• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3461-3464
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• 2012

Methotrexate (MTX) is an important drug for the treatment of childhood acute lymphoblastic leukemia (ALL). However, related toxicity occurs in many organs which may cause interruption of treatment, morbidity, and mortality. Single nucleotide polymorphisms (SNPs) of dihydrofolate reductase (DHFR) and gamma glutamyl hydrolase (GGH) are known to alter their enzymatic activity and thus affect the metabolism of MTX and influence the effectiveness. Therefore, we hypothesized that genetic variations of DHFR and GGH genes may influence the risk of toxicity after high dose MTX. The study population comprised of 105 children with ALL who were treated according to the modified St Jude Total XV protocol. The patients received 2.5 or $5g/m^2$ of MTX for 5 doses during the consolidation phase. Genotyping of DHFR 829C>T and GGH-401C>T was performed using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The GGH-401CT and TT genotypes were associated with increased risk of leukopenia and thrombocytopenia after high dose MTX (OR 2.97, 95%CI; 1.24-7.13 and OR 4.02, 95%CI; 1.58-10.26). DHFR 829C>T was not associated with toxicity. In conclusion, the GGH-401CT and TT genotypes were found to increase the risk of severe leukopenia and thrombocytopenia after exposure to high dose MTX for childhood ALL therapy.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.1
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• pp.53-60
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• 2009

Maxillary deficiency, anterior cross bite, constriction of maxillary arch, malaligned teeth are frequently observed in patients with cleft lip and palate. Surgery and orthodontics, combined intervention are needed to correct maxillary deficiency. Distraction osteogenesis that currently used has many advantages like less relapse tendency, more advancement of maxilla, capable in growing patients. In case 1, 18 years old girl with BCLP had severe midfacial deficiency and multiple missing of teeth. LeFort I osteotomy, followed by maxillary distraction osteogenesis utilizing rigid external distraction device(RED) system, was performed. After a 6-day latency period, distraction proceeded at a rate of 1mm per day (at 1st week, 1.5mm/day). Total advancement was 19mm. The RED device left in place for the additional 4 weeks for consolidation. After the RED device was removed, face mask was applied with elastic traction for 5 weeks. After achieving acceptable facial appearance and occlusion, orthodontic appliance was removed. The results after 4 years follow-up was sustained pretty well without aggravation of velopharyngeal function. In case 2, 22 years old man with UCLP had severe midfacial deficiency and palatally erupted upper 2nd premolars due to arch length discrepancy, but the anterior segment of maxillary did not show constriction and crowding. patient had no arch width discrepancy, crowding was concentrated on premolar region. Segmental LeFort I osteotomy was performed. After a 6 - day latency period, using internal distraction device, distraction proceeded at a 0.5mm per day(at 1st week, 0.75 - 1 mm/day). Total advancement was 15mm. After internal distraction device was removed, face mask was applied with elastic traction for 4 weeks. After surgical-orthodontic treatment, facial appearance and occlusion was improved pretty good, and after 46 months follow-up the result was retained well.

• Journal of the Korean Society for Heat Treatment
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• v.31 no.4
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• pp.171-179
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• 2018

Copper powder dispersed with 4 vol.% of $Cr_2O_3$ was successfully produced by a simple milling at 210 K with a mixture of $Cu_2O$, Cu and Cr elemental powders, followed by Hot Pressing (HP) at 1123 K and 50 MPa for 2h to consolidate the milled powder. The microstructure of the HPed material was characterized by standard metallographic techniques such as XRD (X-ray Diffraction), TEM and STEM-EDS. The results of STEMEDS analysis showed that the HPed materials comprised a mixture of nanocrystalline Cu matrix and $Cr_2O_3$ dispersoid with a homogeneous bimodal size distribution. The mechanical properties of the HPed materials were characterized by micro Vickers hardness test at room temperature. The thermodynamic considerations on the heat of formation, the incubation time to ignite MSR (Mechanically induced Self-sustaining Reaction), and the adiabatic temperature for the heat of displacement reaction between the oxide-metal are made for the delayed formation of $Cr_2O_3$ dispersoid in terms of MSR suppression. The results of TEM observation and hardness test indicated that the relatively large dispersoids in the HPed materials are attributed to the significant coarsening for the high temperature consolidation; this leads to the low Vickers hardness value. Based on the thermodynamic calculation for the operating processes with a limited number of parameters, the formation kinetics and coarsening of the $Cr_2O_3$ dispersoid are discussed.

• Korean Journal of Metals and Materials
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• v.46 no.3
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• pp.182-188
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• 2008

Carbon nanotubes(CNTs) have outstanding mechanical, thermal, and electrical properties. Thus, by placing nanotubes into appropriate matrix, it is postulated that the resulting composites will have enhanced properties. Cold spray can produce thick metal-based composite coatings with very high density, low oxygen content, and phase purity, which leads to excellent physical properties. In this study, we applied cold spray coating process for the consolidation of Cu/CNT composite powder. The precursor powder mixture, in which CNTs were filled into copper particles, was prepared to improve the distribution of the CNT in copper matrix. Pure copper coating was also conducted by cold spraying as a reference. Annealing heat treatment was applied to the coating to examine its effect on the properties of the composite coating. The hardness of Cu/CNT composite coating represented similar value to that of pure copper coating. It was importantly found that the electrical conductivity of the Cu/CNT composite coating significantly increased from 53% for the standard condition to almost 55% in the optimized condition, taking annealed ($500^{\circ}C/1hr$.) copper coating as a reference (100%). The thermal conductivity of Cu/CNT composite coating layer was higher than that of pure Cu coating. It was also found that the electrical and thermal conductivities of Cu/CNT composite could be improved through annealing heat treatment. The microstructural evolution of Cu/CNT coating was also investigated and related to the macroscopic properties.

• Proceedings of the Korean Geotechical Society Conference
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• 1991.10a
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• pp.332-347
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• 1991

Accurate prediction of future settlement is essential for the settlement control of soft soil by pre-loading method. To predict future settlement in clayey soft soils, several methods like Asaoka method, Hyperbolic Method and Hoshino method are currently being used. These methods predict the future sett1ement by mathmatical treatment of the measured settlement data on the basis of consolidtion theory and empiricism. But the correlation coefficient between the measured and the predicted settlement was relatively low (0.8~0.9). Also, the prediction of future settlemet for the design load is very difficult. In this article, the measured field settlement data was treated as the the field consolidation test. Hence, condolidation coefficient(Cv) and compression index(Cc) was evaluated from the field settlement data. Cv and Cc values from field data was used to calculate the degree of consolidation and settlement at desired time. By this method, the correlation coefficent between the measured and the predicted settlement was significantly increased(0.97~0.99). Also the settlement by the design load after the improvement of soft soil could be predicted reasonably. This method is quite rational and sound but it requires thousands of calculation steps. Today, by the aid of low priced personal computers above mentioned technique could be used much acre economically and effectively than conventional methods. This article presented the mechanisms and capacities of this method and demonstrated the enhanced correlation coefficient when applied to actual field settlement data.

• Tuberculosis and Respiratory Diseases
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• v.78 no.3
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• pp.196-202
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• 2015

Background: Viridans streptococci (VS) are a large group of streptococcal bacteria that are causative agents of community-acquired respiratory tract infection. However, data regarding their clinical characteristics are limited. The purpose of the present study was to investigate the clinical and radiologic features of community-acquired pneumonia (CAP) with or without parapneumonic effusion caused by VS. Methods: Of 455 consecutive CAP patients with or without parapneumonic effusion, VS were isolated from the blood or pleural fluid in 27 (VS group, 5.9%) patients. Streptococcus pneumoniae was identified as a single etiologic agent in 70 (control group) patients. We compared various clinical parameters between the VS group and the control group. Results: In univariate analysis, the VS group was characterized by more frequent complicated parapneumonic effusion or empyema and bed-ridden status, lower incidences of productive cough, elevated procalcitonin (>0.5 ng/mL), lower age-adjusted Charlson comorbidity index score, and more frequent ground glass opacity (GGO) or consolidation on computed tomography (CT) scans. Multivariate analysis demonstrated that complicated parapneumonic effusion or empyema, productive cough, bed-ridden status, and GGO or consolidation on CT scans were independent predictors of community-acquired respiratory tract infection caused by VS. Conclusion: CAP caused by VS commonly presents as complicated parapneumonic effusion or empyema. It is characterized by less frequent productive cough, more frequent bed-ridden status, and less common CT pulmonary parenchymal lesions. However, its treatment outcome and clinical course are similar to those of pneumococcal pneumonia.

• Tuberculosis and Respiratory Diseases
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• v.67 no.1
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• pp.37-41
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• 2009

Lymphocytic interstitial pneumonia (LIP) is a rare disorder characterized by a diffuse infiltration of the alveolar space, interstitium by lymphocytes, plasma cells, and reticuloendothelial cells. Although its etiology is unknown, LIP has been associated with autoimmune disorders and with viral infections. Because it's clinical and radiographic features are nonspecific, a confirmatory diagnosis is performed by open lung biopsy. A 59-year-old female presented dry cough, which had been present for 1 month. On initial findings of multifocal consolidation at the right middle lobe on both lower lobes in chest radiography, the first diagnosis of cryptogenic organizing pneumonia was suggested. On open lung biopsy, LIP was diagnosed. The patient had no autoimmune disease, viral infection or monoclonal gammopathy. After 3 months of corticosteroid treatment, the patient experienced improved symptoms, reduced abnormalities on chest radiography, and improved pulmonary function testing.

• Tuberculosis and Respiratory Diseases
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• v.65 no.2
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• pp.147-151
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• 2008

Non-resolving or slowly resolving pulmonary infiltrates in spite of administering adequate antimicrobial therapy are a clinical diagnostic challenge for physicians. The rate of radiographic resolution varies with the patients' age, the underlying comorbidities, the extent of radiographic involvement, the functional status and the causal pathogens. It is important to differentiate non-resolving or slowly resolving bacterial pneumonia from other uncommon infectious pneumonias or malignancies that require invasive diagnostic techniques to confirm the diagnosis. Bronchioloalveolar carcinoma can present with various clinical and radiographic features. Unfortunately, the radiographic similarity of consolidative BAC to pneumonia often leads to an incorrect diagnosis of pneumonia and possibly significant delays in obtaining appropriate diagnostic studies. We describe here a case of a mixed adenocarcinoma and bronchioloalveolar carcinoma that was initially diagnosed as pneumonia due to the consolidation pattern on the radiography and the patient's initial improvement with antibiotic treatment.

• Radiation Oncology Journal
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• v.24 no.4
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• pp.230-236
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• 2006

$\underline{Purpose}$: To analyze the response, toxicity, patterns of failure and survival rate of patients with locally advanced non-small cell lung cancer who were treated with concurrent chemoradiotherapy with weekly paclitaxel. $\underline{Materials\;and\;Methods}$: Twenty-three patients with locally advanced non-small cell lung cancer patients who received radical chemoradiotherapy from October 1999 to September 2004 were included in this retrospective study. Patients received total $55.4{\sim}64.8$ (median 64.8) Gy (daily 1.8 Gy per fraction, 5 days per weeks) over $7{\sim}8$ weeks. 50 or $60\;mg/m^2$ of paclitaxel was administered on day 1, 8, 15, 22, 29 and 36 of radiotherapy. Four weeks after the concurrent chemoradiotherapy, three cycles of consolidation chemotherapy consisted of paclitaxel $135\;mg/m^2$ and cisplatin $75\;mg/m^2$ was administered every 3 weeks. $\underline{Results}$: Of the 23 patients, 3 patients refused to receive the treatment during the concurrent chemoradiotherapy. One patient died of bacterial pneumonia during the concurrent chemoradiotherapy. Grade 2 radiation esophagitis was observed in 4 patients (17%). Sixteen patients received consolidation chemotherapy. During the consolidation chemotherapy, 8 patients (50%) experienced grade 3 or 4 neutropenia and one of those patients died of neutropenic sepsis. Overall response rate for 20 evaluable patients was 90% including 4 complete responses (20%) and 14 partial responses (70%). Among 18 responders, 9 had local failure, 3 had local and distant failure and 2 had distant failure only. Median progression-free survival time was 9.5 months and 2-year progression-free survival rate was 19%. Eleven patients received second-line or third-line chemotherapy after the treatment failure. The median overall survival time was 21 months. 2-year and 5-year survival rate were 43% and 33%, respectively. Age, performance status, tumor size were significant prognostic factors for progression-free survival. $\underline{Conclusion}$: Concurrent chemoradiotherapy with weekly paclitaxel revealed high response rate and low toxicity rate. But local failure occurred frequently after the remission and large tumor size was a poor prognostic factor. Further investigations are needed to improve the local control.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.1
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• pp.51-64
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• 2022

For effective preservation of the rocks, which bearing plant fossils at Gumkwangdong Formation, Pohang, the properties of rock and treatment of chemicals were examined in an artificial weathering test. The rocks are diatomaceous siliceous mudstone, which contain a small amount of smectite and has developed laminated layers. The rocks react with water, the d₀₀₁ spacing of smectite was increased. On the one hand, the physical properties of the rock samples, such as surface hardness, improved after the application of ethyl silicate-based stone strengthener. On the other hand, the spacing of interlayer of swelling clay minerals decreased and spacing of laminae layer increased. When the ethyl silicate-based stone strengthener was applied after pretreatment with a swelling inhibitor, interlayer and spacing of laminae changes were similar to those when only the stone strengthener was treated. The effect of the swelling inhibitor was almost negligible. When the rocks that have been conserved with chemicals react with water, spacing of laminae has widened much, whereas when the rocks was in contact with moisture only, there was little change. In addition, if it is placed in the outdoor after conservation treatment, although it occurs slightly slower than the untreated rock, the separation of the lamination layer and the pulverization of the rock occur within a very short time. Consolidation is required to improve the physical properties of fossil rock, but when exposed to rain and undergoing freeze-thaw process, the effect is lost very quickly. Therefore, regardless of the chemical treatment, it is a priority to prevent direct rainfall contact with the rock.