• 월간산업보건
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• 통권51호
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• pp.24-27
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• 1992

• Archives of Pharmacal Research
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• 제17권5호
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• pp.364-370
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• 1994

A microscopic mass balance approach has been developed to estimate the extent and rate of absorption for camier-mediated comounds. For the case competitive inhibition in the presence of an inhibitor which shares the same camier, the fraction dose absorbed (F) and absorption rate constant ($K_a$) of a drug can be calculated from its concentration profile in the intestinal lumen. Absorption parameters obtained by single-pass perfusion experiments were used in the simultaion of the absorption of some aminopenicilins. Predicted fractions dose absorbed and absorption rate constants of ampicilin and amoxicilin were significantly reduced in the presence of a 6-times higher molar dose of cyclacilin. The drug-drug interactions on the competitive absroption of camier-mediated compounds were determined with regard to F and $K_a$. Predicted decreases in F for some aminopenicilins corrlated well with decrease in the urinary recovery in humans reported in the literature. Predicted decrease in the mean absorption rate constant ($\barK_a$) explain the delays in the time of peak plasma concentration ($T_{max}$) reported in humans.

• Archives of Pharmacal Research
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• 제17권2호
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• pp.57-59
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• 1994

The effect of sodium taurodihydrofusidate (STDHF) on drug permeation across nasal mucosa was studied in vitro using Ussing type diffusion chamber. Disodium cromoglicate (DSCG, M.W.5123) and fluorescein isothiocyanate-dextran (FD) of different molecular wieghts (M.W. 4400-71200) were used as model drugs. Pemeation profiles of DSCG and FDs showed a typical pseudo steady-state curve with short lag time. The pemeability coefficient of FD (M.W. 9400) sigmodially increased with increasing STDHF concentration. It also enhanced the DSCG pemeation. Interestingly the enhancement efficacy was independent of molecular weight of penetrants.

• 한국전기전자재료학회논문지
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• 제14권2호
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• pp.145-151
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• 2001

In this study, blue light emiting, soluble PPV copolymers were synthesized by Witting reaction and characterized. ITO/copolymer/Ca and ITO/copolymer/A1 structured light emitting diodes(LED) were fabricated and their I-V characteristics were examined. Copolymers showed $\pi$-$\pi$ transition in UV-Vis./NIR spectra. The PL and abosorption spectrum showed the symmetric vibration modes with mirror images which means that copolymers are highly aligned. By introducing aliphatic hydrocarbon group on polymer main chain, the solubility of copolymers was improved and no significant effects of substituent were observed. The band offset of copolymers are well suited as light emitting material for LED application than monomer or oligomer does. THe band offset of copolymers is ∼3eV in PL spectrum and the threshold voltages of ITO/copolymer/Ca and ITO/copolymer/Al structured LED 3V, 12V respectively. In the case of ITO/copolymer/Ca LED, it is believed that the amount of electrons and holes is well balanced and the recombination of opposite charges occurs easily because the work functions of Ca and Al electrodes are 2.9 and 4.3eV respectively and the difference in barrier height between polymer and electrode was small.

• 한국가스학회지
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• 제2권4호
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• pp.47-52
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• 1998

수냉식 흡수식 냉동기에 주로 사용되고 있는 LiBr/water 흡수용액을 대체할 수 있는 신흡수 용액으로 제안된 흡수용액중 4성분계 흡수용액($LiBr+LiNO_3+LiC1+H_2O$)의 수증기 흡수성능을 수직관 흡수기를 사용하여 시험하였다. 시험변수로는 입구농도, 입구온도, 냉각수 입구온도, 용액유량을 변경하였다. 수증기 흡수특성 시험 결과 4성분계 용액이 LiBr/water용액보다 $2\%$ 높은 농도에서 대둥한 흡수력을 가짐을 알 수 있었다. 그러나 4성분계 흡수용액이 LiBr/water용액보다 $3\%$정도 용해도가 높으므로 실제 흡수식 냉동기에 적용시 LiBr용액보다 우수한 흡수능력을 가질 수 있어 소형, 공냉형 흡수식 냉동기에 적용이 가능하다.

• Preventive Nutrition and Food Science
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• 제3권1호
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• pp.1-9
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• 1998

Studies were performed to 1) investigate if ferric iron bound in complex with iron-solubilizing meat components is absorbable, 2) compare the relative iron-solubilizing capaicty of meats, and 3) investigate the physicochemical and compositional characteristics if meat meat has iron-solubilizing components . Iron-solubilizing components of beef were isolate from pH 2 HCL homogenates into dialysis bags(MWCO of 6-8K). Radiolabelled iron complexes were then generated using ferric iron and the isolated low-molecular-weight components(ILC) from undigested beef or ascrobate. The bioavailabilities of radioiron in these complexes or as ferric iron were measured as radioiron absorption into the blood one hour after injection into ligated duodenal lops of rats. Iron absorptions were ferrous -ascorbate complexes(18.8$\pm$2.2%)> ferric-ILC complexes(4.9$\pm$0.6%)>ferric iron (23.2$\pm$0.3%)(p<0.05). ILC from 0.1g of beef, pork, chicken, fish , or egg white were added to 400$\mu$g ferric iron in pH 2 HCL, the pH raised to 7,2, and soluble iron determined in the supernatant after centrifugation at 2,500g for 10 min. Iron solubilizing capabilities of ILC were pork (99.9$\pm$0.1%)>beef(93.6$\pm$3.5%)> chicken (75.8$\pm$1.8%) > fish(64.6%$\pm$3.6%)>egg white(50.9$\pm$0.9%)(p<0.05). The compositional and physico-chemical characteristics of the ILC from the above dietary protein sources were investigated.

• 대한수의학회지
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• 제35권3호
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• pp.471-480
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• 1995

The purpose of this experiment was to develop a simple and reliable HPLC method for the detection of ciprofloxacin in chicken serum and to provide a basic data on pharmacokinetic parameters after oral and intramuscular administration. The results obtained were as follows: 1. 0.2% meta-phosphoric acid: acetonitrile(7:3, v/v) solution had a high and regular recovery rates and was selected as an extraction solution. 2. The recovery rates of ciprofloxacin were 83-97% with the selected solution in chicken serum and the detection limit was 50ng/ml in serum. 3. Ka(abosorption rate constant) were 3.652 1/h in fasted group and 0.880 1/h in non-fasted group, and Ke (elimination rate constant) were 0.061 1/h and 0.133 1/h, respectively. 4. The highest concentration in serum after intramuscular injection was 840ng/ml within 15-30min and 160-324ng/ml in 1.1-3.2 hours after oral administration. 5. The time course of blood concentration fits well into a 2 compartment model. 6. On oral administration of ciprofloxacin with feed, ciprofloxacin was absorbed more slowly and the amount of absorbed was smaller than that of in fasted chickens. 7. Blood concentration of ciprofloxacin increased in a dose-dependent manner after intramusclular and oral administraiton.

• 한국잡초학회지
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• 제7권2호
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• pp.208-219
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• 1987

최근(最近)에 수도용(水稻用) 제초제(除草劑)로 개발(開發)된 수종(數種)의 신제초제(新除草劑)들의 못자리 및 본답(本畓)의 잡초방제효과(雜草防除效果)와 이들의 작용성(作用性)을 구명(究明)하기 위해 1986년(年) 영남작물시험장(嶺南作物試驗場)에서 일련(一連)의 실험(實驗)을 실시(實施)하였던 결과(結果)는 다음과 같다. 1. 최근(最近) 개발(開發)된 수도용(水稻用) 제초제(除草劑) 중(中)에서 상면진압(床面鎭壓)못자리에서도 벼에 대(對)한 약해(藥害)가 거의 없으면서 제초효과(除草效果)가 우수(優秀)하였던 제초제(除草劑)는 pyrazolate 또는 pyrazoxyfen의 파종전(播種前) 처리(處理)와 quinclorac의 파종후(播種後)10일(日) 처리(盧理)하였다. 2. 이앙답(移秧畓)에서 일년생( 一年生) 및 다년생(多年生) 잡초(雜草)에 대(對)한 살초효과(殺草效果)가 높으면서 벼에 대(對)한 약해(藥害)가 겨의 없었던 처리(處理)는 NC-311와 butachlor 또는 quinclorac와의 혼합처리(混合處理)였는데 이들 혼합처리(混合處理)는 피의 엽기(葉期)가 2.5 엽기(葉期)까지도 90% 이상(以上)의 살초효과(殺草效果)를 보였으며 NC-311 + quinclorac의 혼합방법(混合方法)이 NC-311 + butachlor의 혼합방법(混合方法)보다 높은 살초력(殺草力)을 유지(維持)하였고 살초력(殺草力)을 유대(維待)하였고 살초력(殺草力) 지속기간(持續期間)도 길었다. 3. pyrazolate와 sulfonyl urea계(系) 제초제(除草劑)인 DPX-5384, CGA 142464, NC-311은 벼에 대(對)한 안전성(安全性)이 대단(大端)히 높았는데 지상부(地上部) 생육(生育)보다는 지하부(地下部) 생육억제영향(生育抑制影響)이 높은 경향(傾向)이었고, 이들 제초제(除草劑)에 대(對)한 품종간(品種間) 반응(反應)에 있어서도 일본형(日本型) 품종(品種)인 낙동(洛東)벼가 통일형(統一型) 품종(品種)보다 민감(敏感)한 반응(反應)을 보였다. 4. 이들 제초제(除草劑)의 흡수부위(吸收部位) 영향에 있어서는 벼의 경우 흡수부위(吸收部位)에 관계(關係)없이 大端(대단)히 안전(安全)하지만 피에 대(對)해서는 sulfonyl urea계(系)의 경우는 유아부(幼芽部) 흡수(吸收)가, pyrazolate와 Quinclorac의 경우는 유근부(幼根部) 흡수(吸收)가 주흡수(主吸收) 경로(經路)가 되었으며 피에 대(對)한 살초효과(殺草效果)는 Quinclorac이가장 탁월(卓越)하였다.