• Journal of the Korean Society of Radiology
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• v.10 no.8
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• pp.619-627
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• 2016

The purpose of this study is to investigate the effect of CT contrast agent and MRI contrast agent on the area dose in the body when using automatic exposure control system in general radiography. After making rectangular holes in the center of the abdominal thickness paraffin phantom, CT contrast agent and MRI contrast agent were respectively diluted with physiological saline solution for contrast medium dilution ratio of 10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:10%. Each experiment was set to 78 kVp, 320 mA, which is the proper condition for KUB photography, and thereafter a total of 30 inspections were made for each dilution ratio using an automatic exposure control device, and the area dose corresponding to the dilution ratio of each contrast agent, Average comparison and correlation analysis were performed on the exposure index. As a result, the CT contrast agent and the MRI contrast agent appeared different in area dose according to the dilution ratio(p<0.05), and as the dilution ratio increased, the area dose increased for CT contrast agent and MRI contrast agent(P<0.05). In each test, the exposure index showed the manufacturer's recommendation of 200-800 EI value, and the exposure index and area dose increased as the area dose increased(p<0.05). In conclusion, CT contrast agent and MRI contrast agent confirmed to increase the area dose by general imaging test using all automatic exposure control device. Therefore, it is considered that it is necessary to perform it after the contrast medium has been excreted sufficiently when using usual imaging test after using the contrast agent in CT and MRI examination.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.3
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• pp.169-176
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• 2006

Purpose: According to the development of CT scanner in PET/CT system, the role of CT unit as a diagnostic tool has been more important. To improve the diagnostic ability of CT scanner, it is a key aspect that CT scanning has to be performed with high dose energy and intravenous (IV) contrast. So we investigated the effect of IV contrast media on the maximum SUV (maxSUV) of normal tissues and pathologic lesions using PET/CT scanner with high dose CT scanning. Materials & Methods: The study enrolled 13 patients who required PET/CT evaluation. At first, the patients were performed whole body non-contrast CT (NCCT-120 kVp, 130 mAs) scan. Then contrast enhanced CT (CECT) scan was performed immediately. Finally PET scan was followed. The PET omission data were reconstructed twice, once with the NCCT and again with the CECT. We measured the maxSUV of 10 different body regions that were considered as normal in ail patients. Also pathologic lesions were investigated. Results: There were not seen focal artifacts in PET images based on CT with IV contrast agent. Firstly, 130 normal regions in 13 patients were evaluated. The maxSUV was significantly different between two PET images (p<0.00)). The maxSUV was $1.1{\pm}0.5$ in PET images with CECT-corrected attenuation and $1.0{\pm}0.5$ in PET images with NCCI-corrected attenuation. The limit of agreement was $0.1{\pm}0.3$ in Bland-Altman analysis. Especially there were significant differences in 6 of 10 regions, apex and base of the right lung, ascending aorta, segment 6 & segment 8 of the liver and spleen (p<0.05). Secondly, 39 pathologic lesions were evaluated. The maxSUV was significantly different between two PET images (p<0.001). The maxSUV was $4.7{\pm}2.0$ in PET images with CECT-corrected attenuation and $4.4{\pm}2.0$ in PET images with NCCT-corrected attenuation. The limit of agreement was $0.4{\pm}0.8$ in Bland-Altman analysis. Conclusion: Although there were increases of maxSUVs in the PET images based on CT with IV contrast agent, it was very narrow in the range of limit of agreement. So there was no significant effect to clinical interpretation for PET images that were corrected attenuation with high dose CT using IV contrast.

• Journal of Pharmacopuncture
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• v.10 no.1 s.22
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• pp.85-100
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• 2007

Objectives : This research was executed to verify antitumor effect and protective effect on doxorubicin(Doxo)-induced toxicity of Cultivated Wild Ginseng(CWG) and synergic effect of CWG with Doxo in B16/F10 melanomas-bearing C57BL/6 mice. Methods : To evaluate protective effect on doxorubicin(Doxo)-induced toxicity and enhancing effect on the antitumor activity of Doxo, CWG water extract(0.5 ml) was intraperitoneally injected for 10 days, in combination with intraperitoneal injection of Doxo(4 mg/kg) on days 12, 16, 19, to mice subcutaneously inoculated with $2{\times}10^6/ml$ B16/F10 melanoma cells. In order to investigate antitumor effect of CWG, CWG water extract(0.5 ml) was intraperitoneally injected for 10 days to mice subcutaneously inoculated with $2{\times}10^6/ml$ B16/F10 melanoma cells. Results : The body weights of melanoma-bearing mice increased following B16/F10 cells inoculation. In contrast, such an increase in body weights was significantly attenuated by Doxo administration. Whereas CWG inhibits the decrease in body weights induced by Doxo. The tumor volume and tumor weights of melanomas-bearing mice dramatically increased following B16/F10 cells inoculation, In contrast, such an increase in tumor volume and tumor weights were significantly attenuated by Doxo or CWG administration. But the synergic effect of CWG with Doxo was not observed. The reduction of cellularity of seminiferous epithelia, level of spermatogonium and spermatid induced by Doxo was recovered by CWG administration. BrdU labeling index of spermatogonium was remarkably decreased in Doxo group but was no change in CWG group. Whereas the incidence and intensity of BrdU labelled spermatocytes and spermatids were increased by CWG administration than those of Doxo group. Conclusions : The obtained results suggest that CWG have antitumor effect and protective effect on doxo-induced testicular toxicity. This effect might be mediated through the supplementation of vital energy.

• The Journal of Korean Academy of Prosthodontics
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• v.17 no.1
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• pp.47-59
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• 1979

In order to study the morphologic changes of the unfixed odontoblasts suspended in phenol solution of several different concentrations, the author carried out the extraction of lower incisor of S-D strain rats to collect the odontoblasts, and the cells obtained were suspended immediately in saline solution. After observing the odontoblasts in fresh state, the saline solution was substituted with 0.125%, 0.25% 0.5%, 1% and 2% diluted phenol solutions. The morphologic changes were examined with phase contrast microscope at intervals of 10, 30, and 60 minutes. The results were as follows: 1. In saline solution the odontoblast showed cytoplasmic swelling, slender cytoplasmic process, thick rim nuclear membrane with increased dark contrast, and prominent nucleoli and chromatin granules with lapse of time intervals. In accordance with time intervals, blisters appeared in the supranuclear zone and increased its size and moved outward of the cytoplasmic membrane resulting detachment from the cell membrane. The phase dark cytoplasmic granules were increased in its dark contrast and in its size. 2. In 0.125% and 0.25% phenol solution, the odontoblasts and its nucleus shrunk immeidately and its contrast of cellular components was increased. With the lapse of time, the phase-dark granules in cytoplasm were aggregated, and several blisters were formed in and out of the cells. The outline of cytoplasmic membrane was also obscured. 3. In 0.5% phenol solution, the necleus shrunk at once, but soon after it revealed karyolysis accompanying dark contrast of neclear components such as nuclear membrane, nucleoli, and chromatin granules. On the contrary, the cytoplasmic granules showed aggregation and increased dark contrast, small and large blisters were formed in and out of the odontblasts and the outline of cytoplasmic membrane became obscured. 4. In 1% phenol solution, it showed shrinkage of odontblasts and its nuclei with thick rim nuclear membrane, aggregation of chromatin granules and occasional karyorrhexis. The dark contrast of cytoplasmic granules was increased and aggregated each other. But the blister formation could not be found. 5. In 2% phenol solution, it showed the shrinkage of odontoblasts and pyknotic nuclei with increased dark contrast of nucleoli and chromatin granules. The number of cytoplasmic granules was decreased by aggregation. But the blister formation could not be found as in 1% phenol solution.

• Journal of radiological science and technology
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• v.40 no.1
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• pp.71-78
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• 2017

Scattered radiation is inherent phenomenon of x-ray, which occurs to the subject (or patient). Therefore it cannot be avoidable but also interacts as serious noise factor because the only meaningful information on x-ray radiography is primary x-ray photons. The purpose of this study was to quantify scattered radiation for various shooting parameters and to verify the effect of anti-scatter grid. We employed beam stopper method to characterize scatter to primary ratio. To evaluate effect on the projection images calculated contrast to noise ratio of given shooting parameters. From the experiments, we identified the scattered radiation increases in thicker patient and smaller air gap. Moreover, scattered radiation degraded contrast to noise ratio of the projection images. We find out that the anti-scatter grid rejected scattered radiation effectively, however there were not fewer than 100% of scatter to primary ratio in some shooting parameters. The results demonstrate that the scattered radiation was serious problem of medical x-ray system, we confirmed that the scattered radiation was not considerable factor of dig ital radiog raphy.

• Journal of the Korean Society of Radiology
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• v.11 no.5
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• pp.329-334
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• 2017

The purpose of this study is to estimating the possibility of manufacturing radiation shielding sheet by searching for environmentally friendly materials suitable for medical environment of medical radiation shielding. There are many tungsten products which are currently used as shielding materials in place of lead, but there are small problems in the mass production of lightweight shielding sheets due to economical efficiency. To solve these problems, a lightweight, environmentally friendly material with economical efficiency is required. In this study, Barium sulphate and Iodine were proposed. Both materials are already used as contrast medias in radiography, and it is predicted that the shielding effect will be sufficient in a certain region as a shielding material because of the characteristic of absorbing radiation. Therefore, in this study, we used a Monte Carlo simulation to simulate radiation shielding materials. When it is a contrast agent such as Barium sulfate and Iodine, the radiation absorption effect in the high energy region appears greatly, and the effectiveness of the two shielding substance in the energy region of the star with thickness of 120 kVp is also evaluated in the medical radiation imaging region. Simulated estimation results it was possible to estimate the effectiveness of shielding for all two substances. Iodine has higher shielding effect than barium sulfate, 0.05 mm thick appears great effect. Therefore, the Monte Carlo simulation confirms that iodine, which is a radiological contrast agent, is also usable as barium sulfate in the production of radiation shielding sheets.

• The Korean Journal of Pain
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• v.22 no.2
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• pp.151-157
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• 2009

Background: We hypothesized that if a fluoroscopic image of the lumbar sympathetic ganglion block (LSGB) showed the spread patterns of contrast at both the L2/3 and L4/5 disc areas, then this would demonstrate a more profound blockade effect because the spread patterns are close to sympathetic ganglia. In addition, we compared the effects of LSGB and transforaminal epidural steroid injection (TFESI) for the patients suffering with spinal stenosis. Methods: Eighty patients were divided into two groups (Group S: the patients treated with TFESI, Group L: the patients treated with LSGB). The patients of group L were classified into three groups (groups A, B and, C) according to their contrast spread pattern. The preblock and postblock temperature difference between the ipsilateral and contralateral great toe ($DT^{pre}$, $DT^{post}$, $^{\circ}C$), and the DTnet were calculated as follows. $DT^{net}$ = $DT^{post}$ - $DT^{pre}$. Results: Both group showed a significant reduction of the visual analogue score (VAS) and the Oswestry disability index (ODI) score. Only the patients of group L showed a significant increase of their walking distance (WD). Group A showed the most significant changes in the $DT^{post}$ ($6.1{\pm}1.2^{\circ}C$, P = 0.021), and the DTnet ($6.0{\pm}1.0^{\circ}C$, p = 0.023), as compared to group C. Conclusions: LSGB showed a similar effect on the VAS, and ODI, and a significant effect, on WD, compared with TFESI. Group A showed a significant sympatholytic effect, as compared to group C.

• Phonetics and Speech Sciences
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• v.2 no.1
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• pp.41-50
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• 2010

The current study exploresacoustic variation induced by prosodic contexts in different speech styles,with a focus on motherese or child-directed speech (CDS). The patterns of variation in the acoustic expression of voicing contrast in English stops, and the role of prosodic factors in governing such variation are investigated in CDS. Prosody-induced acoustic strengthening reported from adult-directed speech (ADS)is examined in the speech data directed to infants at the one-word stage. The target consonants are collected from Utterance-initial and -medial positions, with or without focal accent. Overall, CDS shows that the prosodic prominence of constituents under focal accent conditions variesin the acoustic correlates of the stop laryngeal contrasts. The initial position is not found with enhanced acoustic values in the current study, which is similar to the finding from ADS (Choi, 2006 Cole et al, 2007). Individualized statistical results, however, indicate that the effect of accent on acoustic measures is not very robust, compared to the effect of accent in ADS. Enhanced distinctiveness under focal accent is observed from the limited subjects' acoustic measures in CDS. The results indicate dissimilar strategies to mark prosodic structures in different speech styles as well as the consistent prosodic effect across speech styles. The stylistic variation is discussed in relation to the listener under linguistic development in CDS.

• Journal of Fashion Business
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• v.12 no.1
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• pp.30-44
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• 2008

The purpose of this study is to investigate the effect of eyeshadow color(brown, purple), lipstick color(red, red purple, and yellow red), and lipstick tone(vivid, light, dull, and dark), clothing tone(vivid, light, dull, and dark) on image formation. Sets of stimulus and response scales(7 point semantic) were used as experimental materials. The stimuli were 64 color pictures manipulated with the combination of eyeshadow color, lipstick color, lipstick tone, and clothing tone using computer simulation. The subjects were 384 female undergraduates living in Gyeongnam-do. Image factor of the stimulus was composed of 4 different components (attractiveness, visibility, gracefulness, and tenderness). In the 4 image components, eyeshadow color and clothing tone showed independent effect. Lipstick tone influenced independently on the visibility and tenderness. In the contrast color coordination of clothing and makeup, visibility image by the coordination of lipstick color with lipstick tone, lipstick color with clothing tone or lipstick tone with clothing tone, gracefulness image by the coordination of eyeshadow color with lipstick color, tenderness image can be produced by the coordination of eyeshadow color with lipstick color, eyeshadow color with lipstick tone or eyeshadow color with clothing tone.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.337-345
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• 2014

The purpose of this study is to evaluate exposure dose and absorbability according to differences in the content of iodine in contrast media used in interventional procedure and angiography. There were 7 levels of iodine content as 240, 270, 300, 320, 350, 370, and 400 I $mg/m{\ell}$. The higher iodine content was, the more elevated exposure dose and absorbability were. The output dose was about 8.5% from iodine content with 350I $mg/m{\ell}$ higher than that with 270 I $mg/m{\ell}$ in TACE. These results mean that contrast media can have an effect on patient's exposure dose and high iodine content contrast media results in elevation of patient's exposure dose.