• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.533-539
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• 2010

Stem cell-based therapy is under intensive investigation to treat acute renal failure (ARF). The purpose of this study was to evaluate available ARF models, and suggest a model appropriate to therapeutic evaluation of the stem cells in preclinical approach by determining the optimum concentration of nephrotoxic agents and duration of ischemia induction. Three different types of available acute kidney injury (AKI) animal models were analyzed using rats: Cisplatin (saline, 5 and 7.5 mg/kg, IP) or glycerol (saline, 8 and 10 ml/kg, IM)-induced nephrotoxicity as toxic models and ischemia-induced (sham, 35 and 45 minutes) nephropathy as an ischemic model. The relevance and applicability to investigate especially the regenerative ability of stem cells were evaluated regarding morphology, renal function and survival at this time point. In the point of renal function, 10 ml glycerol/kg and 7.5 mg cisplatin/kg model in toxic models and 45 min model in ischemia models showed significant decrease for the longer observation time compared to 8 ml glycerol/kg, 5 mg cisplatin/kg and the 35 min ischemia models, respectively. All groups were observed no mortality except 45 min-ischemia model with 50% survival. Histological significant alterations including cast formation in the tubular lumen, tubular necrosis and apoptosis were revealed on the second day in either ischemiaor glycerol-induced models, and on day 5 in cisplatin-induced models. The results indicate that ischemia 35 min-, cisplatin 7.5 mg/kg- and glycerol 10 ml/kg-induced AKI would be ideal animal models to monitor a outcome parameter related to the therapeutic effects on renal function with noninvasive techniques in the same animal at multiple time points. Our findings also suggest that the best time points for the functional or histological interpretation of renal will be on day 2 in both glycerol- and ischemia-induced AKI models and on day 5 in cisplatin-induced AKI.

• Korea journal of population studies
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• v.16 no.2
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• pp.65-83
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• 1993

The purpose of this study is estimate limits of Korean life expectancy at birth by 'Gompertz growth curse Model', 'Cause-Elimination Model' and Multidimensional models of Senescencee and Mortality'. Data used in Gompertz curve were obtained from all life tables published from 1905 to 1990 in Korea, and life expectancies at birth of eighteen groups were selected at five-year interval in consideration of time-series changes. Data used in Cause-Elimination Model are 'Cause of Death statistics in 1991' published in 1992 by National Bureau of Statistics of Korea and 'life table of 1989' published in 1990 by National Bureau of Statistics, Economic Planning Board of Korea. The materials are all classifiable death data, 119, 253 cases of male and 82, 420 cases of female, which is from 1991 Causes of Death statistics. The cases of death analyzed belong to one of 8 categories; i.e., Infectious and Parasitic Diseases(001-139; with notation of Infectious Diseases), Malignant Neoplasms(140-208), Hypertensive Diseases(401-405), Ischemic Heart Dieases and Diseases of Pulmonary Circulation and Other Forms of Heart Diseases(410-429;with notation of Heart Disease), Cerebrovascular Diseases(430-438), Chronic Liver Diseases and Cirrhosis(571; with notation of Liver Diseases), Injury and Poisoning(800-999) and all other disease. Data used in 'Multidimensional models of senescence and mortality' were life table of 1989 published by National Bureau of statistics, Economic Planning Board of Korea and life table of 1970, 1978-79, 1983, 1985 and 1987. The major findings may be summarised as follows: 1. Estimate equations of Gompertz growth curve using life expectancy at birth during the 1905-1990 period are as the following. Male : y = 88.047697 $\times$ $0.199690^{0.903381x}$ Female : y = 95.632828 $\times$ $0.199690^{0.903381x}$ Limits of life expectancy at birth, which were estimated by Gompertz growth curve, are 88.05 for male and 95.63 for female. 2. The effect on life expectancy at birth eliminationg all causes death is 14.04 years(for male) and 10.86 years(for female). Astonishingly, eliminating the malignant neoplasms increase life expectancy at birth by 2.85 years for male 2.03 years for female in 1991. In table 8 we show the effect on life expectancy at birth of separately eliminating each of the 8 categorical causes of death. The theoretical limit to life expectancy by Cause-Elimination Model is 80.96 for male and 85.82 for female. 3. If the same rate of delay [0.376 year(male), 0.435 year(femable) per calendar year] continued, then life expectancy at birth would reach 74.82(male) years and 84, 10(female) years in 2010. With 14.04-years(male) and 10.86-years(female) effect attributable in 2010 would be 88.86 years(male) and 94.96(femable) years. 4. 'Multidimensional models of senescence and death' permits calculations of the value of the attribution coefficient (B), percent of loss per year of physiologic function. The results of Ro and B during the 1970-1989 period are listed in table 9. Estimate of limit to Korean life expectancy at birth by 'Multidimensional models of senescence and death' is 99.47 years for male and 104.74 years for female in 1989.

• Journal of Chest Surgery
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• v.48 no.1
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• pp.40-45
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• 2015

Background: Surgical enucleation is the treatment of choice for esophageal submucosal tumors (SMTs) with symptomatic, larger, or ill-defined lesions. The enucleation of SMTs has traditionally been performed via thoracotomy. However, minimally invasive approaches have recently been introduced and successfully applied. In this study, we present our experiences with the thoracotomic and thoracoscopic approaches to treating SMTs. Methods: We retrospectively reviewed 53 patients with SMTs who underwent surgical enucleation between August 1996 and July 2013. Demographic and clinical features, tumor-related factors, the surgical approach, and outcomes were analyzed. Results: There were 36 males (67.9%) and 17 females (32.1%); the mean age was $49.2{\pm}11.8$ years (range, 16 to 79 years). Histology revealed leiomyoma in 51 patients, a gastrointestinal stromal tumor in one patient, and schwannoma in one patient. Eighteen patients (34.0%) were symptomatic. Fourteen patients underwent a planned thoracotomic enucleation. Of the 39 patients for whom a thoracoscopic approach was planned, six patients required conversion to thoracotomy because of overly small tumors or poor visualization in five patients and accidental mucosal injury in one patient. No mortality or major postoperative complications occurred. Compared to thoracotomy, the thoracoscopic approach had a slightly shorter operation time, but this difference was not statistically significant ($120.0{\pm}45.6$ minutes vs. $161.5{\pm}71.1$ minutes, p=0.08). A significant difference was found in the length of the hospital stay ($9.0{\pm}3.2$ days vs. $16.5{\pm}5.4$ days, p<0.001). Conclusion: The thoracoscopic enucleation of submucosal esophageal tumors is safe and is associated with a shorter length of hospital stay compared to thoracotomic approaches.

• Journal of Korean Neurosurgical Society
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• v.30 no.7
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• pp.849-854
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• 2001

Delayed cerebral infarction after resection of craniopharyngioma is a uncommon entity, but leads to high morbidity and mortality. We present 3 such cases and discuss the etiology and pathogenesis with review of pertinent literatures. In our cases, delayed deterioration of consciousness was observed in all cases. All of them expired. The cause may be multifactorial and the surgical approach may contribute to the pathogenesis of delayed cerebral infarction. We suspect vasospasm might be the major mechanism of pathogenesis. Vessels were primed to spasm during operation due to blood in the cistern or mechanical injury. Vasoactive materials may have been liberated from the pituitary stalk or injured hypothalamus, either at the time of surgery, or later, after portions of tumor have undergone necrosis. The high degree of suspicion to detect vasospasm should be done in the case of the delayed deterioration of mental status at an early stage of craniopharyngioma surgery. Possible mechanism underlying this delayed cerebral infarction are discussed.

• Journal of Chest Surgery
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• v.51 no.5
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• pp.344-349
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• 2018

Background: We report our surgical technique for nonintubated uniportal video-assisted thoracoscopic surgery (VATS) pulmonary resection and early postoperative outcomes at a single center. Methods: Between January and July 2017, 40 consecutive patients underwent nonintubated uniportal VATS pulmonary resection. Multilevel intercostal nerve block was performed using local anesthesia in all patients, and an intrathoracic vagal blockade was performed in 35 patients (87.5%). Results: Twenty-nine procedures (72.5%) were performed in patients with lung cancer (21 lobectomies, 6 segmentectomies, and 2 wedge resections), and 11 (27.5%) in patients with pulmonary metastases, benign lung disease, or pleural disease. The mean anesthesia time was 166.8 minutes, and the mean operative duration was 125.9 minutes. The mean postoperative chest tube duration was 3.2 days, and the mean hospital stay was 5.8 days. There were 3 conversions (7.5%) to intubation due to intraoperative hypoxemia and 1 conversion (2.5%) to multiportal VATS due to injury of the segmental artery. There were 7 complications (17.5%), including 3 cases of prolonged air leak, 2 cases of chylothorax, 1 case of pleural effusion, and 1 case of pneumonia. There was no in-hospital mortality. Conclusion: Nonintubated uniportal VATS appears to be a feasible and valid surgical option, depending on the surgeon's experience, for appropriately selected patients.

• Journal of Trauma and Injury
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• v.30 no.3
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• pp.80-86
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• 2017

Purpose: To analyze the data of patients who suffered trauma in a cultivator accident and visited the trauma center in rural Gyeongbuk Province. Methods: We retrospectively reviewed the medical records and Korean Trauma Data Bank data of 120 patients who suffered cultivator-related traumas and visited the rural regional trauma center in Gyeongbuk Province from January to December 2015. Results: The age of the patients ranged from 35 to 96 years (mean, 70 years). Ninety-one (75.8%) patients were men, and twenty-nine (24.2%) were women. Most of the patients were in their 70s (46 men [50.5%] and 13 women [44.8%]). In total, 113 patients (94.1%) arrived at the regional trauma center by ground transport and 7 (5.9%) arrived by air transport. Ninety-eight patients (81.7%) were transported to the regional trauma center directly from the scene of the accident, and twenty-two (18.3%) were transferred from another medical institute. The mean time from the accident to arrival at the emergency department was 139 minutes, and only 46 patients (38.3%) arrived within 1 hour. Twelve (10.0%) patients died, including two deaths on arrival and two post- cardiopulmonary resuscitation deaths in the emergency department. All deaths were of male cultivator operators. The causes of death were shock (hypovolemic, traumatic, or septic), subdural hematoma (open), hemothorax, rhabdomyolysis, and pneumonia. Conclusions: As the government - led regional trauma center project is on process, it would be clinically important to summarize the initial outcome of cultivator injuries, which are characteristically found more in regional trauma centers in the rural area, and have high mortality. Based on this study, in the future, it will be necessary to follow up and analyze more number of patients and to construct accurate database about trauma cases related to cultivator in Gyeongbuk region.

• Journal of Korean Critical Care Nursing
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• v.9 no.1
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• pp.40-50
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• 2016

Purpose: Continuous renal replacement therapy (CRRT) has become the preferred dialysis method to support critically ill children and neonates with acute kidney injury. Using CRRT on neonates has increased, but reports about experience are limited. The aim of this study is to describe the clinical application, outcomes, and complications of CRRT in children and neonates. Methods: A retrospective review was performed in 135 children and 36 neonates who underwent CRRT at a tertiary hospital from 2008 to 2015. Results: At the initiation of CRRT, the median age of children was 72 months and the corrected age of neonates was 37.1 weeks. Median body weight of neonates was 3.2 kg. In neonates, initial degree of fluid overload [FO%], blood flow rate [BFR] and ultrafiltration rate [UFR] rate during CRRT were higher than in children. Median real time of CRRT was 90.5 and 53.5 hours in children and neonates, respectively. Downtime of CRRT was 0.7 and 1.3 hours/day. Median mortality rates (44.4% vs.47.2%) and complication rates were similar between the groups. Conclusion: CRRT can be used for a wide range of critically ill children and neonates. Different application methods of CRRT can contribute to increased survival of neonates.

• Journal of Korean Neurosurgical Society
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• v.65 no.1
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• pp.130-137
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• 2022

Objective : COVID-19 has spread worldwide since the first case was reported in Wuhan, China, in December 2019. Our institution is a regional trauma and emergency center in the northern Gyeonggi Province. The changing trend of patient care in the emergency room of this hospital likely reflects the overall trend of patients in the area. In the present study, whether changes in the surrounding social environment following the outbreak of COVID-19 changed the incidence of neurosurgical emergency patients and whether differences in practice existed were investigated. Methods : The overall trend was analyzed from January 2020 which is before the outbreak of COVID-19 to September 2020. To remove bias due to seasonal variation, the previous 2 year's records during the same period were reviewed and compared. Confirmed COVID-19 patients in the northern Gyeonggi Province were identified using data released by the government. And patients who came to the emergency department with head trauma and stroke were identified. Results : Based on the present study results, the total number of neurosurgery emergency patients decreased over the study period. In the trauma patient group, the number of patients not involved in traffic accidents significantly decreased compared with patients involved in traffic accidents. Among the stroke cases, the rate of ischemic stroke was lower than hemorrhagic stroke, although a statistically significant difference was not observed. Meanwhile, an increase in the risk of mortality associated with trauma or stroke cases was not observed during the COVID-19 outbreak compared with the same time period in the previous year. Conclusion : Due to the occurrence of COVID-19, non-essential activities have decreased and trauma cases not associated with traffic accidents appeared to decrease. Due to the decrease in overall activity, the number of stroke patients has also decreased. This trend is expected to continue even in the post-COVID-19 era, and accordingly, the results from the present study are relevant especially if the current situation continues.

• Journal of Korea Water Resources Association
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• v.38 no.5 s.154
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• pp.365-377
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• 2005

This paper presents numerical works carried out for developing an advanced computational framework for understanding injury- and mortality-inducing flow phenomena in hydropower facilities. Large-eddy simulation (LES) of a circular jet flow is carried out to help interpret the results of recent experiments that exposed live fish to the shear zone of a turbulent jet. The instantaneous flow field of LES is characterized by intense velocity, pressure, and vorticity fluctuations, which could exert forces and moments on a fish considerably larger than those exerted by the same fish exposed to the corresponding steady, time-averaged flow. In this study, also, unsteady modeling of flow in a hydroturbine draft tubewas carried out using a hybrid unsteady RANS/LES, so-called detached-eddy simulation (DES). Results from DES show that the potential for disorientation and excessive residence times of fish within the draft tube is certainly considerable.

• Journal of Korean Neurosurgical Society
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• v.29 no.11
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• pp.1469-1475
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• 2000

Objective : The goal of this study was to evaluate the clinical outcome of the posterior C1-2 transarticular screw fixation without C1-2 sublaminar wiring in atlantoaxial instability. Methods : Between Apr. 1995 and Feb. 2000, we used this technique in treat randomly selected 17 patients (11 men, 6 women) who had atlantoaxial instability. The causes of instability were : type II-A odontoid process fracture(10 cases) ; type II-P odontoid process fracture(1 case) ; Os odontoideum(2 cases) ; transverse ligament laxity due to rheumatoid disease(1 case) ; and, transverse ligament injury without bone fracture(3 cases). All cases were operated with posterior C1-2 transarticular screw fixation with 3.5mm cortical screw and interlaminar iliac graft without sublaminar wire fixation. The mean follow-up period was 28 months(5 to 58 months) and the mean age at the time of operation was 41 years(15 to 68 years). All Patients were allowed to ambulate with Philadelphia neck collar on the first post-operation day. Results : Bony fusion was successfully achieved in all cases demonstrated at 3-month follow-up studies. There was no operative mortality or morbidity. Conclusion : The authors conclude that the posterior transarticular screw fixation without C1-2 sublaminar wiring provide adequate stability with high bony union rate in atlantoaxial instability of various causes.