• The Journal of Korean Academy of Prosthodontics
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• v.43 no.2
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• pp.158-175
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• 2005

Statement of problem. Every effort has been continually made to obtain objectivity in measuring the longevity of fixed restorations, such as by establishing unified judgement standard for deciding success and adopting statistical method that analyzes the data of successful and failed cases at the same time. In Korea, however desired level of development has not to be made in this field yet. Purpose. This study, adopting California Dental Association (CDA) quality evaluation system, established objective standard for deciding success, and inferred the longevity of fixed restorations and their failure analysis through adopting Kaplan-Meier survival analysis. Material and method. In order to assess the longevity of flxed restorations serviced in Korea and causes of failure, a total of 1109 individuals (aged 15-74, 716 women and 393 men loaded with 2551 unit fixed restorations, and 1934 abutments) who lived in Kyung-In Province were examined and the findings were as follows : Results. 1. Length of service of fixed restorations serviced in Korea was 6.86$\pm$0.15 yr (mean), 5.5 yr (median), and the rate of success was 65.82% in 5 year survival, and 21.15% in 10 year survival. 2. When there was patient's need for replacing old prosthetics, longevity of fixed restorations was 7.51$\pm$0.27 yr (mean), 7 yr (median), and the rate of success was 61.08% in 5 year survival, and 17.57% in 10 year survival. 3. Longevity of fixed restorations was longest in the over-sixty age group(9.21$\pm$0.66) and that of the teen age group(3.39$\pm$0.28) was shortest (p<0.05). 4. Longevity of fixed restorations of women (7.38$\pm$0.18 years) was longer than that of men (6.00$\pm$0.26) (p<0.05). 5. As for the provider factor (such as unlicensed performers, university hospitals, and private clinic), there was no statistically significant difference in longevity of fixed restorations. 6. Defective margin (34.78%). periodontal disease (12.15%), periapical involvement (11.73%), was the most frequent causes of failure and poor esthetics group showed the longest life above all (p<0.05). Actual frequent causes of failure after removing old prosthetics were defective margin, periapical involvement, periodontal disease and uncemented restoration. In 75.67% of the cases, abutment state after removing old prosthetics was good enough for loading another prosthetics. 7. There was found to have statistically significant influence between longevity of single crown (6.35$\pm$0.20 yr) and that of 3 unit fixed restorations (7.60$\pm$0.30 y) (p<0.05). In each case the most frequent cause of failure was defective margin. 8. The number of cantilever pontic, pontic/abutment ratio, oral hygiene status were found to have no statistically significant influence on longevity of fixed restorations in all groups (p>0.05). 9. Longevity of fixed restorations made of non precious metal was longest (9.60$\pm$0.40 yr) semi precious and precious trailing behind(p<0.05). 10. Group function group (37.04%) and partial group function group (44.62%) were predominant in frequency but showed no correlation between them and among different types of occlusal plane and different types of occlusal surface (p>0.05). 11. Longevity of fixed restorations was longest in the centric interference group(9.35$\pm$0.62) (p<0.05) among different types of occlusal interference. Conclusion. We found that longevity of fixed restorations serviced in Korea is affected by age, gender and type of material, and that most frequent cause of failure is defective margin. In order to assess the accurate longevity of axed restorations, unified research design. overcoming inter-observer difference and establishing the objective research items are needed. Furthermore, it is thought that prospective approach through thorough study and regular follow-ups is needed just from the start of research. Nationwide detailed studies on length of service of fixed restorations manufactured in Korea are hoped to be conducted hereafter.

• Journal of Gastric Cancer
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• v.5 no.3 s.19
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• pp.191-199
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• 2005

Background: Though infections of Helicobacter pylori (H. pylori) are closely associated with activation of host angiogenesis, the underlying mechanisms, as well as the strategy for its prevention, have not been identified. Here, we investigated a causal role of H. pylori infection in angiogenesis of gastric mucosa and a potent inhibitory effect of a gastric proton pump inhibitor (PPI) on the gastropathy. Materials and Methods: A comparative analysis of CD 34 expression in tissues obtained from 20 H. pylori-associated gastritis and 18 H. pylori-negative gastritis patients was performed. Expression of $HIF-1{\alpha}$ and VEGF were tested by using RT-PCR. To evaluate the direct effect of H. pylori infection on differentiation of endothelial HUVEC cells, we carried out an in vitro angiogenesis assay. Results: H. pyfori-associated gastritis tissues showed significantly higher density of $CD34^+$ blood vessels than did H. pylori-negative gastritis tissues, and the levels were well correlated with expressions of $HIF-1{\alpha}$. Conditioned media from H. pylori-infected gastric mucosal cells stimulated a tubular formation of HUVEC cells. We also found a significant inhibitory effect of PPI, an agent frequently used for H. pylori eradication, on H. pylori-induced angiogenesis. This drug effectively inhibited the phosphorylation of MAP kinase ERK1/2, which is a principal signal for H. pylori-induced angiogenesis. Conclusion: The fact that PPls can down-regulate H. pylori-induced angiogenesis suggest that anti-angiogenic treatment using PPI may be a preventive approach for H. pylori-associated carcinogenesis.

• Journal of The Korean Association For Science Education
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• v.5 no.1
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• pp.49-61
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• 1985

In this study, I compared and analyzed the new and old secondary school science textbooks to find the charateristics of them and the differences between them. The results of the study are the following. Major concepts in the new textbook are almost similar to those in the old one. The-new textbook reinforces the functions of the introudction and checking the result of learning, and presents more and diverse learning materials and reduces the degree of learning difficulty by omitting the several abstract knowledges and mathematical formulas which can be understood through formal operational thinking. The results show that the new textbook is more effective in arousing student's interest and curiosity there fore it increases the efficiency of learning. But the new textbook is less suitable for inquiry because it is mainly composed of explanation and fact rather than experiment and observation. I think that this is the result from the actual approach to the real conditions of school when the curriculum was reformed and the new textbook was written.

• Korean Journal of Social Welfare
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• v.61 no.2
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• pp.325-348
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• 2009

This study intends to investigate the main and mediating effects which caregiving appraisal and positive reappraisal exert on quality of life (QOL) of primary family caregivers of cancer patient considering the relationship with social support. The processes of this study areas follows. First, the variables which research model were chosen on the basis of stress-appraisal-coping theory through reviews of the previous studies. Second, a survey was conducted upon 295 primary caregiver of patient with cancer at National Cancer Center. Collected data were analyzed by SPSS 12.0 and SEM (Structural Equation Modeling) method using AMOS 5.0. The summary of the result is as follows. First, the entire model including measurement and structural model shows sufficient fit index of CFI(.951), TLI(.940) and RMSEA(.062). Second, the results of analysis of direct effects among variables are as follows. The 'Social support' has statistically significant direct effect on the 'feeling of burden' and 'growth'. The 'feeling of burden' has statistically significant direct effect on the 'growth' and 'QOL-mental and physical'. The 'growth' has statistically significant direct effect on the 'QOL-mental'. Third, the results of analysis of mediating effects of the 'social support and QOL' and 'feeling of burden and QOL' are as follows. The effects of 'social support' on 'QOL-mental' are significantly mediated by the 'feeling of burden' and 'growth'. The effects of 'social support' on 'QOL-physical' are significantly mediated by the 'feeling of burden'. The effects of 'feeling of burden' on 'QOL-mental' are significantly mediated by 'growth'. Through this research, these implications in social work study and practice are found: (1) this study extended the scope of study in the caregiver's health area from negative sides into positive ones by using growth variables as positive reappraisalof caregiving in research model, which has not been tried on the Korean family caregivers of the cancer patient. (2) The effects of positive reappraisal on QOL-mental can provide a foundational necessity for social workers to help family caregivers find positive meaning in their caregiving experience. This approach of social work practice will improve QOL of family caregivers. (3) This study present a framework including social support, negative appraisal, positive reappraisal, and QOL variables available to social work practice and explaining affective relationships among these variables in various aspects.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.401-408
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• 1997

Background : Pulmonary sequestration is a rare congenital malformation, which is manifested by formation of nonfunctioning lung tissue lacking normal communication with the tracheobronchial tree. The preoperative diagnostic rate has been relatively low, and without consideration of pulmonary sequestration, unexpected bleeding from aberrant vessels may be a serious problem during the operation. The purpose of our study is to describe the clinical features of pulmonary sequestration based on a review of 15 cases treated by operation. Method : Fifteen patients with pulmonary sequestration who had undergone surgical treatment from 1991 through May 1996 at Yongdong Severance Hospital and Severance Hospital were reviewed retrospectively. Results : The mean age of the patients was 22.5 years (range 5~57), and male to female ratio was 9 : 6. Clinical presentations varied from recurrent respiratory infections such as fever, cough, and sputum or chest pain to no symptom. The chest simple X-rays showed multicystic shadow(10/15) and solid mass-like shadow(5/15). The chest CT scans, done in twelve cases, showed multicystic lesion with or without lung infiltration(8/12), solid mass-like lesion(4/12), The chest MRIs, done in three cases, revealed the aberrant arteries originating from descending aorta(2/3). Aortograms, done in four cases, showed the aberrant arteries originating from descending thoracic aorta(2/4), abdominal aorta(I/4), and intercostal artery(1/4). and the venous returns were via the pulmonary veins. Pulmonary sequestration was considered preoperatively in six patients of fifteen. Other preliminary diagnosis were lung tumor(3/15), lung abscess(21/15), bronchiectasis(2/15), and mediastinal tumor(2/15). In the operative findings, twelve cases were of intralobar type and three cases of extralobar type. The left lower lobe was most often affected(9/15) and one extralobar sequestration was in the pericardium. The aberrant arteries originated from descending thoracic aorta(6/15), abdominal aorta(1/15), internal thoracic arteries (2/15), intercostal artery(1/15), pericardiophrenic artery(1/15), but in four cases, the origins could not be defined. There was no mortality or complication postoperatively. Conclusion : In our study, preoperative diagnostic rate was relatively low, and clinical features were similar to previous reports. Preoperative vigorous diagnostic approach including aortography is strongly advocated not only for its diagnostic value, but also for accurate localization of the aberrant vessels, which is major concern to surgical procedure.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.323-330
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• 1996

Objective : Cavitary lesion in pulmonary tuberculosis sometimes makes problems in the course of treatment. Especially, retreatment cases tend to respond poorly to current antituberculosis agents. So, authors tried to render a guideline for clinical approach toward cavitary lesions in pulmonary tuberculosis. Methods : Retrospective analysis of 33 pulmonary tuberculosis patients with cavitary lesions was made. All the patients had got treatment at National Masan Tuberculosis Hospital from Jan. 1995 to Aug. 1995. Results: The ratio between male and female was 10:1. Age distribution was 69.7% in 3rd and 4th decades. The locations of cavitary lesion were 60.6% in right upper lung field and 36.4% in left upper lung field. In the extent of disease, there were 12 cases(36.4%) in moderate advanced and 21 cases in far advanced. Cavitary lesions were closed in 5 eases and remained in 28 eases. In the cases of closed cavity, it was happened within $10.6{\pm}4.72$ months after they took treatment, the size of cavity was $35.5{\pm}17.1$ in long diameter, $27.0{\pm}12.2$ in short diameter and $4.6{\pm}2.1\;mm$ in wall thickness. In the cases of remained cavity, the size of cavity was $31.9{\pm}12.3$ in long diameter, $21.0{\pm}9.8$ in short diameter and $5.04{\pm}2.0\;mm$ in wall thickness. In terms of negative conversion, it took $3.8{\pm}2.17$ months in the case of closed cavity but it was happened within 5 months for only 4 patients in the case of remained cavity. In the point of past medication history, there was none in closed cavities but there were none in 1 case, once in 3 cases, two times in 9 cases and more than three times in 13 cases among remained cavitary lesions. Conclusion : In the retreatment cases of pulmonary tuberculosis with cavitary lesions, they tend to respond poorly to current antituberculosis agents. So, if the lesions are localized, operative intervention may be a proper method as adjunctive treatment.

• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.45-56
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• 1998

Background: Lung cancer continues to increase worldwide. Also, the proportion of female patients incease and adenocarcinoma is the predominant histological type among lung cancer in many western countries. So, we studied these current trends of lung cancer by clinical approach of recent patients from our department Method: We conducted a retrospective analysis on 212 subjects who were diagnosed with lung cancer at the department of chest medicine in National Medical Center between January 1990 and July 1996. The contents of analysis were patient's profile, clinical manifestation, smoking habits, accuracy of diagnostic methods, histological cell type, staging and treatment, etc. Results: The results were as follows. 1) The ratio of male to female was 5.2 : 1. The peak incidence of age was 7th decade(35.4%). 2) Chief complaints were cough, dyspnea and chest pain, etc. The most common duration of symptoms before the first admission was less than 3 months(57.7%). On the other side, duration more than 1 year represented 6.5%. The early diagnosed patients has been increased from the 1980s. 3) Smokers among the total patients were 77.2%. The proportion of smokers in sqamous cell carcinoma, small cell carcinoma and adenocarcinoma were 88.4%, 85.7% and 55.7%, respectively. Smoking history and histological cell type were correlated in squamous and small cell carcinoma. 4) Squamous cell carcinoma is still the predominant histological type (44.8%), but, adenocarcinoma increased more than the previous study(30.7%). The other histological types were small cell carcinoma(17.0%) and large cell carcinoma(3.8%) in order of their proportions. 5) The accuracy of diagnostic methods were as follows: sputum cytology 75.3%, bronchoscopic biopsy 65.7%, lymph node aspiration cytology 95.8%, percutaneous lung aspiration cytology 94.6% and open lung biopsy 100%. The general accuracies of diagnostic methods were improved than previous studies. 6) Performance status scales on admission were relatively good. After diagnosis, chemotherapy and/or radiotherapy were undertaken in 69.3% of the patients, and only 7.5% of the patients were operated. Conclusion: In our study, squamous cell carcinoma is still the predominant histological cell type, but, adenocarcinoma continues to increase. Because adenocarcinoma is less correlated with smoking habits, further evaluation of other carcinogens than smoking is requested. Screening and early diagnosis of lung cancer is important for good performance status scales in spite of advanced stages. But, we think that the prevention, for example, stop smokings is more important as because of no perfect treatment for lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.64 no.3
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• pp.200-205
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• 2008

Background: Tumor angiogenesis plays an important role in tumor growth, maintenance and metastatic potential. Tumor tissue produces many types of angiogenic growth factors. Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) have both been implicated to have roles in tumor angiogenesis. In this study, the expression of tissue VEGF and bFGF from non-small cell lung cancer (NSCLC) patients were analyzed. Methods: We retrospectively investigated 35 patients with a histologically confirmed adenocarcinoma or squamous cell carcinoma of the lung, where the primary curative approach was surgery. An ELISA was employed to determine the expression of VEGF and bFGF in extracts prepared from 35 frozen tissue samples taken from the cancer patients. Results: VEGF and bFGF concentrations were significantly increased in lung cancer tissue as compared with control (non-cancerous) tissue. The VEGF concentration was significantly increased in T2 and T3 cancers as compared with T1 cancer. Expression of VEGF was increased in node-positive lung cancer tissue as compared with node-negative lung cancer tissue (p=0.06). VEGF and bFGF expression were not directly related to the stage of lung cancer and patient survival. Conclusion: Expression of VEGF and bFGF were increased in lung cancer tissue, and the expression of VEGF concentration in lung cancer tissue was more likely related with tumor size and the presence of a lymph node metastasis than the expression of bFGF. However, in this study, expression of both VEGF and bFGF in tissue were not associated with patient prognosis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.1
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• pp.54-59
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• 1999

This study was based on a series of 164 patients with zygomatic bone fracture treated at Department of Oral and Maxillofacial Surgery of Chonnam University Hospital from January 1992 to December 1996. The male-to-female ratio was 7:1. Their ages ranged from 8 to 78 years, with a median age of 35.6 years. The age frequency was highest in the second decade (30.5%), and third decade (23.8%), fifth decade (16.5%) in orders. The monthly distrbution of incidence showed October to be the month in which the greatest percentage occured (14.0%). The major cause of zygomatic bone fracture was alleged traffic accidents (53.7%). The incidence of concomitant facial bone fractures was 69,5%, and maxilla fracture (52.4%) was most frequently combined. The admission route was through emergency room (72.3%) and through outpatient department (26.8%). The incidence of associated injuries was 37.2%. The intraoral approach was the major method of treatment in zygomatic bone fracture (57.1%). The most frequent type of zygoma fracture was class IV (33.5%), and class III (25.6%) was next in order of frequency. Complications were enophthalmos (7.3%), facial asymmetry (6.7%), paresthesia (6.1%), and diplopia (2.4%) These results suggest that correct diagnosis and treatment of severity of fracture, concomitant fracture, and associated injuries are necessary, and co-operative treatment with medical department should be performed to reduce postoperative complication.

• Journal of the Korean Geographical Society
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• v.51 no.5
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• pp.613-632
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• 2016

The recent diagnosis of the Anthropocene challenges public understanding of nature as a pure and singular entity removed from society, as the diagnosis confirms the earth-changing force of humans. In geography, the nature-society divide has been critically interrogated long before the diagnosis of the Anthropocene, developing several ways of theorizing nature-society relations. This paper introduces a new frontier for such theoretical endeavors: more-than-human geography. Inspired by the material and performative turn in geography and the social sciences around the 2000s, more-than-human geographers have sought to re-engage with the livingness of the world in the study of nature-society relations. Drawing on actor-network theory, non-representational theory (NRT) and vitalism, they have developed innovative ways of thinking about and relating to nature through the key concepts of 'nonhuman agency' and 'affect'. While more-than-human geography has been extensively debated and developed in recent Euro-American scholarship on cultural and economic geography, it has so far received limited attention in Korean geographical studies on nature. This paper aims to address this gap by discussing the key concepts and seminal work of more-than-human geography. I first outline four theoretical strands through which nature-society relations are perceived in geography. I then offer an overview of more-than-human geography, discussing its theoretical foundations and considering ontologies, epistemologies, politics and ethics associated with nature-society relations. Then, I compare more-than-human geography with political ecology, which is the mainstream critical approach in contemporary environmental social sciences. I would argue that more-than-human geography further challenges and develops political ecology through its heightened attention to the affective capacity of nonhumans and the methodological ethos of doing a careful political ecology. I conclude by reflecting on the implications of more-than-human geography for Korean studies on nature-society relations.