• Biomolecules & Therapeutics
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• 제12권1호
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• pp.19-24
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• 2004

The vascular relaxant effect of amlodipine adipate, a new salt of amlodipine, was evaluate in isolated rat aorta, and compared with that of amlodipine besylate. Furthermore, antihypertensive effects were measured in hypertensive rat models, such as spontaneously hypertensive rats (SHR) and rena1 hypertensive rats (RHR). Amlodipine adipate concentration-dependently inhibited $Ca^{2+}$-induced contraction of rat aorta with a very slow onset of action (reached its maximum at 3.5 h;$IC_{50}$: 3.76 nM), having a pattern and a potency similar to those of amlodipine besylate ($IC_{50}$: 4.01 nM). In SHR and RHR, orally administered amlodipine adipate produced a dosedependent and long-lasting (>10-24 h) antihypertensive effect ($ED_{20}$: 2.48 and 1.57 mg/kg, respectively), with a pattern and a potency similar to those of amlodipine besylate ($ED_{20}$: 2.50 and 1.99 mg/kg in SHR and RHR, respectively). These results suggest that amlodipine adipate is a potent and long-lasting antihypertensive agent and that its antihypertensive effect is not significantly different to that of amlodipine besylate.

• 자원리싸이클링
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• 제30권5호
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• pp.32-37
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• 2021

본 연구는 모나자이트 침출액으로부터 용매추출을 통한 토륨의 추출 및 분리 가능성에 대해 연구하였다. 토륨 용매추출 공정을 위해 1차 아민계 추출제인 Primene-JM-T가 선택되었다. 토륨의 액-액 추출 공정을 위해 다양한 조건의 실험이 수행되고 조건이 확립되었다. 연구 결과로부터 추출제 검증, pH 조건, 추출제의 변화 및 추출 등온선의 작성 및 최종적으로 추출제로부터의 탈거 조건을 확립하였다.

• 약학회지
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• 제38권1호
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• pp.31-37
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• 1994

Active fraction, $P_2$, was Isolated from natural anti-cancer drug, $CP_2$, by HPLC. We confirmed that $P_2$ includes most of the Isoguanosine and minor components, Berberine and other protoberberine alkaloids, by $^1H-NMR$ and $^{13}C-NMR$ and measured tile cytotoxicity of $P_2$ against various tumor cell-lines.' $P_2$ was very effective to all tumor cell-lines, especially to human colon cancer SNU-C2A$(ED_{50};\;24{\mu}g)$ and liver cancer HEP-3B$(ED_{50};\;27{\mu}g)$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.399-402
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• 1988

In this paper, the relationship between stability and gain band-width product (GB) is clear ed by evaluating the feedback gain in the buck-boost switching regulator. Especially, considering the effect of the right-half-plane pole on the stability, we found available region of GB on the stability with the one pole compensation for the feedback circuit.

• Archives of Pharmacal Research
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• 제21권3호
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• pp.241-247
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• 1998

This study was designed to determine biochemical and pharmacological properties of a newly synthesized benzimidazole derivative, 2-amino-4, 5-dihydropyrido [1, 2-a] thiazolo [5, 4-g] benzimidazole (YJA20379-5) in vitro and in vivo. In the leaky membrane vesicles of pig gastric mucosa, YJA20379-5 inhibited the $K^+$-stimulated $H^+$, $K^+$-ATPase activity in a concentration- and time-dependent manner, with $IC_{50}$ values being $43{\mu}\textrm{M}$ and $43{\mu}\textrm{M}$ at pH 6.4 and 7.4, respectively. YJA20379-5, given intraduodenally, had a potent inhibitory effect on the gastric acid secretion in pylorus-ligated rats. The $ED_{50}$ value for acid secretion was 15.4 mg/kg. YJA20379-5, administered orally, also suppressed gastric damages induced by water-immersion stress, indomethacin and ethanol, and duodenal damage induced by mepirizole in rats; the $ED_{50}$ values were 17.6, 4.7, 3.0 and 18.7 mg/kg, respectively. Furthermore, repeated oral administration of YJA20379-5 accelerated the spontaneous healing of acetic acid-induced gastric ulcers in rats. It is concluded that the a-ntisecretory activity of YJA20379-5 appears to be associated with inhibition of $H^+$, $K^+$-ATPase, while its antigastric and antiduodenal lesion activities are primarily related to the antisecretory effect.

• 한국식품과학회지
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• 제38권2호
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• pp.202-208
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• 2006

제주지역에서 8, 9, 10월에 수상 적과하여 폐기되는 감귤 미숙(청)과를 자원화하기 위해 전기투석을 이용하여 착즙주스의 과도한 유기산을 제거하고, 이화학적 특성 및 기능적 특성에 대한 전기투석의 영향을 조사하였다. 착즙주스의 100분 전기투석 결과 총 산도는 3.15(8월), 1.62(9월), 1.45%(10월)에서 2.37(8월), 0.86(9월), 0.74%(10월)로 감소하였으며, $^{\circ}Brix$도 약간 감소하였으나 결과적으로 당산비는 각각 9.4%, 59.7%, 70.6% 증가하였다. 그러나 pH, 환원당 및 색도는 거의 변화가 없었다. 착즙액의 유리당은 거의 변화가 없었지만, 유기산 함량은 상당히 감소하였다. Flavonoids인 narirutin, hesperidin의 함량도 전기투석에 의해 약간 감소하였지만 유의적 차이는 없었다. 측정된 이온성분 중$K^+,\;PO_4\;^{2-},\;SO_4\;^{2-},\;Cl^-$의 함량은 전기투석에 의해 감소하였으며, 그 중에서도 $K^+$이 60% 이상으로 감소율이 가장 컸다. 그러나 $Na^+$함량만은 2.5-3.5배 증가하였다. 총 폴리페놀 및 전자공여 작용은 전기투석에 의해 각각 감소하였으나, 아질산염 소거효과는 거의 변화가 없었다. 미숙감귤착즙원액과 100분 전기투석한 미숙감귤착즙액을 가지고 색, 향, 맛,종합적기호도에 대해 관능검사를 실시한 결과 100분 전기투석한 미숙감귤착즙액이 종합적 기호도가 더 좋은 것 으로 조사되었고, 100분 전기투석한 미숙감귤착즙액을 가지고 $12^{\circ}Brix$로 가당을 한 후 기호성을 조사한 결과 산 함량이 적당한 9월 미숙감귤착즙액이 가장 좋은 것으로 조사되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권6호
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• pp.781-790
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• 2011

The effects of seedtime and maturity stage on nutritive value of five maize stover varieties, including conventional maize (Kexiangyu 11, CM), fodder maize (Huqing 1, FM), high oil maize (Gaoyou 115, HOM), sweet maize (Kexiangtianyu 1, SM) and waxy maize (Kexiangluoyu 1, WM), were examined based on chemical composition, in vitro gas production and in situ incubation techniques. Maize stover was sampled at d 17 and d 30 after tasseling, and designated as maturity stage 1 and stage 2, respectively. The average dry matter (DM) organic matter (OM), crude protein (CP) and fiber contents were the greatest for HOM, SM and FM, respectively. CM had the highest in vitro organic matter disappearance (IVOMD) and volatile fatty acid (VFA) concentration. The highest ammonia nitrogen ($NH_3$-N) concentration in the incubation solution, and effective degradability of DM ($ED_{DM}$) and neutral detergent fiber ($ED_{NDF}$) were observed in SM. Advanced maturity stage increased (p<0.05) DM content, $ED_{DM}$ and $ED_{NDF}$, but decreased (p<0.05) OM and CP contents, and decreased (p<0.05) b and a+b values, IVOMD and molar proportion of valerate in the incubation solution for maize stover. Maize sown in summer had greater (p<0.05) OM content, but lower DM, CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) content compared with maize sown in spring. Maize sown in summer had greater (p<0.001) IVOMD, $NH_3$-N concentration in the incubation solution and $ED_{NDF}$, but lower (p<0.01) ratio of acetate to propionate compared to maize sown in spring. The interaction effect of variety${\times}$seedtime was observed running through almost all chemical composition, in vitro gas production parameters and in situ DM and NDF degradability. The overall results suggested that SM had the highest nutrient quality, and also indicated the possibility of selecting maize variety and seedtime for the utilization of maize stover in ruminants.

• 폴리머
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• 제34권1호
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• pp.63-68
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• 2010

PLGA는 미국 식품의약품안전청(FDA)의 승인을 받은 합성고분자로서 생체재료로 널리 쓰이고 있다. 하지만, 분해산물인 산으로 인하여 염증반응을 일으키고, 독성물을 생산하여 세포증식률의 감소를 야기시킨다고 보고된바 있다. 이러한 PLGA의 단점을 보완하고자 생체재료인 피브린을 사용하였는데, 피브린은 피브리노겐의 풍부함과 이들의 정제가 비교적 용이하다는 장점을 가지고 있다. 본 연구에서는 PLGA의 염증완화에 대한 피브린의 효과를 알아보았다. 피브린 첨가에 따른 PLGA 다공성 지지체에 염증의 발현정도를 확인하기 위해 RT-PCR을 수행하였고 지지체와 조직 간의 상호작용을 통한 염증세포의 침윤과 대식세포 발생 정도를 확인하기 위해 H&E와 ED-1 염색을 수행하였다. 위 실험결과 천연재료인 피브린이 PLGA의 이물반응을 감소시키는데 긍정적인 영향을 미치는 것으로 확인되었다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.87-87
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• 1995

The muscarinic effects of carbachol were compared on the isolated ileums of guinea-pig, rat and rabbit to elucidate the underlying mechanism of species differences in sensitivity for carbachol. The ED$\_$50/ value estimated on the guinea-pig ileum was 4 to 6-fold lower than those obtained on the rat and rabbit ileums, but the K$\_$A/ values of carbachol determined by functional assays were almost identical with 12-l7 ${\mu}$M in all of three ileums. The competition data of carbachol for [$^3$H]QNB binding were best described by a two-site model yielding the Ki values of 0.4-0.6${\mu}$M and 12-16${\mu}$M for high(K$\_$H/) and low(K$\_$L/) affinity sites, respectively. The low affinity dissociation constants(K$\_$L/) of carbachol determined from receptor binding studies thus were not significantly different from the K$\_$A/ values estimated from functional studies. The percentage of receptor occupation that carbachol requires for half-maximal response was approximately 3 to 5-fold lower in guinea-pig compared to rat and rabbit whereas the density of muscarinic binding sites per gram of ileum measured by [$^3$H]QNB saturation isotherms was two-fold higher in guinea-pig than that in rat and rabbit. Therefore, the numbers of muscarinic receptors occupied at ED$\_$50/ values of carbachol were about two-fold lower in guinea-pig, suggesting two-fold greater intrinsic efficacy. These results indicate that the guinea-pig ileum has higher muscarinic receptor density and greater intrinsic efficacy for carbachol than the rat and rabbit ileums.

• 인터넷정보학회논문지
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• 제8권4호
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• pp.51-59
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• 2007

본 논문에서는 RFID 기술 중 리더와 태그간 900MHz 대역을 사용하여 교육용 시스템 설계를 제시하였다. 능동형 태그와 리더의 설계를 임베디드 환경에서 제시하였으며 리더와 접속 가능한 서버의 소프트웨어 개발은 PC 윈도우 운영체제 환경에서 실현하였다. 개발 환경으로는 AT89C51ED2가 리더와 태그의 프로세서로, 개발 언어는 C 언어로, 이를 제어하기 위하여 케일 C 컴파일러가 사용되었다. 서버인 PC에서는 비쥬얼 스튜디오상의 비주얼 C 언어가 사용되었다. 시스템의 기능 점검을 위하여 PC에서는 리더를 통해 태그 주소를 인지하고, 메모리에 데이터를 읽고 쓰는 기능을 첨가하여 900MHz 대역의 RFID 교육용 소프트웨어 시스템을 구성하였다.