• Korean Journal of Veterinary Pathology
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• v.1 no.2
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• pp.135-138
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• 1997

A pulmonary keratinizing cyst was found incidentally in a 30-week-old female Sprague-Dawley rat. The cyst was lobe of the lung, lined by stratified squamous epithelium and filled with concentric layers of desquamated keratin. The wall consisted of 2-4 layers of well differenciated squamous cells. The adjacent lung tissues were slightly compressed but not otherwise damaged by the cyst. There was no inflammatory reaction or mitotic figures observed in the cyst.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.3
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• pp.89-94
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• 2008

In order to reproduce chronic cerebral hypoperfusion as it occurs in human aging and Alzheimer's disease, we introduced permanent, bilateral occlusion of the common carotid arteries (BCCAO) in rats (Farkas et al, 2007). Here, we induced BCCAO in two different rat strains in order to determine whether there was a strain difference in the pathogenic response to BCCAO. Male Wistar and Sprague-Dawley (SD) rats (250-270 g) were subjected to BCCAO for three weeks. Kluver-Barrera and cresyl violet staining were used to evaluate white matter and gray matter damage, respectively. Wistar rats had a considerably higher mortality rate (four of 14 rats) as compared to SD rats (one of 15 rats) following BCCAO. Complete loss of pupillary light reflex occurred in all Wistar rats that survived, but loss of pupillary light reflex did not occur at all in SD rats. Moreover, BCCAO induced marked vacuolation in the optic tract of Wistar rats as compared to SD rats. In contrast, SD rats showed fewer CA1 hippocampal neurons than Wistar rats following BCCAO. These results suggest that the neuropathological process induced by BCCAO takes place in a region-specific pattern that varies according to the strain of rat involved.

• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.245-250
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• 1992

This study was performed to demonstrate the presence of large granular lymphocyte(LGL) in Sprague-Dawley(SD) rats and morphologically observe NK cell and also establish the method of isolation of natural killer cell in SD rats. By percoll discontinuous density gradients centrifugation, highly enriched LGL population were shown to fraction 2(border line between 44.2% and 50.8%). LGL were shown to bind selectively to YAC1 mouse lymphoma cell. This fraction expressed very high NK cell cytolysis. Therefore, we thought that LGL have NK activity in SD rats. The Morphology of rat LGL is very similar to that of human LGL. These cells have an eccentric kidney-shaped nucleus. Their most distinctive feature was their cytoplasmic azurophilic granules. Another distinguishing feature of rat LGL was their high cytoplasmic : nuclear ratio. It was concluded that LGL played a role part in mediating natural killer activity in this species.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.12
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• pp.1087-1092
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• 2007

We developed the 4-channel Light Medical Therapy Apparatus for Skin Injury Cure using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity and reservation. In this paper, the designed device was used to find out how high brightness LED light affects the skin injury of SD-Rat(Sprague-Dawley Rat). In the experiment, $1\;cm^2$ wounds on the skin injury of SD-Rat(Sprague-Dawley Rat) were made. Light irradiation group and none light irradiation group divided, each group was irradiated one hour a day for 14 days. In result, compared with none light irradiation group, the lower incidence of inflammation and faster recovery was shown in light irradiation group.

• Childhood Kidney Diseases
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• v.3 no.1
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• pp.20-26
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• 1999

Purpose : Several modulatory factors for renal peripheral benzodiazepine receptor (PBR) has been reported, but their physiological significance remains elusive. Tissue-specific, stress-induced down-regulation of renal PBR coupled with the pharmacological stimulation of these effects by angiotensin II suggested that physiological significance of renal PBR may be related to the pathophysiology of stress-induced hypertension. The boderline hypertensive rat (BHR) has been used extensively to study the interaction of environmental factors, such as stress and blood pressure. The BHR is the first-generation progeny of a cross between the spontaneously hypertensive rat and the control Wistar-Kyoto rat. The pathogenesis of stress induced hypertension in this model is not demonstrated well. Methods In this study, BHR (male, 150-200 g) and Sprague-Dawley (SD, male, 150-200 g) rats were treated by repeated immobilization to induce anxiety. We used plus-maze performance to observe the level of anxiety by measuring percent open crosses and percent time in open. Results : Percent open crosses and percent time in open in BHR were lower than in SD rats (P<0.05). Receptor densities of renal PBR in BHRs were significantly lower than those of SDs (P<0.05). We also observed that the renal PBR was upregulated in the repeatedly stressed (immobilization, 2 hours daily, for 2 weeks) rats, both in the BHR and SD. However, the density of renal PBR in the stressed BHR was still lower than that of stressed SD. Renal PBR has been suggested to be an important organs which Is responsible for the production of cholesterol-derived products during stress. Conrlusion : From these results, it can be summarized that the lowed density of renal PBR may be involved in the pathogeneis of stress-induced hypertension.

• Toxicological Research
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• v.17 no.2
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• pp.83-90
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• 2001

The background control data were compiled from rat developmental toxicity studies con-ducted at Toxicology Research Center, KRICT during the 1993-1999 period. These data were assembled in order to provide background in formation for the maternal and fetal data collected in 13 developmental toxicity studies using Sprague-Dawley rats. A total of 325 mated females were used in these studies during the seven-year period and overall pregnancy rate of these females was 93.8%. The present background control data included body weights, food consumption, hematological values, and organ weights of pregnant females, caesarean section data, and fetal examination data. These data can be used not only as a historical database for the meaningful interpretation of data from reproductive and developmental toxicity studies, but also as a contribution to biological characterization oj Sprague-Dawley rats.

• Korean Journal of Veterinary Pathology
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• v.2 no.1
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• pp.47-52
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• 1998

The incidence of spontaneous testicular atrophy and its morphological changes during stage-specific spermatogenesis were investigated in male Sprague-Dawley rats at 10, 19, and 32 weeks of age. The incidence of testicular atrophy was 0.2%(2/90) 7.9%(9/114) and 10%(4/40) in 4, 13 and 26 weeks respectively. The epididymis with testicular atrophy had low sperm density. In the minimally affected tests scattered tubules showed complete depletion of germ cells without stage specificity. Testes with moderate to severe testicular atrophy showed seminiferous tubules lined with dense Sertoli cell population. While Leydig cells in the interstitium appeared hypertrophy they were immunohistochemically negative for proliferating cell nuclear antigen a marker of cell proliferation.

• Development and Reproduction
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• v.2 no.2
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• pp.135-140
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• 1998

Protease Nexin-1 (PN-1) inhibits the activity of several serine proteases including thrombin, urokinase (uPA)-type plasminogen activator and trypsin. Tissue- and reproductive organ-specific mRNA levels of the PN-1 were investigated in Sprague-Dawley adult rat. PN-1 mRNA expression in rats was found in brain (forebrain, hindbrain), heart, liver, lung, ovary and oviduct. The level of PN-1 mRNA in male and female among the tissues was the highest in forebrain of the female. PN-1 expression in reproductive organs was found only in ovary and oviduct. These results suggest that PN-1 expression is dependent on the sex and may be related to folliculogenesis and early embryogenesis.

• The Journal of Korean Physical Therapy
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• v.2 no.1
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• pp.47-63
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• 1990

The purpose of this study was to determined the effect of low-frequency electrical stimulation on the denervated gastrocnemius muscles of the albino rats, Sprague-Dawley. Fifteen Sprague-Dawley adult male albino rats were divided into non-treated (normal) group, denervated (control) group, denervated and electrical stimulated (experiments). The gastrocnemius muscles of the right leg were submaximally stimulated with 30 Hz electrical stimulation. After 4-week period, the animals were sacrificed, and muscle were removed, fixed by immersion, and processed for light and electron microscopy. The numbers of Ag-NOR increased significantly (p<0.001), but significant reductions of girth(p<0.01), wet muscle weight (p<0.001), high glycogen content fiber (p<0.01), and mitochondrial number (p<0.05) were found in denervated control group. In comparison with control group, significant increase of right leg girth (p<0.05), wet muscle weight (p<0.001), high glycogen content fiber (p<0.05), numbers of Ag-NOR(p<0.001), number of mitochondria (p<0.01), mitochondrial volume found in electrical stimulated experimental group. The results suggest that the electrical stimulation of the muscle partially prevented the denervated atrophy in the rat gastrocnemius muscles.

• Transactions on Electrical and Electronic Materials
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• v.9 no.3
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• pp.116-119
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• 2008

The purpose of this study is to develop the Photodynamic Therapy Equipment for medical treatment. We developed the equipment which was helpful in palpating wound healing by using 525 nm LEDs. The equipment was assembled with a micro-controller and green color LEDs, and designed to enable us to control light irradiation time, intensity and so on. In this study, the designed device was used to find out how 525 nm LEDs light affected the skin wound of SD-Rat(Sprague-Dawley Rat). We divided the participants into two groups; irradiation group which was irradiated one hour a day for 9 consecutive days, and none irradiation group. The results showed that the study group had lower incidence of inflammation and faster recovery, compared with the control group.