Original Articles : Clinical significance of occult hepatitis B virus infection in chronic hepatitis C patients

( Jae Young Jang ),( Soung Won Jeong ),( Sung Ran Cheon1 ),( Sae Hwan Lee1 ),( Sang Gyune Kim ),( Young Koog Cheon ),( Young Seok Kim1 ),( Young Deok Cho1 ),( Hong Soo Kim ),( So Young Jin ),( Yun Soo 대한간학회 2011 Clinical and Molecular Hepatology(대한간학회지) Vol.17 No.3

Background/Aims: We investigated the frequency of occult hepatitis B virus (HBV) infection in anti-hepatitis C virus (HCV)-positive individuals and the effects of occult HBV infection on the severity of liver disease. Methods: Seventy-one hepatitis B virus surface-antigen (HBsAg)-negative patients were divided according to their HBV serological status into groups A (anti-HBc positive, anti-HBs negative; n=18), B (anti-HBc positive, anti-HBs positive; n=34), and C (anti-HBc negative, anti-HBs positive/negative; n=19), and by anti-HCV positivity (anti-HCV positive; n=32 vs. anti-HCV negative; n=39). Liver biopsy samples were taken, and HBV DNA was quantified by real-time PCR. Results: Intrahepatic HBV DNA was detected in 32.4% (23/71) of the entire cohort, and HBV DNA levels were invariably low in the different groups. Occult HBV infection was detected more frequently in the anti-HBc-positive patients. Intrahepatic HBV DNA was detected in 28.1% (9/32) of the anti-HCV-positive and 35.9% (14/39) of the anti-HCV-negative subjects. The HCV genotype did not affect the detection rate of intrahepatic HBV DNA. In anti-HCV-positive cases, occult HBV infection did not affect liver disease severity. Conclusions: Low levels of intrahepatic HBV DNA were detected frequently in both HBsAg-negative and anti-HCV-positive cases. However, the frequency of occult HBV infection was not affected by the presence of hepatitis C, and occult HBV infection did not have a significant effect on the disease severity of hepatitis C. (Korean J Hepatol 2011;17:206-212)

온라인 전자 지도안 시스템의 구축 및 활용에 관한 연구

천종필,백장미,한선관,이철환 한국컴퓨터교육학회 2003 컴퓨터교육학회 논문지 Vol.6 No.1

본 연구자들은 ICT 활용 교육을 위한 초등교육 지도안을 온라인상에서 작성하고 활용할 수 있는 Web기반 전자지도안 시스템을 개발하였다. 개발된 온라인 전자지도안 시스템 은 ICT 교수-학습 과정안 자료를 데이터베이스화하여 체계적으로 관리할 수 있도록 하였으며, 교수-학습 과정안의 공유, 활용, 저장성의 극대화를 도모하여 학교 정보화에 이바지할 수 있다. 이렇게 개발된 시스템이 현장에서 활용되면서 나타난 교육적 효과 및 문제점을 분석하여 해결 방안을 제시하는 것은 시스템의 개발 못지않게 중요하다고 할 수 있다. 따라서 본 연구에서는 첫째, 본 시스템 개발을 위한 ICT 활용 교수·학습 과정안 형태의 구안과정과 둘째, 본 시스템의 설계와 구현 방법의 개요, 그리고 셋째, 초등학교 현장에서 적용하면서 나타난 시스템의 효과와 문제점 분석 및 개선방안을 제시하였다 또 연구를 통하여 초등교육에서 사용하게 될 전자 교육 시스템의 개발 과정 및 활용 상의 고려사항과 문제점의 해결 방안에 대한 교육적 근거를 제공하였다. The researchers developed On-line Lesson Planner System so that teachers can make a lesson plan using ICT(Information & Communication Technology) on line. Developed On-line Lesson Planner System can make ICT using lesson plans store in the database, manage them systematically and help maximize share, use and storage of the lesson plans. It can contribute to the school informatization. It is important to suggest solution through analyzing the educational effects and problems appeared during applying to this developed system in real fields. Thus, this study suggests first, procedure of designing the lesson plan using ICT for the development of this system, second, the summary of designing and embodying methods, and third, the improvement and analysis of the effects and problems revealed in elementary school fields. This study provided educational grounds of the solution to the problems and consideration of this On-line Lesson Planner system.

채널 식각형 비정질 실리콘 박막 트랜지스터에서 배면에 수소 이온 도핑효과

장진,최종현,이경하,임병천,김창수 慶熙大學校 레이저 工學硏究所 1997 레이저공학 Vol.8 No.-

We have studied the effect of the hydrogen ion doping on the free surface of back channel etched a Si:H TFTs. The hydrogen ion doping on the back channel etched TFT reduces the off-state photo leakage current by one order of magnitude. The reduction of the photo-leakage current is due to the creation of defect states at the free surface by hydrogen ion doping. After hydrogen ion doping on the free surface, the field effect mobility change little, but the threshold voltage increases, which is due to the state creation in a-Si:H by ionized H ions. Furthermore, the off-state leakage current under frontlight illumination can be reduced by 2 orders magnitude by hydrogen ion doping on the back channel of a Si:H TFT.

MHC class Ⅰ분자들에 의해 제시되는 Epitope을 인지하는 CD8+ T림프구의 결핵균 감염에 대한 면역반응의 연구 : 결핵환자와 PPD+ 건강개체에 존재하는 결핵균 항원에 특정한 CD8+ T세포 Evidence of M. tuberculosis Specific CD8+ T Cells in TB Patients and PPD+ Healthy Individuals

조장은,이경화,박승규,천선희,조상래,조성애 Official Journal of the Korean society for immunol 2003 Immune Network Vol.3 No.3

VLSI 구현을 위한 Motion Estimation 알고리즘의 비교 분석

安長天,柳在熙 弘益大學校 科學技術硏究所 1996 科學技術硏究論文集 Vol.7 No.2

Motion estimation has been chosen for the major image compression standards such as CCITT, MPEG 1,2 and 4 because of the efficiency of temporal redundancy elimination even though it requires a great amount computations and hardware. Many motion estimation algorithms proposed so far have lots of trade off's among performances, VLSI implementation and computation amounts, which should be carefully considered to select the best algorithm for each application area. Therefore, this paper analyzes and compares motion estimation algorithms, which are full search block matching, hierarchical block matching using block subsample as well as pel subsample in a block and the subsample with a low pass filter. The performances such as mean square error, pick to pick signal to noise ratio and the computation amount are simulated using C-code and their results are described and compared. Finally, the reconstructed images based on the four motion estimation algorithms are shown for eye ball tests.

한국어 자동색인 시스템 설계에 관한 연구

정천영,장수진,진성일 충남대학교 자연과학연구소 1992 忠南科學硏究誌 Vol.19 No.1

The purpose of this paper is to suggest an automatic indexing system for Korean documents with an auxiliary word and the ending of a word in thesis. This system is structured with an auxiliary word dictionary, a negative dictionary, a declinable word list and an abbreviation dictionary. In this thesis, we suggest methods to analyze short clauses, remove negative words, restore abbreviations to original words and extract compound phrases.

방화석고보드 두께 및 접착방식 변화에 따른 고강도 콘크리트의 폭렬특성

한천구,배장춘,장기현 청주대학교 산업과학연구소 2008 産業科學硏究 Vol.26 No.1

This study investigates fire resistance properties of high strength concrete designed with various thickness and adhesive methods of fireproof gypsum board. Test results showed that compressive strength of control concrete indicated 89.9MPa, which is high strength rage. For the fire test results, uncovering top section of specimens caused severe spalling occurrence in all sides, exposing mostly re-bars. Moreover, some specimens even exposed main bars of concrete. However, covering top section of specimens protected from fire and resulted in secured high strength concrete. The maximum temperature of main bars in 19BN-W indicated 1017℃, in 19MB-W was 1061℃, in 19MN-W was 1036℃, in 25MB-W was 583℃ and in 19MN-T was 271℃ respectively. 19MB-W had the highest value of weight loss ratio, indicating 54%, while 25MB-W showed 43% of weight loss ratio, 19BN-W was around 40%, 19MN-W was around 27% and 19MN-T was around 7%.

새열기형의 임상적 고찰

김장묵,김대식,백승혁,한동렬,김희중,백병준,오천환 순천향의학연구소 2000 Journal of Soonchunhyang Medical Science Vol.6 No.2

Background and Objectives : Branchial cleft anomalies are encountered rarely in clinical practice. We reviewed medical records of branchial cleft anomalies according to age and sex distribution, site distribution, characteristics of mass on physical examination, location of mass, preoperative diagnosis, type of branchial cleft cyst and report our experience with 25 cases of branchial cleft anomalies. Materials and Methods : A review of medical records was performed on 25 cases of branchial cleft anomalies diagnosed in pathologic report from January, 1990 to March, 2000. Result : Sex distribution was 11 male and 14 female, age distribution was most common in third decade which was 8 cases(32%). Site distribution was predominant in left side(13 cases), and in physical examination, the characteristics of the mass was nontender(76%), mobile(60%), soft(80%). The lesion site was submandibular area in 2 cases, upper 1/3 portion of sternocleidomastoid muscle(SCM) in 2 cases, middle 1/3 portion of SCM in 20 cases and parotid area in 1 case. The preoperative diagnosis was branchial cleft cyst in 16 cases, cervical lymphadenitis in 3 cases, tuberculous lymphadenitis in 3 cases, branchial cleft fistula in 1 case, dermoid cyst in 1 case and parotid mass in 1 case. Among 25 cases, first branchial cleft cyst was seen in 4 cases, second branchial cleft cyst in 20 cases and second branchial cleft fistula in 1 case. Conclusion : The clinical history of recurrent neck inflammatory episodes in young patients and nontender, mobile, soft neck mass should raise the suspicion of this entity. Investigation using CT scanning in combination with aspiration is useful. Treatment of all branchial cleft anomalies is complete surgical excision because there is lack of spontaneous regression, a high rate of recurrent infection, the possibility of other diagnosis, and rare malignant degeneration. Complete removal without complications depends on a good understanding of regional embryogenesis, a knowledge of the surrounding structure, and awareness of the different anatomical presentation.

교맥 에탄올 추출물의 멜라닌생성 억제효과

김대성,노성택,이장천,임규상,신미란,우원홍,문연자 한국전통의학연구소 2006 한국전통의학지 Vol.15 No.1

The aim of this study was to investigate the effect of ethanol extract of Fagopyrum escuentum(FE) on the melanogenesis. To determine whether ethanol extract of FE suppress melanin synthesis in cellular level, B16F10 melanoma cells were cultured in the presence of different concentrations of FE ethanol extract. In the present study, the author examined the effects of FE ethanol extract on cell proliferation, melanin contents, tyrosinase activity. Cell proliferation was slightly increased by treatment with ethanol extract of FE (25-200 ㎍/ml). The ethanol extract of FE effectively suppressed melanin contents at a dose of 100 ㎍/ml. It was observed that the color of cell pellets was totally whitened compared with the control. The ethanol extract of FE inhibited tyrosinase activity, regulate melanin biosynthesis as the key enzyme in melanogenesis. These results suggest that the ethanol extract of FE exerts its depigmenting effects through the suppression of tyrosinase activity. And it may be a potent depigmetation agent in hyperpigmentation condition.

부비동 악성 종양의 임상적 분석

백병준,유명상,신재민,김효진,박훈,김장묵,오천환 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.2

Background and Objectives : Paranasal sinus cancer is rare when compared with cancers of other sites. Because paranasal sinus is anatomically located adjacent to the orbit and skull base, it is difficult to remove the tumor completely with tumor free margin in advanced paranasal sinus cancer. This report was conducted to investigate clinical characteristics, histologic type and treatment outcome of paranasal sinus cancer. Material and Methods : Twenty-six cases with paranasal sinus cancer diagnosed at the Department of otolaryngology-Head and Neck Surgery, Soonchunhyang Cheonan Hospital from January 1991 to September 2000 were studied by chart review, telephone interview and letters retrospectively. Results : The male to female ratio was 4.2 : 1. Most patients were 6th and 7th decade. The maxillary sinus was the most commonly affected site(61.5%), followed by the ethmoid sinus(34.6%). The most common histologic type of malignancy was squamous cell carcinoma(57.6%), followed by adenocarcinoma(19.2%). Most patients presented with T_(3)/T_(4) or locally advanced disease, N_(0)(91.3%), and M_(0)(100%) Sixtynine pertcent of this study group underwent sugery as part of a mutimodality curative treatment plan or alone as curative treatment. Eighteen patients(69.2%) developed recurrent disease at a median time of 278 days after initial treatment. Kaplan-Meier analysis revealed the 5-year disease specific survival was 34.6%. Conclusion : Most patients with paranasal sinus cancer presented with locally advanced disease. Adanced T stage was highly predictive of poor prognosis. Recurrence rate was high and mostly occured within the second year after treatment.