광중합형 수복용 복합레진의 인장강도에 미치는 thermal cycling과 시효 처리의 영향

백상현,채민수,이주형,김태조,배태성 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.1

The improvement in the mechanical properties of restorative composites has contributed to their increased use in recent years. In spite of their growing popularity, composites still have low resistance to fracture and wear in oral environments. This study was performed to examine whether the tensile strengths of light-cured restorative composites were affected by thermal cycling and aging in water. Five commerically available light-activated composites(Heliomolar : HM, Aelitefil : AF, Amelogen : AG, Clearfil AP-X : CF, Z100 : ZH) were used. Rectangular tension test specimens were fabricated in a teflon mold giving 5 mm in gauge length and 2mm in thickness. All samples were divided into 3 groups. Group 1 was stored in a desiccator for 10 days. Group 2 was immersed in a 37℃ distilled water for 10 days. Group 3 was subjected to 10,000 thermal cycles between 5℃ and 55℃, and the immersion time in each bath was 15 seconds per cycle. Tensile testing was carried out at a crosshead speed of 0.5 mm/min and fracture surfaces were observed with scanning electron microscope. The results obtained were summarized as follows; 1. The strength data fit to single-mode Weibull distribution(r²> 0.86) and Weibull parameters decreased after thermal cycling test. 2. The highest characteristics strength was observed in the CF group but the highest Weibull modulus was obtained in the AF group after thermal cycling test. 3. The highest tensile strength value of 83.92 MPa was obtained in the CF group and the lowest value of 13.91 MPa was obtained in the AG group. Tensile strengths showed no significant difference between HM and AG groups but other groups showed the significant differences in each group(p<0.05). 4. According to the microscopic observation of the fracture surfaces, fractures of large fillers were observed in the hybrid composites of the AF and CF groups.

오매(Fructus Mume)의 항산화물질의 분리 및 특성연구

황현주,안은미,백남인,조재선,김해영 경희대학교 생명자원과학연구원 1998 硏究論文集 Vol.19 No.-

천연물로부터 새로운 항산화제를 개발하기 위한 연구의 일환으로 한방에서 사용되는 한약재 중의 하나인 오매(烏梅)의 물 추출물과 메탄을 추출물 및 순차 분획물에 대해 팜유, 우지와 돈지를 기질로하여 유지저아시험, Rancumat method, 전자공여작용 등으로 항산화성을 확인한 결과, EtOAc 분획물에서 강한 항산화 활성을 나타내어 column chromatography, thin layer chromatography를 통하여 활성성분에 관한 연구를 시도하였다. 1. 오매 용매분획물 중 EtOAc 분획물(400 ppm)은 유지저장실험(60℃)에서, 팜유, 우지와 돈지에 모두 우수한 효과를 나타내었으며, 특히 우지에서 높은 활성을 나타내었고, BHA(200 ppm)와 α-tocopherol(200 ppm)보다 활성이 높았다. 2. 오매 EtOAc 분획물(400 ppm)은 Rancimat method에서는 팜유, 우지와 돈지에 비교적 우수한 효과를 나타내었으며, 우지에서 AI가 4.39로 상당히 높은 활성을 나타내었다. 3. 오매의 용매분획물 중 EtOAc 분획물이 DPPH라디칼에 대한 강한 소거활성을 나타내었으며, 그 활성은 EtOAc 분획물의 농도에 의존하여 증가하였고, SC_(50)은 21.2μg/ml이었다. 4. 오매 EtOAc 분획물에서 분리한 8개 획분 중 E4에서 SC_(50)이 16.7μg/ml으로 높은 DPPH 라디칼 소거활성을 나타내었으며, 원인 물질은 여러 가지 스펙트럼 측정 결과 수종 물질이 혼합물인 것으로 밝혀져, 보다 순수한 형태로의 분리 후 정확한 동정의 시도가 요구되었다. Fructus Mume is the roasted hits of Prunus mwme and has been used as tradibonal Chmese medicine. The anboxidatwe effect of the extract from Fructus Mume was measured using different methodsn such as, electron donating abdihes(EDA), Rancimat and oven tests. The methanol extract obtained from the Fructus Mume was solvent-fractionated with ethyl acetate, n-butanol and water, respectively. The ethyl acetate fraction showed the highest antioxidative activity among them. To identify the compounds with antioxidative activity, the isolates from thm layer chromatography were studied further. This study demonstrates that Fructus Mume might be useful for the prevention or treatment of disorders associated with oxidative damage.

학령전기 장애아 어머니의 부담감과 사회적지지

양경미,백영주,오현이 조선대학교 부설 의학연구소 2000 The Medical Journal of Chosun University Vol.25 No.1

Background and Objective : The purpose of this study is to identify the level of burden and social support of mothers who have handicapped children of preschool age, and is to determine whether providing social support is an effective strategy to relieve the burden of those mothers. Materials and Method : From August 17, to September 28, 1999, the data was collected from 83 mothers caring handicapped children of preschool age, who are being treated and educated at two welfare centers for the handicapped, two early training and treating centers for them in Kwangju, and one center in Seoul. Two instruments used in this study were the burden scale developed by Suh and Oh, and the Personal Resource Questionnaire(PRQ, Part Ⅱ) developed by Brandt and Weinert. The data was analyzed with t-test, ANOVA, Scheffe’s test, Pearson’s Correlation Coefficient, and Stepwise Multiple Regression analysis. Results : 1. The correlation between the burden and the social support was statistically significant. 2. Sorts of handicap of children was the most important predictor to burden of mothers caring handicapped children of preschool age(R2=.20). In addition to, this social support and brother’s precedence accounted for 32% of burden of those mothers. Conclusion : There was significant negative correlation between social support and burden.

근적외분광분석법을 이용한 참기름 정량 분석 및 진위 판별

서은정,백주현,우영아,김효진 동덕여자대학교 종합약학연구소 2002 동덕약학연구지 Vol.6 No.-

In this study, sesame oil have been analyzed by near infrared spectroscopy (NIRS). Sesame oil was mixed with the other edible oil. NIR transmittance spectra of sesame oil mixtures were acquired by using a dip probe. Partial least squares regression (PLSR) was applied to develop a calibration model over the spectral range 1100-1750nm. The calibration model predicted the content of sesame oil for validation set with a standard errors of prediction (SEP) of 0.3871%. Soft Independent Modeling of Class Analogy (SIMCA) was used to identify sesame oil and adulteration. This model identified the sesame oil and adulteration for validation set with 100% accuracy. This study showed that the rapid and non-destructive the determination of the quantitative analysis of sesame oil, the identification of sesame oil and adulteration was successfully performed by portable NIR system.

신생검증례에 의한 사구체신질환의 분석

최두환,구시선,배승훈,박병현,안선호,송주흥 圓光大學校 醫科學硏究所 1996 圓光醫科學 Vol.12 No.2

To elucidate the incidences and the clinical characteristics of glomerular diseases in our hospital, we reviewed the clinical records and histological findings of the 117 cases, which were diagnosed as one of the glomerular disease in renal biospy for about 6 years since 1991. In these 117 cases, 74 cases (63.2 %) fell into primary glomerulonephritis(GN), 18 cases (15.4%) into secondary GN, 2 cases (1.7 %) into end stage kidney, 4 cases (3.4%) into tubulointerstitial disease and the biopsy samples were inadequate for diagnosis in 19 cases. In primary glomerular diseases, most common pathologic diagnosis was IgA nephropathy (36.5 %}, followed by minimal change nephrotic syndrome (29.7%). The incidence of IgA nephropathy would be increased if we had biopsied every asymptomatic urinary abnormality (AUA) patients. Systemic lupus erythematosus (SLE) . hepatitis B accounted for most of secondary GN in our cases. One case of progressive scleroderma was included in this secondary GN. Minimal change nephrotic syndrome (22 cases) was the most common cause of nephrotic syndrome, followed by membranous GN (9 cases) and IgA nephropathy (8 cases). 2 cases of primary amyloidosis were presented with nephrotic syndrome. Nephrotic syndrome as presenting symptom in our IgA nephropathy patients was higher than in other studies, which may be due to indication bias for renal biopsy. We suggest that renal biopsy should be done in adult nephrotic syndrome and in SLE, because various kind of glomerular diseases can develop nephrotic syndrome in adult, renal biopsy can affect the treatment and prognosis in each patients and renal biopsy also determines the extent of renal involvement in SLE on which the treatment depends. In AUA urinary patients, renal biopsy could be reserved for the patients who show declining of GFR or rising of proteinuria. Because IgA nephropathy account for most of AUA. and there is no specific treatment for IgA nephropathy, and renal biopsy in those cases is helpful in ruling out the patients who need no treatment.

간 세포암에서 VEGF, TGF-β1, b-FGF 발현의 의의

김성용,남충현,주종우,채만규,백무준,이문수,김형철,안현철,김홍수,김창진,김창호 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.1

Purpose: Angiogenesis is important for the proliferation and the metastasis of solid tumors. The growth of a solid tumor is widely recognized to depend on the process of neovascularrozation. Without angiogenesis, tumors cease to grow beyond even a few milimeters in diameter. It has been shown that tumor vascular density is an independent prognostic marker in several types of human tumors and is known to correlate with poor prognosis. To date, many angiogenic factors have been identified, such as transforming growth factor-α(TGF-α), transforming growth factor-β(TGF-β), fibroblast growth factor family(FGF), vascular endothelial growth factor(VEGF), platelet derived endothelial cell growth factor(PD-ECGF), tumor necrosis factor-α(TNF-α), and angiogenin. Hepatocellular carcinoma(HCC) is the second most common tumor in Korean males and is known as a typical hypervascular tumor with frequent portal vein invastion. The authors identified the expreesion of VEGF, TGF-β1, and b-FGF in HCC specimens and evaluated the relationship between these growth factors and the clinicopathologic characteristics of HCC. Method: We reviewed the medical records of 30 patients who were diagnosed as hepatocellular carinoma treated with hepatic resection between January 1994 and December 1998 in Soonchunhyang University Chunan Hospital. The selection of the cases was decided according to the condition of paraffin block fixation. The prognostic factors such as age, sex, tumor size, concentration of serum α-fetoprotein, presence of liver cirrhosis, presence of tumor emboli in portal vein, TMN stage, amount of transfusion during the operation, hepatitis B virus(HBV) infection, and Edmonson-Steiner(E-S) grade were investigated. Relationship between the prognostic factors and the immunopathologic expression of the TGF-β1, b-FGF, and VEGF was examined. Result: Thirty patients (24 males, 6 females) were included in the current study. The patient's mean age was 50.6 years and the age ranged from 36 to 65 years. The mean size of the tumor was found to be 5.2cm. All the patients were follewed up for 7 to 63 months. Child's classification A patients were 23(76.7%)cases, B patients were 7(23.3%)cases, and C was none. Immunohistochemical staining of HCC tumor mass in VEGF expression patients were 17(56.7%), b-FGF expression patients were 10(33.3%), and TGF-β1 expression patients were 10(33.3%). VEGF expression or more than one positive expression among the three factors correlated with tumor size and the stage of HCC but did not correlated with other clinicopathological characteristics. TGF-β1 and b-FGF did not correlate with any clinicopathological characteristics. Conclusion: The results suggest that the expression of VEGF or more than one positive expression among the three factors in HCC cells may be a significant prognostic factor of HCC.

노화와 간경변이 인체의 적혈구, 혈장 및 위 점막의 Glutathione 농도와 Glutathione Peroxidase 활성도에 대해 미치는 영향

백광호,김종혁,백일현,한태호,박현주,박상훈,서중산,박충기,유재영 대한노인병학회 2001 대한노인병학회지 Vol.5 No.3

2003년 국내 중증급성호흡기증후군 진료 현황 및 문제점 분석

이진수,김은실,정문현,백제중,정선화,안주희,최영화,이선희,고철우,김성범,김민자,박승철,기현균,송재훈,최상호,김양수,이상오,조용균,박영훈,정숙인,김연숙,이흥범,손창희,장성희,정희진,김우주 대한감염학회 2004 감염과 화학요법 Vol.36 No.3

목적 : 2002년 말 중국에서 SARS가 발생한 이후 국내에서도 2003년 10월까지 총 3명의 추정환자, 17명의 의심환자가 보고되었다. 향후 추가적인 SARS의 유행이 우려되는 상황에서, 그간의 SARS 환자 진료에 있어서의 실질적인 준비사항, 진료 현황 등에 대한 조사를 통해 문제점을 파악하여, 향후 더 나은 대비가 될 수 있도록 개선점을 제시하고자 하였다. 재료 및 방법 : SARS로 의심되는 환자를 진료 경험이 있는 병원의료진을 대상으로 2003년 10월에 설문조사를 실시하였다. 설문에는 SARS 환자 진료 시의 실질적인 조치, 진료 현황, 병실, 응급실 및 외래에서의 격리 시설과 준비사항, 보건당국의 관리와 지원에 관한 사항을 포함하였다. 결과 : 대상이 되는 22개 병원 중 17개(17/22, 77.2%) 병원이 설문에 응하였다. SARS 환자를 위한 격리실은 응급실, 외래, 일반병실 및 중환자실에서 각각 9개(9/17, 52.9%), 5개(5/17, 29.4%), 15개(15/16, 93.7%), 4개(4/16, 25%) 병원에서 음압처리가 되어있지 않은 일인실 혹은 다인실이 사용되었고, 1개(1/16, 6.3%) 병원에서만 일반병실에서 음압격리실이 운영되었다. 입원환자의 진찰 시 개인보호구의 착용은 거의 모든 의료기관에서 이루어졌다. 보건당국에서 SARS지정병원의 시설 등을 사전에 확인한 곳은 1곳(1/12, 8.3%)이였고, 14개 병원(14/15, 93.3%)에서는 보건당국에 의뢰한 검사결과를 통하 받지 못하였다. 결론 : 의료기관에서 SARS 환자용 격리실뿐만 아니라 기존의 격리실 설비 등이 미흡하였으며, 특히 중환자실 및 외래의 준비가 더욱 부족하였다. 보건당국의 의료기관에 대한 종합적인 지원이 부족하였고, 병원과의 원활한 연계가 잘 이루어지지 않았다. SARS 만이 아닌 격리를 필요로 하는 질환의 적절한 진료를 위해 향후 병원 시설의 정비와 정부차원에서의 보다 구체적이고 실질적인 대책마련이 필요하다. Background : There was an worldwide outbreak of the Severe Acute Respiratory Syndrome (SARS) originated from China in late 2002. During that period three cases of suspected SARS and 17 cases of probable SARS were reported in Korea. With the concerns about the reemergence of SARS-coV transmission, it is important to be prepared for any possibility. So, this study is aimed to analysis the past measures in managing SARS and propose the amendatory plans to improve the preparedness. Materials & Methods : Questionnaires were collected among clinicians with any experience in managing the probable or suspected SARS cases in Oct. 2003. 17 out of 22 hospitals responded to the questionnaire. The contents in the questionnaire were practical activities, personal equipments, response plans, isolation facilities in emergency centers, outpatient clinics, general wards and intensive care units, and relationship with the public health department. Results : The dedicated isolation rooms in emergency centers, outpatient clinics, general wards, and intensive care units were prepared in 9 (9/17, 52.9%), 5 (5/17, 29.4%), 15 (15/16, 93.7%), and 4 (4/16, 25.0%) hospitals, respectively. Except for one hospital that newly made negative pressure room for SARS, single or multi-bed rooms without airborne infection control were used in all the other hospitals. The personal precaution principles were kept quite well in general wards. Before the designation of SARS hospital by the public health department prior evalution to see if the hospital was suitable for managing SARS was conducted in only 1 (1/12, 8.3%) hospital. The results of laboratory diagnosis were reported back in 1 (1/15, 6.6%) hospital. Conclusions : The isolation facilities which can control airborne infection were almost deficient not only for SARS but also for other respiratory transmissible diseases. For the infection control of transmissible diseases including SARS, more investment is needed on medical facilities and comprehensive support from the public health department required.

Biological Activities of Methyl-4-[[(2E)-3,7-dimethyl-oxy]-3-hydroxybenzoate

Baek, Seung-Hwa,Oh, Hyun-Ju,Lim, Jin-A,Chun, Hyun-Ja,Lee, Hyun-Ok,Ahn, Jong-Woong,Perry, Nigel B.,Kim, Hyung-Min Korean Chemical Society 2004 Bulletin of the Korean Chemical Society Vol.25 No.2

Methyl-4-[[(2E)-3,7-dimethyl-2,6-octadienyl]oxy]-3-hydroxybenzoate (5) has been identified from the New Zealand liverwort Trichocolea hatcheri (T. hatcheri) on the basis of spectroscopic evidence. This compound was tested for its growth inhibitory effects against tumor cell lines, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. It showed growth inhibition activity against Staphylococcus epidermidis (MIC, 1,000 ${\mu}$g/mL). These results suggest that compound 5 possesses antitumoral , antimicrobial and antioxidative activities.

A GaAs Micromachined Millimeter-wave Lowpass FilterUsing Microstrip Stepped-Impedance Hairpin Resonator

Ju-Hyun Cho,Tae-Soon Yun,Ki-Byoung Kim,Tae-Jong Baek,Baek-Seok Ko,Dong-Hoon Shin,Jong-Chul Lee 한국ITS학회 2004 한국ITS학회 학술대회 Vol.2004 No.1