• Title/Summary/Keyword: 비정상 전도

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General Activity and Stress Response of Rats Following Removal of the Mamillary Bodies (유두체를 떼어버린 흰쥐의 일반활동 및 스트레스에 대한 반응)

  • Kim, Chul;Choi, Hyun;Kim, Chung-Chin;Kim, Jong-Kyu;Kim, Myung-Suk
    • The Korean Journal of Physiology
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    • v.2 no.1
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    • pp.79-88
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    • 1968
  • For the purpose of assessing the influence of the mamillary bodies on the general activity and stress response, mamillary body·damaged rats(mamillary body group), operated control rats, and normal control animals were prepared and 2 experiments were carried out. The mamillary bodies. were damaged electrolytically by passing 0.3 ma d.c. current through stereotaxically implanted electrodes. The operated control group received the same treatment except passage of current. In the 1st experiment, each subject belonging to the mamillary body group .(9 rats) or the operated control group (13 animals) was put individually into an activity cage across which an infrared beam traversed. The number of beam interruptions by the movement of the subject in the cage was. recorded hourly for 48 hours and was regarded as an index of general activity. In the 2nd experiment, each of the mamillary body group (52 animals), the operated control group (45 rats), and the normal control group (37 animals) was further divided into 4 subgroups and the adrenal ascorbic acid content of one of the 4 subgroups was measured before, another subgroup immediately after, a third subgroup 2 hours after, and the remaining subgroup 4 hours after termination of a cold stress ($-10^{\circ}C$ for 1 hour). Following results were obtained: 1. Though the total activities in 48 hours of the mamillary body group and the operated control group were not significantly different, the activities of the malnillary body group for a few hours. at the beginning of the measurement and also in the evenings of both the 1st and the 2nd experimental days were significantly greater than those of the operated control group. 2. Judged by the significant reduction in adrenal ascorbic acid content, the stress response of the mamillary body group was as marked as that of the operated control or the normal control group-immediately after termination of cold exposure. Recovery from the stress was accelerated significantly in the mamillary body group and insignificantly in the operated control group compared with that of the normal control group, the intergroup difference of the former two groups being insignificant. It was inferred from the above results that the mamillary bodies may exert an inconspicuous inhibitory influence upon the central mechanism of general activity, and that the mamillaryies bodies may not be the main seat of the stress mechanism, although more works are desirable to confirm the results.

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Consideration of Normal Variation of Perfusion Measurements in the Quantitative Analysis of Myocardial Perfusion SPECT: Usefulness in Assessment of Viable Myocardium (심근관류 SPECT의 정량적 분석에서 관류정량값 정상변이의 고려: 생존심근 평가에서의 유용성)

  • Paeng, Jin-Chul;Lim, Il-Han;Kim, Ki-Bong;Lee, Dong-Soo
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.4
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    • pp.285-291
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    • 2008
  • Purpose: Although automatic quantification software of myocardial perfusion SPECT provides highly objective and reproducible quantitative measurements, there is still some limitation in the direct use of quantitative measurements. In this study we derived parameters using normal variation of perfusion measurements, and tried to test the usefulness of these parameters. Materials and Methods: In order to calculate normal variation of perfusion measurements on myocardial perfusion SPECT, 55 patients (M:F = 28:27) of low-likelihood for coronary artery disease were enrolled and $^{201}TI$ rest/$^{99m}Tc$-MIBI stress SPECT studies were performed. Using 20-segment model, mean (m) and standard deviation (SD) of perfusion were calculated in each segment. As a myocardial viability assessment group, another 48 patients with known coronary artery disease, who underwent coronary artery bypass graft surgery (CABG) were enrolled. $^{201}TI$ rest/$^{99m}Tc$-MIBI stress / $^{201}TI$ 24-hr delayed SPECT was performed before CABG and SPECT was followed up 3 months after CABG. From the preoperative 24-hr delayed SPECT, $Q_{delay}$ (perfusion measurement), ${\Delta}_{delay}$ ($Q_{delay}$ - m) and $Z_{delay}$ (($Q_{delay}$ - m)/SD) were defined and diagnostic performances of them for myocardial viability were evaluated using area under curve (AUC) on receiver operating characteristic (ROC) curve analysis. Results: Segmental perfusion measurements showed considerable normal variations among segments. In men, the lowest segmental perfusion measurement was $51.8{\pm}6.5$ and the highest segmental perfusion was $87.0{\pm}5.9$, and they are $58.7{\pm}8.1$ and $87.3{\pm}6.0$, respectively in women. In the viability assessment $Q_{delay}$ showed AUC of 0.633, while those for ${\Delta}_{delay}$ and $Z_{delay}$ were 0.735 and 0.716, respectively. The AUCs of ${\Delta}_{delay}$ and $Z_{delay}$ were significantly higher than that of $Q_{delay}$ (p = 0.001 and 0.018, respectively). The diagnostic performance of ${\Delta}_{delay}$, which showed highest AUC, was 85% of sensitivity and 53% of specificity at the optimal cutoff of -24.7. Conclusion: On automatic quantification of myocardial perfusion SPECT, the normal variation of perfusion measurements were considerable among segments. In the viability assessment, the parameters considering normal variation showed better diagnostic performance than the direct perfusion measurement. This study suggests that consideration of normal variation is important in the analysis of measurements on quantitative myocardial perfusion SPECT.

Morphological Changes of Stomach Tissue on NPO(nil per os) of Rats Treated Single Irradiation (방사선 단일조사가 금식시킨 흰쥐 위에 미치는 형태학적 변화)

  • Kim, Boo-Soon
    • Journal of radiological science and technology
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    • v.21 no.1
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    • pp.69-78
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    • 1998
  • In this study, I examined the morphological influence of radiation on rats stomach tissue, the difference between NPO and CON(contrast) in the rats stomach was measured after a single irradiation to 15 Gy dose, the results follow; In histological observation; focal congestion and epithelial denudation were observed from NPO rats of a day after irradiation. Fibrosis was showed from both of NPO and CON rats of 28day after irradiation, but in it's area, NPO rats have been more wider than CON rats. In PAS reaction; secreted mucin was reacted very weakly from both of NPO and CON rats of 7 days and 14 days after irradiation, whereas CON rats of 28 days after irradiation were reacted like to control rats. On the basis of this results, we know obviously that NPO will be a factor of stomach abnomalities while hospital patients are treated with high-energy irradiation.

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Expression of nitric oxide synthase isoforms and N-methyl-D-aspartate receptor subunits according to transforming growth factor-β1 administration after hypoxic-ischemic brain injury in neonatal rats (신생 백서의 저산소 허혈 뇌손상에서 Transforming Growth Factor-β1 투여에 따른 Nitric Oxide Synthase 이성체와 N-methyl-D-aspartate 수용체 아단위의 발현)

  • Go, Hye Young;Seo, Eok Su;Kim, Woo Taek
    • Clinical and Experimental Pediatrics
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    • v.52 no.5
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    • pp.594-602
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    • 2009
  • Purpose : Transforming growth factor (TGF)-${\beta}1$ reportedly increases neuronal survival by inhibiting the induction of inducible nitric oxide synthase (NOS) in astrocytes and protecting neurons after excitotoxic injury. However, the neuroprotective mechanism of $TGF-{\beta}1$ on hypoxic-ischemic (HI) brain injury in neonatal rats is not clear. The aim of this study was to determine whether $TGF-{\beta}1$ has neuroprotective effects via a NO-mediated mechanism and N-methyl-D-aspartate (NMDA) receptor modulation on perinatal HI brain injury. Methods : Cortical cells were cultured using 19-day-pregnant Sprague-Dawley (SD) rats treated with $TGF-{\beta}1$ (1, 5, or 10 ng/mL) and incubated in a 1% O2 incubator for hypoxia. Seven-day-old SD rat pups were subjected to left carotid occlusion followed by 2 h of hypoxic exposure (7.5% $O_2$). $TGF-{\beta}1$ (0.5 ng/kg) was administered intracerebrally to the rats 30 min before HI brain injury. The expressions of NOS and NMDA receptors were measured. Results : In the in vitro model, the expressions of endothelial NOS (eNOS) and neuronal NOS (nNOS) increased in the hypoxic group and decreased in the 1 ng/mL $TGF-{\beta}1-treated$ group. In the in vivo model, the expression of inducible NOS (iNOS) decreased in the hypoxia group and increased in the $TGF-{\beta}1$-treated group. The expressions of eNOS and nNOS were reversed compared with the expression of iNOS. The expressions of all NMDA receptor subunits decreased in hypoxia group and increased in the $TGF-{\beta}1$-treated group except NR2C. Conclusion : The administration of $TGF-{\beta}1$ could significantly protect against perinatal HI brain injury via some parts of the NO-mediated or excitotoxic mechanism.

Effect of buchu (Allium tuberosum) on lipid peroxidation and antioxidative defense system in streptozotocin-induced diabetic rats (부추가 Streptozotocin 유발 당뇨쥐의 지질과산화와 항산화방어체계에 미치는 영향)

  • 송영선;정현실;노경희;조혜연;박지영;최춘연;권태완
    • Journal of Life Science
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    • v.13 no.3
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    • pp.333-342
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    • 2003
  • The pathogenic effort of high glucose, possibly in concert with fatty acids, is mediated to vascular complications of diabetes via increased production of reactive oxygen species(ROS), reactive nitrogen species(RNS), and subsequent oxidative stress. This study was carried out to investigate the suppressive effect of buchu(Allium tuberosum) on oxidative stress in streptozotocin(STZ)-induced diabetes in Sprague Dawley male rats. The effect of buchu supplementation (10%) on lipid peroxidation, and antioxidative defense system in blood and liver was compared among normal rats fed basal diet(normal) and diabetic rats fed basal diet(DM-control) or 10% buchu-supplemented diet(DM-buchu). Diabetes was experimentally induced by the femoral muscle injection of 50 mg STZ per kg of body weight. Animals were sacrificed after 4 wks of experimental diets feeding. The induction of diabetes by STZ elevated the level of lipid peroxidation represented by thiobarbituric acid-reactive substances(TBARS) and conjugated dienes in plasma, LDL, liver, and erythrocytes. 10% buchu-supplemented diet significantly reduced the levels of conjugated dienes in erythrocytes(p<0.05) and lowered TBARS in liver and LDL to the levels of control. Induction of diabetes by STZ elevated Mn-superoxide dismutase(Mn-SOD) activity and lowered activities of glutathionine reductase(GSH-red) and glutathionine peroxidase(GSH-px). Catalase activity was not affected by the induction of diabetes by STZ. However, buchu supplementation to diabetic rats significantly elevated catalase activity(p<0.05) and slightly elevated GSH-px and GSH-red activities in liver. GSH levels of blood and liver were lowered or not changed by induction of diabetes by STZ, respectively, while buchu supplementation to diabetic rats significantly elevated hepatic GSH level (p<0.05). In conclusion, it can be concluded that buchu might be a food source to attenuate oxidative stress in diabetic patients by inhibiting lipid peroxidation, by increasing hepatic GSH level, and by inducing anti-oxidative enzyme systems.

Analysis of Steady and Unsteady Flow Around a Ship Using a Higher-Order Boundary Element Method (고차경계요소법에 의한 선체주위 유동해석)

  • Sa-Y. Hong;Hang-S. Choi
    • Journal of the Society of Naval Architects of Korea
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    • v.32 no.1
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    • pp.42-57
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    • 1995
  • An efficient and accurate scheme has been constructed by taking advantages of the hi-quadratic spline scheme and the higher-order boundary element method selectively depending on computation domains. Boundary surfaces are represented by 8-node boundary elements to describe curved surfaces of a ship and its neighboring free surface more accurately. The variation of the velocity potential complies with the characteristics of the 8-node element on the body surface. But on the free surface, it is assumed to follow that of the hi-quadratic spline scheme. By which, the free surface solution is free from numerical damping and has better numerical dispersion property. As numerical examples, steady and unsteady Neumann-Kelvin problems are considered. Numerical results for a submerged spheroid, Series 60($C_B=0.6$) and a modified support the proposed method. Finally, a new upstream radiation condition is derived using a wave equation operator in order to deal with problems for subcritical reduced frequency. The relevance of this operator has been confirmed in the case of unsteady Kelvin source potential.

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Three-Dimensional Brain Surface Rendering Imaging of Cortical Dysplasia (뇌피질 이형성증의 3차원 뇌표면 연출영상)

  • Hwang, Seung-Bae;Kwak, Hyo-Sung;Lee, Sang-Yong;Jin, Gong-Yong;Han, Young-Min;Chung, Gyung-Ho
    • Investigative Magnetic Resonance Imaging
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    • v.14 no.2
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    • pp.126-133
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    • 2010
  • Purpose : The study was to evaluate the localization of the abnormal gyral and sulcal patterns obtained by means of brain surface rendering imaging. Materials and Methods : Nineteen patients with cortical dysplasia who underwent brain surface rendering MR imaging were included in this study. We acquired MP-RAGE sequence and created the 3-D surface rendering MR images by using $VoxelPlus^{(R)}$. Anatomical locations and configurations of abnormal gyri and sulci were reviewed. Results : Abnormal gyral and sulcal patterns were seen 18 in 19 patients. The configuration and orientation of affected gyri and sulci were clearly evaluated in the brain surface rendering images. In a lissencephaly, the a cortex was not delineated and showed markedly thick and smooth gyral pattern. In a schizencephaly, there were wheel shaped broad gyral pattern around the cleft. In a hemimegalencephaly, an affected hemisphere were enlarged and displayed thick and wide gyral pattern. In CBPS, the insular cortex was exposed and the gyri of the lesion were thickened. In focal cortical dysplasia, there were irregular serrated or thick and enlarged gyri. Conclusion : Brain surface rendering MR imaging is useful for the evaluation of a detailed gyral pattern and accurate involvement site of abnormal gyri.

A Cephalometric Study on factors affecting the FHI (Facial Height Index) in Angle's Class II division 1 malocclusion Patients (한국인 2급 1류 부정교합자의FHI(Facial Height Index)에 영향을 미치는 요소에 관한 두부방사선 계측학적 연구)

  • Park, Young-il;Lee, Jin-Woo;Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.26 no.4
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    • pp.401-413
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    • 1996
  • Facial vertical dyscrepancies is decided on the relationship between the anterior vertical facial height and posterior vertical facial height. Thus this study was conducted to determine the factors that affect the FHI, and classify the Class II div.1, malocclusion, which success is dependent on the vertical control according to the FHI, which is the ratio of antero-inferior facial height, posterio-inferior facial height ratio, and to use this as a guideline for treatment. Angle between palatal plane and Mandibular plane were in the order of RH, ID. Thus showing that interrelated angle was more inportant than the independent angle of both, palatal plane and Mandibular plane. The tendency of Cl II div.1. Malocclusion according to FHI, showed the Low group to have Mx. protrusion, prominent development of Mn. ramus, and the Mn. body length and ant. post. position was normal. The Normo group showed slight protrusion of the Maxilla,. The development of the ramus was less than normal and the Mn. was in a slight retruded position. The High group showed the Mx. in a normal position, the development of the Mn. ramus and body was the lowest, and the Mn. was in a posterior position. In observation of the factors affecting the FHI between each groups of Cl II div.l, malocclusion; In the Low group the MP- PP angle was very small, the ID was smililar to the normal group, but the RH was very large thus the FHI was increased. In the Normo group, the PP-MP angle was normal, ID was slightly smaller than the normal group and the RH was slightly smaller than the normal group, thus maintaining a normal FHI ratio. In the High group the PP-MP angle was very large, the ID was similar to the normal group, but the RH was smaller than the normal group thus the FHI was small.

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Dentoalveolar Compensation of Hyperdivergent Skeletal Pattern in Children and Adults (개방교합성 골격 형태를 가진 아동과 성인의 치성보상 양상)

  • Jeon, Young-Mi;Park, Dong-Cheol;Kim, Jong-Ghee
    • The korean journal of orthodontics
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    • v.29 no.2 s.73
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    • pp.197-207
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    • 1999
  • Although there is a severe underlying skeletal deformity, the dentition has often maintained some occlusal contact and interdigitation by the teeth compensating in their positions for the skeletal problem, and these dental compensations are manifested in all three planes of space. The purposes of present investigation were 1) to study the pattern of dentoalveolar compensation of hyperdivergent skeletal pattern , and 2) to compare the dentoalveolar compensations of hyperdivergent skeletal pattern in children with adults. The samples selected for this study were consisted of 60 subjects in normal group, 60 subjects in hyperdivergent group. Each was divided into two subgroups by age ; child groups($8\~12yr$ old) and adult groups(17yr old over). The findings of this study were as follows; 1. In child, hyperdivergent subjects had smaller posterior lower facial height(p<0.01) and slightly longer anterior lower facial height than normal ones. In adults, they still expressed smaller posterior lower facial height and much longer anterior lower facial height than normal ones(p<0.01). 2. Hyperdivergent subjects had larger amount of upper and lower incisor relative eruption to their basal bone length than normal ones(p<0.05). In adult, relative eruption of upper incisor was increasing(p<0.05), although relative eruption of lower incisor remained the same as the child. 3. In child, there was no difference between hyperdivergent group and nomal one in the upper and lower molar relative eruption to their basal bone length. In adult, hyperdivergent group had target amount of upper molar relative eruption than normal ones(p<0.01), but relative eruption of lower molar was similar to normal ones. 4. Hyperdivergent group had larger angle between lower occlusal plane and mandibular plane than normal group(p<0.01). Upper occlusal plane of adult groups rotated more antero-superiorly than child groups, and adult hyperdivergent group had sleeper upper occlusal plane than normal group(p<0.05).

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Increased Frequency of Sister Chromatid Exchanges After $^{131}I$ Therapy in Lymphocytes of Thyroid Cancer Patients (갑상선암 환자에서 방사성옥소($^{131}I$) 치료로 인한 림프구의 자매염색분체교환(SCE) 빈도증가)

  • Choi, Keun-Hee;Bom, Hee-Seung;Kim, Kwang-Yoon;Kim, Ji-Yeul;Yoon, Jung-Han;JaeGal, Young-Jong;Kim, Jae-Min
    • The Korean Journal of Nuclear Medicine
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    • v.27 no.1
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    • pp.118-122
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    • 1993
  • To evaluate the genotoxic effect of $^{131}I$, lymphocytes from 9 patients who underwent large dose (150 mCi) $^{131}I$ therapy after total thyroidectomy were studied for sister chromatid exchanges (SCE) before and after their first radioiodine treatments. Frequency of SCE (FSCE) was counted in chromosomes of 30 lymphocytes in each patients, and was expressed as numbers of SCE per cell. Numbers of leukocytes were also observed during $^{131}I$ therapy. Pretreatment FSCE ($4.2{\pm}0.7$) was not different from the control ($3.8{\pm}0.4$, p=0.17). However, the frequency was significantly elevated after $^{131}I$ administration (at the second day, $7.9{\pm}0.8$, p<0.001) and was diminished but still significantly elevated after a week (at 9th day, $6.4{\pm}0.6$, p<0.001). While counts of leukocytes in the peripheral blood showed no change (p> 0.05). In conclusion, chromatids of human lymphocytes were significantly damaged after $^{131}I$ treatment without any bone marrow supression. And the repair of SCE was not complete within one week.

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