• Korean Business Review
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• v.11
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• pp.241-253
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• 1998

One form of the anomalies of stock price changes as reaction to earnings information is believed to be caused by the so-called earnings fixation, which is the overreaction of stock prices to earnings. According to the Sloan (1996) study, stock price changes are positively associated with earnings at the time of earnings releases, but the association becomes negative after that, as the early overreaction is corrected. However, the problem in his study is to use cash flows computed by adjusting earnings with appropriate income statement and balance sheet items. As Bahnson et al. (1996) show, these cash flows substantially deviate from SFAS No. 95 cash flows and the sample used in this study is found to be subject to this substantial measurement error. Therefore, the result of Sloan might be driven by this error and the reexamination of earnings fixation is warranted. The results are generally consistent with those in Sloan. First, earnings is positively associated with stock price changes at the time of earnings releases, but the association becomes negative after that. Second, cash flows show a weak association with stock price changes at the time of earnings releases, but the association become stronger thereafter. Third, when seperated from cash flows, accruals have an incremental explanation about stock price changes beyond that of cash flows, accruals have a negative association later on. This finding is consistent with stock price overreaction to accruals, even when more cleaner cash flow data are used.

• Journal of Korea Water Resources Association
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• v.35 no.1
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• pp.97-108
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• 2002

The use of land at the time of investigation of groundwater quality in the rapidly urbanized Bu-chon city is classified into 5 categories based on the change process of land use. The difference in groundwater quality according to the land use and its usage period is tested by non-parametric statistical procedures. The seven constituents of water quality with the highly frequent detection in the area for this study are used for the statistical test. The shallow groundwater quality within the areas of the same land use at the time of investigation varies significantly according to the period of land usage. The concentration of KMnO$_4$consumed and hardness is significantly higher in the old residential area (of more than 20 years old) than in the younger one (of less than 10 years old). The quality of the shallow groundwater is also significantly different among the three categories with the similar period of land usage (of more than 15 years old). The concentration of No$_3$-N, hardness and total solid is significantly higher in the residential area than in the agricultural one (namely, the area used as paddy fields 2 to 5 years ago). The median concentration of these constituents is 2.2 to 3.8 times higher in the residential area than in the agricultural one. The concentration of NO$_3$-N, KMnO$_4$, consumed and Cl is significantly higher in the industrial area than in the agricultural one. The median concentration of these constituents is 5.5 to 18 times higher in the industrial area than in the agricultural one. The concentration of KMnO$_4$consumed is significantly higher in the industrial area than in the residential area. The median concentration of these constituents is 12 times higher in the industrial area than in the residential one. The spatial distribution of shallow groundwater quality in the rapidly urbanized area is closely related to the period of land usage as well as the land use, which is presumed to be attributed to the difference in the concentration and leakage rate of the contaminants leaking from damaged sewer into shallow groundwater.

• Journal of the Korean Arthroscopy Society
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• v.5 no.1
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• pp.22-26
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• 2001

Purpose : To confirm the efficacy of arthroscopic synovectomy fur the pigmented villonodular synovitis in the knee. Materials and Methods : Between October 1996 and February 2000, the arthroscopic synovectomy had been performed in six patients(six knee joints), whose diagnoses were confirmed by pathologist. All patients complained of painful swelling in involved knee and four of the six patients had trauma history. There were three male and three female patients. Average age was 35.8 years ranging from 16 to 67 years. Follow up period was average 22.7 months(range, $13\~53$ months). Results : According to arthroscopic findings, there were three localized forms and three diffuse forms. At their last follow-up examinations, all patients had improvement in pain, swelling and range of motion and there was no evidence of recurrence. Conclusion : Complete arthroscopic excision is the definitive treatment for localized pigmented villonodular synovitis and meticulous arthroscopic excision through all portals including posterior portal can be considered as a valid alternative to traditional open synovectomy for the patients with diffuse pigmented villonodular synovitis.

• Clinical and Experimental Pediatrics
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• v.49 no.6
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• pp.659-664
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• 2006

Purpose : To evaluate the morbidity and mortality of children with status epilepticus(SE) as an initial seizure and to compare these according to age groups. Methods : The 78 cases(38 cases <2 years and 38 cases ${\geq}2$ years) with SE as an initial seizure admitted to the Chonnam national university hospital from Jan. 2000 to Jan. 2004 were reviewed. Developmental profiles, laboratory findings, etiologies and seizure types of SE and outcomes were compared in between two age groups, under and over 2 years. Results : SE occurred predominantly in less than 5 years old. Febrile causes were the most common, which is significantly more in those under 2 years than over 2 years(P<0.05). whereas idiopathic and acute symptomatic causes were more common in those over 2 years(P<0.05). Generalized tonic-clonic seizures was the most common type. The mortality rate was 6.4 percent(5 cases : 1 case <2 years and 4 cases ${\geq}2$ years). The estimated occurrence of epilepsy after SE was 24.4 percent(19 cases : 8 cases <2 years and 11 cases ${\geq}2$ years). The neurologic sequelae after SE in cases that had developed normally before SE(62 cases : 32 cases <2 years and 30 cases ${\geq}2$ years) were observed in 20 cases(32.3 percent), and were more frequent over 2 years(21.9 percent vs. 43.3 percent, P<0.05). Conclusion : In this study death was less common and the neurologic sequelaes of SE as an initial seizure were less severe in children under 2 years of age. The reason seemed to be the difference in the etiology of SE with age.

• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.322-331
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• 2017

District heating was first introduced in Korea in 1985. As the service life of the underground thermal piping network has increased for more than 30 years, the maintenance of the underground thermal pipe has become an important issue. A variety of complex technologies are required for periodic inspection and operation management for the maintenance of the aged thermal piping network. Especially, it is required to develop a model that can be used for decision making in order to derive optimal maintenance and replacement point from the economic viewpoint in the field. In this study, the analysis was carried out based on the repair history and accident data at the operation of the thermal pipe network of five districts in the Korea District Heating Corporation. A failure probability model was developed by introducing statistical techniques of qualitative analysis and binomial logistic regression analysis. As a result of qualitative analysis of maintenance history and accident data, the most important cause of pipeline damage was construction erosion, corrosion of pipe and bad material accounted for about 82%. In the statistical model analysis, by setting the separation point of the classification to 0.25, the accuracy of the thermal pipe breakage and non-breakage classification improved to 73.5%. In order to establish the failure probability model, the fitness of the model was verified through the Hosmer and Lemeshow test, the independent test of the independent variables, and the Chi-Square test of the model. According to the results of analysis of the risk of thermal pipe network damage, the highest probability of failure was analyzed as the thermal pipeline constructed by the F construction company in the reducer pipe of less than 250mm, which is more than 10 years on the Seoul area motorway in winter. The results of this study can be used to prioritize maintenance, preventive inspection, and replacement of thermal piping systems. In addition, it will be possible to reduce the frequency of thermal pipeline damage and to use it more aggressively to manage thermal piping network by establishing and coping with accident prevention plan in advance such as inspection and maintenance.

• Tuberculosis and Respiratory Diseases
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• v.60 no.4
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• pp.419-425
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• 2006

Background : Severe community-acquired pneumonia (CAP) can develop into respiratory failure that requires mechanical ventilation (MV), which is associated with a higher rate of mortality. It was recently reported that a hydrocortisone infusion in severe CAP patients was associated with a significant reduction in the length of the hospital stay and mortality. This study evaluated efficacy of a hydrocortisone infusion for patients with severe CAP requiring MV. Methods : From February 2005 to July 2005, 13 patients (M : F = 10 : 3, mean age: $68.6{\pm}14.1years$), who were diagnosed with severe CAP and required MV, were enrolled in this study. Hydrocortisone was administered as an intravenous 200mg loading bolus, which was followed by an infusion at a rate of 10mg/hour for 7 days. The control group was comprised of patients with severe CAP requiring MV but in whom corticosteroid was not used before study period. The clinical and physiologic parameters on or by day 8 and the outcome in the hydrocortisone infusion group were compared with those in the control group. Results : 1) There was no significant difference in age, gender ratio, SAPS II, SOFA score, temperature, leukocyte count, PaO2/FiO2 (P/F) ratio, the number of patients with P/F ratio < 200, chest radiograph score, lung injury score and catecholamine-dependent septic shock between the hydrocortisone infusion group and control group at day 1. 2) At day 8, the proportion of patients with an improvement in the P/F ratio ${\geq}100$ and the chest radiograph score was significantly higher in the hydrocortisone infusion group than in the control group (61.5% vs. 15.4%, 76.9% vs. 23.1%, p< 0.05). However, there was no significant difference in the other clinical and physiologic parameters. 3). There was no significant difference in the duration of the MV, ICU stay, hospital stay and 10th and 30th day mortality between the two groups. Conclusion : Hydrocortisone infusion for patients with severe CAP requiring invasive mechanical ventilation may be effective in improving the level of oxygenation and the chest radiograph score.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.1
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• pp.34-41
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• 2016

Adult-onset type II citrullinemia (CTLN2) is characterized by episodes of neurologic symptoms associated with hyperammonemia leading to disorientation, irritability, seizures, and coma. CTLN2 is distinct from classical citrullinemia, which is caused by a mutation of the argininosuccinic acid synthetase (ASS) gene. The serum citrulline level is elevated, while the activity of ASS in liver tissue is decreased. CTLN2 is known to have a poor prognosis if the proper treatment is not taken. We reported a female aged 37 years who developed recurrent attacks of altered consciousness, aberrant behavior, and vomiting. We initially suspected the patient had CTLN2 because of the signs of hyperammonemic encephalopathy, such as altered mentality, memory disturbance, and aberrant behaviors provoked by exercise-induced stress and excessive intravenous amino acid administration. Through her peculiar diet preferences and laboratory findings that included hyperammonemia and citrullinemia, we diagnosed the patient as CTLN2, and SLC25A13 sequencing revealed known compound heterozygous mutations (IVS11+1G>A, c.674C> A). Her parents were heterozygous carriers, and we identified that her older sister had the same mutations. The older sister had not experienced any episodes of hyperammonemia, but she had peculiar diet preferences. The patient and her sister have been well with conservative management. When considering the clinical course of CTLN2, it was meaningful that the older sister could be diagnosed early in an asymptomatic period and that preemptive treatment was employed. Through this case, CTLN2 should be considered in adults who present symptoms of hyperammonemic encephalopathy without a definite etiology. Because of its rare incidence and similar clinical features, CTLN2 is frequently misdiagnosed as hepatic encephalopathy, and it shows a poor prognosis due to the lack of early diagnosis and proper treatment. A high-carbohydrate diet, which is usually used to treat other urea cycle defects, can also exaggerate the clinical course of CTLN2, so proper metabolic screening tests and genetic studies should be performed.

• Childhood Kidney Diseases
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• v.11 no.1
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• pp.51-58
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• 2007

Purpose : To assess the early complication of laparoscopic peritoneal dialysis catheter implantation in children. Methods : Medical record review was carried out on 21 laparoscopic and 16 conventional peritoneal dialysis catheter implantations which were performed in 31 children under 18 years of age between 2002 and 2006. All medical records were retrospectively analyzed. The patients were followed until 2 months after catheter placement. Patient characteristics and catheterrelated complications, such as significant bleeding, leakage, obstruction, migration, insertion site infection and peritonitis during the first 60 days after implantation were recorded. Results : After conventional operation, dialysate leakage occurred in 2 of 16 cases and all cases improved after conservative management. In 1 case, significant bleeding occurred and re-operation was performed. Three cases of obstruction due to migration were reported, 2 cases underwent reoperation and 1 case improved without intervention. After laparoscopic surgery, outflow obstruction occurred in 1 out of 21 cases, which was caused by adhesion after several reinsertions of the catheter and recurrent peritonitis. No migration was noted after laparoscopic surgery. There was no significant difference in the complication rate between the two groups. Conclusion : Laparoscopic peritoneal dialysis catheter placement is feasible in children of all age groups, with at least equivalent functional results compared to conventional surgery. The additional advantage of laparoscopic catheter insertion is the option to identify and eliminate anatomical risk factors, such as intra-abdominal adhesions, and to perform partial omentectomy without additional incisions.

• Pediatric Infection and Vaccine
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• v.11 no.1
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• pp.90-100
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• 2004

Objective : Urinary tract infection(UTI) is a frequent serious bacterial infection in young infants. The clinical presentation may be non-specific and variable, depends on factors such as the age and the level of infection. Children with renal involvement may be at risk of permanent renal damage. Experimental studies have shown that renal lesions caused by acute febrile UTI may be prevented or diminished by early diagnosis and treatment. Therefore, it is important to find a method that can permit early diagnosis and identification of patients who are at risk for progressive renal damage. We designed this study to identify related factors in culture positive UTI infants, and also to identify related factors in culture negative UTI infants, who are febrile with pyuria, by using renal imaging and functional studies including renal sonography, DMSA scan and VCUG. Methods : Retrospectively analyzed the medical records of 136 febrile infants with pyuria over 2 years(from January 2001 to February 2003). Urine culture was done in all cases, and regardless of urine culture findings, renal imaging study was done if symptomatic UTI suspected. Results : Total 57 organisms were isolated in 53 patients. E. coli was the most common organism(86%), followed by E. faecalis, M. morganii, Proteus species, P. aeruginosa, S. aureus and E. fergusonii. Most of the isolates had high sensitivity on cephalosporins or amikacin and had low sensitivities on aminopenicillins. Abnormal acute phase DMSA scan or VCUG findings were seen in both urine culture positive and negative group without statistical differences(P>0.05). In febrile infants with pyuria, fever over 48 hours, older age and high CRP related to abnormal acute phase DMSA scan findings regardless urine culture results. Conclusion : 1st or 3rd generation cephalosporins with amikacin could be the first choice of treatment for UTI. Febrile infants with positive urine culture dose mean urinary tract infection but not acute pyelonephritis which directly relates to cortical damage which could be confirmed by acute phase DMSA scan. Even cases with negative urine culture findings, acute pyelonephritis should be concerned in febrile infants with pyuria who are older than 3 months of age, has fever over 48 hours or high CRP level. And in such cases, acute phase DMSA scan and VCUG should be evaluated for early treatment and long term prognosis.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.12 no.2
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• pp.85-93
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• 2012

Purpose: Developmental delay is caused by very diverse etiologic diseases. Most chronic disorders has some influence on development. Chronic or acute disorders of CNS are main etiologic diseases of developmental delay. Up to now, over 60 diseases are included in organic acidopathies and most of them causes acute or chronic recurrent CNS damage and developmental delay. We have done this study to find out the importance of organic acidopathies causing developmental delay in Korean childhood and adolescent patients. Method: Retrograde analysis for 738 patients with developmental delay whose clinical informations are available and have done urine organic acid analysis for 5 years period, between Jan. 1st 2007 to Dec. 31th 2011. Statistical analysis was done with Student's t test using SPSS. Result: Out of 738 patients, 340 patients (46.1%) showed abnormalities on urine organic acid analysis. The most frequent disease was mitochondrial respiratory chain disorders (MRCD) (253, 34.3%), followed by ketolytic defects(39, 5.3%), 3-hydroxyisobutyric aciduria (26, 3.5%), glutaric aciduria type II (8, 1.1%), pyruvate dehydrogenase deficiency (3, 0.4%), 3-methylglutaric aciduria (2, 0.3%), glutaric aciduria type I (2, 0.3%), ethylmalonic aciduria (1, 0.15%), methylmalonic aciduria (1, 0.15%), HMG-CoA lyase deficiency (1, 0.15%), 3-methylcrotonylglycinuria (1, 0.15%), fatty acid oxidation disorders(1, 0.15%) and FAOD (1, 0.15%). Conclusion: Mitochondrial disorders are most frequent etiologic disease on all age group, followed by ketolytic defects and various organic acidopathies. The number and diversities of organic acidopathies emphasize meticulous evaluation of basic routine laboratory examinations and organic acid analysis with initial sample on every developmental patient.