• 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.

• Journal of the Korean Electrochemical Society
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• 제10권1호
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• pp.7-13
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• 2007

We synthesized and investigated $La_{0.75}Sr_{0.25}FeO_3$ by Glycine Nitrate Process(GNP) method used as cathode materials for SOFC(solid oxide fuel cell). Optimized amount of glycine is 3.17 mol. ICP elemental composition analysis indicated that the stoichiometry of the synthesized powders have nearly nominal values. SEM images and XRD patterns reveal that the synthesized powder has uniform size distribution and high degree of crystallinity. The sample powders were isostatically pressed to form a pellet. The green body was sintered at $1200^{\circ}C$ and the relative density of the sintered specimens were measured by Archimedes mettled. We measured electrochemical performance of LSF by AC impedance spectroscopy. Resistance of LSF shows lower value than that of LSM throughout all temperature region. The anode-supported solid oxide fuel cell showed a performance of $342mW/cm^2(0.7V,\;488mA/cm^2)$ at $750^{\circ}C$. The electrochemical characteristics of the single cell were examined by at impedance method.

• Trans-
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• 제2권
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• pp.161-190
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• 2017

As times progress, creative change is achieved by attempts to embrace different needs. These attempts are expressed as the form of an Object which pulls down the barriers of genre between art. There is now in fact difficult to find a work that doesn't contain the characteristic of an Object. The necessity of this study is that it tries to approach an Object with a holistic perspective and understand it as a single system. It also tries to analyze the roles that an Object's characteristic and expression and the research ways they influence the dance work by contemplating the aesthetic discussion process of an Object in the art field. Also, by researching the characteristics of expression and how Objects stimulate a dance work, this study will take an important part in developing the dance works. Based on this necessity, this research choose the works of William Forsythe, (2006), (2009), (2009) which clearly depicts the expression characteristics of an Object. It is noted that the usage of an Object maximized creativity and brought expansion of expressions in a dance performance by using diverse mediums, body actions and even nonmaterial components without losing the essence of a dance. As a result, this usage of an Object provides theories that bring the enlargement of expression and suggests various ways to overcome the limits of other existing dance works.

• Journal of Ginseng Research
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• 제28권1호
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• pp.5-10
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• 2004

This study was carried out to investigate the effect of the active ingredients from ginseng on paraquat(PQ) toxicity. Oxidative stress was induced by intraperitreatneal injection of PQ at a single dose of 25 mg/kg. Saponin treated groups were given protopanaxadiol saponins(PPD) or protopanaxatriol saponins(PPT)(5 mg/kg, orally) per day for 1, 3, & 7 days. We also investigated the relationship between lipid peroxidation and ginseng saponins by measuring the levels of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase (GPx), reduced glutathione(GSH), malondialdehyde (MDA), and hydrogen peroxide(H$_2$O$_2$) in liver tissue. The activities of SOD, CAT, and GPx were generally high in the PPD group; the SOD activity on each day was the highest in the PPD group. The H$_2$O$_2$ content was the lowest in the PPD group. The GSH levels were significantly increased in the PPD. The levels of MDA(the end product of lipid peroxidation) were significantly lower in the red ginseng component groups than in the PQ group; the levels were especially low in the PPD groups. These results led us to conclude that the antioxidant effects of extracts from red ginseng prevent oxidative damage by direct antioxidant effects involving SOD, CAT, & GPx, and increasing the ability of the body to synthesize endogenous antioxidants.

• The Research Journal of the Costume Culture
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• 제18권2호
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• pp.261-276
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• 2010

The analysis of an art trend in the principle dimension starts by observing the object of work in the perspective of formative composition and recognizing it as a universal system. It can be said that it is consistent with an interpretation method for a form theory of formal history by Heinrich W$\ddot{o}$lfflin, a leading form critic in art criticism. Hence, the purpose of this study was to find out what are the formative principles in Renaissance Classicism as a design principle to be applicable to modern fashion by reviewing the formative characteristics of Renaissance Classicism Architecture with which W$\ddot{o}$lfflin directly dealt. As for the theoretical literature review, I used W$\ddot{o}$lfflin's theoretical framework and looked at the Renaissance Classicism Architecture that he studied and examined the possibility of utilizing his theory as a layout principle and the characteristics. As for analysis of design cases, I applied the aforementioned architecture layout principle to modern fashion and conducted case study analysis to delve into distinctive layout principles found in fashion. The study showed that the Renaissance Classicism Architectural Style is marked by linearity, planarity, closing and multiple unity: linearity was expressed in the observation form in fixed frontal view and an emphasis on a tangible silhouette homeogenous and definite line structures; planarity was achieved in the form of paralleled layers of frontal view element, planarity style, and identical and proportional repetition of various sizes.; closing signified the pursuit of complete and clear regularity, and architecture developed in a constructive phase through organizational inevitability and absolute invariability.; multiple unity was expressed in self-completedness and independent parallel of discrete forms and harmony of emphasized individual elements in a totality. Applying these layout characteristics of the Renaissance Classicism Architectural style and to see their individual expressive features, I found out that in adopting layout principles of the Renaissance Classicism Architecture to modern fashion, it turned out to be an emphasis of individual silhouettes, a flattened space, completed objects, organic harmony among independent parts: the emphasis of individual silhouettes was expressed in individual definitiveness of formative lines of clothes in accordance with body joints and an emphasis on formative lines of clothes; the flattened space was marked by single layer structure, planarity of elements of clothes, and listing arrangement by appropriate proportion.; the completedness of the objects was expressed by the stationary state where overall image is fixed, the construction of homogeneous and complete space, and absolute inevitability of internal layout in proportion; lastly, organic harmony of independent parts was stressed in independent completedness of each detail, and organic harmony of the whole. The expressive features would lead to a unique expression style of linear emphasis, proportion, constructive forms, and two-dimensional arrangement. The meaning of this study is follows: The characteristics of art school of thought are given shape by appling & analysing the architectural layout principles of historical art school of thought to modern fashion in the view point of formal construction dimension. The applied possibility of historical art school of thought as the source of inspiration about the fashion design is extended.

• Clean Technology
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• 제17권3호
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• pp.273-279
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• 2011

The physicochemical properties of manufactured nanomaterials can vary depending upon the methods of manufacture, although the utilized raw materials are same. Hence, the toxicity can also vary based on the methods of nanomaterials manufacture. In this study, we compared the toxicity effect of two types of CNTs (MWCNT, multi-walled carbon nanotube; SWCNT, single-walled carbon nanotube) that differ in length and wall number. In case of MWCNTs, inflammatory responses were more strongly induced in longer groups, whereas body weights more clearly decreased in shorter groups. SWCNT significantly decreased the relative weights of brain and kidney, and the inflow of immune cells and the hematological changes were observed significantly on day 1 and day 7 after exposure, respectively. Our results showed that the length and wall number of CNTs can serve as critical factors in the exhibited inflammation and toxicity.

• The Journal of Korean Obstetrics and Gynecology
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• 제20권1호
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• pp.99-113
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• 2007

Purpose : This study was designed to investigate the effects of Jeongkyeong-Tang(JKT) on the polycystic ovary(PCO) induced by estradiol valerate(EV) in rats. Methods : PCO was induced by single intramuscular injection with EV(4mg) in female rats. Normal group(n=8) were injected with sesame oil and orally administrated distilled water for sixty days. PCO control group(n=8) were injected with EV and orally administrated distilled water for sixty days. JKT treated group(n=8) were injected with EV and orally administrated JKT for sixty days. Then we measured weights of body, ovaries and adrenal glands, and measured content of serum estrogen. The histomorphometrical changes of ovaries were also evaluated. The expressions of nerve growth factor(NGF) were analyzed in the central nervous system, adrenal glands and ovaries by immunohistochemistry. Results : - The weights(mg) of ovaries in JKT treated group (69.7${\pm}$6.7) were significantly increased( p<0.001) compared with PCO control group(46.7${\pm}$12.2). - The numbers of secondary follicles in JKT treated group(4.00${\pm}$l.31) were significantly increased(p <0.05) compared with PCO control group(2.25${\pm}$1.39). - The numbers of mature follicles in JKT treated group(5.50${\pm}$1.51) were significantly increased(p<0.01) compared with PCO control group(2.88${\pm}$1.13). - The numbers of atretic follicles in JKT treated group(2.75${\pm}$l.16) were significantly decreased(p<0.001) compared with PCO control group(6.88${\pm}$2.03). - The numbers of corpora lutea in JKT treated group(4.13${\pm}$1.46) were significantly increased(p<0.01) compared with PCO control group(2.13${\pm}$1.46). - The contents(pg/ml) of serum estrogen in JKT treated group(115.18${\pm}$18.29) were significantly decreased(P<0.01) compared with PCO control group(153.06${\pm}$29.47). - The expressions of NGF-immunoreactive cells in the ovarian granulosa cells in JKT treated group were lesser observed than PCO control group. Conclusion : From the above results, we concluded that Jeongkyeong-Tang has inhibitory effect on the development of EV-induced polycystic ovary. And it's effect may be related with decreased NGF activities in the ovary.

• Journal of Veterinary Clinics
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• 제29권2호
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• pp.130-133
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• 2012

The purpose of this study is to assess the relationship between glomerular filtration rate (GFR) and age by using dynamic computed tomography (CT) and Patlak plot analysis in dogs. Fifteen dogs were used in this study. CT-GFR study was performed under general anesthesia using propofol and isoflurane. 1 ml/kg dosage of 300 mgI/ml iohexol was administered at a rate of 3 ml/s during GFR measurement. CT-GFR was determined with a single-slice dynamic acquisition and Patlak plot analysis. The individual and global GFR values were calculated to plasma clearance per body weight (ml/min/kg). Bodyweight ($mean{\pm}SD$) ranged from 2.0 to 5.7 kg ($3.31{\pm}1.13$ kg). Age ranged from 3 years to 13 years old ($7.14{\pm}3.30$). $Mean{\pm}SD$ creatinine ($0.53{\pm}0.34 $mg/dl), phosphorus ($4.1{\pm}1.2$ mg/dL), and albumin ($3.3{\pm}0.3$ mg/dL) concentrations and urine protein-to-creatinine ratios (all ratios were < 0.5) were within reference ranges. Abdominal ultrasonography revealed small-sized renal calculi, mineralization, or renal cyst at eight dogs. The global CT-GFR ranges shown in this study was 2.57 to 6.60 ml/min/kg. In this study, there was no trend toward weight-adjusted CT-GFR with increasing age. We found no relationships between age-related kidney dysfunction in fifteen dogs. Small-sized renal calculi or cysts did not affect renal function in this study. However, it is thought that a large sample size may have been required to document an age effect.

• Journal of Pharmaceutical Investigation
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• 제38권6호
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• pp.413-419
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• 2008

Carvedilol, is a nonselective $\beta$-blocking agent and it also has vasodilating properties that are attributed mainly to its blocking activity at ${\alpha}_1$-receptors. The purpose of the present study was to evaluate the bioequivalence of two carvedilol tablets, $Dilatrend^{(R)}$ tablet 12.5 mg (Chong Kun Dang Pharmaceutical Co., Ltd.) and Cadilan tablet 12.5 mg (KyungDong Pharmaceutical. Co., Ltd.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of carvedilol from the two carvedilol formulations in vitro was tested using KP VIII Apparatus II method with pH 4.5 dissolution medium. Thirty two healthy male subjects, $25.00{\pm}3.09$ years in age and $70.71{\pm}11.35\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After a single tablet containing 12.5 mg as carvedilol was orally administered, blood samples were taken at predetermined time intervals and the concentrations of carvedilol in serum were determined using HPLC with fluorescence detector. The dissolution profiles of two formulations were similar in the tested dissolution medium. The pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, $Dilatrend^{(R)}$ tablet 12.5 mg, were 4.66%, 8.33% and -7.45% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 (e.g., $\log\;0.9823{\sim}\log\;1.1042$ and $\log\;1.0132{\sim}\log\;1.1875$ for $AUC_t$ and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Cadilan tablet 12.5 mg was bioequivalent to $Dilatrend^{(R)}$ tablet 12.5 mg.

• The Korean Journal of Pesticide Science
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• 제15권4호
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• pp.507-528
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• 2011

Agricultural workers who mix/loads and spray pesticide in fields expose to pesticide through dermal and inhalation routes. In such situation, exposed amount should be measured quantitatively for reasonable risk assessment. Patch, gloves, socks and mask will be good materials for monitoring for dermal exposure while personal air monitor equipped with solid adsorbent and air pump will be a tool for inhalation exposure. For extrapolation of absorbed amount in dermal exposure matrices and of trapped amount in solid sorbent to total deraml or inhalation exposure, Korean standard body surface area and respiration rate were proposed in substitution of EPA data. Important exposure factors such as clothing and skin penetration ratio of dermal and inhalation exposure were suggested based on Spraying time for exposure monitoring must be long enough that the amount of pesticide to get absorbed/trapped in exposure matrices results in reasonable analytical value. In domestic case for the both of speed sprayer and power spray machine, spraying time of 20~40 minutes (0.1~0.2 ha) will be reasonable per single replicate before extrapolating to 4 hours a day with triplicates experiment.