http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Seo, Minkook,Choi, Yangsean,Lee, Song,Kim, Bum-soo,Jang, Jinhee,Shin, Na-Young,Jung, So-Lyung,Ahn, Kook-Jin Korean Society of Magnetic Resonance in Medicine 2020 Investigative Magnetic Resonance Imaging Vol.24 No.1
Background: Differentiation of cerebellopontine angle (CPA) schwannoma from meningioma is often a difficult process to identify. Purpose: To identify imaging features for distinguishing CPA schwannoma from meningioma and to investigate the usefulness of susceptibility-weighted imaging (SWI) in differentiating them. Materials and Methods: Between March 2010 and January 2015, this study pathologically confirmed 11 meningiomas and 20 schwannomas involving CPA with preoperative SWI were retrospectively reviewed. Generally, the following MRI features were evaluated: 1) maximal diameter on axial image, 2) angle between tumor border and adjacent petrous bone, 3) presence of intratumoral dark signal intensity on SWI, 4) tumor consistency, 5) blood-fluid level, 6) involvement of internal auditory canal (IAC), 7) dural tail, and 8) involvement of adjacent intracranial space. On CT, 1) presence of dilatation of IAC, 2) intratumoral calcification, and 3) adjacent hyperostosis were evaluated. All features were compared using Chi-squared tests and Fisher's exact tests. The univariate and multivariate logistic regression analysis were performed to identify imaging features that differentiate both tumors. Results: The results noted that schwannomas more frequently demonstrated dark spots on SWI (P = 0.025), cystic consistency (P = 0.034), and globular angle (P = 0.008); schwannomas showed more dilatation of internal auditory meatus and lack of calcification (P = 0.008 and P = 0.02, respectively). However, it was shown that dural tail was more common in meningiomas (P < 0.007). In general, dark spots on SWI and dural tail remained significant in multivariate analysis (P = 0.037 and P = 0.012, respectively). In this case, the combination of two features showed a sensitivity and specificity of 80% and 100% respectively, with an area under the receiver operating characteristic curve of 0.9. Conclusion: In conclusion, dark spots on SWI were found to be helpful in differentiating CPA schwannoma from meningioma. It is noted that combining dural tail with dark spots on SWI yielded strong diagnostic value in differentiating both tumors.
( Dongsub Jeon ),( Minkook Son ),( Jonggi Choi ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.5
Background/Aims: The impact of liver cirrhosis (LC) on the clinical outcomes of patients with coronavirus disease 2019 (COVID-19) remains elusive. This study evaluated the association between LC and the development of severe complications from COVID-19. Methods: We used the National Health Insurance claims data of Korea. We included 234,427 patients older than 19 years who tested for severe acute respiratory syndrome coronavirus 2. Patients with LC who were infected with COVID-19 (n = 67, LC+ COVID+) were matched with those with cirrhosis only (n = 332, LC+ COVID-) and those with COVID-19 only (n = 333, LC- COVID+) using a propensity score in a 1:5 ratio. The primary outcome was the development of severe complications. Results: Of the matched patients, the mean age was 60 years and 59.7% were male. Severe complications occurred in 18, 54, and 60 patients in the LC+ COVID+, LC+ COVID-, and LC- COVID+ groups, respectively. After adjusting for comorbidities, there was no significant difference in the risk of developing severe complications from COVID-19 between the LC+ COVID+ and LC- COVID+ groups but significant difference exists between the LC+ COVID+ and LC+ COVID-. Older age, hypertension, cancer, chronic obstructive pulmonary disease, and a higher Charlson comorbidity index were associated with a higher risk of severe complications in patients with cirrhosis and COVID-19. Conclusions: Our study suggests that LC was not independently associated with the development of severe complications, including mortality, in patients with COVID-19. Our results need to be evaluated through a large, prospective study.
한국인(Kookin Han),최세완(Sewan Choi),김민국(Minkook Kim) 전력전자학회 2010 전력전자학술대회 논문집 Vol.2010 No.7
본 논문에서는 5㎾급 연료전지 응용을 위한 3상 DC-DC 컨버터를 제안한다. 제안한 컨버터의 Delta-Wye 결선은 전압형의 가장 큰 단점인 변압기 턴비를 최소화 하였으며 클램프 스위치의 동작으로 전압 및 전류 공진을 감소시키고 순환전류를 리셋시켜 각 소자들의 전류정격을 줄였다. 기존 3상 Full-Bridge와 비교 분석을 수행하였으며 시뮬레이션을 통해 타당성을 검증하였다.