• 한국의학물리학회지:의학물리
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• 제10권3호
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• pp.125-131
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• 1999

현재 임상적으로 쓰이고 있는 T$_1$/T$_2$ 강조영상 (weighted image) 은 각각 다른 조직이나 정상/병변 조직 사이에 정성적인 대조도를 준다. T$_1$/T$_2$ 영상화 (mapping)는 영상의 각 화소신호랄 T$_1$/T$_2$ 시간으로 나타내는 방법으로 병변의 진행정도를 정량적으로 알 수 있다. T$_1$/T$_2$ 영상화 (mapping)를 얻기 위해서는 수신신호의 증폭률이 같아야 하는데, 일반적으로 MR 영상화 장비에서는 A/D converter 의 동적 구간을 최대 활용하기 위하여 입력신호를 최대 증폭하기 때문에 각각 다른 수신 증폭률을 사용할 수 있다. 이 논문에서는 최대 증폭한 경우와 수신증폭률을 보정한 경우의 T$_1$/T$_2$ 영상을 각각 얻고 측정된 T$_1$/T$_2$ 값을 비교하여 수신증폭률 보정이 T$_1$/T$_2$ 영상화에 어떠한 영향을 미치는지 분석하였다. 그 방법으로서 얻은 영상들이 각각 다른 수신증폭률을 가진 경우에 이를 보정하기 위해 잡음을 표준편차로 이용하는 방법을 사용하였다. 이렇게 얻어진 머리의 T$_1$/T$_2$ 영상은 이미 보고된 T$_1$/T$_2$ 의 값과 유사하였다.

• 대한한의학방제학회지
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• 제16권2호
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• pp.133-144
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• 2008

Recently, people are becoming fatter in most parts of the world. Obesity is regarded as an important risk factor to adversely affect the health of humans, associated with hypertension, hyperlipidemia, diabetes, and cardiovascular diseases. In the present study, therefore, we tested the short time efficiency and safety of Bangpoongtongsungsan as a drug to decrease body weight in subjects with obesity. A total 48 volunteers (24 man, 24 woman) with body mass index (BMI : weight in kg divided by square of height in meters) of $23㎏/m^2$ participated in clinical study for 12 weeks, from 2008, March 01 to 2008, Jun 30. The subjects was received a dietary supplement of 12 pieces hard capsules per day (4 pieces in one, 3 times in a day) during the clinical study. At the end of clinical study, body weight of subjects was significantly decreased from $72.21{\pm}11.44\;kg$ to $70.53{\pm}11.67\;kg$ (p<0.05). Waist circumferences of subjects were reduced $91.58{\pm}6.43\;cm$ to $85.25{\pm}7.70\;cm$ (p<0.05). Also, a BMI of subjects was significantly decreased $26.07{\pm}2.35\;kg/m^2$ to $25.63{\pm}2.63\;kg/m^2$ (p<0.05). Particularly, a decrease in body weight, waist circumferences, and BMI was more significant in woman than man. But, other biochemical levels including lipid and glucose in plasma had no changes at the end of clinical study. In conclusion, administration of Bangpoongtongsungsan in subjects with high body weight fat could inhibit obesity associated with a decrease in body weight, waist circumferences, and BMI.

• Journal of Periodontal and Implant Science
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• 제32권3호
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• pp.665-683
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• 2002

A novel glucanhydrolase from a mutant of Lipomyces starkeyi KSM 22 has additional amylase activity besides mutanolytic activity and has been suggested as promising anti-plaque agent. It has been shown effective in hydrolysis of mutan, reduction of mutan formation by Streptococcus mutans and removal pre-formed sucrose-dependent adherent microbial film and has been strongly bound to hydroxyapatitie. These in vitro properties of Lipomyces starkeyi KSM 22 glucanhydrolase are desirable for its application as a dental plaque control agent. In human experimental gingivitis　model and 6 month clinical trial, mouthrinsing with Lipomyces　starkeyi KSM 22 dextranase was comparable to 0.12% chlorhexidine mouthwash in inhibition of plaque accumulation and gingival inflammation and local side effect was negligible. This study was aimed to evaluate the cytotoxic effect of Lipomyces starkeyi KSM 22 glucanhydrolase on human gingival fibroblasts. Primary culture of human gingival fibroblasts at the 4th to 6th passages were used. Glucanhydrolase solution was made from lyophilized glucanhydrolase powder from a mutant of Lipomyces stakeyi KSM 22 solved in PBS and added to DMEM medium to the final concentration of 0.5, 1, and 2 unit. Cells were exposed to glucanhydrolase solution or 0.1 % chlorhexidine and the cells cultured in DMEM with 10% FBS and 1% antibiotics as control. After exposure, the morphological change, cell attachment, and cell activity by MTT assay were evaluated in 0.5, 1.5, 3, 6, 24 hours after treatment. The cell proliferation and cell activity was also evaluated at 2 and 7 days after 1 minute exposure, twice a day. The cell morphology was similar between the Lipomyces smkeyi KSM 22 glucanhydrolase groups and control group during the incubation periods, while most fibroblasts remained as round cell regardless of incubation time in the chlorhexidine group. The numbers of the attached cells in the glucanhydrolase groups were comparable to that of control and significantly higher than the chlorhexidine group. The numbers of the proliferated cells in the glucanhydrolase groups at 7 days of incubation were comparable to the control group and higher than the chlorhexidine group. The cell activity in glucanhydrolase groups paralleled with the increased cell number by attachment and proliferation. According to these results, Lipomyces starkeyj KSM 22 glucanhydrolase has little harmful effect on attachment and proliferation of human gingival fibroblasts, in contrast to 0.1% chlorhexidine which was cytotoxic to human gingival fibroblasts. Therefore this glucanhydrolase preparation is considered as a safe and promising agent for new mouthwash formula in the near future.

• Toxicological Research
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• 제22권4호
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• pp.381-390
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• 2006

Astaxanthine is a pigment that belongs to the family of the xanthophylls, the oxygenated derivatives of carotenoids whose synthesis in plants derives from lycopene. Astaxanthine is also a carotenoid widely used in salmonid and crustacean aquaculture to provide the pink color characteristic of that. Recent study reported that astaxanthine has the role as a detoxicant against the free radicals. On our study, we estimated the genotoxicity in ICR mice and possibility as antioxidant reagents of mutant Phaffia rhodozyma strain over expressing the astaxanthine by gamma-lay and carophyll pink including astaxanthine in apoE knock out mice, respectively. In our study, we administered Phaffia rhodozyma (2 mg and 3 mg) and carophyll pink for 4 and 8 week. The clinical sign and mortality were not detected compared with control groups. In the mutant frequency of hprt gene and chromosome aberration in splenic cells, there was not detected abnormality. There was not critical change in hematological and serum biochemical test compared to control. In expression level of repair enzyme, increase of catalase were detected and increase of expression level of Nrf-2 was detected in Phaffia rhodozyma (3 mg) and carophyll pink in 8 week treated group. In GSH level, the group of treated with Phaffia rhodozyma (3 mg) showed the increase of the GSH. In conclusion, mutant Phaffia rhodozyma and caphyll pink may be applied to the effective food additives to reduce the free radical.

• 한국동물위생학회지
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• 제29권1호
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• pp.55-63
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• 2006

Alcoholism and alcohol abuse are major public health concerns. This is linked to the injury of many organs, especially liver. Experiments were peformed to know the acute effects of LeeKwaDoo (LKD) induced by two-third partial hepatectomy (PH) in rats. In liver samples, regeneration parameters and histological assessment were performed. For the blood biochemical study, the blood were assayed with AST, ALT. The portal branch of liver lobes was ligated in the male Sprague-Dowley rats, two-thirds partial hepatectomies were also performed. It was estimated bodyweight and relative liver weight for the index of liver mass. For the marker of blood chemistry, we investigate the serum sample of rats and demonstrated the level of AST, ALT. Remaining tissues of liver developed as microscopic structures. Resection of the lobes in PH+LKD group resulted in a marked change of liver weight, blood chemistry and histological changes. The initiation of the proliferative response in PH group stimulated as well as reduction of the liver mass. On the other hands, the Initiation of the proliferative response in PH+LKD group delayed. Eventually, both PH group and PH+LKD group was restored relative liver weigh after 7 day. In conclusion, the acute adminstration of LKD seems to inhibit the initial response of liver regeneration through alcohol effects.

• 공업화학
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• 제25권2호
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• pp.134-141
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• 2014

환경오염, 기후변화, 고갈되어가는 화석원료에 대한 문제를 해결하기 위해 재생가능한 자원으로부터 케미칼 및 고분자 등의 산업자원을 생산하는 친환경 공정개발에 많은 연구가 진행되고 있다. 최근에 재생가능한 바이오매스로부터 다양한 케미칼 및 고분자 등을 생산하는 바이오리파이너리 공정이 많은 관심을 받고 있으며, 석유화학기반산업을 보완 혹은 대체할 가능성이 매우 높은 친환경공정으로 생각되고 있다. 본 총설에서는 바이오리파이너리 공정에 핵심적인 촉매로 사용되고 있는 재조합 미생물의 개발의 최근 동향을 바이오나일론, 바이오폴리에스터의 생산을 위하여 개발되고 있는 재조합 미생물의 대사공학전략을 중심으로 살펴보고자 한다.

• 한국농림기상학회지
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• 제15권4호
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• pp.282-290
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• 2013

대기와 지표면을 구성하고 있는 토양 및 식생은 생물리학적/생지화학적인 과정을 통해 서로 상호작용을 한다. 이러한 과정을 모의하기 위해 지표모델과 작물 생육모델이 사용되고 있다. 지표모델인 Noah MP 모델과 작물생육모델인 CERES-Rice 모델을 비교하기 위해 해남 플럭스 관측소 인근 지역에서 작물의 생육과 증발산량을 모의하였다. 플럭스 관측자료가 수집된 2003년부터 2012년까지 해남 플럭스 관측소의 주요 식생인 벼를 대상으로 생육과 증발산량을 모의되었다. Noah MP 모델은 단순한 식생 모의 과정으로 인해 개화기를 전후로 하는 벼의 LAI 변화양상을 정확하게 반영하지 못하였다. 벼의 생체중 예측에 있어서도 실제 관측될 수 있는 생체중보다 대략 10분의 1 수준에 해당하는 생체중이 모의되었다. 증발산량 모의의 경우에도, CERES-Rice 모델의 모의값보다 약 21%에 해당하는 증발산량을 모의하였다. 반면, CERES-Rice 모델의 경우 LAI의 변화와 생체중 모의 값은 실제의 벼 생육 양상과 유사할 것으로 추정되었다. 또한, 증발산량의 경우에도 해남 플럭스 관측소에서 측정된 값과 비교하였을 때 Noah-MP모델의 모의값이 CERES-Rice 모델의 모의값에 비해 RMSE 값이 1.8배 높았다. Noah MP 모델이 보이는 높은 오차값들은 Noah MP모델이 논의 지표상태를 적절히 반영하지 못하였기 때문으로 사료되었고, 특히 과소추정된 생체중을 보정하여 증발산량을 예측할 경우 오차를 30%까지 줄일 수 있을 것으로 보인다. 따라서, Noah MP 모델에 논에서의 지표 특성을 반영할 수 있다면 보다 정확한 물질순환과 에너지 교환을 예측할 수 있을 것으로 사료된다.

• Toxicological Research
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• 제20권4호
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• pp.365-374
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• 2004

Inhalation toxicity, mutagenicity, and immunotoxicity tests were performed using a smoke generation system to investigate the safety of Herbrette, a tobacco substitute made with the leaves of Perilla frutescens. ICR mice were exposed to nicotine-free Herbrette smoke with concentrations of 0 (control), 4.08 $\pm$ 1.32 mg/$m^3$ (low dose), 7.72 $\pm$ 2.14 mg/$m^3$ (medium dose) and 12.83 $\pm$ 1.69 mg/$m^3$ (high dose) total particulate matters (TPM) for 4 weeks. When compared to the control group, the body weights, organ weights in the exposed groups did not show any significant differences. However, certain change of several serum chemical data and biochemical parameters were observed, however, the changes were within normal physiological ranges. Moreover, no changes in organ weight, and no gross/microscopic changes were observed between the exposed and control groups. Salmonella typhimurium reverse mutation, in vivo chromosomal aberration and micronucleus assays revealed that Herbrette did not induce mutagenicity. Upon evaluation of peripheral cellular immunity of mice through in vitro lymphocyte proliferation assay, no significant difference was observed in mean stimulation index between the exposed and control groups. Taken together, our results strongly suggest that Herbrette may not cause toxicity on mice under current condition.

• Toxicological Research
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• 제8권2호
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• pp.217-233
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• 1992

This study was performed to determine the toxic effects of graded dose levels of SKI 2053R after repeated administration. Three groups of Sprague-Dawley rats(10M and 10F per group) were given a total of 25 i.v. injections of SKI 2053R (1.50,3.75,9.38mg/kg/day). In order to compare the toxic effects of SKI 2053R with those of cisplatin, one group of Sprague-Dawley rats (10M and 10F per group) were given a total of 25 i.v.injections of cisplatin (1.70mg/kg/day). The dosing schedule was divided into five courses of 5 consecutive days with 16-day dose-free intervals between each course. No drug-related toxicity occurred in low dose level group (1.50mg/kg/day) of SKI2053R. From the results of hematological examination, peripheral WBC counts, RBC counts and hemoglobin of high dose level group(9.38mg/kg/day)of SKI 2053R were significantly lower than those of no-treated group. Other toxicities including reduced final body weight, proteinuria and hematuria were observed in high dose level group of SKI 2053R. But, no change was detected in serum biochemical values of SKI 2053R treated groups. All of the rats in cisplatin treated group were died between 3 and 13 weeks, while rats treated with SKI2053R survived to the end except one rat of middle dose level group(3.75mg/kg/day). In histopathological examinations, rats that received cisplatin manifested severe tubular damage in kidney and hemosiderosis in spleen, but no critical pathological lesion was observed in rats of other groups. Considering the results of this study, it was concluded that non-toxic dose of SKI 2053R in this treatment schedule was estimated to be 3.75 mg/kg/day and the maximum tolerated dose was to be higher than 9.38mg/kg/day. The toxic profiles fo SKI 2053R were different from those of cisplatin, and its toxicity was considerably lower than that of cisplatin.

• 대한수의학회지
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• 제45권4호
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• pp.527-536
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• 2005

The effects of dietary Gleditschia on fatty acid composition, lipid oxidation, and pork quality were investigated. Pigs (n=40) were fed a diet containing 0, 0.1, 0.2, 0.4, and 1% Gleditschia for 14 weeks and slaughtered at 110 kg average. The longissimus throracis et lumborum muscle was collected at 24 hr postmortem. Pork loin chops (3 cm thick) were packaged aerobically and stored at $4^{\circ}C$ for 7 days. Samples were analyzed for fatty acid composition, ultimate pH, thiobarbituric acid-reactive substance (TBARS), color ($L^*$, $a^*$, $b^*$), drip loss and water-holding capacity. There was no significant difference of moisture and crude fat percent in between treatment and control group, and the color stability of pork loin better in all treat groups was more improved during cold storage. The change of pH was significantly increased (p<0.05) in 0.2, 0.4, 1% treatment groups compare to the control group. Water-holding capacity of pig loins was significantly higher (p<0.05) in all treat groups than in control group; 0.2% treat group was the highest in the water holding capacity followed by 0.4, 1, and 0.1% treat groups. Less drip loss of pig loin was observed with samples from Gleditschia-fed pigs except 1% treat group. Unsaturated fatty acid were tend to be decreased and saturated fatty acid were tend to be increased in Gleditschia-treated group. Thiobarbituric acid-reactive substance value of control was significantly higher than that of the Gleditschia-fed group (p<0.05).