• 마이크로전자및패키징학회지
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• 제11권3호
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• pp.83-89
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• 2004

NTC 써미스터를 내장시킨 소형의 열전 냉각 모듈을 제작하고 LD와 같은 광통신부품에 적용하기 위한 온도제어 및 항온유지 특성을 분석하였다 BiTe계 열전반도체 21쌍으로 구성된 열전 모듈은 크기 $7.2 mm{\times}9 mm{\times}2.2 mm$이고, 내장된 써미스터의 빠른 응답속도로 인해 정밀온도제어가 가능하다. 열전 모듈은 성능 지수(Z) $2.5{\times}10^{-3}$/K, 300 K에서 최대 온도차(${\Delta}T_{max}$) 72 K, 최대 흡열량($Q_{max}$) 2.2W 값을 나타내었으며 온도 제어 정밀도는 대기 중에서 ${\pm}0.1^{\circ}C$내였다. 이는 광통신 부품의 작동 환경 안정성을 확보할 수 있는 항온제어용 소형 열전 모듈로서 적용이 가능하다.

• Journal of Pharmaceutical Investigation
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• 제39권3호
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• pp.221-226
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• 2009

The purpose of the present study was to evaluate the bioequivalence of two alprazolam tablets, Xanax 0.25 mg (Pharmacia Korea Pharm. Co., Ltd.) and Zyren 0.25 mg (Kwang Dong Pharm. Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The alprazolam release from two alprazolam tablets in vitro was tested using KP VIII Apparatus II method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solutions and water). The dissolution profiles of two alprazolam tablets were very similar at all dissolution media. Twenty four healthy male volunteers were divided into two groups with a randomized 2${\times}$2 cross-over study. After four tablets (1 mg alprazolam) were orally administrated, blood was taken and the concentrations of alprazolam in serum were determined using LC/MS/MS. The pharmacokinetic parameters such as $AUC_t$, $C_max$ and $T_max$were determined. Our results showed that the differences in $AUC_t$, $C_max$ and $T_max$ between two alprazolam tablets based on the Xanax were -11.65%, -4.44% and -39.31%, respectively. There were no sequence effects between two tablets in these parameter. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25)(e.g., log(0.8386)${\sim}$log(0.9453) and log(0.8596)${\sim}$log(1.1040) for $AUC_t$, $C_max$, respectively). Thus, Zyren 0.25 mg tablet was bioequivalent to Xanax 0.25 mg tablet.

• 한국임상약학회지
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• 제11권1호
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• pp.7-12
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• 2001

Cilostazol has both antithrombotic and cerebral vasodilating effects, and one of the mechanism is the selective inhibition of platalet cyclic AMP phosphodiesterase. Bioequivalence of two cilostazol tablets, the $Pletaal^{TM}$ (Korea Otsuka Pharmaceutical Co.) and the LG $Cilostazol^{TM}$ (LG Chemical Co.), was evaluated according to the guidelines of Korea Food and Drug Administration (KFDA). Sixteen normal male volunteers ($20\sim29$ years old) were randomly divided into two groups and a randomized $2\times2$ cross-over study was employed. After oral administration of $Pletaal^{TM}$ or LG $Cilostazol^{TM}$ tablet (100 mg cilostazol), blood samples were taken at predetermined time intervals and the serum cilostazol concentrations were determined using an HPLC method with UV/VIS detector. The pharmacokinetic parameters $(AUC_t,\;C_{max}\;and\;T_{max})$ were calculated and ANOVA was utilized for the statistical analysis. The results showed that the differences in AUCt, C_{max} and Tmax between two tablets based on the $Pletaal^{TM}$ tablet were $-5.39\%,\;2.32\%\;and\;4.26\%$, respectively. The powers (1-${\beta}$) for $AUC_t,\;C_{max}\;and\;T_{max}\;were\;83.81\%,\;96.02\%\;and\;91.04%$, respectively. Minimum detectable differences ($\Delta$) and $90\%$ confidence intervals were all less than $\pm20\%$. All these parameters met the criteria of KFDA for bioequivalence, indicating that LG $Cilostazol^{TM}$ tablet is bioequivalent to $Pletaal^{TM}$ tablet.

• Journal of Pharmaceutical Investigation
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• 제18권2호
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• pp.61-67
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• 1988

The influence of different suppository bases on the dissolution, and the bioavailability of aspirin suppositories in rabbits and humans was investigated using Witepsol H15 (WIT), WIT-Tween 80 (TWE), WIT-sodium lauryl sulfate (SLS), polyethylene glycol (PEG), hollow WIT (WIT-HOLL) and capsule incorporated into WIT (WIT-CAP). The results obtained were as follows: 1) Dissolution rates of aspirin suppositories with different bases in distilled water were faster in the order of WIT-TWE >WIT-SLS >PEG >WIT-HOLL >WIT >WIT-CAP. 2) The maximum blood levels $(C_{max})$ of aspirin in rabbits and humans were highest in WIT-TWE and WIT-SLS bases, but $C_{max}$ from WIT base was lower than that in oral administration of aspirin suspension. 3) The times reaching the maximum blood levels $(T_{max})$ in rabbits were 1 hr for oral administration, 1.5-2.5 hr for WIT-TWE, WIT-SLS, PEG, and WIT bases, and 2.5-4.0 hr for WIT-HOLL and WIT-CAP bases, but $T_{max}$ in humans were 1 hr for oral administration and WIT-TWE base, and 2-4 hr for WIT and WIT-HOLL bases. 4) Relative bioavailability (RBA) of aspirin suppositories in rabbits was higher in WIT-SLS, WIT-TWE and PEG bases than that in oral administration, and RBA of aspirin suppositories in humans was higher in the order of WIT-TWE >PEG >WIT-HOLL >oral >WIT bases tested. 5) Good correlation between dissolution rates and $C_{max}$ was obtained: y = 0.60x+32.23 (r = 0.96) for rabbits, and y = 0.60x+35.74 (r = 0.97) for humans.

• Journal of Pharmaceutical Investigation
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• 제34권1호
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• pp.43-48
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• 2004

The purpose of the present study was to evaluate the bioequivalence of two nizatidine capsules, Axid (Lilly Korea Pharm. Co., Ltd.) and Nex (Bi-nex Pharm. Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The nizatidine release from the two nizatidine capsules in vitro was tested using KP Apparatus method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solutions and water). The dissolution prefers of two nizatidine capsules were very similar at all dissolution media. Twenty four normal male volunteers were divided into two groups with a randomized 22 crossover study. After two capsules (300 mg nizatidine) were orally administrated, blood was taken and the concentrations of nizatidine in serum were determined using HPLC with UV detector. The pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were determined. The result showed that the differences in $AUC_t$, $C_{max}$ and $T_{max}$ between two nizatidine capsules based on the Axid were -6.16%, -8.26% and -1.82%, respectively. There were no sequence effects between two capsules in these parameter. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(125)(e.g., $log(0.91){\sim}log(0.97)$ and $log(0.85) {\sim}log(0.99)$ for $AUC_t$ and $C_{max}$ respectively), indicting that Nex capsule is bioequivalent to Axid capsule.

• Journal of Pharmaceutical Investigation
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• 제38권5호
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• pp.343-348
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• 2008

The bioequivalence of two cyclosporine A (CyA) 100 mg soft capsules (Chong Kun Dang's $Cipol-N^{(R)}$ as the test drug; Korea Novartis' Sandimmun $Neoral^{(R)}$ as the reference drug) was assessed in healthy male Korean volunteers after oral administration of 200 mg CyA according to a randomized crossover design. The whole blood samples were analyzed for the determination of parent CyA in the blood by using a validated HPLC/diode array detector method. The mean $AUC_t$ values for reference and test products were $4095.3{\pm}1397.2$ and $3958.3{\pm}1138.2\;ng{\cdot}hr/mL$, respectively. The mean $C_{max}$ values were $1135.9{\pm}293.2\;ng/mL$ for the reference product, and $985.0{\pm}207.9\;ng/mL$ for the test product. $T_{max}$ was $1.6{\pm}0.4\;hr$ for the reference and $1.8{\pm}0.5\;hr$ for the test product. The differences of $AUC_t$, $C_{max}$ and $T_{max}$ were -3.35, -13.28 and +10.63%, respectively. The point estimates and 90% confidence intervals for $AUC_t$ and $C_{max}$ were 0.981 (0.9171 to 1.0514) and 0.876 (0.8229 to 0.9336), respectively. Based on the pharmacokinetic and statistical data, we conclude that these two products are bioequivalent and can be considered interchangeable in the medical practice.

• The Journal of Advanced Prosthodontics
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• 제10권2호
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• pp.101-112
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• 2018

PURPOSE. The purpose of this study was to investigate the effect of various surface treatments (ST) on the shear bond strength of resin composite to three bilayer dental ceramics made by CAD/CAM and two veneering ceramics. MATERIALS AND METHODS. Three different bilayer dental ceramics and two different veneering ceramics were used (Group A: IPS e.max CAD+IPS e.max Ceram; Group B: IPS e.max ZirCAD+IPS e.max Ceram, Group C: Vita Suprinity+Vita VM11; Group D: IPS e.max Ceram; Group E: Vita VM11). All groups were divided into eight subgroups according to the ST. Then, all test specimens were repaired with a nano hybrid resin composite. Half of the test specimens were subjected to thermocycling procedure and the other half was stored in distilled water at $37^{\circ}C$. Shear bond strength tests for all test specimens were carried out with a universal testing machine. RESULTS. There were statistically significant differences among the tested surface treatments within the all tested fracture types (P<.005). HF etching showed higher bond strength values in Groups A, C, D, and E than the other tested ST. However, bonding durability of all the surface-treated groups were similar after thermocycling (P>.00125). CONCLUSION. This study revealed that HF etching for glass ceramics and sandblasting for zirconia ceramics were adequate for repair of all ceramic restorations. The effect of ceramic type exposed on the fracture area was not significant on the repair bond strength of resin composites to different ceramic types.

• Archives of Pharmacal Research
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• 제18권4호
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• pp.219-223
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• 1995

Rectal absorption of opeprazole, a proton pump inhibitor, from suppositories was studied in rabbits. The suppositories were prepared by the conventional melting method with two types of bases, water-soluble polyethylene glycol (PEG) 4000 and oil-soluble Witepsol H15 bases, and administered intractally (ir) to rabbits at a dose of 10 mg omeprazole/kg. The plasma omeprazole concentration-time profiles of the two suppositories were compared with those following intravenous 9iv) administration of the same dose. There were no significant differences between the two suppositories in bioabailabilities and peak plasma concentrations $(C_{max})$. Bioavaiabilities and $C_{max}$ of PEG- and Witpsol suppositories were 30.3 and 33.9%, and 7.0 and $5.6\mug/ml$, resepectively. However, PEG suppository showed significantly (p<0.05) shorter time to reach peak plasma concentration $(T_{max})$ mean absorption time (MAT) and mean residence time in the plasma (MRT) than Witepsol suppository. The $T_{max}$ MRT nad MAT were 25.0, 83.0 and 38.5 min for PEG syppository, but were 90.0, 122.5 and 78.0 min for Wiepsol supposiotory, respectively. These differences between thw two suppositories could be explanined by the difference in the in vitro dissolution rates between the suppositories. The dissolution of omeprazole form PEG suppository was reportedly much faster than that from Witepsol suppository. It suggests that plasma profiles of omeprazole, especially $C_{max}$ MAT and MRT, could be controlled by modifying the in vitro dissolution rate of the drug from the suppositories. Above results suggest that rectal suppository is worth developing as an alternative dosage form of omeprazole to the conventional oral preparations which need sophisticated treatments, such as enterix coating, to prevent acid degradation of the drug in the stomach fluid.

• 정보처리학회논문지C
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• 제16C권1호
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• pp.57-64
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• 2009

모바일 와이맥스에서 IP 기반의 무선 광대역 서비스를 효율적으로 제공하기 위해, 제한적인 무선링크의 대역폭을 보다 효율적으로 활용하는 방안이 필요하다. 모바일 와이맥스 표준에서 정의된 헤더 압축 기법인 PHS(Payload Header Suppression) 대신에 ROHC(RObust Header Compression) O(Bi-directional Optimistic) 모드를 사용할 경우, 압축효율성과 견고성 면에서 성능을 향상시킬 수 있으나[1, 2], 모바일 와이맥스의 음영서비스 지역이나 비트 에러로 인한 수신단에서의 연속적인 패킷의 손실이 발생할 경우 컴프레서와 디컴프레서가 유지하는 압축 정보가 비동기화되어 O 모드의 패킷 복구 실패율이 증가하게 되므로 이를 보완할 방안이 필요하다. 이에 본 논문에서는, 모바일 와이맥스 환경에서 패킷 손실에 대한 ROHC O 모드의 성능 향상을 위해 O 모드의 압축률과 견고성에 모두 영향을 미치는 Optimistic 파라미터의 값을 동적으로 조절하는 방안을 제안하고, OPNET 시뮬레이터를 사용하여 제안한 방안의 성능 분석을 하였다.

• 약학회지
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• 제39권6호
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• pp.636-644
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• 1995

Comparison of bioavailabflity (BA) of three brands of ranitidine (RT) tablets has been studied m rats. The purpose of this study was to characterize the pharniacolunetics of RT tablets in the rat and to coinpare phannacolunetic parameters of three brands of RT tablets. In addition, it was investigated whether plasma RT concentrations m humans can be predicted from pharmacokinetic parameters obtained in rats. RT was administered intravenously in dose of RT.HCI 10mg/kg and orally in dose of RT.HCI 50mg/kg as solution or crushed sample of thablets. Plasma RT concentrations were determned by HPLC. Plasma RT concentrations as a function of time were fitted to two compartment model. Plasma RT concentrations declined with a terminal half life ($t_{{1}/2{\betha}}$) of 40.9 min. The plasma RT concentration-time curve showed two peak plasma concentrations following an oral administration of solution or crushed sample in rats like humans. No significant difference among pharmacokinetic parameters was observed except $T_{max2}$ (p<0.05). The BA for crushed sample A, B and C were found to be 54.6 40.7 and 40.0%, respectively. Equivalence of $C_{max1}$ and $T_{max2}$ were guaranteed in this study. However, it was concluded that three brands of RT tablets are bioequivalent, taking the following characteristics of RT into consideration;(1) rapid onset of the effect is not required, (2) $C_{max1}$ and $T_{max2}$ do not seem to influence the effectiveness of the drug during a long-term treatment by the usual administration of twice a day. Results from this study were combined with plarmacokinetic data for RT in dogs and humans to develop a basis for interspecies scale-up of the disposition characteristics of the drug. there were similarities in the general disposition of the drug. Allometric relationships were sought between pharmacokinetic parameters nd species body weight. Significant interspecies correlations were found for total body clearance($Cl_{t}$) and steady state volume of distribution ($Bd_{ss}$). Thus, plasma RT concentrations in humans can be predicted from pharmacokinetic parameters obtained in rats.