• Journal of Community Nutrition
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• 제5권2호
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• pp.83-92
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• 2003

Several self-administered dietary assessment questionnaires have recently been developed, validated, and used in nutritional epidemiological and clinical studies in Japan. This article describes recent evidence on development and validation of them. After extensive search of published articles both in English and Japanese languages, we identified 25 articles on 13 questionnaires of which validation studies have existed. Number of foods/menus assessed varied from 31 to 169 according to questionnaires. Eleven questionnaires were food frequency type, either with fixed portion size or semiquantitative, and two diet history types. All the 13 questionnaires were validated against intakes assessed with dietary record or 24-hour recall, and only two with biomarkers. Number of subjects used in the studies was between 23 and 350. All the studies used adult subjects. In the studies with dietary record or recall, the correlation coefficient for or orgy intake was between 0.22 and 0.65 (median = 0.44). Median correlation coefficient for nutrients was between 0.21 and 0.61. In the studies with biomarkers, serum marine-origin n-3 polyunsaturated fatty acids and carotenes, and urinary potassium seemed useful biomarkers. In conclusion, recent progress of this field in Japan is remarkable. But more research is needed for validation studies with biomarkers, and the development and validation of questionnaires for children and elderly subjects. (J Community Nutrition 5(2) : 83∼92,2003)

• Journal of Mechanical Science and Technology
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• 제20권11호
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• pp.1873-1880
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• 2006

The results of this study suggest the use of a Back Propagation Network (BPN) algorithm for the detection of esophageal erosions or abnormalities - which are the important signs of esophagitis - in the analysis of the color and textural aspects of clinical images obtained by endoscopy. The authors have investigated the optimization of the learning condition by the number of neurons in the hidden layer within the structure of the neural network. By optimizing learning parameters, we learned and have validated esophageal erosion images and/or ulcers functioning as the critical diagnostic criteria for esophagitis and associated abnormalities. Validation was established by using twenty clinical images. The success rates for detection of esophagitis during calibration and during validation were 97.91% and 96.83%, respectively.

• Korean Journal of Radiology
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• 제25권2호
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• pp.189-198
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• 2024

Objective: To investigate the prognostic utility of radiomics features extracted from ¹⁸F-fluorodeoxyglucose (FDG) PET/CT combined with clinical factors and metabolic parameters in predicting progression-free survival (PFS) and overall survival (OS) in individuals diagnosed with extranodal nasal-type NK/T cell lymphoma (ENKTCL). Materials and Methods: A total of 126 adults with ENKTCL who underwent ¹⁸F-FDG PET/CT examination before treatment were retrospectively included and randomly divided into training (n = 88) and validation cohorts (n = 38) at a ratio of 7:3. Least absolute shrinkage and selection operation Cox regression analysis was used to select the best radiomics features and calculate each patient's radiomics scores (RadPFS and RadOS). Kaplan-Meier curve and Log-rank test were used to compare survival between patient groups risk-stratified by the radiomics scores. Various models to predict PFS and OS were constructed, including clinical, metabolic, clinical + metabolic, and clinical + metabolic + radiomics models. The discriminative ability of each model was evaluated using Harrell's C index. The performance of each model in predicting PFS and OS for 1-, 3-, and 5-years was evaluated using the time-dependent receiver operating characteristic (ROC) curve. Results: Kaplan-Meier curve analysis demonstrated that the radiomics scores effectively identified high- and low-risk patients (all P < 0.05). Multivariable Cox analysis showed that the Ann Arbor stage, maximum standardized uptake value (SUVmax), and RadPFS were independent risk factors associated with PFS. Further, β2-microglobulin, Eastern Cooperative Oncology Group performance status score, SUVmax, and RadOS were independent risk factors for OS. The clinical + metabolic + radiomics model exhibited the greatest discriminative ability for both PFS (Harrell's C-index: 0.805 in the validation cohort) and OS (Harrell's C-index: 0.833 in the validation cohort). The time-dependent ROC analysis indicated that the clinical + metabolic + radiomics model had the best predictive performance. Conclusion: The PET/CT-based clinical + metabolic + radiomics model can enhance prognostication among patients with ENKTCL and may be a non-invasive and efficient risk stratification tool for clinical practice.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2425-2430
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• 2013

A simple, fast and robust analytical method was developed to determine imatinib in human plasma using liquid chromatography-tandem mass spectrometry with electrospray ionization in the positive ion mode. Imatinib and labeled internal standard were extracted from plasma with a simple protein precipitation. The chromatographic separation was performed using an isocratic elution of mobile phase involving 5.0 mM ammonium formate in water-5.0 mM ammonium formate in methanol (30:70, v/v) over 3.0 min on reversed-stationary phase. The detection was performed using a triple-quadrupole tandem mass spectrometer in multiple-reaction monitoring mode. The developed method was validated with lower limit of quantification of 10 ng/mL. The calibration curve was linear over 10-2000 ng/mL ($R^2$ > 0.99). The method validation parameters met the acceptance criteria. The spiked samples and standard solutions were stable under conditions for storage and handling. The reliable method was successfully applied to real sample analyses and thus a pharmacokinetic study in 27 healthy Korean male volunteers.

• Korean Journal of Radiology
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• 제22권6호
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• pp.912-921
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• 2021

Objective: To compare the performance of the deep learning-based lesion detection algorithm (DLLD) in detecting liver metastasis with that of radiologists. Materials and Methods: This clinical retrospective study used 4386-slice computed tomography (CT) images and labels from a training cohort (502 patients with colorectal cancer [CRC] from November 2005 to December 2010) to train the DLLD for detecting liver metastasis, and used CT images of a validation cohort (40 patients with 99 liver metastatic lesions and 45 patients without liver metastasis from January 2011 to December 2011) for comparing the performance of the DLLD with that of readers (three abdominal radiologists and three radiology residents). For per-lesion binary classification, the sensitivity and false positives per patient were measured. Results: A total of 85 patients with CRC were included in the validation cohort. In the comparison based on per-lesion binary classification, the sensitivity of DLLD (81.82%, [81/99]) was comparable to that of abdominal radiologists (80.81%, p = 0.80) and radiology residents (79.46%, p = 0.57). However, the false positives per patient with DLLD (1.330) was higher than that of abdominal radiologists (0.357, p < 0.001) and radiology residents (0.667, p < 0.001). Conclusion: DLLD showed a sensitivity comparable to that of radiologists when detecting liver metastasis in patients initially diagnosed with CRC. However, the false positives of DLLD were higher than those of radiologists. Therefore, DLLD could serve as an assistant tool for detecting liver metastasis instead of a standalone diagnostic tool.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6819-6822
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• 2014

Background: The aim of this study was to evaluate the accuracy of a new scoring system in Korean patients with hematuria at high risk of bladder cancer. Materials and Methods: A total of 319 consecutive patients presenting with painless hematuria without a history of bladder cancer were analyzed, from the period of August 2012 to February 2014. All patients underwent clinical examination, and 22 patients with incomplete data were excluded from the final validation data set. The scoring system included four clinical parameters: age (${\geq}50$ = 2 vs. <50 =1), gender (male = 2 vs. female = 1), history of smoking (smoker/ex-smoker = 4 vs. non-smoker = 2) and nature of the hematuria (gross = 6 vs. microscopic = 2). Results: The area under the receiver-operating characteristic curve (95% confidence interval) of the scoring system was 0.718 (0.655-0.777). The calibration plot demonstrated a slight underestimation of bladder cancer probability, but the model had reasonable calibration. Decision curve analysis revealed that the use of model was associated with net benefit gains over the treat-all strategy. The scoring system performed well across a wide range of threshold probabilities (15%-45%). Conclusions: The scoring system developed is a highly accurate predictive tool for patients with hematuria. Although further improvements are needed, utilization of this system may assist primary care physicians and other healthcare practitioners in determining a patient's risk of bladder cancer.

• 한국간호교육학회지
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• 제22권2호
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• pp.137-151
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• 2016

Purpose: The purpose of this study was to develop and validate a Nurse's Character Scale for Care in Clinical settings (NCS_C). Methods: The NCS_C was developed and validated as follows: Item generation, preliminary test of questionnaire, and tests of validity and reliability. One hundred and thirty six preliminary items were developed through a literature review and in-depth interviews by 10 nurse-experts and five patients. The content validity of the items was verified through an evaluation by five nurses and seven professors in the fields of Korean literature, pedagogy and nursing. Finally, 53 items were confirmed through item analysis, factor analysis and validity tests including convergent, discriminant and concurrent validities. Data were analyzed using factor analysis, Pearson correlation coefficients, and Cronbach's alpha. Results: Thirteen factors evolved from the factor analysis, which explained 63.1% of the total variance. The factors referred to the union of two dimensions: the professional dimension and the interpersonal dimension. The internal consistency, Cronbach's alpha, was .95, and reliability of the subscales ranged from .58 to .87. Conclusion: The results of this study suggest that the NCS_C is a reliable and valid primary scale to measure nurses' or students' character level for better care in clinical settings.

• 한국의학물리학회지:의학물리
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• 제27권4호
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• pp.267-271
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• 2016

In this study, we present the commissioning and validation results of a dedicated scanning nozzle. The dedicated scanning nozzle is installed in one of the two gantry treatment rooms at Samsung Proton Therapy Center. Following a successful completion of the acceptance test, the commissioning process including the beam data measurement for treatment planning system has been conducted. Extended measurements have been conducted as a validation of the clinical performance of the nozzle and various quality assurance protocols have been prepared.

• 한국임상약학회지
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• 제22권1호
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• pp.55-64
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• 2012

The quinolones are broad-spectrum antibiotics and enhanced antimicrobial activity has extended the use of the quinolones beyond the traditional indications for quinolone antibiotics in the treatment of urinary tract infections. The quinolones are effective in a wider variety of infectious diseases, including skin and respiratory infections. Because of their excellent safety and tolerability, they have become popular alternatives to penicillin and cephalosporin derivatives in the treatment of various infections. A retrospective study was performed to evaluate efficacy and safety of IV quinolones for inpatient use. Total 117 patients who administerd quinolones for longer than 3 continuous days at community hospital from October 1st, 2008 to December 31st, 2008 were reviewed. The criterias for drug evaluation were included the validation of indication, outcome, dosage and side effects. In the results, ciprofloxacin 13 (total 93), levofloxacin 3 (total 59) and moxifloxacin 2 (total 19) cases were not met the criterias based on the culture results. Major indications were pneumonia (ciprofloxacin 16.3%, levofloxacin 67.8%, moxifloxacin 84.2%), urinary tract infection (ciprofloxacin 44.1%), skin infection (ciprofloxacin 7.5%, levofloxacin 20.3%, moxifloxacin 10.5%), intra-abdominal infection (ciprofloxacin 10.8%, moxifloxacin 5.3%), etc.. In the results of quinolone monotherapy, the frequencies were each ciprofloxacin 74.2%, levofloxacin 50.8% and moxifloxacin 47.4%. In the results of dosage validation, the validities were each ciprofloxacin 54.8%, levofloxacin 94.9% and moxifloxacin 100.0%. In the results of duration validation, the validities were each ciprofloxacin 59.1%, levofloxacin 78.0% and moxifloxacin 89.5%. Adverse drug reactions were reported for total 49 cases and those were gastrointestinal tract effects including nausea, vomiting, diarrhea and central nervous system effects including headache, dizziness. In summary, the quinolones appropriately used for hospitalized patients based on this study. A focused approach emphasizing "correct use of quinolones" may reduce development of antimicrobial resistance and maximize class efficacy. Consequently, correct use of antibiotics will contribute to decrease medical expenses for person and community.

• Psychiatry investigation
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• 제15권11호
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• pp.1053-1063
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• 2018

Objective This study evaluated the psychometric properties of the Korean Anxiety Screening Assessment (K-ANX) developed for screening anxiety disorders. Methods Data from 613 participants were analyzed. The K-ANX was evaluated for reliability using Cronbach's alpha, item-total correlation, and test information curve, and for validity using focus group interviews, factor analysis, correlational analysis, and item characteristics based on item response theory (IRT). The diagnostic sensitivity and specificity of the K-ANX were compared with those of the Beck Anxiety Inventory (BAI) and Generalized Anxiety Disorder 7-item scale (GAD-7). Results The K-ANX showed excellent internal consistency (${\alpha}=0.97$) and item-total coefficients (0.92-0.97), and a one-factor structure was suggested. All items were highly correlated with the total scores of the BAI, GAD-7, and Penn State Worry Questionnaire. IRT analysis indicated the K-ANX was most informative as a screening tool for anxiety disorders at the range between 0.8 and 1.6 (i.e., top 21.2 to 5.5 percentiles). Higher sensitivity (0.795) and specificity (0.937) for identifying anxiety disorders were observed in the K-ANX compared to the BAI and GAD-7. Conclusion The K-ANX is a reliable and valid measure to screen anxiety disorders in a Korean sample, with greater sensitivity and specificity than current measures of anxiety symptoms.