• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.535-545
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• 2005

Environmental survey from some abandoned metal mine areas was undertaken on to assess the risk of adverse health effects on human exposure to arsenic influenced by past Au-Ag mining activities. Elevated levels of As were found in tailings from the studied mine areas. This high concentration may have a impact on soils and waters around the tailing piles. In order to perform the human risk assessment, chemical analysis data of soils, rice grains and waters fur As have been used. The HQ values fer As via the rice grain and groundwater consumption were significantly higher compared with other exposure pathways in all metal mine areas. However, there were minimal soil and water dermal contact risks. The resulting Hl values of As from the Dongil, Okdong and Hwacheon mine areas were higher than 5.0, and their toxic risk due to drinking water and rice grain was strong in these mine areas. The cancer risk of being exposed to As by the rice grain route from the Dongil, Okdong and Hwacheon mine areas was $5.2\times10^{-4},\;6.0\times10^{-4}\;and\;8.1\times10^{-4}$, respectively. The As cancer risk via the exposure pathway of drinking water from these mine areas exceeded the acceptable risk of 1 in 10,000 fer regulatory purposes. Thus, the daily intakes of groundwater and rice grain by the local residents from the Dongil, Okdong and Hwacheon mine areas can pose a potential health threat if exposed by long-term arsenic exposure.

• Journal of Chest Surgery
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• v.35 no.11
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• pp.826-830
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• 2002

Prosthetic valve thrombosis(PVT) may be a life-threatening complication requiring prompt intervention. This is a case report of thrombolytic therapy for thrombosis of prosthetic mitral valve. A 47 year-old male admitted to the emergency room for abrupt onset of dyspnea. He had undergone mitral valve replacement(On-Ⅹ valve, 29mm) for mitral stenosis 8 months ago. The patient's international normalized ratio(INR) on admission was 1.09. The mechanical clicks were muffled and rales were heard in both lung fields. A transesophageal echocardiography(TEE) revealed prosthetic valve thrombosis with increased transvalvular pressure gradient(34 mmHg). The patient's condition needed to intubation for mechanical ventilation due to hemodynamic compromise, however his wife and relatives refused the surgical intervention due to financial problems. The patient was transferred to the cardiac care unit and we decided to perform thrombolytic therapy. A bolus of 1,500,000 IU of urokinase was given, followed by a drip of 1,500,000 IU for 1 hour. The patient did not improved hemodynamically; therefore, we gave 100 mg of tissue plasminogen activator(t-PA) for over 2 hours. During that time mechanical clicks were audible and hemodynamics of the patient improved progressively. A TEE showed disappearance of thrombus and decreased pressure gradient(1.7 mmHg) after 6 hours of thrombolytic therapy. The patient was recovered without any neurologic sequale and was discharged with administration of warfarin.

• Journal of Chest Surgery
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• v.38 no.11 s.256
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• pp.733-738
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• 2005

Background: The possibility of incomplete revascularization and development of flow competition after revascularization of the borderline lesion made the hybrid strategy as an option for complete revascularization. Material and Method: From January f998 to July 2004, 25 $(3.2\%)$ patients underwent hybrid revascularization among 782 total OPCAB procedures. Clinical results and angiographic patencies were evalulated. Percutaneous coronary intervention (PCI) was peformed before CABG in 8 patients and after CABG in 47 patients. Result: The causes of PCIs before CABG were to achieve complete revascularization with minimally invasive surgery (n=7) and emergent PCI for culprit lesion (n=1). The indications of PCIs after CABG were high possibility of flow competition in the borderline lesion of right coronary artery territory (n=8), diffuse atheromatous lesion preventing anastomosis of graft (n=5), severe calcified ascending aorta with no more arterial grafi available (n=3), and intramyocardial coronary lesion (n=1). Mean number of distal anastomoses was $2.3\pm1.0$. Mean number of lesions treated by PCI was $1.2\pm0.4$. There was no operative or procedure-related mortality. PCI-related complication was periprocedural myocardial infarction in one patient, and complications related to CABG were transient atrial fibrillation (n=5), perioperative myocardial infarction (n=1), and transient renal dysfunction (n=1). Early postoperative coronary angiography $(1.8{pm}1.6days)$ revealed $100\%$ patency rate of grafts (57/57). The stenosis occurred in one patient performed PCI before CABG, which was successfully treated with re-ballooning. During midterm follow-up (mean; $25{\pm}26$ months), 1 patient died of congestive heart failure. All survivors (n=24) accomplished follow-up coronary angiographics, which showed .all grafts (56/57) were patent except one string sign. In-stent restenosis was developed in 2 patients who received bare metal stents. Conclusion: In selected patients, complete revascularization was achieved with low risk by taking the hybrid strategy.

• Tuberculosis and Respiratory Diseases
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• v.41 no.4
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• pp.372-378
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• 1994

Background: Pressure support ventilation(PSV) is a new form of mechanical ventilatory support that assists spontaneous inspiraory effort of an intubated patient with a clinician-selected amount of positive airway pressure. Low level pressure support during inspiration can overcome the resistive component of inspiratory work imposed by an endotracheal tube. However the clinical efficacy of PSV as a weaning method has not been established yet. Object: The aim of study was to evaluate the efficacy of PSV when it is added to intermittent mandatory ventilation(IMV) in facilitating weaning precess compaired to IMV mode alone. Method: When the subject patients became clinically stable with their arterial blood gas analysis in acceptable range, they underwent weaning process either by IMV alone or by IMV plus PSV. The level of pressure support was held constant throught the weaning period. For the patients who required mechanical ventilation for less than 72 hr, 2h weaning trial was performed with IMV rate starting from 6/min. For the patients who required mechanical ventilation more than 72 hr, 7 hr weaning trial was performed with IMV rate starting from 8/min. For the patients who failed three consecutive trials of weaning, retrial of weaning was attempted over 3 days with IMV rate starting from 8/min. Clinical characteristics, APACHE II score and nutritional status were compared. For all patients, heart rate, mean blood pressure and respiratory rate were mornitored for 48 hrs after weaning trial started. Results: The total number of weaning trial was 37 in 23 patients(18 by IMV, 19 by IMV+PSV). Total ventilation time, APACHE II score and nutritional status were not statistically different between the two groups. The weaning success rate were not statistically different(38.3% by IMV, 42.1% by IMV+PSV) and the changes of mean blood pressure, heart rate, respiratory rate during first 48 hours were not different between the two groups. Conclusion: Low level PSV when added to IMV for weaning trial does not seem to improve the success rate of weaning from mechanical ventilation. PSV at 10cm $H_2O$ did not induce significant physiologic changes during weaning process.

• Journal of Distribution Research
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• v.5 no.2
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• pp.49-68
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• 2001

In this chapter, we summarize the results on the optimal location selection and present limitation and direction of research. In order to reach the objective, this study selected and tested the interaction model which obtains the value of co-ordinates on location selection through the optimization technique. This study used the original variables in the model, but the results indicated that there is difference in reality. In order to overcome this difference, this study peformed market survey and found the new variables (first data such as price, quality and assortment of goods, and the second data such as aggregate area, and area of shop, and the number of cars in the parking lot). Then this study determined an optimal variable by empirical analysis which compares an actual value of market share in 1988 with the market share yielded in the model. However, this study found the market share in each variables does not reflect a reality due to an assumption of λ-value in the model. In order to improve this, this study performed a sensitivity analysis which adds the λ value from 1.0 to 2.9 marginally. The analyzed result indicated the highest significance with the market share ratio in 1998 at λ of 1.0. Applying the weighted value to a variable from each of the first data and second data yielded the results that more variables from the first data coincided with the realistic rank on sales. Although this study have some limits and improvements, if a marketer uses this extended model, more significant results will be produced.

• Clinical and Experimental Pediatrics
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• v.50 no.7
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• pp.649-654
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• 2007

Purpose : The objective of this study was to clarify the presentation, associated preceding illness, pathologic organisms, treatment and outcome of deep neck abscess in children according to age and location. Methods : We retrospectively reviewed the in-patient charts of children treated at our hospital for deep neck abscess. Thirty-five such patients were identified as having been treated from March 1990 to December 2005. Results : A total of 35 were enrolled in our study: 25 boys and 10 girls. Their ages ranged from 11 months to 15 years. Presenting symptoms included mass, fever, irritability, trismus and dysphagia. The most commonly known associated preceding illness was viral upper respiratory infection (53%). The most common site of infection was the submandibular space (37%). Bacteria was identified in 16 patients. The most common pathogen was Staphylococcus aureus. Thirteen (37%) children recovered from the infection with conservative treatment and twenty-four (68%) children received surgical drainage. The duration of hospitalization was longer in the group who underwent surgery than in the group who were managed with conservative treatment. No complication occurred. Conclusion : Unexplained torticollis, trismus or irritability in children were suggestive of deep neck abscess. Our results demonstrate that deep neck abscesses in children is respond well to conservative treatment if diagnosed early.

• Pediatric Infection and Vaccine
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• v.8 no.1
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• pp.94-100
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• 2001

Purpose : Enterovirus is a common cause of aseptic meningitis and nonspecific febrile illness in young children. During the summer and fall months, enterovirus-infected young children are frequently admitted and evaluated to rule out bacterial sepsis and/or meningitis. The purpose of this study was to evaluate the relationship between nonpolio enterovirus infection and febrile illness in infants under 3 months of age during the summer, fall months by using a stool culture to identify the presence of enterovirus. Methods : Patients included febrile infants under 3 months of age admitted to Masan Fatima Hospital for sepsis evaluation from May 1999 to September 1999. Cultures were performed from stool and Cerebrospinal fluid samples and then were tested for enterovirus infection. Viral isolation and serotype identification were performed by cell culture and immunofluorescent testing. Enteroviruses not typed by immunofluorescent testing were confirmed by reverse transcription-polymerase chain reaction. Results : A total of 44 febrile infants were enrolled; of those, 20(45%) were positive for enterovirus. Two enterovirus culture-positive infants had concomitant urinary tract infection and one had Kawasaki disease. All infants infected with an enterovirus recovered without complications. Serotype of 20 enteroviruses were isolated from stool, 3 of echovirus type 9, 1 of echovirus type 11, 1 Coxsachievirus type B4, 15 of untyped enteroviruses. One untyped enterovirus was isolated in the CSF. Conclusion : Nonpolio enterovirus infections are associated with nonspecific febrile illnesses in infants under 3 months of age.

• Pediatric Infection and Vaccine
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• v.5 no.1
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• pp.69-78
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• 1998

Purpose : The risk of severe tuberculous disease such as meningitis or miliary tuberculosis increases as younger is the child at the time of infection. Therefore, the early diagnosis and prompt treatment is mandatory for infants with tuberculosis. This study was undertaken to describe the epidemiology, clinical and radiographic manifestations, and response to therapy in infants with tuberculous disease. Methods : Medical records of 29 infants with tuberculosis diagnosed at the Seoul National University Children's Hospital from July, 1985, to April, 1997, were reviewed, retrospectively. A case of tuberculosis was confirmed if M. tuberculosis was isolated from any body site or if there was histologic proof of tuberculosis. Otherwise, the diagnoses were individualized considering history of contact with contagious adult case, clinical manifestations, chest X-ray findings, result of a Mantoux test reaction with 5 tuberculin unit of PPD, and the response to therapy. Results : The mean age at diagnosis was $7.00{\pm}2.65$ months (range, 3 to 12 months). Twelve cases had isolated pulmonary diseases, and the rest had pulmonary disease and meningitis, 5 cases; pulmonary disease and cervical lymphadenitis, 3; isolated meningitis, 3; and miliary tuberculosis, 6. Source case was identified in 19 cases, 7 of which were detected with retrograde manner. Twenty seven of 29 were symptomatic at their initial visit. The presenting symptoms were mainly respiratory or neurologic, and respiratory difficulty was accompanied in 7 cases. Physical examination revealed wheezing in 7 cases and decreased breath sounds in 9. Hepatomegaly or hepatosplenomegaly were frequent. Chest radiographs showed lung parenchymal disease with hilar lymphadenopathy in 18 cases, and focal or generalized emphysematous change in 7 cases. Conclusion : Most of the infants with tuberculosis are symptomatic at diagnosis, and many of infants with intrathoracic tuberculosis presented with symptoms of bronchial obstruction. When tuberculosis is suspected in an infant, the adult source case should be vigorously investigated to aid in diagnosis and for the prevention of further transmission of tuberculous disease. Almost half of infant tuberculosis are preventable if prophylaxis were given when adult cases were diagnosed.

• Journal of Chest Surgery
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• v.36 no.8
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• pp.559-565
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• 2003

By improving the flow pattern in Fontan circuit, total cavopulmonary connection (TCPC) could result in a better outcome than atriopulmonary connection Fontan operation. For the patients with impaired hemodynamics after atriopulmonary Fontan connection, conversion to TCPC can be expected to bring hemodynamic and functional improvement. We studied the results of the revision of the previous Fontan connection to TCPC in patients with failed Fontan circulation. Material and method: From October1979 to June 2002, eight patients who had failed Fontan circulation, underwent revision of previous Fontan operation to TCPC at Yonsei University Hospital. Intracardiac anomalies of the patients were tricuspid atresia (n=4) and other functional single ventricles (n=4). Mean age at TCPC conversion was 14.0$\pm$7.0 years (range, 4.6~26.2 years) and median interval between initial Fontan operation and TCPC was 7.5 years (range, 2.4~14.3 years). All patients had various degree of symptoms and signs of right heart failure. NYHA functional class was 111 or IV in six patients. Paroxysmal atrial fibrillation (n:f), cyanosis (n=2), intraatrial thrombi (n=2), and protein losing enteropathy (PLE) (n=3) were also combined. The previous Fontan operation was revised to extracardiac conduit placement (n=7) and intraatrial lateral tunnel (n=1). Result: There was no operative death. Major morbidities included deep sternal infection (n=1), prolonged pleural effusion over two weeks (n=1), and temporary junctional lachyarrhythrnia (n=1). Postoperative central venous Pressure was lower than the preoperative value (17.9$\pm$3.5 vs. 14.9$\pm$1.0, p=0.049). Follow-up was complete in all patients and extended to 50,1 months (mean, 30.3$\pm$ 12.8 months). There was no late death. All patients were in NYHA class 1 or 11. Paroxysmal supraventricular tachycardia developed in a patient who underwent conversion to intraatrial lateral tunnel procedure, PLE was recurred in two patients among three patients who had had PLE before the convertsion. There was no newly developed PLE. Conclusion: Hemodynamic and functional improvement could be expected for the patients with Fontan circulatory failure after atriopulmonary connection by revision of their previous circulation to TCPC. The conversion could be performed with low risk of morbidity and mortality.

• Tuberculosis and Respiratory Diseases
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• v.60 no.1
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• pp.72-75
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• 2006

Background : This report reviews our experience with persistent air leaks in the peumothorax that were not considered candidates for surgical treatment in order to evaluate the efficacy and risks of the OK-432 plus autoblood or OK-432 pleurodesis. Material & Methods : From March 2004 to July 2005, 8 consecutive patients who had an air leak in the pneumothorax over 5 days and had been treated with OK-432 plus autoblood or OK-432 pleurodesis. The patients were not considered candidates for surgical treatments because the chest CT findings revealed severe chronic lung disease with multiple bullae and/or bullous changes. A prolonged air leak with/without dead space was treated with either OK-432 plus autoblood or OK-432 pleurodesis. The efficacy and side effects of OK-432 pleurodesis were assessed by determining the duration of the air leak, the number of pleurodesis, the patients' symptoms, measurements of the white blood cell count and the c-reactive protein level. Results : All of eight patients were male and the mean age was $72.4{\pm}8.5$. The mean number of pleurodesis was $1.9{\pm}1.1$ and the mean duration of the air leak was $4.6{\pm}4.6days$ after pleurodesis. Side effects after pleurodesis were encountered in 7 patients, which included a chilling sensation in 7 cases, chest pain in 5 cases, headache in 3 cases, local heat sensation in 2 cases, and fever in 1 case. Leukocytosis was observed in 6 patients, and the mean of WBC count and CRP were $14500{\pm}2100$ and $21.9{\pm}11.4mg/dL$, respectively. Conclusion : Either OK-432 plus autoblood or OK-432 pleurodesis has acceptable side effects, and can be considered a treatment option for persistent air leaks in the pneumothorax that are not candidates for surgical treatment.