• Journal of Power System Engineering
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• v.16 no.6
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• pp.19-23
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• 2012

DME HCCI기관의 단점은 디젤 엔진에 비해 기관부하 영역이 굉장히 좁다는 것이고 이는 저온산화반응이 너무 빨리 일어나서 노크를 발생시키기 때문이다. 저온산화반응을 억제하기 위해서 DME 연소에 미치는 천연가스의 영향을 실험한 결과, 천연가스가 DME의 저온산화반응을 억제시키기 때문에 기관부하영역이 확대된다는 것을 알았다. 본 연구에서는 서로 다른 세탄가를 가진 첨가연료가 DME 저온산화반응에 미치는 영향을 실험적으로 조사하였다. 그 결과 저온산화반응의 최고 열발생율은 세탄가에 의존하지 않지만 착화온도는 세탄가에 의존한다는 사실을 밝혔다.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.126-131
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• 1996

These experiments were conducted in the laboratory conditions to determine the prey consumption of a predaciousphytoseiid mite, Amblyseius womersleyi Schicha, and its ability to regulate the population of tea redspider mite, Tetranychus kanzawai Kishida. The functional response curve of the adult A. womersleyi to thedensity of eggs, larvae, and nymphs of T. kanzawai indicated Holling's Type 11: the consumption of prey bythe adult A. womersleyi increased with the prey density but the consumption rate decreased. The critical initialratio to suppress the prey population by the predator seemed to be 32:l @rey:predator) at 25"C, and 16:l at20$^{\circ}$C on kidney bean plant. The predator could not regulate any initial ratio of the prey population at 15$^{\circ}$C.^{\circ}$C.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.567-571
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• 1997

Numbers of chemical agents which have been shown to inhibit either auxin signal transduction pathway or ethylene formation in plant cells were applied to cut flower stems of snapdragon (Antirrhinum majus L.) and their effects on the postharvest gravitropic response were studied. The chemical treatments were done by submerging either the stem base or the top part of cut flower, which involves the gravistimulus-sensitive region, for 1 h at $25^{\circ}C$. When the chemicals were supplied from the cut stem base, the gravitropic upward bending of flower stalks kept horizontally after the treatments with 20 mM CDTA or 10 mM $CoCl_2$ was comparable to that of the untreated control, but o-vanadate showed a certain degree of effectiveness for suppressing the bending response. In contrast, the direct application of those agents to the gravitropically sensitive region of cut flowers in the presence of 0.01% Triton X-100 resulted in a substantial reduction of the gravitropic response. In the case of 20 mM $CoCl_2$ treatment, almost total elimination of gravitropism without any significant deterioration of flower quality was observed. The results indicate the possibility of preparation of a protocol involving $CoCl_2$ and a proper surfactant for commercial use to suppress the gravitropic response of cut flowers during postharvest storage and transportation.

• Science of Emotion and Sensibility
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• v.15 no.1
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• pp.37-46
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• 2012

We tested the effects of endogenous attention and reorienting on the performance of detection task. In the classic detection paradigm of Posner and Cohen (1980), performance on target detection is measured, where target appears either on the same or difference spatial location of cue stimulus after brief period of SOA (stimulus onset asynchrony). In this study, we induced exogenous attention by manipulating predictability of cue for target, and also induced reorientation by inserting additional (reorienting) cue between initial cue and target. Experiment 1 had three conditions of reorienting speed: Early, middle, and late. Facilitation and IOR (inhibition of return) occurred in different forms depending on SOA and reorienting speed, but we were not able to discover interpretable pattern in the results. However, reanalysis of early reorienting condition revealed that facilitation and IOR occurred in a crossed manner where short SOA found facilitation and long SOA did IOR, the typical results of simple detection task. Experiment 2 collected additional data to replicate the results in early reorienting condition of experiment 1. The results obtained that facilitation occurred with short SOA and IOR with long SOA. These results contrast with those of Wright and Richard (2000) where they reported elimination of IOR when cue had predictability of target locations. These results suggest that additional cue (here, orienting cue), which rapidly appears before extinction of IOR by prior cue, brings about double IOR. The present research demonstrates that even when attention is allocated to certain location via endogenous mechanism, rapidly repeating cues in certain location maximizes IOR that offsets the effects of endogenous attention to the same location.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1133-1138
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• 2000

본 실험에서는 동양에서 예로부터 민간요법이나 한방에서 주로 많이 쓰여지고 있는 8가지 종류의 한약재에 대해서 면역억제제로써 사용 가능성을 실험하였다. 그 결과, 당귀, 산사, 어성초, 오가피, 황기의 추출물은 동종항원에 반응하는 순수분리 T 세포의 증식을 농도 의존적으로 억제 시켰다. 또한 이들 T 세포의증식에 있어써 필수적인 IL-2를 포함한 cytokine 즉, IL-2, IL-4, IL-10, IFN-${\gamma}$ 의 생산량은 대조군에 비해 실험군에서 유의한 차이가 없었고 특히 T 세포 증식에 필수적인 IL-2의 생산량의 변화가 거의 없었다. 이는 한약재에 의한 T 세포증식에 필수적인 IL-2의 생산량을 억제하기 때문에 일어나는 결과가 아님을 알 수 있었다. 그리고 T 세포의 살세포작용 억제를 직접적으로 측정하기 위하여 세포내 LDH의 양을 조사한 결과 모든 대조군에서 50%이상의 살세포작용 억제가 일어났고, 그 중 특히 오가피와 황기에서는 100% 살세포작용 억제가 일어났다. 따라서 본 실험에서 사용되 당귀, 산사, 어성초, 오가피, 황기 등의 5가기 약재가 부작용 없는 면역억제로써 사용 가능성이 높은 것으로 생각된다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.289-289
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• 1994

흰쥐 적출 대동맥을 이용하여 혈관근의 $Na^{+}$/$Ca^{2+}$ 교환계의 기능과 성질을 구명코자 $Na^{+}$/$Ca^{2+}$ 교환계를 통한 수축 반응을 관찰하고 이때의 조직내 $Ca^{2+}$ 농도, cGMP 농도 및 이 수축에 대한 차단제와 저산소 처리의 영향을 조사하였다. 흰쥐 적출 대동맥은 $Na^{+}$ free 영양액하에서 수축반응을 일으켰고 이 수축 반응 ($Na^{+}$ free 수축반응)은 KCl 농도 증가에 비례하여 증가하였다. KCI 21.6mM 하의 $Na^{+}$ free유발 수축반응은 amiloride전처리하에서 용량-의존성으로 억제되었고 특히 tonic 수축반응이 예민하게 소실되었으며, benzamil과 verapamil 전처리하에서도 유의하게 억제되었다.

• Korean Journal of Microbiology
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• v.32 no.1
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• pp.84-90
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• 1994

Kinetic parameters of various substrates and inhibitors were measured to elucidate the binding requirements of the active site of intracellular adenosine deaminase (ADA) in Aspergillus oryzae. 3'-Deoxyadenosine was the best substrate according to the value of relative kcat/$K_m$. Purine riboside was found to be the strongest inhibitor with the $K_i$ value of $3.7{\times}10^{-5}$M. Adenine acted neither as a substrate nor as an inhibitor, suggesting the presence of ribose at N-9 of adenosine was crucial to binding. ADA also catalyzed the dechlorination of 6-chloropurine riboside, generating inosine and chloride ions. Substrate specificity of 6-chloropurine riboside was 0.86% of adenosine. Purine riboside, a competitive inhibitor of ADA, inhibit the dechlorination with similar $K_i$ value, suggesting that the same binding site was involved in deamination and dechlorination. Among the sulfhydryl group reagents, mercurials, pchloromercuribenzoate (PCMB), mersalyl acid and $HgCl_2$ inactivated the enzyme. Mersalyl acid-inactivated ADA was reactivated by thiol reagents, but PCMB-inactivated enzyme was not. When ADA was treated with the mercurial reagents, the inhibition constants and inhibition patterns were determined. Each inhibition was competitive with substrate. The $K_i$ values of these mercurial reagents were lower in 10 mM phosphate buffer than in 100 mM phosphate buffer, showing phosphate dependency.

• Journal of Dairy Science and Biotechnology
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• v.25 no.2
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• pp.1-4
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• 2007

The present study was performed to elucidate the ability of anti-$TNF-{\alpha}$ antibodies produced in sheep colostrums to neutralise $TNF-{\alpha}$ action in a cell-based bioassay and in a small animal model of intestinal inflammation. Colostrums from sheep immunized against $TNF-{\alpha}$ significantly inhibited $TNF-{\alpha}$ bioactivity in the cell based assay. The higher than anticipated variability in the two animal models precluded assessment of the ability of antibody to prevent $TNF-{\alpha}$ induced intestinal damage in the intact animal.

• The Journal of Internal Korean Medicine
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• v.26 no.1
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• pp.119-128
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• 2005

모든 알레르기 반응의 중심축이 되는 비만세포는 주로 피부, 위장관 및 호흡기관의 점막에 분포하고 있다. 활성화된 비만세포는 즉각형 알레르기 반응을 일으키는 여러 인자들을 방출시키게 된다. 方藥合編(방약합편)에 따르면 蔘蘇飮(삼소음)은 알레르기 鼻炎(비염), 發熱(발열), 風寒(풍한), 頭痛(두통), 기침에 效能(효능)이 있는 處方(처방)이다. 본 硏究(연구)는 蔘蘇飮(삼소음)의 肥滿細胞(비만세포) 의존성 아나필락시 반응(anaphylactic reaction)에 대한 藥理(약리) 效果(효과)를 조사하기 위한 것이다. 蔘蘇飮(삼소음)은 compound 48/80으로 유발되는 전신성 아나필락시 쇼크(systemic anaphylactic shock)와 耳介(이개) 浮腫(부종) 反應(반응)(ear swelling response)을 농도 의존적으로 억제하였다. 蔘蘇飮(삼소음)을 0.1, 1 mg/ml로 전처리 하였을 때, 흰쥐 복강 肥滿細胞(비만세포)(rat peritoneal mast cells, RPMCs)에서 compound 40/80에 의해 유발되는 히스타민 분비는 감소하는 것으로 나타났다. 또한 蔘蘇飮(삼소음)은 anti-dinitrophenyl IgE에 의해 활성화 된 수동 피부 아나필락시(passive cutaneous anaphylaxis, PCA)를 농도 의존적으로 抑制(억제)하였다. 결론적으로 蔘蘇飮(삼소음)은 肥滿細胞(비만세포) 의존성 즉각형 알레르기 反應(반응)을 抑制(억제)하여, 항 아나필락시 활성(anti-anaphylactic activity)을 가지는 것으로 보여 진다.

• Journal of Life Science
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• v.21 no.9
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• pp.1310-1314
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• 2011

Anti-inflammatory activities of septicine, a natural alkaloid product present in the leaves and stems of Tylophora ovata, were evaluated in lipopolysaccharide (LPS)-stimulated murine macrophages, RAW264.7 cells. Treatment with septicine inhibited LPS-induced nitric oxide (NO), inflammatory cytokines, tumor necrosis factor-${\alpha}$ and interleukin-6 production in a concentration-dependant manner. In addition, septicine suppressed the expression of inducible NO synthase. These results suggest that the anti-inflammatory activities of septicine might be attributed to the inhibition of NO, iNOS and cytokine expression.