• Macromolecular Research
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• v.9 no.6
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• pp.313-318
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• 2001

The present study relates to a method of manufacturing 100$\mu\textrm{m}$ thick cover layer for the high density digital versatile disc system (HD-DVD), which uses a high numerical aperture of 0.85 at 405 nm wavelength. Spin coating technique was investigated as means for manufacturing the cover layer within sufficient margins of thickness variation and with good mechanical properties including small radial and tangential tilts. The influence of processing variables such as spinning speed, spinning time, and dispensing position was investigated. The effect of viscosity of UV-curable resin was also investigated.

• Quality Improvement in Health Care
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• v.14 no.1
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• pp.49-54
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• 2008

Background : This study was to reduce incidence of falls by analyzing actual problem and drawing out improvement plan applicable to the clinical practice through operation of the staff nurses-centered fall peer review group. Method : The fall peer review group was composed of 8 nurses having patient nursing experience for over 5 years, and each of fall cases was reviewed and the root cause was analyzed. As a result, it was found that the patients and their families did not fully understandthe content of the education, and the staff nurses did not completely inspect the risk factors of falls and perform immediate intervention when patient's condition changed. Based on the above-mentioned results, improvement activity was conducted for the purposes of consolidating patients education method and supplementing computerized system to support nurses' decision making as well as devices and facilities. Result : As a result of conducting improvement activity in the aspects of education for patients, support of nurse's decision-making, and devices and facilities through operation of the staff nurses-centered fall peer review group, falls decreased by 9.5% compared to before improvement activity. Conclusion : It is concluded that operation of the clinical nurses-centered fall peer review group played a role of promoter to draw out practical and applicable improvement plan to the clinical practice and apply directions of the field-centered, and increased nurses' interest in falls and ultimately, reduced incidence of falls. Therefore the Center will continue to operate the staff nurses-centered peer review group, and recommends participation of nurses who actually take the charge of nursing patients in further analysis of patients' safety accidents.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.3
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• pp.175-179
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• 2015

Purpose: Infants with Alagille syndrome (AGS) are occasionally misdiagnosed as biliary atresia and subsequently undergo Kasai operation. The purpose of this study was to investigate the outcome of patients with AGS who had previously received Kasai operation during infancy. Methods: This retrospective study was conducted at the Department of Pediatrics, Samsung Medical Center. We compared the prognosis and mortality between those who had undergone Kasai operation during infancy (Kasai group) and those who had not (non-Kasai group). Results: Among the 15 children with AGS, five had received Kasai operation, while 10 had not. All subjects in the Kasai group revealed neonatal cholestasis, while 70% of the non-Kasai group showed neonatal cholestasis. Liver transplantation was performed in 100% (5/5) among the Kasai group, and 20.0% (2/10) among the non-Kasai group (p=0.007). Mortality was observed in 60.0% (3/5) among the Kasai group, and 10.0% (1/10) among the non-Kasai group (p=0.077). Conclusion: Although overall mortality rate did not significantly differ between the two groups, the proportion of patients receiving liver transplantation was significantly higher in the non-Kasai group. The relatively worse outcome in AGS patients who had received Kasai operation may be due to the unfavorable influences of Kasai operation on the clinical course of AGS, or maybe due to neonatal cholestasis, irrespective of the Kasai operation.

• Journal of the Korean Ceramic Society
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• v.46 no.2
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• pp.131-136
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• 2009

Radio frequency (RF) plasma treatment is studied for the size reduction and the spheroidization of coarse particles to change them into nano-sized powders of spherical shape in MLCC fields. The uni-nanoadditives manufactured by RF plasma processing for high dispersion have been investigated for the effect on core-shell structure in dielectrics of MLCC. Microstructures have been characterized using scanning electron microscope (SEM), transmission electron microscope (TEM) and Electron Probe Micro Analyzer (EPMA). We compared the distribution of core-shell grains between specimens manufactured using uni-nanoadditive and using mixed additive. In addition, the uniformity of rare earth elements in the core-shell structured grains was analyzed. It was shown, from TEM observations, that the sintered specimen manufactured using uni-nanoadditives had more dense small grains with well-developed core-shell structure than the specimen using mixed additives, which had a homogeneous microstructure without abnormal grain growth and shows broad temperature coefficient of capacitance (TCC) curves in all temperature ranges because of well dispersed additives.

• Journal of Korean Neurosurgical Society
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• v.64 no.2
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• pp.271-281
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• 2021

Objective : Immune checkpoint inhibitors (ICIs) are approved for treating non-small-cell lung cancer (NSCLC); however, the safety and efficacy of combined ICI and Gamma Knife radiosurgery (GKS) treatment remain undefined. In this study, we retrospectively analyzed patients treated with ICIs with or without GKS at our institute to manage patients with brain metastases from NSCLC. Methods : We retrospectively reviewed medical records of patients with brain metastases from NSCLC treated with ICIs between January 2015 and December 2017. Of 134 patients, 77 were assessable for brain responses and categorized into three groups as follows : group A, ICI alone (n=26); group B, ICI with concurrent GKS within 14 days (n=24); and group C, ICI with non-concurrent GKS (n=27). Results : The median follow-up duration after brain metastasis diagnosis was 19.1 months (range, 1-77). At the last follow-up, 53 patients (68.8%) died, 20 were alive, and four were lost to follow-up. The estimated median overall survival (OS) of all patients from the date of brain metastasis diagnosis was 20.0 months (95% confidence interval, 12.5-27.7) (10.0, 22.5, and 42.1 months in groups A, B, and C, respectively). The OS was shorter in group A than in group C (p=0.001). The intracranial disease progression-free survival (p=0.569), local progression-free survival (p=0.457), and complication rates did not significantly differ among the groups. Twelve patients showed leptomeningeal seeding (LMS) during follow-up. The 1-year LMS-free rate in treated with ICI alone group (69.1%) was significantly lower than that in treated with GKS before ICI treatment or within 14 days group (93.2%) (p=0.004). Conclusion : GKS with ICI showed no favorable OS outcome in treating brain metastasis from NSCLC. However, GKS with ICI did not increase the risk of complications. Furthermore, compared with ICI alone, GKS with ICI may be associated with a reduced incidence of LMS. Further understanding of the mechanism, which remains unknown, may help improve the quality of life of patients with brain metastasis.

• Korean Journal of Radiology
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• v.1 no.1
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• pp.38-42
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• 2000

Objective: The purpose of this study was to determine the utility of preoperative CT in predicting early recurrence of hepatocellular carcinoma after partial hepatic resection. Materials and Methods: Preoperative three-phase helical CT scans in 53 patients with hepatocellular carcinoma were retrospectively reviewed by two radiologists. In 27 patients (group I), HCC had recurred within six months, while 26 (group II) had remained disease free for at least two years. In each group, preoperative CT findings were evaluated in each group for the tumor size and number, the presence or absence of capsule, distinctness of tumor margin, perinodular extension, and the presence or absence of portal vein thrombosis. Results: In group I, a tumor capsule of tumor was seen in five of 27 patients (19%), and in group II, in 16 of 26 (62%) (p = .001). The tumor margin was distinct in eight patients (30%) in group I and in 20 (77%) in group II (p = .001). Multiple tumors, perinodular extension, and portal vein thrombosis were more frequently seen in group I but the differences were not statistically significant (p > .05). Tumor size was similar in each group (p > .05). Conclusion: Preoperative CT findings that may help predict the early recurrence of hepatocellular carcinoma after surgical resection are an absence of capsule of tumors and an indistinct margin. Reference to these findings during preoperative CT can guide clinicians in their choice of treatment.

• Journal of Chest Surgery
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• v.56 no.3
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• pp.197-203
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• 2023

Background: The survival benefit of coronary artery bypass grafting (CABG) using the bilateral internal thoracic arteries (BITA) is well known; however, the role of BITA in concomitant aortic valve replacement (AVR) and CABG has not been studied. Methods: We retrospectively reviewed patients who underwent concomitant AVR and CABG. Cases not using an internal thoracic artery and less than 2 bypass grafts were excluded. We enrolled 114 patients in this study. The mean follow-up duration was 61.5±43.5 months. Results: Forty patients (35.1%) underwent CABG with a single internal thoracic artery (SITA) and 74 patients (64.9%) underwent CABG with BITA. The preoperative clinical characteristics were not significantly different between the 2 groups, with the exception of a higher prevalence of atrial fibrillation in the SITA group. Postoperative mortality and morbidity were not significantly higher in the BITA group than in the SITA group. In the univariable analysis, the survival of the BITA group was similar to that of the SITA group (p=0.157). Multivariable analysis showed that only mean age was a predictor of death (p=0.042), but using BITA was not an independent predictor (p=0.094). In low-risk patients whose preoperative ejection fraction was >45%, the survival of the BITA group was significantly better than that of the SITA group (p=0.043). Conclusion: BITA use in concomitant AVR and CABG showed no difference in mortality compared to using SITA. Although its impact on long-term survival was inconclusive, BITA use can be considered for low-risk patients.

• Journal of Korean Neurosurgical Society
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• v.29 no.2
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• pp.217-221
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• 2000

Objective : Brainstem hemorrhages usually result in much higher mortality and morbidty than any other intracranial vascular lesions. The purpose of the study is to evaluate the relationship of the radiological classification of the lesions and the clinical outcomes, and to evaluate the value of such classification on the choice of management modality. Method : Thirty seven patients with primary brainstem hemorrhage were managed medically or surgically between Oct. 1995 and Mar. 1998. The lesions were classified as two groups based on radiological findings as follows : Focal subependymal hematoma(group I, n＝7) and diffuse tegmentobasilar hemorrhage(group II, n＝30). The outcomes at discharge were retrospectively reviewed according to such classification. Result : The most common clinical pictures and radiological findings in each group were as followings : 1) Group I : focal compressive lesion which displaces rather than destroys brain tissue. It occurs in a younger age group and causes neurological deficits which are often partially reversible. Operative hematoma evacuation was performed in 43.3%. Their mean improved Glasgow Coma Scale(GCS) score was 4.7. 2) Group II : hypertensive brain stem hemorrhage. It usually causes a diffuse lesion occurring in an older age group and most often associated with profound irreversible neurological deficits which are often fatal. Operative hematoma evacuation was performed in 16.7%. Their mean improved GCS score was 1.4. In both conservatively treated group I and II has no siginificant clinical improvement. Conclusion : Although there is an overlap among them and the size of the group is small, the pathophysiologic classification of this lesion based on clinical features and radiological findings may be useful for decision of treatment method.

• Journal of muscle and joint health
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• v.12 no.2
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• pp.143-154
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• 2005

Purpose: The aim of this study was to investigate the effects of home care exercise program on knee joint function(WOMAC) and the quality of life in patient with total knee replacement arthroplasty. Method: Forty-one subjects were sampled according to research criteria, and divided into two groups : 21 out of experimental group and 20 out of control group. The patients having treatment of total knee replacement arthroplasty were out of the hospital. After surgery executed, it took 8days for them to recovere their health conditions since 10th day, the experimental group received the home care exercise program per regularly four days interval. Results: 1) After applying home care exercise program, the total score on the WOMAC Index for the control group was $3.09{\pm}.76$. The score of the experimental group was $3.55{\pm}.55$ which is statistically higher than that of the control group. (P=.007). 2) After applying home care exercise program, the score of the quality of life for the control group was $3.09{\pm}.50$. The score of the experimental group was $3.46{\pm}.35$ Which is statistically higher than that of the control group. (P=.007). Conclusion: This figures show that home care exercise program has good results. These findings also indicate that the services of home care exercise program are alternatives for the hospitalization.

• Journal of Korean Neurosurgical Society
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• v.66 no.1
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• pp.24-32
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• 2023

Objective : With the recent increase in mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the role of neurosurgeons in AIS treatment has become increasingly important. This study aimed to assess the outcomes of patients with AIS treated by neurosurgeons and neurologists in the emergency room (ER) of a tertiary hospital in South Korea. Methods : From January 2020 to June 2021, 536 patients with AIS within 24 hours of symptom onset were admitted to our hospital via the ER. Based on the type of doctors who provided initial care for AIS in the ER, patients were divided into two groups : (a) neurosurgeon group (n=119, 22.2%) and (b) neurologist group (n=417, 77.8%). Results : Intravenous tissue plasminogen activator (tPA) was administered in 82 (15.3%) of 536 patients (n=17 [14.3%] in the neurosurgeon group and n=65 [15.6%] in the neurologist group). The door-to-tPA time was not significantly different between both groups (median, 53 minutes; interquartile range [IQR], 45-58 vs. median, 54 minutes; IQR, 46-74; p=0.372). MT was performed in 69 patients (12.9%) (n=25, 36.2% in the neurosurgeon group and n=44, 63.8% in the neurologist group). The neurosurgeon group achieved a shorter door-to-puncture time than the neurologist group (median, 115 minutes; IQR, 107-151 vs. median, 162 minutes; IQR, 117-189; p=0.049). Good clinical outcomes (3-month modified Rankin Scale 0-2) did not differ significantly between the two groups (96/119 [80.7%] vs. 322/417 [77.2%], p=0.454). Conclusion : The neurosurgeon group showed similar door-to-treatment time and clinical outcomes to the neurologist group in patients with AIS in the ER. This study suggests that neurosurgeons have comparable abilities to care for patients with AIS in the ER.