• The Journal of the Acoustical Society of Korea
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• v.14 no.1E
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• pp.14-21
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• 1995

This paper presents a parallel sorting algorithm suitable for the SIMD multiprocessor. The algorithm finds pivots for partitioning the data into ordered subsets. The data can be evenly distributed to be sorted since it uses the probability theory. For n data elements to be sorted on p processors, when $n{\geq}p^2$, the algorithm is shown to be asymptotically optimal. In practice, sorting 8 million data items on 64 processors achieved a 48.43-fold speedup, while the PSRS required a 44.4-fold speedup. On a variety of shared and distributed memory machines, the algorithm achieved better than half-linear speedups.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5127-5131
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• 2013

Background: 5-fluoro-uracil (FU) is a common agent in postoperative chemoradiation in gastric adenocarcinoma. However, FU is not well tolerated in a significant proportion of patients. Capecitabine (CA) is an orally administered fluoropyrimidine carbamate which is preferentially converted to active 5-FU and is one of the agents used instead of FU in such cases. We compared the toxicity, local and distant control and survival rates with FU or oral CA during the course of concurrent radiotherapy to assess the role of CA used instead of FU. Materials and Methods: We conducted an analysis of survival, disease control and toxicity data in 46 patients treated with postoperative chemoradiation following total or subtotal gastrectomy for gastric adenocarcinoma with either FU or CA between January 2008 and December 2012. Results: Median follow-up was 19 months (range: 3-59), median survival time was 23 ({\pm}6.08) months and 1-3 years overall survival (OS) rates were 64.9-39% for all patients. Compared with the CA regimen, the incidence of treatment interruption was higher with FU (p=0.023), but no significant differences were seen in local control (p=0.510), distant recurrences (p=0.721) and survival rates (p=0.866) among patients. Conclusions: Concurrent CA with radiotherapy seems to be a more tolerable and an equally effective regimen for the postoperative treatment of gastric adenocarcinoma when compared to FU.

• Advances in pediatric surgery
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• v.9 no.1
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• pp.41-44
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• 2003

Appendicitis is the most common surgical emergency in childhood. Open appendectomy has been the standard treatment. The minimally invasive techniques have been adopted in children after experiences in various surgical conditions in adults has accumulated. It is debatable whether laparoscopic appendectomy (LA) is superior to open appendectomy (OA) in children. The goal of this study is to review the results of laparoscopy and laparotomy in the nonperforated appendicitis. The records of 22 patients under 15 years of age who were operated upon for nonperforated appendicitis at Asan Medical Center were analyzed between December 2002 and April 2003. Age, type and length of intervention, frequency of analgesic use, complication, length of hospitalization, and cost for each treatment groups (N=11) were compared. Laparoscopy patients were older (13.0 vs. 10.1 years; p > 0.05), and operative time was longer (55.0 vs. 35.0 minutes; p < 0.05). There was no conversion (OA to LA). The median length of hospital stay was significantly shorter in laparoscopy (3.0 vs. 2.0 days; p < 0.05). The median cost for LA was more expensive (W833, 836 vs. W751,398; p < 0.05). Even though there were higher costs and longer operative times with laparoscopic procedures, the shorter hospital stay was an advantage.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.161-161
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• 1998

• Advances in pediatric surgery
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• v.10 no.1
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• pp.31-34
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• 2004

The laparoscopic splenectomy (LS) became popular over the last 10 years. The advantage of LS over open splenectomy (OS) includes short hospital stay, improved cosmesis, less development of postoperative intestinal ileus, and less analgesics required. The purpose of this study is to evaluate the outcome of LS at Asan Medical Center from January 1999 to January 2003. The records of 14 consequent children who underwent splenectomy were reviewed retrospectively. Patients characteristics, morbidity, mortality, operative time, blood loss, and hospital stay were analyzed., Seven patients age 5 to 15 years underwent LS under the indications: idiopathic thrombocytic purpura (ITP, n=3), hereditary spherocytosis (n=3), and myelodysplastic syndrome (n=l). Seven patients, age 7 to 16 years, underwent OS during the same period for ITP (n=7). Median operative time was 120 mInutes (80 to 170 mins.) in OS, and 270 minutes (110 to 480 mins,) in LS (p<0.05). Median length of hospital stay was 6 days (3 to 8) in OS, and 4 days (3 to 6) in LS (p>0.05). Median splenic length was 12.0cm (9.2 to 18.0) in OS, 14.0 cm (10.0 to 19.5) (p>0.05). Accessory spleens were identified in 3 of 7 LS and 1 of 7 OS cases. In the LS group, there was no conversion to open surgery. Two patients in LS required blood transfusion postoperatively. LS in children can be performed as effectively and safely as OS.

• Journal of Korean Neurosurgical Society
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• v.58 no.4
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• pp.379-384
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• 2015

Objective : To investigate the risks and pattern of evolution of peritumoral brain edema (PTE) after stereotactic radiosurgery (SRS) for asymptomatic intracranial meningiomas. Methods : A retrospective study was conducted on 320 patients (median age 56 years, range 24-87 years) who underwent primary Gamma Knife radiosurgery for asymptomatic meningiomas between 1998 and 2012. The median tumor volume was 2.7 cc (range 0.2-10.5 cc) and the median follow-up was 48 months (range 24-168 months). Volumetric data sets for tumors and PTE on serial MRIs were analyzed. The edema index (EI) was defined as the ratio of the volume of PTE including tumor to the tumor volume, and the relative edema indices (rEIs) were calculated from serial EIs normalized against the baseline EI. Risk factors for PTE were analyzed using logistic regression. Results : Newly developed or increased PTE was noted in 49 patients (15.3%), among whom it was symptomatic in 28 patients (8.8%). Tumor volume larger than 4.2 cc (p<0.001), hemispheric tumor location (p=0.005), and pre-treatment PTE (p<0.001) were associated with an increased risk of PTE. rEI reached its maximum value at 11 months after SRS and decreased thereafter, and symptoms resolved within 24 months in most patients (85.7%). Conclusion : Caution should be exercised in decision-making on SRS for asymptomatic meningiomas of large volume (>4.2 cc), of hemispheric location, or with pre-treatment PTE. PTE usually develops within months, reaches its maximum degree until a year, and resolves within 2 years after SRS.

• Radiation Oncology Journal
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• v.37 no.2
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• pp.73-81
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• 2019

Purpose: There is sparse literature on treatment outcomes research on resectable oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to measure the treatment outcomes, explore the failure patterns, and identify the potential clinicopathological prognostic factors affecting treatment outcomes for resectable OTSCC. Materials and Methods: It is a retrospective analysis of 202 patients with resectable OTSCC who underwent upfront primary surgical resection followed by adjuvant radiotherapy with or without concurrent chemotherapy if indicated. Results: The median follow-up was 35.2 months (range, 1.2 to 99.9 months). The median duration of locoregional control (LRC) was 84.9 months (95% confidence interval, 67.3-102.4). The 3- and 5-year LRC rate was 68.5% and 58.3%, respectively. Multivariate analysis showed that increasing pT stage, increasing pN stage, and the presence of extracapsular extension (ECE) were significantly associated with poorer LRC. The median duration of overall survival (OS) was not reached at the time of analysis. The 3- and 5-year OS rate was 70.5% and 66.6%, respectively. Multivariate analysis showed that increasing pT stage and the presence of ECE were significantly associated with a poorer OS. Conclusion: Locoregional failure remains the main cause of treatment failure in resectable OTSCC. There is scope to further improve prognosis considering modest LRC and OS. Pathological T-stage, N-stage, and ECE are strong prognostic factors. Further research is required to confirm whether adjuvant therapy adds to treatment outcomes in cases with lymphovascular invasion, perineural invasion, and depth of invasion, and help clinicians tailoring adjuvant therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6151-6153
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• 2012

Background: An association between the ABO groups and pancreatic cancer has been shown previously, group A being significantly commoner in affected patients. We conducted the present study to investigate the prognostic effect of ABO blood group on overall survival of pancreas cancer patients. Methods: Patients who were diagnosed between 2005 and 2010 with pancreas cancer at Ankara Numune Education and Research Hospital were analyzed retrospectively. Patient demographics and ABO blood groups were obtained from medical charts. Results: Fifty pancreas cancer patients with known ABO blood group were included, 26 (52%) group A, 12 patients (24%) group 0, 9 (18%) group B, and 3 (6%) group AB. Blood group A pancreas cancer patient median age was 61.5 (39-80) years, with the median age of the other blood groups (B, AB,O) being 55.5 (32-74) years (p=0.14). 18% of patients with blood group A and 11% of the other blood group patients had metastasis (p=0.17) at the time of diagnosis. The median overall survival of blood group A pancreas patients was significantly lower than the other blood group patients, 7.6 (95%CI: 5.0-10.2) months versus 29.0 (95%CI: 0.0-68.8) months (p=0.05). Conclusions: Acccording to previously published cohort studies a relation may exist between ABO blood groups and cancer of pancreas. In this study we observed that pancreas cancer patients with blood group A have significantly worse overall survival than other blood groups.

• Archives of Plastic Surgery
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• v.44 no.5
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• pp.378-383
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• 2017

Background This study aimed to assess the effects of the topical application of tamoxifen on wound healing of burned skin in Wistar rats by evaluating 3 healing characteristics: fibrotic tissue thickness (FTT), scar surface area (SSA), and angiogenesis in the healed scar tissue. Methods Eighteen male Wistar rats were used in this study. A third-degree burn wound was made on the shaved animals' back, measuring $2{\times}2{\times}2cm$. In the first group, a 2% tamoxifen ointment was applied to the wound twice daily for 8 weeks. The second group received a placebo ointment during the same period. The third group did not receive any treatment and served as the control group. Results The median (interquartile range=[Q1, Q3]) FTT was 1.35 (1.15, 1.62) mm, 1.00 (0.95, 1.02) mm, and 1.25 (0.8, 1.5) mm in the control, tamoxifen, and placebo groups, respectively (P=0.069). However, the FTT in the tamoxifen group was less than in the placebo and control groups. The median angiogenesis was 3.5 (3.00, 6.25), 8.00 (6.75, 9.25), and 7.00 (5.50, 8.25) vessels per high-power field for the control, tamoxifen, and placebo groups, respectively (P=0.067). However, the median angiogenesis was higher in the tamoxifen group than in the control group. No significant difference was observed in the mean SSA between the tamoxifen group and the control group (P=0.990). Conclusions Local application of tamoxifen increased angiogenesis and decreased the FTT, with no change in the SSA in burned skin areas. These effects are expected to expedite the wound healing process, reducing contracture and preventing hypertrophic scar and keloid formation.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.15 no.1
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• pp.38-43
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• 2012

Purpose: Epstein-Barr virus (EBV) hepatitis is a usually asymptomatic and self-limiting disease in immunocompetent patients. However, the range of severity is wide, and the serological diagnosis is typically difficult until the convalescent phase. Thus, we examined the value of plasma EBV DNA real-time quantitative polymerase chain reaction (RT-qPCR) in EBV hepatitis for the timely diagnosis and the relationship between EBV viral load and clinical severity. Methods: Sixty samples were confirmed as having EBV infection by RT-qPCR with the EBV BALF5 gene sequence. We examined the clinical characteristics of EBV hepatitis by reviewing medical records. Results: The median total duration of fever was 8 days (range: 0-13 days). The mean peak value of aspartate aminotransferase (AST) was $241{\pm}214$ U/L, and the mean peak value of alanine aminotransferase (ALT) was $298{\pm}312$ U/L. There was no correlation between the serum levels of liver enzyme and plasma EBV DNA titer ($p$=0.1) or between median total duration of fever and EBV DNA titer ($p$=0.056). The median age of the EBV VCA IgM-negative group was lower compared with the EBV VCA IgM-positive group in EBV hepatitis (2 years vs. 6 years, $p$=0.0009). Conclusion: The severity of EBV hepatitis does not correlate with circulating EBV DNA load according to our data. Furthermore, we suggest that plasma EBV PCR may be valuable in young infants in whom the results of serology test for EBV infection commonly are negative.