• Journal of Ginseng Research
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• 제19권1호
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• pp.22-26
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• 1995

The present study was undertaken to elucidate the characteristics of red ginseng total saponin in behavioral changes on ambulation, forced swim test and convulsion in mice. The ambulation and the duration of immobility on forced swim test were not affected by red ginseng total saponin. On the other hand, the duration of immobility inducted by DMI, PGL but not CIP was significantly decreased, and the onset of convulsion induced by pentylenetetrazole was significantly shortened by preadministration of red ginseng total saponin. These results suggest that red ginseng total saponin component may play an important role in modulating synergism with drugs acting on depression and convulsion, and that the characteristics of synergetic effect induced by red ginseng total saponin potentate the central norepinephrine neuron activity.

• The Korean Journal of Ecology
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• 제20권2호
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• pp.95-102
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• 1997

Ring width chronologies of blue pine (pinus wallichiana) from two mesic sites, Kanasar(2, 400 m) and Gangotri(3, 000 m), in the western Himalayan region. India were developed to understand tree growth-climate relationship and its applicability in proxy climate studies. The resoponse function analyses of the two chronologies show that the site conditions play an important role in modulating the effect of climatic variables on tree growth. Winter temperature, prior to the growth year, has been found to play positive influence on blue pine growth at both sites. Summer temperature also has very similar response except for June and August. June temperature has negative influence at the lower in contrary to at the higher site. Low August temperature favors tree growth to precipitation has been found to vary which could be due to different precipitation regime at the two sites. Winter precipitation is important for tree growth at the higher, whereas summer at the lower sits. The present study suggests that the tree ring materials of blue pine from the temperate Himalayan regions could be used to develop chronologies for the reconstruction of seasonal climatic variables.

• 한국광학회지
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• 제3권3호
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• pp.155-160
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• 1992

평행한 단색광이 회절격자에 입사하면 회절격자의 뒷쪽 공간의 특정한 위치마다 반복하여 격자선 무늬를 본뜬 그림자가 생기는 지점이 나타난다. 빛의 회절로 인하여 렌즈없이도 격자선의 상이 만들어지는 이 현상은 흥미로울뿐만 아니라 회절격자를 사용한 미소거리의 측정에 응용될 수 있다. 본 연구에서는 간단한 Fraunhofer 근사를 사용해도 이러한 현상을 해석할 수 있음을 보였고 실험을 통하여 예측한 대로 특정한 영역에서 격자선 복제가 일어나는 것을 확인하였다.

• 대한의생명과학회지
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• 제25권1호
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• pp.54-59
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• 2019

Hepatitis refers to inflammation of hepatocytes and liver tissue, and is mainly caused by viruses, alcohol, and drugs. Forsythiae Fructus has traditionally been used as a diuretic, anti-inflammatory and antipyretic. Research on rengyolone, a bioactive substance extracted from Forsythiae Fructus, is rarely found in Korea and abroad. First, an acute animal toxicity test for rengyolone was conducted for the animal experiment. 4 week-old SD rats were injected intraperitoneally with acetaminophen for 2 weeks to induce chronic liver inflammation. Rengyolone was orally administered into two groups during 4 weeks: pre-inflammatory group and post-inflammatory group. Oral doses were also divided into 1 mg/kg and 5 mg/kg. Liver function tests (ALT, AST, ALP), western blot analysis of liver tissue, and level of inflammatory cytokine were performed to evaluate the improvement of hepatitis. Experimental results showed that rengyolone inhibited the development of acute inflammation and thus could reduce hepatitis symptoms.

• 한국위성정보통신학회논문지
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• 제12권4호
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• pp.115-119
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• 2017

상호변조왜곡은 원신호의 S/N도 악화시키고 인접채널에도 간섭 영향을 미친다. 상호변조왜곡은 전력증폭기의 비선형 특성에 의해서 주로 발생된다. 비선형 특성을 갖는 전력증폭기가 메모리 효과를 갖는다면 전력증폭기에서 발생되는 상호변조왜곡은 다양하고 복잡한 형태로 발생된다. 상호변조왜곡을 개선하는 방법으로 전치왜곡기가 주로 사용된다. 전치왜곡기의 성능을 충분하게 활용하기 위해서는 전력증폭기가 갖는 메모리 효과를 줄여야 한다. 본 논문에서는 전력증폭기에서 발생하는 메모리 효과를 줄이기 위한 바이어스 회로의 설계 방법에 대해서 기술하였다. 메모리 효과를 줄이기 위해서 바이어스 회로는 신호에 대해서는 높은 임피던스를 가져야 하며, 포락선(변조신호)에 대해서는 낮은 임피던스를 가져야 한다. 더불어 신호의 2차 고조파에 대해서도 낮은 임피던스를 가져야 한다. 메모리 효과를 고려해서 설계한 바이어스 회로의 성능을 확인해 보기 위해서 170 ~ 220MHz에서 동작하는 전력증폭기를 설계 및 구현하였다. 전력증폭기에 적용한 바이어스 회로는 동작주파수 대역에서 큰 임피던스를 가지며, 포락선 신호와 신호의 2차 고조파에서는 낮은 임피던스를 갖는다. 성능 측정결과 비대칭적으로 발생되는 상호변조왜곡 성분이 3.7dB 개선됨을 알 수 있었다.

• Nutritional Sciences
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• 제6권3호
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• pp.160-166
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• 2003

To examine the evidence that wheat bran is protective against breast cancer development and that its main mechanism of action is by modulating estrogen metabolism. This review explores the role of different experimental factors on the anticancer effects of wheat bran and the relationship of changes to estrogen metabolism by wheat bran on breast cancer risk The timing of the experimental diets in relation to carcinogen administration, the length of feeding of the experimental diets, and the level of dietary fat had an impact on the effectiveness of different doses of wheat bran in reducing breast carcinogenesis. Wheat bran supplementation resulted in significant reductions in human plasma estrogen levels but not in that of animals tested. The change in excretory metabolism of estrogen by wheat bran feeding in animals was not related to any of the tumor indices measured. The protective effect of wheat bran in breast carcinogenesis is greatest at the promotional phase and when supplemented in a high fat diet. Doses of wheat bran in the 9-12% range in diet have been consistently protective. The inconsistency observed with higher doses of wheat bran may be dependent on the animal model used. Although wheat bran's inhibitory effects on tumor growth may involve changes to estrogen metabolism, the fiber and phytochemical components of wheat bran may also act through estrogen-independent mechanisms. For a better understanding of the effect of wheat bran on breast carcinogenesis, studies comparing the effects of different wheat bran components both alone and in combination need to be performed.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권4호
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• pp.287-294
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• 2006

Vascular thrombosis and ischemic necrosis still remain the most significant threats to the survival of free flaps. To date, neutrophils have been implicated in the pathogenesis of postischemic injury. Several studies have demonstrated that modulating the neutrophil response to ischemia-reperfusion injury can decrease the extent of the injury. In addition, some authors noticed that mast cell counts were also increased in flaps exposed to state of ischemia/reperfusion. So, we designed to evaluate the role of mast cells in ischemia/reperfusion by blocking histamine and to compare the effect of L-arginine, a nitric oxide precursor which is known to prevent neutrophil-mediated tissue injury. Epigastric island skin flaps were elevated in 30 rats and rendered ischemic. Thirty minutes prior to reperfusion, the rats were treated with intraperitoneal saline, diphenhydramine, cimetidine, and L-arginine. The necrosis rate of flap at 7 days, the number of neutrophils and mast cells at 20 hours were evaluated. In conclusion, histamine receptor blockers as well as L-arginine significantly decreased flap necrosis in a rat skin island ischemia-reperfusion flap model, but the protective effect was not significantly different in both agent groups.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.177-177
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• 1996

Taurine Chloramine (Tau-Cl) inhibits production of nitric oxide(NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) in activated peritoneal macrophages, similar In that previously reported for activated RAW 264.7 cells. In addition, the effect of Tau-Cl and taurine on superoxide anion (O$\_$2/$\^$-/) Production in murine peritoneal exudate polymorphonuclear leukocytes (PMN) was examined. Tau-Cl inhibited O$\_$2/$\^$-/ production in a manner that was dose-dependent and reversible, Taurine also inhibited O$\_$2/$\^$-/ production by stimulated PMN, but at higher concentrations and to a lesser extent than Tau-Cl. The effects of taurine on O$\_$2/$\^$-/ production was attributed to the in vitro formation of Tau-Cl catalyzed by PMN associated halide-dependent myeloperoxidase. In contrast, production of NO and TNF-${\alpha}$ by activated peritoneal exudate macrophages was inhibited by Tau-Cl while taurine was without effect. These data lend support to the notion that Tau-Cl may participate ill the inflammatory responses by modulating production of inflammatory mediators.

• Journal of Nutrition and Health
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• 제30권9호
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• pp.1067-1072
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• 1997

One known effect of long chain n-3 polyunsaturated fatty acids is their ability to decrease plasma triglycerides. However, identification of the specific n-3 fatty acids and the underlying mechanisms responsible for this change remains uncertain. This present study was designed to evaluate the effects of moderate levels of dietary docosahexaenoic acid (22 :6(n-3)) on modulating plasma triglyderides. Male CD-1 mice were maintained for 15 days on identical diets containing either docosahexahexaenoic acid ethyl ester(1.5%, w/w) or linoleic acid(18 : 2(n-6)) ethyl ester (1.5%, w/w) . Plasma triglycerides were 40% lower in the docosahexaenoic acid group than in the linoleic acid group. Hepatic carnitine palmitoyltransferase activity (a key regulatory enzyme for mitocondria $\beta$-oxidation) was not significantly different between the dietary groups. However, plasma acid soluble acylcarnitine levels (which increase with increasing $\beta$-oxidation )were significantly higher in the decosahexaenoic acid group. This data suggests that plasma triglyceride levels are lower in mice fed diets containing moderate levels of docosahexaenoic acid compared to linoleic acid, but this effect on plasma triglycerides is not modulated through an augmentation of mitochondrial $\beta$-oxidation.

• Advances in Traditional Medicine
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• 제7권4호
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• pp.426-435
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• 2007

The present study was designed to determine the antitumor and antioxidant properties of methanol extract from the root of Galega purpurea (Papilionaceae) (MEGP) against Ehrlich Ascites Carcinoma (EAC) bearing Swiss albino mice. Acute and short-term toxicity studies were performed initially in order to ascertain the safety of MEGP. The effect of MEGP on the growth of transplantable murine tumor, life span of EAC bearing hosts and simultaneous alterations in the hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. The MEGP showed decrease in tumor volume, packed cell volume and viable cell count and increases the nonviable cell count and mean survival time thereby increasing life span of EAC tumor bearing mice. Hematological profile reverted to more or less normal levels in extract treated mice. Treatment with MEGP decreased the levels of lipid peroxidation and increased the levels of glutathione, superoxide dismutase and catalase. The results suggested that the methanol extract of Galega purpurea root exhibited antitumor effect by modulating lipid peroxidation and augmenting antioxidant defense system in EAC bearing mice.