• Korean Journal of Radiology
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• v.22 no.3
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• pp.354-365
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• 2021

Objective: To investigate the diagnostic performance of contrast-enhanced ultrasound (CEUS) and its role as a second-line imaging modality after gadoxetate-enhanced MRI (Gd-EOB-MRI) in the diagnosis of hepatocellular carcinoma (HCC) among at risk observations. Materials and Methods: We prospectively enrolled participants at risk of HCC with treatment-naïve solid hepatic observations (≥ 1 cm) of Liver Imaging Reporting and Data System (LR)-3/4/5/M during surveillance and performed Gd-EOB-MRI. A total of one hundred and three participants with 103 hepatic observations (mean size, 28.2 ± 24.5 mm; HCCs [n = 79], non-HCC malignancies [n = 15], benign [n = 9]; diagnosed by pathology [n = 57], or noninvasive method [n = 46]) were included in this study. The participants underwent CEUS with sulfur hexafluoride. Arterial phase hyperenhancement (APHE) and washout on Gd-EOB-MRI and CEUS were evaluated. The distinctive washout in CEUS was defined as mild washout 60 seconds after contrast injection. The diagnostic ability of Gd-EOB-MRI and of CEUS as a second-line modality for HCC were determined according to the European Association for the Study of the Liver (EASL) and the Korean Liver Cancer Association and National Cancer Center (KLCA-NCC) guidelines. The diagnostic abilities of both imaging modalities were compared using the McNemar's test. Results: The sensitivity of CEUS (60.8%) was lower than that of Gd-EOB-MRI (72.2%, p = 0.06 by EASL; 86.1%, p < 0.01 by KLCA-NCC); however, the specificity was 100%. By performing CEUS on the inconclusive observations in Gd-EOB-MRI, HCCs without APHE (n = 10) or washout (n = 12) on Gd-EOB-MRI further presented APHE (80.0%, 8/10) or distinctive washout (66.7%, 8/12) on CEUS, and more HCCs were diagnosed than with Gd-EOB-MRI alone (sensitivity: 72.2% vs. 83.5% by EASL, p < 0.01; 86.1% vs. 91.1% by KCLA-NCC, p = 0.04). There were no false-positive cases for HCC on CEUS. Conclusion: The addition of CEUS to Gd-EOB-MRI as a second-line diagnostic modality increases the frequency of HCC diagnosis without changing the specificities.

• Korean Journal of Radiology
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• v.23 no.1
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• pp.52-59
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• 2022

Objective: To investigate whether the diagnostic performance of CT angiography (CTA) could be improved by modifying the conventional criterion (anastomosis site abnormality) to diagnose hepatic artery occlusion (HAO) after liver transplantation (LT) in suspected patients with Doppler ultrasound (US) abnormalities. Materials and Methods: One hundred thirty-four adult LT recipients (88 males and 46 females; mean age, 52.7 years) with suspected HAO on Doppler US (40 HAO and 94 non-HAO according to the reference standards) were included. We evaluated 1) abnormalities in the HA anastomosis, categorized as a cutoff, ≥ 50% stenosis at the anastomotic site, or diffuse stenosis at both graft and recipient sides around the anastomosis, and 2) abnormalities in the distal run-off, including invisibility or irregular, faint, and discontinuous enhancement. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the conventional (considering anastomosis site abnormalities alone) and modified CTA criteria (abnormalities in both the anastomosis site and distal run-off) for the diagnosis of HAO were calculated and compared using the McNemar test. Results: By using the conventional criterion to diagnose HAO, the sensitivity, specificity, PPV, NPV, and accuracy were 100% (40/40), 74.5% (70/94), 62.5% (40/64), 100% (70/70), and 82.1% (110/134), respectively. The modified criterion for diagnosing HAO showed significantly increased specificity (93.6%, 88/94) and accuracy (93.3%, 125/134) compared to that with the conventional criterion (p = 0.001 and 0.002, respectively), although the sensitivity (92.5%, 37/40) decreased slightly without statistical significance (p = 0.250). Conclusion: The modified criterion considering abnormalities in both the anastomosis site and distal run-off improved the diagnostic performance of CTA for HAO in suspected patients with Doppler US abnormalities, particularly by increasing the specificity.

• Korean Journal of Radiology
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• v.2 no.4
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• pp.210-215
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• 2001

Objective: To investigate the efficacy of gadobenate dimeglumine (GdBOPTA) enhanced MR imaging for the detection of liver lesions in patients with primary malignant hepatic neoplasms. Materials and Methods: Thirty-one patients with histologically proven primary malignancy of the liver were evaluated before and after administration of GdBOPTA at dose 0.05 or 0.10 mmol/kg. T1-weighted spin echo (T1W-SE) and gradient echo (T1W-GRE) images were evaluated for lesion number, location, size and confidence by three off-site independent reviewers and the findings were compared to reference standard imaging (intraoperative ultrasound, computed tomography during arterial portography or lipiodol computed tomography). Results were analyzed for significance using a two-sided McNemar's test. Results: More lesions were identified on Gd-BOPTA enhanced images than on unenhanced images and there was no significant difference in lesion detection between either concentration. The largest benefit was in detection of lesions under 1 cm in size (7 to 21, 9 to 15, 16 to 18 for reviewers A, B, C respectively). In 68% of the patients with more than one lesion, Gd-BOPTA increased the number of lesions detected. Conclusion: Liver MR imaging after Gd-BOPTA increases the detection of liver lesions in patients with primary malignant hepatic neoplasm.

• Mass Spectrometry Letters
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• v.15 no.2
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• pp.79 -94
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• 2024

Over the past few decades, new psychoactive substances (NPS) have become prevailing. With the widespread emergence of NPS, phenethylamines (PEAs) have become one of the groups abused most which PEAs, along with other stimulants, make up the majority of stimulants. When determining the NPS, the methods for screening and confirmation are crucial which assesses the reliability of testimony. In this study, a set of GC/MS methods employing two derivatizing agents for determining 76 target PEAs in urine was established and further applied for authentic sample analysis. Five PEAs (N,N-DMA, PMMA, 4-CA, amphetamine, and methamphetamine) with contents over their LLOQs were detected in thirteen of the twenty tested samples. In order to compare the result from the GC/MS methods with the previously established LC-MS/MS method, Cohen's kappa coefficient and McNemar's test were applied for statistical analysis. Perfect agreement between GC/MS and LC-MS/MS techniques for determining target PEAs is demonstrated by the Kappa coefficient for each of the five detected targets.

• Safety and Health at Work
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• v.15 no.2
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• pp.164-171
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• 2024

Background: Telework adoption in Taiwan has surged because of government guidelines during the COVID-19 pandemic. This study examined the disclosure practices of Taiwanese-listed companies, assessing their adherence to government telework guidelines and their correlation with corporate governance, focusing on occupational health measures. Methods: We conducted a guideline-adherent cohort analysis of the 2020 and 2021 sustainability reports of 295 Taiwanese-listed companies. We assessed their disclosure of corporate measures for teleworking in alignment with two government guidelines, specifically occupational health measures. Using the McNemar test and general estimating equation analysis, we compared the 2020 and 2021 responses and examined their associations with corporate governance rankings. Results: Telework adoption increased significantly from 2020 to 2021, with 68% of companies reporting new work modes. The mentioning of government guidelines also increased to 67% by 2021. Companies with higher governance rankings were more likely to adopt online occupational health measures, including occupational health services (RR = 2.03; 95% CI = 1.41-2.94; p < 0.001) and mental health promotion activities (RR = 2.01; 95% CI = 1.06-3.82; p = 0.032), than those with low rankings. Although on-site and online occupational health services increased, home workspace assessments did not. Conclusion: Our findings highlight significant upward trends in the disclosure of telework measures following the issuance of government guidelines. Corporate governance is significantly associated with the implementation of occupational health measures. Amid the evolution of teleworking, both government guidelines and corporate governance have become essential for shaping work arrangements and ensuring workforce well-being.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.700-704
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• 2010

Background: For staging primary lung cancer, integrated positron emission tomography/computed tomography (PET/CT) imaging is popular. The purpose of this study was to evaluate the accuracy of PET/CT scanning in lymph nodal staging of lung cancer. Material and Method: We studied 48 patients who had received CT, PET/CT and pulmonary resections due to primary non-small cell lung cancer in our hospital between January 2006 and August 2009. Mediastinal lymph nodes were classified as superior mediastinal nodes, aortic nodes, inferior mediastinal nodes, or N1 nodes. We compared the power of CT and PET/CT for diagnosing pulmonary lymph nodes for each of the four types of nodes. Result: PET/CT was more sensitive than CT for all groups except inferior mediastinal nodes. However, the differences were not significant (McNemar's test: superior mediastinal nodes, p=0.109; aortic nodes, p=1.000; inferior mediastinal nodes, p=0.625, N1 nodes, p=0.424). Conclusion: The accuracy of PET/CT is similar to that of CT alone for staging lymph nodes. The two imaging modalities might be used as complementary, cooperative tools. We expect that integrated PET/CT will be found to be significantly mmore sensitive after more trials are done and more data is accumulated.

• Tuberculosis and Respiratory Diseases
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• v.56 no.5
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• pp.485-494
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• 2004

Background : To assess the effects of mDOT implementation on sputum smear conversion for AFB (Acid fast bacilli) positive pulmonary tuberculosis patients, modified Directly Observed Treatment (mDOT) was started on October $8^{th}$ 2001 at a health center in Seoul. mDOT was defined through weekly interviewing and supervising of a patient by a supervisor (doctor, nurse, or lay health worker). The sputum smear conversion of a mDOT group was compared with that of a self-medication (self) group. Methods : This study included 52 AFB positive pulmonary tuberculosis patients registered at a health center in Seoul between October $8^{th}$ 2001 and April $23^{rd}$ 2002. 24 and 28 patients were enrolled in the mDOT and self medication groups, respectively. Paired (1:1) individual matching, by gender, extent of disease, relapse and age-matching variables, was performed between the two groups, resulting in 20 paired matches. This prospective study was planned as an unblinded, non-randomized quasiexperimental pilot project. Outcomes were identified from results of sputum smear examinations for AFB in both groups at 2 weeks, and 1 and 2 months. The paired matching data were analyzed using the SAS program version 8.1 by McNemar test. Results : At the end of 2 weeks of treatment, the sputum smear conversion of the mDOT group was somewhat higher than that of the self medication group (78.57 vs. 50%, p-value=0.289), and after 1 month of treatment no statistically significant difference was shown between the two groups (83.33 vs. 50, p-value=0.125). At the end of 2 months of treatment (initial intensive phase), the sputum smear conversions of the mDOT and self groups were 95 and 75%, respectively (p-value=0.219). Conclusions : The implementation of mDOT did not result in clinically significant increases in the sputum smear conversion at 2 weeks, and 1 and 2 months compared with that of the self medication group. However, the increases experienced might contribute to diminishing the infectious period of AFB positive patients, and this approach may act as a guide for a specific group of patients. In this study, mDOT was performed for one hundred percent of the intensive treatment phase. It can also be an effective treatment for pulmonary tuberculosis patients, and may be useful for some high risk tuberculosis patients.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.3
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• pp.218-228
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• 2008

Purpose: Our purpose was to evaluate spinal bony metastasis which could be missed on an F-18 FDG PET/CT (FDG PET/CT) alone, and to characterize discordant metastatic lesions between FDG PET/CT and bone scan. Material and Methods: FDG PET/CT and bone scans of 43 patients with spinal bony metastasis were analyzed retrospectively. A McNemar test was performed comparing the FDG PET/CT alone to the FDG PET/CT plus bone scan in the spinal bony metastases. A one-way chi-square test was performed to characterize the metastases that were missed on the FDG PET/CT alone. To evaluate discordant lesions between FDG PET/CT and bone scan, we performed logistic regression analyses. The independent variables were sites (cervical, thoracic, and lumbar), size (large and small), and maximum SUVs, and the dependant variable was bone scan uptake (positive and negative MDP uptake). Results: A significant difference was found between the FDG PET/CT alone and the FDG PET/CT combined with the bone scan (p < 0.01). Using the FDG PET/CT only, diffuse osteoblastic metastasis was missed with a significantly higher frequency (p = 0.04). In the univariate analysis, cervical vertebra and small size were related to negative MDP uptake, and thoracic vertebra and large size were related to positive MDP uptake. However, in the multivariate analysis, only the large size was related to positive MDP uptake. Conclusion: A bone scan in addition to the FDG PET/CT increased the ability to evaluate spinal bony metastases, especially for diffuse osteoblastic metastasis. Large metastasis was related to positive bone scan uptake in spinal bony metastasis.

• Journal of radiological science and technology
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• v.37 no.3
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• pp.211-221
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• 2014

The clinical practices provide the students with a good opportunity to study the practical experiences in their field through the clinical training education in hospital. Now, in this study, comparing the perceptions of the clinic teachers with those of students at the clinical site. The study was conducted to the students attending universities located in Seoul and who finished the clinical practices in 2013. The questionnaires were distributed to the student and collected from them. The study were conducted to 275 questionnaires with frequency analysis, crosstabs, chi-square test and McNemar test. The major motivation was of the select radiography course was high employment rate(44.0%) and the satisfaction of radiography course was general(53.1%). 51.3% of the study answered 8 weeks current duration of clinical practices is proper. The 3-year course students answered that the period of clinical practices would be proper if it is performed in the winter vacation in their second year in college(47.3%). The 4-year course students answered that the first semester in their third years is proper for clinical practices( 27.7%). The students answered that they felt the lack in their knowledge on the professional field(32.4%) during the clinical practices and some of the practical training is different from the education performed at school(68.4%). Most of answered that they were satisfied with the clinical practices and among them they recognized the importance of the clinical practices ($3.94{\pm}0.89$). After the clinical practices, their desire for getting job as a radiography has changed from 84.1% to 82.9%. The reason why they want the job related to the radiation is because the job is stable (changed from 49.0% to 46.0% after the clinical practice) while the reason why they don't want be a radigrapher because that job is not proper for them (changed from 37.0% to 40.7% after the clinical practice) The effort should be made to enhance the position of radiation professionals through the improved education system to the students, rather giving them education for just employment.

• Journal of Korean Academy of Nursing Administration
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• v.1 no.2
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• pp.268-284
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• 1995

This study was designed to test effects of nursing ethics education (NEE) on moral reasoning and ethical decision making of subjects. This NEE that was teached for 10 hours course was composed of these : Nurses' ethical code, moral responsibility, Moral value and professional accountability, Respect for human life, General ethics, Theory and Norms of biomedical ethics, Ethical decision making model and Discussion about hypothetical ethical dilemmas Twenty-five senior student nurses were sampled from four year college of nursing from Nov. 3rd, 1993 to Nov. 24th, 1993. Data were collected through self-reported questionnaires included two kinds of tests. Rest's Defining Issues Test was adopted to measure the stage of moral development, which was classified with the stage 2 (instrumental relativist orientation), the stage 3 (interpersonal concordance), the stage 4 (law and order), the stage 5A (societal consensus), and the stage 5B (intuitional humanism), the stage 6 (universal ethical practice). In particular, the level of principled thinking (P) was measured by summing these scores of the stages 5A, 5B, and 6. The possible range of P is 0 to 95. As for measuring the levels of morality and nursing dilemma, Crisham's Nursing Dilemma Test was adopted. This test generated the morality score(MS) and the dilemma score (DS). The data were analyzed by t-test, ANOVA, Kruskal-Wallis test, Mc Nemar's test and Pearson correlation coefficients. The results were as follows ; 1. For the Moral Reasoning both before and after NEE, The Mean score of the stage 5A was significantly higher than that of other stages.(P=0.0001) Before NEE, the mean score of the stage 4 was significantly different from stage 2, 3, 5A, and after NEE, different from stage 2, 5B,6. 2. The analysis of change of moral development level revealed that the score of stage 4 increased after NEE.(P=0.0004) 3. The Effect of NEE for the mean score of 5A, 6, P after education was significantly different by birth place. 4. With regard to the five dilemmas postulated such as forcing medication performing cardiac pulmonary resuscitation, reporting a medication error, informing diagnosis to terminally ill adult, and providing new-nurse orientation, the mean score of the MS and the DS was no significant difference with general characteristics of the students. Effect of NEE morality score and dilemma score after education was no significant difference. 5. As for the correlations between moral reasoning and decision making, the score of the stage 2, 5A, 6, DS was positively correlated with the scores of before and after. Positive correlation was also observed between the scores of stage 2 and stage 4, stage 3 and 6. On the other hand, the score of P was negatively correlated with the scores of stage 2 and of stage 4 and of stage 5A. The score of the stage 5A was also negatively correlated with the score of the sge 6.