방사선요법과의 병용투여를 통한 초기 및 진행된 유방암의 치료에 대한 새로운 접근의 실마리를 제공할 것으로 생각된다.

• Journal of the Korean Arthroscopy Society
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• v.15 no.2
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• pp.146-154
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• 2011

Injury of posterolateral corner is unusual, but it can cause disability due to severe instability and cartilage damage. However, the anatomical structures, diagnosis and treatment have not defined clearly yet. Posterolateral corner injury is regarded as the one of main factor to the results of failure in cruciate ligament reconstcution if it was undiagnosed and untreated. Diagnosis of postetolateral corner injury is consists of physical exam, radiographic finding, MRI, and arthroscopic findings. The treatment method of of postetolateral corner injury depends on the time and severity of injury. Anatomical reconstruction of posterolateral corner shows the better clinical outcome than non anatomical reconstructions, but the clinical results of long term follow up is still needed. Therefore, the aim of this article is to review the recent literatures and to organize diagnosis and treatment of posterolateral corner injury.

• Applied Chemistry for Engineering
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• v.28 no.2
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• pp.133-140
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• 2017

Increasing concerns on radioactive wastes have drawn much attention on the development of remediation technologies. Massive amounts of radioactive wastes generated from hospital and nuclear power plants were exposed to our environment. Although physicochemical removal methods were developed, an eco-friendly remediation method has not yet been demonstrated. Recently, an extremophilic bacterium has received much attention due to their extraordinary characteristics. Among them, Deinococcus radiodurans (D. radiodurans) strain was regarded as the best host organism for the removal of radioactive heavy metals and radionuclides, because of their superb characteristics like tolerance against the high level of radioactivity. In this article, we briefly introduced the extraordinary nature of D. radiodurans and also discussed the potential use of D. radiodurans strain for the removal of radioactive wastes.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.86-93
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• 2017

Purpose In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. Materials and Methods The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). Results The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. Conclusion The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus, those who have never been pregnant need to have a more active defensive conduct for the future possibility of pregnancy.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.1
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• pp.27-33
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• 2014

Purpose: The purpose of this study was to investigate the food impaction between implant prostheses and adjacent natural teeth. Materials and methods: For this study, 51 patients with food impaction were selected and investigated mobility, tightness of contact area, gingival index, plaque index, attachment loss, alveolar bone level, proximal caries, marginal ridge distance and occlusal relationships. Results: Food impaction was found in the upper teeth (60.7%) more than the lower teeth (39.2%). Food impaction was occurred on mesial side of implant prostheses (86.2%) more than distal side (13.7%). Food impaction was mostly found in loose or open contact area (94.2%). Food impaction was frequent on stepped relationship between implant and adjacent teeth. Conclusion: Treatment plan should include proper adjacent and antagonistic occlusal plane and occlusal surface, to prevent food impaction, and the plan should include less adjacent tooth mobility with proper tightness between implant prostheses and adjacent teeth.