• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.193-204
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• 1998

The single crystal of the $LiTaO_3$has large electro-optic effects, so it is applied to optical switch, acousto-optic deflector, and optical memory device as hologram using photorefractive effect. In this study, optic-grade undoped $LiTaO_3$and Fe:LiTaO$LiTaO_3$single crystals were grown by the Czochralski method and optical transmission and absorption spectrums were measured in the wavelength of UV-VIS range. The curie temperature was determined with DSC and by measuring capacitance for the grown undoped crystal and ceramic powder samples of various Li/Ta ratio. In case of having a 48.6 mol% $Li_2O$ as a starting Li/Ta ratio, the results of concentration variations were below 0.01 mol% $Li_2O$ all over the crystal, so it was confirmed that $LiTaO_3$single crystals were grown under congruent melting composition having optical homogeneity. The curie temperature of the Fe:$LiTaO_3$crystal was increased with increased with increased doped Fe concentrations;by the ratio of $7.5^{\circ}C$ increase per Fe 0.1 wt%. Also, the optical transmittance was about 78 %, which was sufficient for optical device.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1095-1101
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• 1996

From July 1983 to June 1995, 95 consecutive patients with mitral stenosis were treated surgically in the Department of Thoracic and Cardiovascular Surgery, Chonbuk national University Hospital, mitral valve replacement(MVR) in 62 patients and open mitral commissurotomy(OMC) in 33 patients. Mitral stenosis combined with coronary artery disease, with aortic valve disease, or wish mitral valvular Insufficiency, were excluded from this study. Surgical procedures for mitral stenosis were evaluated, according to complication, reoperation, mor- tality, nd functional change at mid- and long-term postoperative period. Cardiothoracic ratio in the MVR group was greater than the OMC group(0.59 $\pm$0.07 in MVR, 0.53 $\pm$0. 07 in OMC, p<0.05), but other variables(age, sex, MYHA functional classification, EKG finding, echocardiographic finding) did not show significant difference between two groups in the preoperative periods. Even though pathologic valvular lesion(Sellor's pathologic type m: 35 in MVR, 13 in OMC) and valvular calcification(35 in MVR, 11 in OMC) were severe in the MVR group(p=0.001) at intraoperative observation, OMC was possible in 11 patients(23.9%) among 46 patients with valvular calcification and in 13 patients(27.1 %) among 61 patients with Sellor's pathologic type IH . There was no significant difference in early and late mortality, actuarial survival(75% in MVR, 87.6% in OMC at 12 year), but early and late hemorrhagic, thromboembolic complications in the MVR group were greater than in the OMC. Functional changes in NYHA functional classification, EKG lEnding, cardiothoraclc ratio, and echocardiographic finding(EF, LVIDS, LWDd, LAD) did not differ between two groups in mid- and long-term postoperative periods. We conclude that our efforts for preservation of the native valve would be continued, because hemorrhagic and thromboembolic complications in the MVR were greater than in the OMC, and OMC was possible even in patients with severely stenotic and calcified mitral valve, although there was no sis-nificant difference in the functional change, mortality, and survival between the M VR and OMC.

• Journal of Chest Surgery
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• v.37 no.4
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• pp.322-327
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• 2004

Coronary artery bypass grafting on the beating heart is no longer a new methods for any cardiac surgeon. We evaluated the application of the off-pump coronary artery bypass procedure relative to safety and efficiency as measured by postoperative complication and operative mortality. Material and Method: We used our retrospective database to compare the patients having off-pump coronary surgery (n=100) with those having on-pump coronary surgery (n=100) between June, 1999 and August, 2002. Patients whom underwent associated valvular or aortic aneurysmal operation were excluded. Result: Neither groups showed any differences in the patient's risk factors and extent of coronary disease. Off-pump CABG group did not have significantly less mean operation time (295$\pm$73 min vs 323$\pm$83 min, p=ns) and mean hospital day (15.34$\pm$6.02 day vs 13.80$\pm$4.95 day, p=ns). However, off-pump CABG group had significantly shorter mean ventilation time (17.3$\pm$11.27 hour vs 24.98$\pm$16.1 hour, p＜0.05). No patients were converted to on-pump CABG in off-pump CABG. Intraoperative hemodynamic instability in off-pump CABG were 6 cases, of whom 2 cases were in lateral wall approach and 4 cases in right coronary anastomosis. Postoperative mortality was 1 case in off-pump CABG and 2 cases in on-pump CABG. Intra-aortic ballon pump (IABP) was applied in 1 case with off-pump CABG and in 2 cases with on-pump CABG. No patients presented postoperative cerebral infarction ＆ stroke in off-pump CABG but 2 patients in on-pump CABG. Postoperative arrhythmia presented in 4 cases with off-pump CABG and in 6 cases with on-pump CABG. Acute renal failure (ARF) was complicated in 3 cases with off-pump CABG and in 2 cases with on-pump CABG. Conclusion: This study documented the immediate safety and efficiency of the off-pump CABG procedure.

• Journal of Chest Surgery
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• v.37 no.7
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• pp.547-552
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• 2004

Recently, autologous bone marrow cell transplantation (CTx) for angiogenesis and myogenesis in ischemic myocardium has been extensively investigated to improve heart functions. This study was designed to evaluate the effects of CTx with off-pump coronary artery bypass grafting (OPCAB) in patients who were not feasible for complete revascularization. Material and Method: Four male patients underwent CTx and OPCAB simultaneously. Bone marrow was aspirated from iliac bone. Mean 1.5 ${\times}$ 10$^{9}$ mononuclear cells including mean 6.7 ${\times}$ 10$^{6}$ CD34 + cells and 3.7 ${\times}$ 10$^{6}$ AC133 + cells were obtained and concentrated with 10 cc. These cells were transplanted into non-graftable ischemic myocardium after OPCAB. The heart function of all patients were evaluated using the MIBI scan, echocardiogram and MRI preoperatively. The effects of CTx was evaluated using MIBI scan and echocardiogram at 1 month postoperatively. Result: An average of 2 grafts were bypassed to left anterior descending artery territory. Other territories were transplanted with isolated mononuclear cell. All patients had uncomplicated postoperative course. After 1 month follow up, there were improvement in symptom, ejection fraction (from 49% to 55%) on echocardiogram and myocardial perfusion on MIBI scan in all patients. Conclusion: These preliminary data showed improvement of heart function and myocardial perfusion and also showed the feasibility and safety of combined therapy with OPCAB and CTx in ischemic myocardium. However, the effectiveness of CTx alone cannot be readily assessed. Further randomized, controlled studies are required to evaluate the effectiveness of CTx alone.

• Journal of Korean Home Economics Education Association
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• v.21 no.2
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• pp.109-125
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• 2009

The purpose of this study was to analyze research trends in clothing and textiles education focused on primary and secondary school education. Among the reviewed articles published between 1989 and 2008 in four journals including The Journal of Korean Home Economics Education, The Journal of Korean Association of Practical Arts Education, Journal of the Society of Clothing and Textiles, and Journal of the Korean Home Economics Association, 175 articles were related to clothing and textiles education. The most popular research field was teaching contents followed by teaching-learning method and teaching material, while clothing selection and self-expression, the general focus on home economics education and making clothing and household utensils were the popular research topics. In terms of research methods, about three quarters of articles used survey methods followed by experiment method and documentary studies. The rapid increase in research on clothing selection and self-expression and the decrease in articles on making clothing and household utensils seem to have had an influence on the government revision of The $7^{th}$ Curriculum.

• Journal of Forest and Environmental Science
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• v.19 no.1
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• pp.85-98
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• 2003

The articles, published in the Journal of Korean Forestry from Number 1(1962) to Number 6, Volume 91(2002), were surveyed and investigated for the research trend analysis about resource-plants for special use or purpose, i. e., edible plants, medicinal plants, feed resource, landscape plants, fiber plants, industrial usuage, and bee plants. If the purpose or subject matter of the research was construction or furniture timber production, mushrooms and/or pulp and paper, such research was not included in this study. These articles were classified again depending on the content of research into 14 categories: habitat environment, ecology, physiology, propagation, silviculture (tending and culture), genetics and breeding, identification, insect and disease control, animal-related research, component analysis, vegetation survey, biotechnology, management, and review. Among the total 1.434 articles published, 396 ones (27.6%) were related with plants for special use or purpose. Vegetation survey was 60 (15.2%): physiology 56(14.1%) : genetics and breeding 56(14.1%): propagation 53(13.4%): and ecology 37(9.3%). Siviculture research field included 11 articles (2.8%), which indicates that the management of resource-plants is so far from economic income as seen in the low number of management research filed articles, i. e., only 6 reports (1.5%) Korean white pine was most popular for research and included 42 articles: Robinia pseudoacacia 23: Castanea crenata 14: and ginkgo tree 14. Research related with these species had focused mainly on propagation, physiology, genetics and breeding, ecology and pest control. Based on this survey and analysis, the followings are suggested: 1. More research is required on forest herbaceous plants. 2. Cooperative research work with other industrial and/or scientific area is recommendable for commercialization including medicine, cosmetics, and food etc. 3. Research on resource-plant conservation, which includes biology, social education and policy, should be supported for next generation. 4. Mutual correspondence and information exchange about the research results between researchers and institutes is more necessary than now.

• The Korean Journal of Financial Management
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• v.10 no.1
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• pp.249-280
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• 1993

Recent financial theory views insurance policies as financial instruments that are traded in markets and whose prices reflect the forces of supply and demand. This article analyzes individual's insurance purchasing behavior along with capital market investment activities, which will provide a more realistic look at the tradeoff between insurance and investment in the individual's budget constraint. It is shown that the financial economic concept of insurance cost should reflect the opportunity cost of insurance premium. The author demonstrates the importance of riskless and risky financial assets in reaching an equilibrium insurance premium. In addition, the paper also investigates how the investment income could affect the four established theorems on traditional insurance literature. At the present time in Korea, the price deregulation is being debated as the most important current issue in insurance industry. In view of the results of this paper, insurance companies should recognize investment income in pricing their coverage if insurance prices are deregulated. Otherwise. price competition may force insurance companies to restrict coverage or to leave the market.

• Korean Journal of Biological Psychiatry
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• v.15 no.4
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• pp.275-287
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• 2008

Depression and coronary artery disease are both highly prevalent diseases. Many previous studies suggest that depression is a common comorbid condition in patients with coronary artery disease and has a significant negative impact on the onset, course, and prognosis of coronary artery disease. However, the exact mechanisms that underlie the association between these two diseases remain unclear. Pathophysiologic mechanisms that may explain the effect of depression on coronary artery disease include hypercoagulability, hypothalamus-pituitary-adrenal axis and autonomic nervous system dysregulation, altered inflammatory response. On the contrary, pathophysiologic mechanisms in coronary artery disease that affect depression are less well known. It is also suggested that both diseases may share a common genetic vulnerability. The authors reviewed the literature on the pathophysiologic relationships of depression and coronary heart disease.

• Clinical and Experimental Pediatrics
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• v.50 no.5
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• pp.462-468
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• 2007

Purpose : The purpose of this study was to analyze the changes of the late potential of Signal- averaged electrocardiography (SAECG) and Electrocardiography (ECG) parameters during follow up of those who had taken surgical repair of Tetralogy of Fallot (TOF). Methods : Nine patients who had taken surgical repair of TOF since 1985 checked SAECG and standard 12 leads ECG twice in 1999 and 2005 in Kyungpook national university hospital. We evaluated changes of QRS duration, QT interval and JT interval, QRS dispersion, QT dispersion and JT dispersion of standard 12 leads ECG and Filtered QRS (f-QRS), High frequency low amplitude potential (HFLA), Root mean square in terminal 40 ms (RMS) and Mean voltage in terminal 40 ms (MV) of SAECG between in 1999 and 2005. Results : There were significant decrease of JT dispersion ($101.11{\pm}50.11$ vs $71.11{\pm}22.61ms$, P< 0.05) and significant increase of HFLA ($24.67{\pm}13.19$ vs $32.89{\pm}14.21ms$, P<0.05). But there were no significant changes in other parameters. Conclusion : In repaired TOF patients, we evaluated ECG and SAECG to detect possible late complications such as tricuspid regurgitation, right ventricular enlargement, ventricualar arrythmia and sudden death. And there were significant changes of ECG and SAECG in some parameters (JT dispersion, HFLA). But to see the relationships between the changes of these parameters and the long term prognosis, we need to check more patients and longer follow-up.

• The Korean Journal of Nuclear Medicine
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• v.34 no.3
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• pp.243-251
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• 2000

Purpose: This prospective study was performed to evaluate the usefulness of preoperative radioimmunoscintigraphy and intraoperative scintimetric examination (radioimmunoguided surgery: RIGS) using $^{99m}Tc-anti-CEA\;F(ab')_2$ fragment. Materials and Methods: Nineteen patients with rectal cancer underwent preoperative whole body planar scintigraphy at 4 hours after injection of $^{99m}Tc-anti-CEA\;F(ab')_2$ fragment and SPECT imaging at 18 hours. Surgical operation was performed at 24 hours after injection. During laparotomy, radioactivities from intraabdominal viscera were measured by gamma probe. The radioactivities from excised tumor and lymph nodes were also measured and compared with pathology. Results: All nineteen patients were confirmed to have adenocarcinomas in the rectum. Twenty-seven of 97 excised lymph node groups had metastasis and 2 patients had liver metastasis in pathology Preoperative radioimmunoscintigraphy detected primary tumors in 11 patients (sensitivity 55%) and it could not detect any lymph nodes or liver metastasis. All patients showed high radioactivity in the kidneys, liver, spleen, and major vessels in intraoperative measurement by gamma probe, and tumor activity was not discriminated from background activity However, radioactivity from excised tumor was higher than normal rectum (T/B ratio; $3.47{\pm}2.25$). When excised lymph node activity/background activity ratio >1.5 was considered as positive criteria of metastasis, sensitivity, specificity, positive and negative predictive values were 78.6%, 73.9%, 55.0% and 89.5%, respectively. Conclusion: Radioimmunoscintigraphy using $^{99m}Tc-anti-CEA\;F(ab')_2$ has no additional value for preoperative staging and use of early RIGS using $^{99m}Tc-anti-CEA\;F(ab')_2$ is inappropriate. For early RIGS using $^{99m}Tc$ labeled antibodies in rectal cancer patients, further development of more specific antibodies and methods to reduce background activity are needed.