• Journal of Biomedical Engineering Research
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• v.19 no.1
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• pp.81-90
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• 1998

Electromagnetic waves may induce various effects on nervous tissues either by thermal or non-thermal mechanisms. This paper intoduces a method to evalute the non-thermal effect to central nervous system by measuring the EEGs of the rabbits treated by nimodipine before exposed to weak microwave field. 20 rabbits were divided into 2 groups and their EEGs were measured after their head section were exposed to 2,450 MHz microwave with the power density of 10 dBm and 20 dBm respectively for 10 minutes and compared with those of the 3rd group of 10 rabbits which were not exposed. The 4th group of 10 rabbits were intravenously given with nimodipine before exposed to 20 dBm field to determine whether this drug would reverse the EEGs changes induced by weak microwave irradiation. As field poser exceeded 20 dBm although no significant physiological changes were observed, total induced EEGs power was remarkably decreased suggesting the presence of CNS activation. Using Fourier analysis on the EEGs signal it was found that remarkable decrease in delta band and increase in the alpha and beta bands in a significant manner(P<0.05) compared to control group. The changes were, however, not reversed by nimodipine-treatment. The effects may be pure thermal in nature because no significant change has been observed in nimodipine treated rabbits.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.1
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• pp.54-58
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• 2007

Purpose: Luciferase is one of the most commonly used reporter enzymes in the field of in vivo optical imaging. D-luciferin, the substrate for firefly luciferase has very high cost that allows this kind of experiment limited to small animals such as mice and rats. In this current study, we validated local injection of D-luciferin in the articular capsule for bioluminescence imaging in rabbits. Materials and Methods: Chondrocytes were cultured and infected by replication-defective adenoviral vector encoding firefly luciferase (Fluc). Chondrocytes expressing Fluc were injected or implanted in the left knee joint. The rabbits underwent optical imaging studies after local injection of D-luciferin at 1, 5, 7, 9 days after cellular administration. We sought whether optimal imaging signals was could be by a cooled CCD camera after local injection of D-luciferin. Results: Imaging signal was not observed from the left knee joint after intraperitoneal injection of D-luciferin (15 mg/kg), whereas it was observed after intraarticular injection. Photon intensity from the left knee joint of rabbits was compared between cell injected and implanted groups after intraarticular injection of D-luciferin. During the period of imaging studies, photon intensity of the cell implanted group was 5-10 times higher than that of the cell injected group. Conclusion: We successfully imaged chondrocytes expressing Fluc after intraarticular injection of D-luciferin. This technique may be further applied to develop new drugs for knee joint disease.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.4
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• pp.280-286
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• 2016

Polyphenols have been reported to have beneficial effects on cardiovascular disease. A polyphenolic compound, 3,4-dihydroxy-hydrocinnamic acid (3,4-DHHCA), has been shown to have antioxidative and antitumorigenic activities. However, the effect of 3,4-DHHCA on atherosclerosis is still unknown. Herein, we investigated the effects of 3,4-DHHCA on atherosclerosis in New Zealand White rabbits. Broad and fused fatty streak lesions were found in rabbits fed with high-cholesterol diet for 8 weeks. Administration of 3,4-DHHCA reduced atherosclerotic lesion formation and lesional accumulation of macrophage in rabbits fed with cholesterol diet without systemic or local toxicity. Hepatic acyl-coenzyme A: cholesterol acyltransferase (ACAT) activity was decreased after treatment with 3,4-DHHCA by 22% in cholesterol diet-fed rabbits compared with the control group. These results indicate that 3,4-DHHCA had antiatherogenic effects in rabbits, possibly by partial inhibition of ACAT.

• Korean Journal of Ecology and Environment
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• v.51 no.4
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• pp.345-353
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• 2018

Hibernation is regarded as a physiological and behavioral adaptation that permits the survival of animals such as bats during seasonal periods of energy shortage. This study investigated the hibernation period of Plecotus ognevi in the temperate climate zone and the relationship between the thermal preference and hibernating process of bats. We hypothesized that the hibernation period of bats is closely related to the external temperature and temperature preference of bat species in the temperate region. To verify this hypothesis, we surveyed the distribution of the P. ognevi population in South Korea, and the temperature preference and the characteristics of hibernacula of P. ognevi. We predict that hibernation in the bat will begin when the external temperature drops below the thermal preference of the species and will leave from hibernation when the external temperature is higher than the thermal preference. P. ognevi hibernated in roosts maintained in low temperature ambient conditions with $-3.5{\sim}7.5^{\circ}C$). The body temperatures (averaged $3.01{\pm}1.30^{\circ}C$, ranged $0.1{\sim}7.8^{\circ}C$) of hibernating bats were closely related to the rock surface temperatures rather than the ambient temperatures. The bats began to hibernate in late November and final arousals occurred in mid-March, so that the total length of the hibernation was 115~120 days. The period of hibernation was strongly influenced by fluctuations in the external mean temperature. This study suggests that the onset and termination of P. ognevi hibernation is due to the interaction between the temperature of the hibernacula and that of the external environment and is based on the thermal preference of the bats. The study also suggests that the hibernation strategy such as thermal preference and hibernation periods of this species affect to distribution as bat species adapting to a severely climate.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.601-612
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• 2021

This study was conducted to evaluate the appropriate sowing method and mixture seeding rate on germination of Kentucky bluegrass (Poa pratensis L.) and white clover (Trifolium repens L.). The experimental design includes two sowing methods and six mixed seeding per each method: BT₁:BP₀ (broadcast seeding; B, Trifolium repens; T, Poa pratensis; P), BT₁:BP₂, BT₁:BP₃, BT₃:BT₁, BT₂:BP₁, BT₀:BP₁ and ST₁:SP₀ (spot seeding; S), ST₁:SP₂, ST₁:SP₃, ST₃:ST₁, ST₂:SP₁, ST₀:SP₁. The germination was the highest for both species when the seeding rate was higher than other species. In overall, the germination of white clover was higher and faster than Kentucky bluegrass. Two plots, BT₂:BP₁, ST₁:ST₂, were retained the balanced proportion of the germination rate. Therefore, It was suggested, for maintaining the balanced field, it is better to seed white clover twice Kentucky bluegrass on broadcast seeding and Kentucky bluegrass twice white clover on spot seeding. In regard of sowing method, broadcast seeding is better than spot seeding in terms of increasing the germination. It is necessary to supplement the result for real application by long-term monitoring.

• The Korean Journal of Pharmacology
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• v.31 no.1 s.57
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• pp.85-93
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• 1995

In order to examine the effect of testosterone of the cell growth, using a primary rabbit kidney proximal tubule cell culture system, we observed the effect of 3 growth factors and testosterone supplementation on the growth of primary rabbit kidney proximal tubule cells in the serum-free medium. 1 nM of testosterone showed a potentiation of the effect on the growth of the proximal tubule cell in serum-free medium, but higher concentration (>10 nM) of testosterone indeed inhibited the growth. In the absence of hydrocortisone as a growth supplement in serum-free medium, testosterone caused to potentiate the growth of the cell. In the presence of hydrocortisone, testosterone also potentiated the grwoth of the proximal tubule cells. According to the Northern analysis, testosterone increased significantly the level of ${\beta}-actin$ mRNA in proximal tubular cells of rabbit kidney. Consequently we may suggest that growth stimulatory effect of testosterone on the primary rabbit kidney proximal tubule cell in serum-free and hormonally defined media ascribed to increase the synthesis of ${\beta}-actin$, which is an important protein consisting of cellular microfilament.

• Korean Journal of Veterinary Research
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• v.42 no.3
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• pp.411-418
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• 2002

Thirty rabbits underwent femoral lengthening using monolateral external fixator to evaluate results and complications of limb lengthening. Twenty rabbits survived until consolidation of callus formed at the lengthening site after finishing lengthening. Ten rabbits were sacrificed during femoral lengthening because of complications. Survived 20 rabbits were classified to two groups according the amount of lengthening: group I (10% lengthening of the femoral length); group II (20% lengthening). There was no significant difference of consolidation time between two groups (p=0.25). Varus angulation at the lengthening site occurred in 60% of two groups and the amount of varus angulation in group II was larger than that of group I. Degenerative change of articular cartilage at the medial condyle of the distal femur was found in 30% of group II. Of sacrificed ten rabbits, 5 had pin loosenings with pull an of pins from the femur, 2 had fermoral fractures around the pin-tract site, and 3 had severe osteomyelitis of the femur around the pin-tract site.

• Journal of Life Science
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• v.19 no.11
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• pp.1499-1505
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• 2009

This study was carried out between August and September 2007 to determine the causative agents and epidemiologic features of rabbit dermatitis in Korea. Rabbits were shipped to the laboratory in the College of Veterinary Medicine from 10 rabbit farms. A total of 520 hair, blood, and skin specimens collected from skin lesions of 40 rabbits with suspected dermatopathy were examined mycologically, bacteriologically, and parasitologically. The positive rates of dermatophytosis, bacterial skin dermatitis, and ectoparasite dermatitis were 95, 92.5, and 7.5%, respectively. The etiologic agents of dermatophytosis were identified as Trichophyton mentagrophyte (95%), non-dermatophytic filamentous fungi such as Aspergillus s(5%), and Cryptococcus humilocus (2.5%). With respect to bacteria-related skin dermatitis, Staphylococcus coagulase negative was the most common etiological agent. Staphylococcus aureus was the second most frequent causative agent. Most of the pathogenic isolates were resistant to tetracycline, and aminoglycosides such as amikacin and gentamicin were the most effective drugs against the pathologic bacteria isolated. Ectoparasites were rarely detected in this study. Only Psoroptes cuniculis was detected in 3 (7.5%) out of the 40 tested rabbits. The role of ectoparasites as a causative agent of dermatitis in rabbits in this study was minimal. Our results provide important information related to rabbit dermatitis treatments and researches.

• The Journal of Internal Korean Medicine
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• v.22 no.1
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• pp.21-27
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• 2001

목적 : 본 연구는 배기음(排氣飮)이 토끼의 위장관내에서 화학물질에 의해 유발된 장관의 궤양에 유효한 효과를 발휘할 수 있는지를 검증하기 위한 실험이다. 방법 : 토끼 5마리를 한 군으로 하여 정상군과 체중 1kg당 200mg 분량의 mepirizole을 경구 투여한 군과 100mg/kg의 배기음(排氣飮)(경구투여)과 800Units/kg 분량의 catalase(정맥주사)를 mepirizole을 경구투여하기 2시간 전에 각각 전처치한 군으로 나누었다. Mepirizole을 경구 투여한 후 각각 24hr와 48hr에 토끼를 희생시켜 위장, 십이지장부의 궤양성 병변을 관찰하였다. 결과 : Mepirizole을 경구투여하여 위장 및 십이지장 기부의 궤양성 병변이 유발되었다. 배기음(排氣飮)(경구투여)과 catalase(정맥주사)를 전처치하였을 경우 궤양의 크기가 현저하게 줄어들었다. Mepirizole은 십이지장 점막에서 지질의 과산화를 증가시키는데 이는 수산화기와 관련되어 있음을 시사한다. 배기음(排氣飮)과 catalase를 전처치함으로써 mepirizole에 의해 유발된 지질의 과산화가 현저하게 억제되었다. 형태학상의 연구에서도 mepirizole의 처치에 의한 십이지장의 손상과 배기음(排氣飮)에 의한 방지효과가 나타났다. 결론 : 이러한 결과들로 볼 때 반응성산소기는 mepirizole에 의해 유발된 위장관 궤양의 병리변화 형성에 주요한 영향을 미치며 배기음(排氣飮)이 항산화작용을 통해 궤양의 형성을 억제하는 역할을 하고 있음을 나타낸다. 따라서 본 연구는 배기음(排氣飮)이 반응성산소기에 의해 매개된 인체 위장관질환에 치료적 역할을 할 수 있음을 제시하고 있다.

• Journal of Embryo Transfer
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• v.12 no.3
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• pp.253-258
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• 1997

토끼에서는 수정란 이식과 같은 기본적인 번식공학적 방법의 효율성이 아직 생쥐와 같은 실험동물에 비해 떨어지고 있어 생물공학적인 기술을 응용하는데 큰 어려움이 있다. 특히 유전자 이식에 의한 형질전환 토끼의 생산과 같은 생물공학적인 기술을 실용화하는데 효율이 높은 수정란이식 기술의 개발이 필수적이라고 할 수 있다. 본 연구에서는 토끼에서 수정란 이식 기술의 첫 단계인 과배란 유도를 효율적으로 이용할 수 있는 방법을 정립하기 위해 반복적인 과배란 유도가 배란율 및 수정란의 질적인 면과 양적인 면에 미치는 영향을 조사하였다. 연구방법으로는 FSH와 HCG를 사용하여 과배란을 유도하였고 2.5 개월의 반복처리간격으로 3번의 반복적인 과배란 처리를 한 후 반복처리에 따른 배란율과 배란된 난자의 형태학적 상태, 배양에 의한 발생 능력 상태 등을 감소하였으며 배란수의 변이도 커지는 경향을 나타내었다(첫번째, 32.6(+-)2.5; 두번째 28.7(+-)3.7; 세번째 20.99(+-)3.8). 제 2극체의 돌출, 전핵의 형성, cummulus cell의 존재등에 의한 회수된 난자의 형태학적 관찰에 의한 방법으로 난자를 분류한 결과 과배란의 반복수가 증가함에 따라 다양한 모양의 난자가 회수되어 배란이 광범위한 시간대에 일어나고 있음을 나타내었다. 또한 과배란의 반복적인 유도에 의해 난소의 혈포수는 증가하였으나 채란된 난자의 채외배양에 의한 발육율에는 차이가 없었다. 그러므로 과배란의 반복적인 유도는 공란토의 난소반응에는 영향을 미쳤으나 난자의 질에는 영향을 미치지 않았음을 나타낸다.