• Progress in Medical Physics
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• v.35 no.1
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• pp.16-19
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• 2024

A new E_n score of the proficiency test (PT) is formulated; it is applicable when a correlation exists between the reference and participant's values. Based on the uncertainty propagation rule given in ISO/IEC Guide 98-3 (GUM:1995), the E_n score covering the correlation case is newly developed for the PT. The new E_n score will be applied in a future PT organized by the Korea Research Institute of Standards and Science (KRISS) dosimetry team. The new E_n score will enhance measurement traceability and contribute to improving the quality management system of participants in the KRISS PT by avoiding performance underestimation.

• Journal of Gastric Cancer
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• v.19 no.2
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• pp.212-224
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• 2019

Purpose: Splenic hilar lymph node dissection (LND) during total gastrectomy is regarded as the standard treatment for proximal advanced gastric cancer (AGC). This study aimed to investigate whether splenic hilar LND or D2 LND is essential for proximal AGC of pT2- 4aN0M0 stage. Materials and Methods: Data of curative total gastrectomies (n=370) performed from 2000 to 2010 for proximal AGC of pT2-4aN0 stage were retrospectively reviewed. Clinicopathological characteristics and long-term outcomes were compared using propensity score matching between patients who underwent splenectomy (n=43) and those who did not (n=327) and between patients who underwent D2 LND (n=122) and those who underwent D1+ LND (n=248). Results: Tumors of larger size and a more advanced T stage and significantly lower overall and relapse-free survival (P<0.001) were observed in the splenectomy group than in the 2 spleen-preserving groups. Before propensity score matching, worse overall and relapse-free survival (P<0.001) was observed in the splenectomy group than in the non-splenectomy group. After matching, although the overall survival became similar (P=0.123), relapse-free survival was worse in the splenectomy group (P=0.021). Compared with D1+ LND, D2 LND had no positive impact on the overall (P=0.619) and relapse-free survival (P=0.112) after propensity score matching. Conclusions: Splenic hilar LND with or without splenectomy may not have an oncological benefit for patients with pathological AGC with no LN metastasis.

• Journal of KIISE
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• v.42 no.10
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• pp.1286-1293
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• 2015

Most e-marketplaces build a reputation system that provides potential buyers with reputation scores of sellers in order for buyers to identify the sellers that are more reliable and trustworthy. The reputation scores are computed based on the aggregation of buyers' ratings. However, when these ratings are used to compute the reputation scores, the existing reputation systems do not make a distinction according to the following two criteria: the capability of the seller and the quality of an item. We claim that a reputation system needs to separate the two criteria in order to provide more precise information about the seller. In this paper, we propose a method to compute seller's reputation by separating the rating into the seller's score and the item's score. The proposed method computes the reputation of the seller's capability by using only the 'seller's score' and helps potential buyers to find reliable sellers who provide fast delivery and better service. In experiments, we propose a simulation strategy that reflects the real life of an E-marketplace and verify the effectiveness of our method by using the generated simulation data.

• Journal of The Korean Society of Clinical Toxicology
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• v.6 no.1
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• pp.32-36
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• 2008

Purpose: The major complication of acute organophosphate (OP) poisoning is respiratory failure as a result of cholinergic toxicity. Many clinicians find it difficult to predict the optimal time to initiate mechanical ventilation (MV) weaning, and as a result have tended to provide a prolonged ventilator support period. The purpose of this study is to determine any clinical predictors based on patients characteristics and laboratory findings to assist in the optimal timing of mechanical ventilator weaning. Methods: We reviewed medical and intensive care records of 44 patients with acute OP poisoning who required mechanical ventilation admitted to medical intensive care unit between July 1998 and June 2007. Patient information regarding the poisoning, clinical data and demographic features, APACHE II score, laboratory data, and serial cholinesterase (chE) levels were collected. Base on the time period of MV, the patients were divided into two groups: early group (wean time < 7 days, n = 28) and delayed group (${\geq}$ 7 days, n = 16). Patients were assessed for any clinical characteristics and predictors associated with the MV weaning period. Results: During the study period, 44 patients were enrolled in this study. We obtained the sensitivity and specificity values of predictors in the late weaning group. APACHE II score and a reciprocal convert of hypoxic index but specificity (83.8%) is only APACHE II score. Also, the chE concentration (rho = -0.517, p = 0.026) and APACHE II score (rho = 0.827, p < 0.001) correlated with a longer mechanical ventilation duration. Conclusion: In patients with acute OP poisoning who required mechanical ventilation, the APACHE II scoring system on a point scale of less than 17 and decrements in cholinesterase levels on 1-3 days were good predictors of delayed MV weaning.

• Korean Medical Education Review
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• v.20 no.3
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• pp.141-149
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• 2018

This study examined doctors' images represented in the Korean press to identify overall public perceptions of doctors and to suggest areas for improvement to enhance their image. All news reports published in the two major Korean daily newspapers between years 2011 and 2015 related to doctors and the practice of medicine were searched and collected. The news reports were categorized into the five competency domains in the Korean doctor's role (i.e., patient care, communication and cooperation, social accountability, professionalism, and education and research). Each news item was coded as being either positive or negative and was given a score regarding the extent to which positive or negative image that it represents of doctors using the Doctor Image Scale (DIS) score. A total of 314 news reports were collected, a majority of which were on patient care (36%), professionalism (33%), and social accountability (23%). Positive stories slightly outnumbered negative ones (56% vs. 44%). The largest number of positive news reports was in patient care (n=82); negative news reports most frequently appeared in professionalism (n=99) and patient care (n=32). The total DIS score was also positive (+28): the highest positive DIS score was in social accountability (+164); the highest negative DIS score was obtained in professionalism (-226). This study revealed overall positive portrayals of doctors in the Korean press, yet doctors need to better comply with regulations and ethical guidelines and enhance their medical knowledge and clinical skills and to improve their image.

• Hip & pelvis
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• v.30 no.4
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• pp.210-218
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• 2018

Purpose: This is a report on the outcomes associated with a consecutive series of 1,000 cementless hip arthroplasties utilizing the $Bencox^{(R)}$ hip stem-the first Korean-developed hip prosthesis. Materials and Methods: A consecutive series of 1,000 hip arthroplasties using the $Bencox^{(R)}$ hip stem were analyzed, starting from its initial release (September 2006) until June 2014. Patients in this consecutive series underwent surgery for fractures (n=552), arthritis (n=155), avascular necrosis (n=209), and revisions (n=84). Of these 1,000 cases, patients with a minimum follow-up of at least 1 year (n=616) were retrospectively analyzed for radiographic and clinical outcomes (i.e., Harris hip score). The stability of the prosthesis was evaluated by examining subsidence. Results: During the follow-up period (mean follow-up period of 54.8 months), there were 2 cases requiring revision of the femoral stem-both were caused by periprosthetic fractures and neither involved stem loosening. The mean Harris hip score during follow-up was 95.5. Bone ongrowth occurred in 95% of patients; no cases of subsidence or aseptic loosening of the stem were detected, and no cases of postoperative complications such as ceramic breakage were observed. Conclusion: Clinical and radiographic evaluations of hip arthroplasty using the $Bencox^{(R)}$ hip stem revealed excellent outcomes with an average of 54.8 month follow-up in a consecutive series of 1,000 cases.

• Clinical and Experimental Pediatrics
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• v.53 no.8
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• pp.790-794
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• 2010

Purpose: The purpose of this study was to test the efficacy of treating the pain among newborn infants associated with a medical procedure with sucrose with regard to overall physiological and behavioral stability. Methods: 103 newborn infants were enrolled in this study. The control group (n=63) did not receive any treatment. The experimental group (n=40) received 2 mL of 24% sucrose solution two minutes before a routine heel stick. The pain was assessed by measurements of physiological changes [e.g. pulse rate, oxygen saturation, salivary cortisol (hydrocortisone)] and behavioral changes [e.g. crying time, and the neonatal infant pain scale (NIPS) for neonates]. Results: There were no differences among the groups with respect to physiological changes associated with the pain from the procedure. However, there were significant group differences in behavioral changes to the pain. In the control group, the median crying time was 13 seconds, while in the experimental group, the median crying time was 3.5 seconds ($P$=.000). In the control group the median NIPS score was 4, while in the experimental group the median NIPS score was 2 ($P$=.000). Conclusions: These findings suggest that sucrose can be an effective method for the management of stress responses in infants with regard to behavior. However, this treatment had no significant physiological effects.

• Korean Journal of Radiology
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• v.22 no.9
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• pp.1514-1524
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• 2021

Objective: To develop a radiomics risk score based on dynamic contrast-enhanced (DCE) MRI for prognosis prediction in patients with glioblastoma. Materials and Methods: One hundred and fifty patients (92 male [61.3%]; mean age ± standard deviation, 60.5 ± 13.5 years) with glioblastoma who underwent preoperative MRI were enrolled in the study. Six hundred and forty-two radiomic features were extracted from volume transfer constant (K^trans), fractional volume of vascular plasma space (V_p), and fractional volume of extravascular extracellular space (V_e) maps of DCE MRI, wherein the regions of interest were based on both T1-weighted contrast-enhancing areas and non-enhancing T2 hyperintense areas. Using feature selection algorithms, salient radiomic features were selected from the 642 features. Next, a radiomics risk score was developed using a weighted combination of the selected features in the discovery set (n = 105); the risk score was validated in the validation set (n = 45) by investigating the difference in prognosis between the "radiomics risk score" groups. Finally, multivariable Cox regression analysis for progression-free survival was performed using the radiomics risk score and clinical variables as covariates. Results: 16 radiomic features obtained from non-enhancing T2 hyperintense areas were selected among the 642 features identified. The radiomics risk score was used to stratify high- and low-risk groups in both the discovery and validation sets (both p < 0.001 by the log-rank test). The radiomics risk score and presence of isocitrate dehydrogenase (IDH) mutation showed independent associations with progression-free survival in opposite directions (hazard ratio, 3.56; p = 0.004 and hazard ratio, 0.34; p = 0.022, respectively). Conclusion: We developed and validated the "radiomics risk score" from the features of DCE MRI based on non-enhancing T2 hyperintense areas for risk stratification of patients with glioblastoma. It was associated with progression-free survival independently of IDH mutation status.

• Childhood Kidney Diseases
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• v.2 no.2
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• pp.125-132
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• 1998

Purpose : To study whether a low protein diet increase the efficacy of antihypertensive therapy on the progression of renal failure, we conducted an experimental study using 5/6 nephrectomized rats(n=63). Methods : At 7 days after surgery, rats were randomly assigned to three groups according to receiving antihypertensive drug: no antihypertensive drug (U), enalapril (E), and nicardipine (N), respectively and fed a low protein diet (6$\%$ protein). Proteinuria, mesangial matrix expansion score and glomerular volume were assessed at 4, 12 and 16 weeks after renal ablation. Results : Group U rats on a low protein diet developed progressive hypertension ($140{\pm}8,\;162{\pm}5,\;171{\pm}5\;and\;184{\pm}11\;mmHg$ at 4, 8, 12 and 16 weeks) which were controlled by E and N. Group U rats on a low protein diet developed proteinuria ($74{\pm}15\;mg/day$ at 16 weeks) which were decreased by E ($42{\pm}12 mg/day$) or N ($48{\pm}8 mg/day$) (p<0.05). Mesangial matrix expansion score and glomerular volume were not different between groups U, E and N on a low protein diet regardless of the antihypertensive drugs administered. Conclusion : A low protein diet did not affect blood pressure. Enalapril and nicardipine-treated rats on a low protein diet did not have different mesangial matrix expansion and glomerular volumes from rats on a low protein diet at 12 weeks and 16 weeks, in spite of the better controlling of systemic hypertension and lessening of proteinuria. Thus, combined treatment with a low protein diet and antihypertensive drugs didn't appear to show any addition,11 effects to attenuate glomerular injury.

• The Korean Journal of Nuclear Medicine
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• v.25 no.1
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• pp.95-100
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• 1991

Computerized scintigraphv using $^{99m}Tc-DTPA$ was performed to 37 isolated rabbit kidneys after preservation for 48 hours in perfusates differing in their compositions, i. e., Group 1 (N 9) in Collins' solution, Group 2 (N 10) in Collins' plus trifluoperazine, Group 3 (N 9) in Collins' plus urokinase and Group 4 (N 9) in Collins pius urokinase plus verapamil. Satisfactory images, and statistically analyzable quantitative indices such as perfusion score, filtration rate and cortical uptake ratio (CUR) were obtained by the evaluations of first-pass perfusion, equilibration slopes and postequilibration images. Significant improvements in CUR were observed by adding trifluoperazine (Group 2) and urokinase (group 3) as compared to Collins' only group (Group 1), p<0.05 for each, and all of the three indices (perfusion score, filtration rate and CUR) were also significantly (p=0.0092 p<0.05 and p<0.05) improved by adding urokinase plus verapamil (Group 4). We concluded that the computerized scintigraphy with Tc-99m DTPA provide valuable quantitative indices for evaluation of preserved kidney funcitions and suggest its possible clinical applicability in cadaver kidney transplantation considering the safety and easiness of the prodedure.