• Archives of Pharmacal Research
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• 제19권1호
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• pp.30-35
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• 1996

Poly(l-lactic acid)(PLLA) microspheres loaded with ampicillin sodium (AMP-Na_, .betha.-lactam antibiotic, were prepared by a w/o/w multiple emulsion-solvent evaporation method. The amounts of each component in three phases (inner water phase, organic phase, and outer water phase) wre carefully examined in the preparation of PLLA microspheres. The stirring rate, another preparation parameter, was also investigated for study on the effect of mechanical stress on the drug loading and morphology of PLLA microspheres. Most of the preparation parameters had a great influence on the drug loading, surface morphology and size distribution of PLLA microspheres. PLLA microspheres with 15.89 w/w% drug loading were subjected to the in vitro release experimet. The release of ampicillin sodium was constant at a rate of 1.68 $mug/ml/day$ per 1 mg of microspheres for 18 days initial burst effect.

• 한국생산제조학회지
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• 제23권1호
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• pp.7-14
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• 2014

The core of the automotive industry's strategy to handle the climate change can be explained as the development and distribution of the vehicles with high fuel efficiencies and low emission. Clean Diesel, hydrogen fuel cell, electric, and especially hybrid power-train vehicles have been actively studied. This paper dynamically analyzes the performance of a hybrid system's five driving modes. The research subject consists of one engine, two electric motors, two simple planetary gears, and one compound planetary gears with five clutches. To define the steady state equation of the system, interaction formulas of five driving modes are introduced with motion variables and torque variables. These formulas are then used to analyze the speeds, torques, and power flows of each mode.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.628-630
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• 2004

Antitumor activities of a peptide fraction isolated from traditional Korean soy sauce (SSP) were investigated in vitro and in vivo using cancer cell lines and F9 teratocarcinoma-bearing BALB/c mice. SSP exerted a dose-dependent antiproliferative effect on P388D1 mouse lymphoma, F9 mouse teratocarcinoma, and DLD-l human colon cancer cells with $IC_{50}$ values of 11, 50, and $50\mug/ml$, respectively. Tumor growth in F9 teratocarcinoma-bearing BALB/c mice, orally administered with 80 and 200 mg/kg/day of SSPs, was inhibited 10.3% and 52.4%, respectively, and survival days increased by 11.9% and 22.1%, respectively, compared to the control group. The results of antitumor activities exerted by SSP in vitro and in vivo suggest the feasibility of using SSP as an antitumor agent.

• 한국대기환경학회지
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• 제3권2호
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• pp.11-17
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• 1987

Atmospheric particulate matter (A.P.M.) was collected on quartz fiber filters from March 1985 to February 1986 at Chung-Ang University according to particle size using Andersen high-volume air smapler, and benzo (a) pyrene concentration in these particulates were analyzed by high performance liquid chromatography. The annual arithmetic mean concentration of A.P.M. was 115.50$\mug/m^3$. The annual arithmetic mean concentrations of coarse particles and fine particles in A.P.M. were 52.54$\mum/m^3$ and 62.96$\mum/m^3$ respectively. THe annual arithmetic mean concentration of benzo(a)pyrene in A.P.M. was 1.44$ng/m^3$. THe annual arithmetic mean concentrations of benzo(a)pyrene in coarse particles and fine particles were 0.05 $ng/m^3$ and 1.39 $ng/m^3$ respectively. Thus, the concentration of benzo(a)pyrene showed maldistribution of 96.53% in fine particle. A.P.M. showed wide fluctuation according to the season. The concentration of A.P.M. was lowest in summer and high in spring and winter. Coarse and fine particle concentrations in A.P.M. were highest in spring and winter, respectively. The concentrations of benzo(a)pyrene was highest in winter and lowest in summer. The concentrations of benzo(a)pyrene in fine and coarse particles were highest in winter and spring, respectively.

• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.216-220
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• 2005

Periconicin A and B, two new fusicoccane diterpenes originally isolated from the cultures of endophytic fungus Periconia sp. OBW-15, were tested by several biological assays. Periconicin A was consistently more active than periconicin B. In an antifungal activity assay, periconicin A showed potent inhibitory activity against the agents of human mycoses, including Candida albicans, Trichophyton mentagrophytes, and T. rubrum, with minimum inhibitory concentration (MIC) in the range of 3.12- 6.25 $\mug$ /ml. In a plant growth regulatory activity assay, periconicins inhibited hypocotyl elongation and root growth of Brassica campestris L. and Raphanus sativus L. At concentrations below 1 μg/ml, however, both compounds accelerated root growth by 110- 135%. From these results, it is apparent that a methyl group positioned in a cyclopentane ring may play an important role in plant and fungal growth inhibitory activity.

• 한국동물학회지
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• 제20권2호
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• pp.93-99
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• 1977

HeLa $S_3$세포에서 MMC에 의해 유발된 DNA회복합성은 농도$(0.05\\sim 0.5\\mu g/ml)$에 따른 증가를 보이지 않고 그 율도 비\ulcorner적 낮아 $0.1\\sim 0.5\\mu g/ml$ 농도에서 조사한 전 세포의 $7\\sim 9%$를 나타내고 있다. 시간 변화에 따른 실험에서는 MMC를 제거한 후 24시간까지 거의 비슷한 율로 DNA회복합성이 계속되고 있다. thymidine 상사체중 BUdR을 전처리한 군에서만이 MMC에 의한 DNA회복합성을 증가시켰다. 그러나 BUdR 또는 IUdR과 MMC를 복합처리 할 경우 시간경과에 따라 정상 DNA합성은 감소된다. 이들 결과는 MMC에 의해 유발된 DNA손상은 빠르고 느린 두단계로 회복됨을 암시하는 것이라 생각된다.

• 한국임상약학회지
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• 제14권2호
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• pp.91-95
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• 2004

당뇨환자가 합병증으로 고혈압이 있을 경우 항고혈압약물인 딜티아젬을 투여시 딜티아젬의 동태학적 측면에서 투여계획을 설계하기 위해서 토끼에 알록산을 당뇨병모델을 만들었다. 알록산으로 유도된 급성 및 만성 당뇨 토끼에서 딜티아젬의 약물동태 변화에 대한 결과는 당므과 같다. 1. Alloxan 45 mg/kg을 토끼의 귀정맥에 투여시 혈당농도는 control군에서 $112\pm20.6\;mg/dl$, acute DM군에서는 $260\pm897\;mg/dl$, chronic DM군에서는 $331\pm85\;mg/dl$으로 당뇨가 유발되었음이 확인되었다.. 2. Alloxan에 의한 당뇨병 유발토끼에서 딜티아젬의 혈중농도곡선하면적(AUC)값은 대조군$(21.6\pm2.45\;\mug/ml)$ 보다 chronic DM군$(31.91\pm379\;mg/ml{\cdot}hr)$에서 유의성(p<0.05) 있게 증가하였다. 3. 딜티아젬의 요중누적배설량은 대조군에 비해 acute 및 chronic DM군에서 감소되었으나 유의성은 없었다. 4. 당뇨병 유발 토끼에서 딜티아젬의 토탈바디클리어런스$(CL_t)$ 값과 $\beta$-소실속도정수값이 대조군에 배해서 유의성(p<0.05)있게 감소되었다. 실험적 당뇨 토끼에서 딜티아젬의 생체이용률의 증가는 딜티아젬의 토탈바디클리어런스$(CL_t)$ 값과 베타의 소실속도정수 값이 대조군에 비해서 유의성있게 감소되었기 때문으로 사료된다.

• 한국대기환경학회지
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• 제5권2호
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• pp.21-29
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• 1989

The metals present in atmospheric particulate come from various sources; natural or anthropogenic. Among various metals Fe, Zn, Pb, Cu, and Mn are of particular concern in as much as they are not only present in large quantity, but toxic to human body. A simple, fast, and non-destructive analytical method for these metals in atmospheric particulate was developed and the analytical details were described herein. The method involves the measurements of X-ray fluorescence of sample contained in filters and comparing it with those for standards. The standard filters were prepared by applicating premeasured standard solution to the filters and then drying. The accuracy of the method was tested by analyzing standard reference materials and by independently analyzing samples using a different, previously accuracy-proven method, inductively coupled plasma atomic emission spectrometry, and comparing the results obtained. Analytical sensitivities and detection limits of the present method were 62.9, 178.2, 82.9, 146.1, 37.2, 120.3 cps/$\mug/cm^2$ and 39.0 35.6, 137.5, 125.9, 182.6, 72.8 $ng/cm^2$ for Fe, Zn, Pb, Cu, Mn, and Ni respectively. The method was applied to Seoul atmospheric particulate and some results were reported.

• 한국대기환경학회지
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• 제7권1호
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• pp.17-22
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• 1991

Total suspended particulates (TSP) in the atmosphere was collected and size-fractionated by Andersen high volume air sampler for one year (Mar. 1987 $\sim$ Feb. 1988) in Seoul. The concentrations of several polycyclic aromatic hydrocarbons and heavy metals were determined to investigate the atmospheric concentrations, seasonal variations and its relationship with the size distribution of suspended particulate matter. The arithmetic mean concentration of total suspended particulates was 200.44 $\mug/m^3$. The concentrations of heavy metals were 2433.80 for Fe, 629.49 for Zn, 600.71 for Pb, 143.87 for Cu, and 107.21 $ng/m^3$ for Mn, respectively. The concentrations of PAHs were 3.83 for benzo(a) pyrene, 2.95 for benzo(k)fluoranthene, and 4.42 $ng/m^3$ for benzo(ghi)perylene, respectively. PAHs, Pb and Zn abounded in particles below 2.0 $\mu$m, while Fe and Mn aboounded in particles above 2.0 $\mu$m. TSP and its chemical compositions showed the seasonal variations. The concentrations of anthrophogenic pollutants like TSP, PAHs and heavy metals in the fine particles were highest in winter and lowest in summer. PAHs and Pb analyzed showed significant correlations between each other and between TSP concentration in fine particles, indicating that the particles in which they are contained have a similar behavior in the atmosphere.

• Archives of Pharmacal Research
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• 제18권6호
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• pp.396-401
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• 1995

As a part of trials to develop the antitumor agent from tannins isolated from plants, the antitumor activity of peduculagin, an ellagitannin, isolated from Alnus hirsuta var. microphylla was examined in vitro and in vivo. In vitro, the cytotoxicity was determined by 0.4% typanblue dye exclusion method. peduculagin showed the dose-dependent cytotoxicity against human chronic myelogenous leukemia (K-562), human promyelocytic leukemia (HL-60), mouse lymphoid neoplasm (P388), mouse lymphocytic leukemia (L1210) and mouse sarcoma 180(S180) cell lines. $ED_{50}\; values\; (ED_{50})$ of each cell line were 5.30, 0.92, 2.78, 9.35 and $1.38 \mug/ml$ respectively. The most sensitive cell line was HL-60. In vivo, pedunculagin was administered to ICR mouse with the doses of 50 and $100{\;}{\mu}g/ml$intraperitoneally once at 20 days before S180 inoculation. peduculagin showed the antitumor activity and its T/C ratio (%) was 120.82% in the group of both concentrations.