• Animal cells and systems
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• 제6권3호
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• pp.253-261
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• 2002

Although cardiac distribution of specific receptors for atrial natriuretic peptide (ANP) was mainly observed in the ventricular endocardium, the modulation of ANP receptors in relation to cardiac development is not defined. The present study was undertaken to investigate ANP receptor modulation in rat during development. In the developmental stages examined (fetus, after postnatal 3-days, 1-, 2-, 3-, 4-, and 8-week-old Sprague Dawley rats) specific ANP binding sites were localized in the right and left ventricular endo-cardia by quantitative in vitro receptor autoradiography using (equation omitted)-rat ANP as labeled ligand. The specific bindings to endocardium were much higher in the right than the left ventricle. The binding affinities of ANP were much higher in the right than the left ventricular endocardium. The difference of these binding affinities among various developmental stages was not observed in the right ventricle, whereas the binding affinity in left ventricle was gradually increased with aging and reached the peak value at 8 weeks. No significant difference in maximal binding capacities of endocardial bindings was observed in the right and left ventricular endocardia during developmental stages. Also, cGMP production via activation of particulate guanylyl cyclase-coupled receptor subtypes in the ventricular membranes was gradually decreased with close relationship to aging. Therefore, the present study show that the endocardial ANP receptor is modulated with close relationship to cardiac development in the left ventricle rather than the right ventricle, and may be involved in regulating myocardial contractility in left heart.

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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• pp.1746-1753
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• 2007

Steers (n = 335) of known genetic background from four fundamentally different growth types were subjected to two production systems to study differences in cooking loss (CL), tenderness, and chemical composition. Growth types were animals with genetic potential for large mature weight-late maturing (LL), intermediate mature weight-late maturing (IL), intermediate mature weight -early maturing (IE), and small mature weight-early maturing (SE). Each year, in a nine-year study, calves of each growth type were weaned and five steers of each growth type were developed on pasture or feedlot and harvested at approximately 20 and 14 mo of age, respectively. Data collected were CL and Warner-Bratzler shear force (WBS) for the Longissimus dorsi (LM), Psoas major (PS), and Quadriceps femoris (QF) muscles. Chemical composition was also determined from the right fore- and hindquarter. Data were analyzed using least squares analysis of variance for unequal subclass numbers. The beef growth $type{\times}production$ system interaction was significant for CL and WBS of the LM and ash in the lean trim of the forequarter. Growth types of LL and IL had greater (p<0.05) mean percentage CL in the PS and QF muscles than did IE and SE steers. Growth type LL had the highest (p<0.05) mean for both moisture and protein in the fore- and hindquarters; while SE had the lowest numerical mean value for moisture and protein in the fore- and hindquarters. Shear force of the PS did not differ (p>0.05) among steers of the four growth types. Increasing challenges to the cattle feeding industry may dictate that pasture development play a larger role in future production regimes. Producers should strive to match genetic growth type with available resources in order to remain viable and continue producing a quality product.

• 한국임상수의학회지
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• 제30권6호
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• pp.468-472
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• 2013

12연령의 암컷 잡종개 (체중 6.2 kg)가 심한 복부 팽만, 지속적 기침 그리고 운동 불내성을 주증으로 진료 의뢰 되었다. 진단상에 복수, 경정맥 노장, 심한 좌우 심첨부 수축기 잡음 (4/6 단계), 후대정맥 확장을 동반한 전반적 심비대와 좌심방 확장이 관찰되었다. 심장 초음파에서는 퇴행성 이첨판막 그리고 삼첨판막 심내막증과 양심실성 울혈성 심부전이 관찰되었다. 좌우단락의 난원공 개존증 또한 있었다. 좌심실 수축능은 용적 과부하의 정도와 관계되어 떨어져 있었다. 진단적 결과에 기초하여, 본 증례는 ISACHC IIIa 심부전의 이첨판막과 삼첨판막 심내막증이 합병된 난원공 개존증으로 진단되었다. 이 개는 푸로세마이드 (2 mg/kg, q12hr, PO), 피모벤단 (0.3 mg/kg, q12hr, PO)와 스피로노락톤 (1 mg/kg, q12hr)으로 치료되었다. 임상 증상들은 약물 치료 후에 점차적으로 개선되었다.

• 한국수정란이식학회지
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• 제31권4호
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• pp.313-318
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• 2016

The aim of this study was to identify quantitative trait loci (QTLs) influencing teat number traits in an $F_2$ intercross between Landrace and Korean native pigs (KNP). Three teat number traits (left;right;and total) were measured in 1105 $F_2$ progeny. All experimental animals were genotyped with 173 informative microsatellite markers located throughout the pig genome. We detect that seven chromosomes harbored QTLs for teat number traits: genome regions on SSC1;3;7;8;10;11;and 13. Six of fourteen identified QTL reached genome-wide significance. In SSC7;we identified a major QTL affecting total teat number that accounted for 5.6 % of the phenotypic variance;which was the highest test statistic (F-ratio = 61.1 under the additive model;nominal $P=1.3{\times}10^{-14}$) observed in this study. In this region;QTL for left and right teat number were also detected with genome-wide significance. With exception of the QTL in SSC10;the allele from KNP in all 6 identified QTLs was associated with decreased phenotypic values. In conclusion;our study identified both previously reported and novel QTL affecting teat number traits. These results can play an important role in determining the genetic structure underlying the variation of teat number in pigs.

• 한국방사선학회논문지
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• 제8권7호
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• pp.389-395
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• 2014

본 연구는 교모세포종 (Glioblastoma multiform, GBM)에 대한 방사선 진단학적/치료학적 연구에 필수적으로 필요한 악성뇌종양 동물모델을 개발하기 위해 수행되었다. 악성뇌종양 동물모델 개발을 위해 뇌정위 기구(stereotactic instrument)를 이용하여 C6 세포(Glioblastoma cell line)를 SD rat의 우측 선조체 내에 동종이식하였다. 개발된 동물모델의 검증을 위해 MRI와 해부조직학적 검사방법을 이용하였다. 해부조직학적 검사방법으로는 H&E 염색법을 이용하였다. MRI를 이용한 종양 형성 검사에서 C6 세포 이식 7일 후 종양 형성이 확인되었고, 14일 후에는 이식한 우측 뇌의 대부분이 종양으로 변화한 것을 확인하였다. 해부조직학적 검사에서는 과세포 발현 및 다형성 세포에 의해 형태학적 변화가 발생하는 것을 알 수 있었다. 본 연구에서 개발된 악성뇌종양 동물모델은 in vivo level에서 교모세포종에 대한 방사선 진단학적 기술 개발 및 새로운 치료법 개발을 위한 필수적인 도구로서 활용될 수 있을 것이다.

• 한국임상수의학회지
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• 제31권6호
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• pp.507-510
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• 2014

8개월령 암컷 포메라니안 개가 심잡음과 심비대를 주호소로 내원하였다. 검사결과 좌-우단락 동맥관 개존증과 중등도의 심부전 (ISACHC II) 으로 진단되었다. 잔존 동맥관은 우측 대퇴동맥을 통한 $5mm{\times}3loops$ 코일 색전술을 통해 성공적으로 치료되었다. 2개월 후 환축은 현저한 저혈압과 심한 설사, 흉수가 차는 증상으로 다시 내원하였다. 검사 결과 심각한 폐성고혈압과 삼첨판 역류가 발견되었다. Sildenafil (3 mg/kg, PO, TID) 을 투여함으로써 임상증상은 조절되었으나, 코일빠짐과 보호자의 부적절한 투약으로 인해 환축은 폐사하였다. 부검 결과 폐성고혈압의 원인은 비정상적인 위치로 빠진 색전 코일에 의한 것으로 밝혀졌다. 토이 품종에서 PDA의 치료를 위해 색전 코일이 널리 사용되고 있지만, 장착된 코일이 빠질 위험을 줄이기 위해서는 PDA의 크기와 형태에 대한 한층 더 세심한 평가가 필요하다.

• Restorative Dentistry and Endodontics
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• 제48권1호
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• pp.9.1-9.11
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• 2023

Objectives: This study evaluated the effect of adjacent gingival blood flow on detection of pulpal blood flow (PBF) using ultrasound Doppler flowmetry (UDF) through animal study. Materials and Methods: The study included 36 right and left maxillary the third incisors and canines in 9 experimental dogs. The study included 2 main steps: In the first step, the pulse sound level (PSL) was recorded on the cervical part of each tooth without flap elevation (Group 1), with flap elevation (Group 2), and after it was repositioned in place (Group 3). In the second step, the PSL was recorded on the cervical part of each tooth (Group 4), after pulpotomy (Group 5), after partial pulp extirpation (Group 6), after complete extirpation (Group 7), and after canal filling (Group 8). In Groups 5-8, the study was performed with and without flap elevation in the left and right teeth, respectively. The PSL was graded as follows: 0, inaudible; 1, heard faintly; and 2, heard well. The difference between each group was analyzed using Friedman's test with Wilcoxon signed-rank tests (α = 0.05). Results: In step 1, the PSL results were Group 1 > 2 and 3. In step 2, there was no significant difference between the groups when the flap was not elevated, while PSL results were Group 4 > 5 ≥ 6 and 7 ≥ 8 when the flap was elevated. Conclusions: PBF is affected by gingival blood flow when measured with UDF. UDF measurements require isolation of gingiva from the tooth.

• 대한치과교정학회지
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• 제23권4호
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• pp.503-527
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• 1993

This paper describes a new method to create an animal model for TMJ internal derangement in the New Zealand white rabbits and the light and electron microscopical changes of posterior attachment of them. Twenty six rabbits(2.5-3.0kg), four normal and twenty two experimental, were used. The right disc of experimental animal was displaced anteriorly without sectioning the posterior attachment and tied to the zygomatic arch with nylon not to be reduced to the original position. The left TMJ was sham-operated to be compared with its right experimental one. Normal animals were sacrificed one day and eight weeks after experiment. Experimental animals were sacrificed one day, ten days, three weeks, five weeks and eight weeks after surgery respectively. They were fixed intravenously with $2\%$ glutaldehyde under general anesthesia and the samples of them were processed for light and electron microscopic examination. The purpose of this experiment is to make a suitable animal model of disc displacement without reduction for studying and understanding the cellular and morphologic events in posterior attachment of TMJ including early changes which were difficult to be observed in human TMJs. The results of this investigation suggest the following conclusions : 1. Authors induced anterior disc displacement surgically in rabbits with new method to examine histologic changes of posterior attachment. Tissue reactions of this model seem to be similar to those observed in human disc displacement. We think this animal model for anterior disc displacement may be used to explore and evaluate objectively the effects of many treatment modalities in disc displacements. 2. The animal disease model showed inflammation at early stage(one and ten days). At this stage there were mild-to-severe mononuclear inflammatory cell infiltration, numerous newly formed vessels, vessel dilatation and engormement and many fibroblasts. 3. At middle stage(three weeks), fibrosis occurred, where fibroblasts decreased in number, but their cytoplasm was profuse indicating high activity. Collagen fibers increased in number and the tissue looked more dense. 4. At late stage(five weeks and eight weeks) showed degenerative changes including perforation of posterior attachment, disintegration of collagen fiber bundles, degeneration of fibroblasts, metastatic ossification, and dystrophic calcification.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권4호
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• pp.240-249
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• 2020

Objectives: Although the side effects of radiation therapy vary from mucositis to osteomyelitis depending on the dose of radiation therapy, to date, an experimental animal model has not yet been proposed. The aim of this study was to develop an animal model for assessing complications of irradiated bone, especially to quantify the dose of radiation needed to develop a rat model. Materials and Methods: Sixteen Sprague-Dawley rats aged seven weeks with a mean weight of 267.59 g were used. Atraumatic extraction of a right mandibular first molar was performed. At one week after the extraction, the rats were randomized into four groups and received a single dose of external radiation administered to the right lower jaw at a level of 14, 16, 18, or 20 Gy, respectively. Clinical alopecia with body weight changes were compared and bony volumetric analysis with micro-computed tomography (CT), histologic analysis with H&E were performed. Results: The progression of the skin alopecia was different depending on the irradiation dose. Micro-CT parameters including bone volume, bone volume/tissue volume, bone mineral density, and trabecular spaces, showed no significant differences. The progression of osteoradionecrosis (ORN) along with that of inflammation, fibrosis, and bone resorption, was found with increased osteoclast or fibrosis in the radiated group. As the radiation dose increases, osteoclast numbers begin to decrease and osteoclast tends to increase. Osteoclasts respond more sensitively to the radiation dose, and osteoblasts are degraded at doses above 18 Gy. Conclusion: A standardized animal model clinically comparable to ORN of the jaw is a valuable tool that can be used to examine the pathophysiology of the disease and trial any potential treatment modalities. We present a methodology for the use of an experimental rat model that incorporates a guideline regarding radiation dose.

• 한국가축번식학회지
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• 제22권1호
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• pp.67-72
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• 1998

Nowadays many kinds of foreign breed horse and Korean native Cheju horse are raised in Korea. Horse has complicated structure and function to maintain normal health, and to overcome severe condition during gallop at full speed. Sometimes the disease take a bad turn becuase of difficulty of correct diagnosis for horse disease. In recent times, horse farm for fattening and reproduction is gradually increasing. However, thoracic disease and abdominal disease are frequently occuring by defect in raising management. But the diagnosis of these kinds of disease is difficult by former diagnostic method. Ultrasonographic diagnostic method is a method to slove the problem. In abroad, nowadays ultrasonography has been reported for circulatory organs and abdomonal organs in horse, cattle, sheep, and dog, and the importance of ultrasonographic diagnosis is recognized in veterinary clinical medicine. In the country, ultrasonography of Korean native goat, cattle and dog was recently reported, but there was no report for the ultrasonography of horse. So, ultrasonogram for the thyroid glands, jugular vein and carotid artery was evaluated in Cheju horse and Thoroughbred horse. Thyroid gland, jugular vein and carotid artery were determined on both sides of neck. The length of right thyroid lobe at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 54.8, 45.1, 46.1 and 42.2 mm, respectively. The width of right thyroid lobe at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 18.1, 14.3, 14.6 and 14.2 mm, respectively. The height of right thyroid lobe at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 27.3, 25.6, 26.2 and 25.5 mm, respectively. Similar ultrasonographic measurements were obtained for the left thyroid gland. The internal diameter of left jugular vein at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 10.6, 9.7, 10.5 and 9.2 mm, respectively. Similar ultrasonographic measurements were obtained for the right jugular vein. The internal diameter of right carotid artery at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 9.5, 8.8, 9.1 and 8.5 mm, respectively. Similar ultrasonographic measurements were obtained for the left carotid artery. It is concluded that the ultrasonographic values of this study provides references for the diagnosis of morphologic changes in the thyroid gland, jugular vein and carotid artery in Korean native Cheju horse and Thoroughbred horse.