Algal bioassay 에 의한 조류생장 제한영양염류 결정

오희목(Hee Mock Oh),이석준(Seog June Lee),김성빈(Seong Bin Kim),박미경(Mi Kyung Park),윤병대(Byung Dae Yoon),김도한(Do Han Kim) 한국하천호수학회 1998 생태와 환경 Vol.31 No.2

Determination of Limiting Nutrient for Algal Growth by Algal Bioassay. Oh, Hee-Mock, Seog June Lee, Seong-Bin Kim, Mi- Kyung Park, Byung-Dae Yoon and Do-Han Kim (Environmental Microbiology Research Unit, Korea Research Institute of Bioscience and Biotechnology, Taejon 305-333, Korea and Water Resources Research Institute, Korea Water Resources Corporation, Taejon 305-390, Korea) Water quaiity and algal growth potential (AGP) using Microcystis aeruginosa were investigated from April to September 1997 in Daechung Reservoir. Secchi disk transparency was 1.1 m in August. Chlorophyll-a concentrations were higher than 10㎍/l at all samples. Total phosphorus concentration was in a range of 0.020∼0.027mg/l which is at the approximate value of 0.03 mg/l, the general critical level of eutrophication. These results indicate that Daechung Reservoir is in an eutrophic state except some temporary times and restricted sites. Phosphorus uptake rate of M. aeruginosa was higher in the water from the epilimnion than in the hypolimnion and also higher under light condition than under dark condition. Therefore, phosphorus uptake rate appears to depend on cellular phosphorous content and light condition, a meaning of endergonic process. Phosphorus was the most frequently limiting nutrient: phosphorus was limiting algal gowth in April and May, nitrogen, phosphorus and trace elements were the limiting factors for algae in August, and trace elements in September. If a fast growing alga, M, aeruginosa, is used as a test organism for assaying AGP, in vivo fluorescence instead of dry weight can be measured for algal biomass and incubation period can be reduced from traditional 14 days to 7 days.

퍼머제의 중금속 농도에 관한 연구

윤복연,문덕환,박명희,황용식,함성애,손병철,김대환,이창희,김휘동,이채언 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.5

Objective : This study was conducted to prepare the fundamental data on heavy metal concentration in hair permanents agents and to prevent the health impairment due to heavy metal. Methods and Material : The author determined of 5 heavy metals(Pb, Cr, Mn, Ni, and Cu) concentration hair permanent agents in the market with flameless atomic absorption spectrophotometer. Results : The results were as follows: 1. The geometic mean concentrations of total subjects were 0.04㎍/g for Pb, 0.09㎍/g for Cr, 0.06㎍/g for Mn, 0.03㎍/g for Ni, and 0.04㎍/g for Cu. 2. The most highest mean concentrations of heavy metals in hair permanent agents by using type were Cr for wave agent and straight cream agent, Cu for setting iron agent, Cr and Cu for coating perm agent. 3. Metal most hlghest mean concentrations of heavy in hair permanent agents by type of color was green for Cu. 4. The mean concentration of Cu among 5 heavy metals in hair permanent agents by marker was most highest. 5. There was most statistically significant difference on mean concentration in hair permanent agents between domestic and foreign products. 6. The exposure amount of heavy metal concentration by one time using the permanent agent were 4.O㎍ for Pb, 9.O㎍ for Cr, 6.0㎍ for Mn, 3.O㎍ for Ni and 4.0㎍ for Cu. Conclusion : As above results author suggest to prepare the preventive program of health impairment due to heavy metal by long term chronic exposure to who were using the hair permanent agents hair designer and customers.

햄스터 oval cell의 간흡충감염 후 담관암으로의 분화에 관한 세포병리학적 연구

윤병일,김방현,김대용 한국수의병리학회 2002 한국수의병리학회지 Vol.6 No.1

Oval cell is considered as facultative precursor cells for both hepatocytes and biliary cells, as well as origin of hepatocellar and cholangiocellular carcinoma (CCC) during carcinogenesis or toxic liver injury. To clarify the cellular origin or differentiation of cholagiocarcinogenesis, the fate of carcinogen-induced oval cells was pathologically and phenotypically chased in Syrian golden hamster liver after Clonorchis sinensis (CS) infection which would give rise to a promoting effect. Two week treatment of hamsters with 0.005% diethylnitrosamine (DEN) followed by 2 week treatment of 1% 2-acetylaminofluorene (AAF) under choline deficient diet resulted in massive proliferation of BrdU labeled and PCNA positive oval cells showing various distinct morphology, histochemical and immunohistochemical phenotypes for GGT, cytokeratin 19 and OV-6. Oval cells also frequently form ductular-like structures or phenotypically show hepatocyte-like characteristics. After CS infection, the oval cells showed sequential morphological changes to atypical proliferating bile ductules and all hamsters thereafter developed well differentiated and anaplastic CCC at 16 week after CS infrection. In electron microscopy, some bile ductules were constructed by intermediate oval cells and bile ductular cells surrounded by thick basement membrane. The results of this study strongly suggest that CCC developed in the present study were originated from hepatic stem-like oval cells, supporting the theory of stem cell origin of cancers. In addition, this hamster model would be valuable for the molecular mechanistic study during chemical-triggered cholangiocarcinogenesis.

혈액희석이 가토 피판의 경피산소분압 및 생존에 미치는 영향

윤병일,민대홍 중앙대학교 의과대학 의과학연구소 1988 中央醫大誌 Vol.13 No.1

In dealing with many skin flap surgeries, the need of accurate and noninvasive method of measuring arterial oxygen tension is growing to assess the circulation of the flap. And the transcutaneous PO_2 is known to reflect well the arterial PO_2. Therefore, transcutaneous PO_2 monitoring equipment is now routinely used in neonatal intensive care units and is potentially available also to the plastic surgeons. Hemoudilution has been known as a good method to improve circulation and viability of skin flaps by some reporters. The purpose of this study is to investigate whether hemodilution improves circulation of skin flaps or not, by observing the changes of transcutaneous PO_2 and viability of skin flaps. Transcutaneous PO_2 of the normal skin and flaps were measured in 10 normal rabbits and 10 hemodiluted rabbits. The following results were obtained: 1. The mean transcutaneous PO_2 of the normal rabbit skin was 51.30±10.33 mmHg and 58.50±10.34 mmHg before and after hemodilution. 2. The mean transcutaneous PO_2 of the flaps in the control group at postoperative 1st, 3rd and 5th days was 22.50±3.79 mmHg, 23.50±4.22 mmHg and 26.10±4.15 mmHg respectively. And that in the hemodiluted group was 26.60±6.01 mmHg, 29.50±6.64 mmHg and 33.40±7.00 mmHg respectively. 3. In comparison to the preoperative normal skin of the same animal, the mean transcutaneous PO_2 of the flaps in the control group at postoperative 1st, 3rd and 5th days was 44.40±5.90%, 46.99±8.77% and 51.80±9.04% respectively, and 55.12±7.37% and 58.22±6.33% and 64.99±4.01% respectively in the hemodiluted group (% of normal). This means that the mean transcutaneous PO_2 of flaps in the hemodiluted group was about 11.7% higher than that of the control group. 4. The mean flap survival rate at postoperative 5th day was 44.30±4.40% in the control group and 54.90±6.12% in the hemodiluted group.

워터스, 파노라마 방사선사진과 Scanora 방사선사진의 상악동 점막비후 진단 결과의 비교

윤숙자,강병철,정현대 大韓口腔顎顔面 放射線學會 1995 Imaging Science in Dentistry Vol.25 No.2

The purpose of this study was to compare the diagnostic performance of Waters' and panoramic view ; maxillary sinus posteroanterior and lateral scanography of ?? for mucosal thickening of maxillary sinus as well as to identify the utility of ?? for the detection of maxillary sinus disease. The assessment was done at 66 maxillary sinuses in 45 patients and the results were as follows ; 1. Estimation of presence or absence of mucosal thickening. The sensitivity, specificity, and positive and negative predictive value of maxillary sinus posteroanterior and lateral scanography were 0.865, 0.860, 0.921, and 0.805 respectively and slightly higher than those of Waters' and panoramic views, which were 0.832, 0.835, 0.903, and 0.728 respectively. However, paired t-test showed no significant differences in the diagnostic performance of the two pairs of imaging modalities. 2. Estimation of the types of mucosal thickening. The diagnostic accuracy for type Ⅰ, Ⅱ, Ⅲ was 75.3% on Waters' and panoramic view ; 77.9% on maxillary sinus posteroanterior and lateral scanography. It was higher on the latter, but showed no significant differences from that on the former. 3. Reliability of interpretation. In intraobserver and interobserver agreement, both overall rates of agreement and kappa-value were slightly higher on maxillary sinus posteroanterior and lateral scanography than on Waters' and panoramic views. There was no significant differences between the two pairs of imaging modalities. These results suggested that scanogram is a useful diagnostic radiography as well as Waters' and panoramic views for detection of maxillary sinusitis.

鹽水溶液에서 스테인레스鋼의 孔蝕에 미치는 添加劑의 영향

崔丙鎭,金大龍,尹秉河 경북대학교 공과대학 1986 工大硏究誌 Vol.15 No.-

A statistic method was employed through galvano-static experiments in this study of pitting corrosion of SUS 430 stainless steel. When ethylen-diamine (NH_2-CH_2-CH_2-HN_2) as an inhibitor and ferric chloride(FeCl_3) as an aggressive agent are added to corrosive medium, those additives affect on the size, distribution and total number of pits formed. Which can be explained by means of potential barriers at the moment of pits' nucleation. And the largest pit, appeared as a peak in the pits' distribution curve, occupied the majority part of total pits' volume.

양자교환 방식에 의한 방향성 결합기의 제작 및 특성연구

소대화,채기병,강기성,윤형도 明知大學校 産業技術硏究所 1992 産業技術硏究所論文集 Vol.11 No.-

In this study, a directional coupler which is fabricated on X-cut LiNbO₃ substrate by using proton exchange method is described. It is found that the directional coupler waveguide varied widely with controlling diffusion process. On the other hand, the on-off state of modulator is performed by annealing process and self-aligned electrodes are used in fabricating the direction coupler. As a results, the direction coupler has good characteristics : the measured on-off switching voltage of about 2.7-3V.

말기신부전 환자에서 혈액투석 전후의 QT간격분산 비교

강대웅,정지용,윤나라,안치용,김종오,신병철,정종훈,김현리 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Background: Some cases of QT interval, corrected QT interval (QTc), QT dispersion (QTd) and corrected QT dispersion (QTcd) have been reported in ESRD, but these results are variable and the influence of a hemodialysis is still controversial, In this study, we investigated the effect of hemodialysis on QT and QTc interval and QT and QTc dispersion in patients with ESRD 15 min before and 15 minute after each hemodialysis. Methods: Sixty-seven patients with ESRD (men 33 & women 34) on three-times stable hemodialysis (>3 months) were randomly enrolled. Fifty control subjects with a similar age and normal renal function were enrolled from this hospital. Routine biochemical studies were measured pre- and post dialysis, at the time of the ECG. Plasma Na+, K+, BUN, creatinine, ionized calcium and phosphate were checked. Twelve-lead electrocardiographs were performed at 10㎜/mv and 50㎜/s using a HewIett-Packard Pagewriter 100, before and after a single hemodialysis session.The QT interval was measured from the onset of the QRS complex to the end of the T wave. If the end of the T wave was not clear in a particular lead then it was excluded from analysis. When U waves were present, the end of the T wave was taken as the nadir between the T and U waves. Each QT interval was corrected for heart rate using Bazett's formula (QTc==QT/√(RR)) (ms). The difference between maximal and minimal QT interval duration was defined as QT dispersion (QTd) in each of the 12 leads. Result: This study demonstrates that QT, QTd, QTcd is higher in hemodialysis patients compared with control subjects, and QT and QTd rise postdialysis to levels comparable to those seen acutely following myocardial infarction, when patients are at greatly increased risk of potentially fatal ventricular arrhythmias, Conclusions: QT interval and QT dispersion, markers of risk for arrhythmias and sudden death, are elevated in hemodialysis patients, and rise postdialysis. QT interval and QT dispersion is an easily obtainable, noninvasive, simple, inexpensive, and widely available method of risk stratification in uremic patients receiving chronic dialysis. Additional studies are needed to clarity whether increased postdialysis QT dispersion results in an increased occurrence of arrhythmias.

대장 및 직장암 환자에서 DNA Ploidy 및 증식능과 기존의 예후인자와의 상관관계 분석

김상철,김대성,노병선,윤광수 대한대장항문학회 1996 Annals of Coloproctolgy Vol.12 No.1

실험실적 당뇨성 흰쥐에서 acetaminophen의 대사에 관한 연구

임은주,윤병재,윤병재,조희숙,김대재,최종원 경성대학교 환경문제연구소 2000 環境硏報 Vol.10 No.1

Acetaminophen is one of the most important drugs used for the treatment of mild to moderate pain when an anti-inflammatory effect is not necessary. Phenacetin, a prodrug that is metabolized to acetaminophen, is more toxic than its active metabolite and has no rational indications. In this study, we were observed activities of free radical generating enzymes, free radical scavenging enzymes and glutathione-related enzymes as well as detoxification mechanism of against acetaminophen-induced hepatotoxicity in STZ-induced hyperglycemic rat. Activities of cytochrome p450, cytochrome b5, aminopyrine demethylase and aniline hydroxylase were changed by the treatment acetaminophen in hyperglycemic rats. It was also observed that activities of conjugating enzymes as sulfotransferase and UDP-glucuronyltransferase was slightly changes against acetaminophen-induced in hyperglycemic rats. Acetaminophen results in the significantly decrease in the level of hepatic glutathione concentration and √-glutamylcysteon, synthetase activities in hyperglycemic rats. And, glutathine S-transferase, superoxide dismutase and glutathione peroxidase activities were significantly increased against acetaminophen-inducedas in hyperglycemic rats. Glutathione reductase and catalase were not affected for experimental state. Furthemore, acetaminophen highered serum alanine, aspartate aminotransferase, sorbitol dehydrogenase, √-glutamylpeptidase, alkaline phosphatase and lactate dehydrogenase activities in hyperglycemic rats. Key Words: Hepatotoxicity, D/M, Acetaminophen, Glutathione, Glutathlone S-transferase, √-glutamylcystein synthetase