• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.10
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• pp.494-501
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• 2001

In this study, the effects of vascular parameter changes and electrodes on VOP measurement based on IPG were simulated mathematically. For the evaluation of the effects of hemodynamic changes on VOP, a mathematical model, which consists of cardiovascular system model and venous occlusion model, was developed and the model solution representing the blood flow and pressure in measuring point was found by 2nd order Runge-Kutta method. And, with sensitivity coefficients obtained from finite element solution of electric field in measuring point, the effects of electrode system on measurement were evaluated. As increasing the resistance, the venous capacitance was not changed but the venous outflows were decreased and the decreased compliance reduced the venous capacitance. And, for several configurations of round electrodes and band electrodes, the sensitivity coefficients were computed using the electric field distribution along deep vein. In conclusion, the proposed mathematical cardiovascular model could be applied to the simulation study on the effects of hemodynamic parameters on DVT diagnosis with IPG. And, also the sensitivity coefficients could provide effective electrode configuration for exact measurement of VOP.

• The Korean Journal of Nuclear Medicine
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• v.6 no.1
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• pp.51-59
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• 1972

$^{86}Rb$ uptake of some organs and tissues, ego both lungs, both renal cortices. small intestine, liver and skeletal muscle were studied in the control and the rabbit subjected to pneumothorax. $^{86}Rb$ in the form of chloride mixed with physiological saline was intravenously. injected. The doses were $100{\mu}c$ for a rabbit. The rabbits were sacrificed at intervals of 10, 20, 40, and 60 seconds after the injection of $^{86}Rb$, by the injection of saturated KCI solution. After sacrification, the organ and tissue sample were quickly removed. $^{86}Rb$ uptake in gm of the organs and tissues were measured. On the basis of uptake value, administered doses and body weight, % dose/gm tissues per 200 gm body weight was calculated. Followings were the results; 1. Pneumothorax resulted in a marked elevation in $^{86}Rb$ uptake value of collapsed lung and returned to normal level lately. 2. Contralateral lung of pnemothorax also showed marked elevation in $^{86}Rb$ uptake value and recovered to normal level. 3. Initial $^{86}Rb$ uptake value of liver, small intestine of the rabbit with pneumothorax showed some elevation as compared to control, but that of late stage were similar with control. 4. Local blood flow determination by means of $^{86}Rb$ uptake were inadequate in the collapsed lung of pneumothorax. 5. It was suggested that the mechanism for the initial elevation of $^{86}Rb$ uptake value in each organs and tissue were different from each other.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1715-1720
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• 2013

Background: The discovery that microRNAs (miRNAs) regulate proliferation, invasion and metastasis provides a principal molecular basis of tumor heterogeneity. Microvessel distribution is an important characteristic of solid tumors, with significant hypoxia occurring in the center of tumors with low blood flow. The distribution of miR-374a in breast tumors was examined as a factor likely to be important in breast cancer progression. Methods: Breast tissue samples from 40 patients with breast cancer were classified into two groups: a highly invasive and metastatic group (HIMG) and a low-invasive and metastatic Group (LIMG). Samples were collected from the center and edge of each tumor. In each group, six specimens were examined by microRNA array, and the remaining 14 specimens were used for real-time RT-qPCR, Western blot and immunohistochemical analyses. Correlation analysis was performed for the miRNAs and target proteins. Follow-up was carried out during 28 months to 68 months after surgery, and survival data were analyzed. Results: In the LIMG, the relative content of miR-374a was lower in the center of the tumor than at its edge; in the HIMG, it was lower at the edge of the tumor, and miR-374a levels were lower in breast cancer tissues than in normal tissues. There was no difference between VEGF-A and VCAM-1 mRNA levels at the edge and center of the tumor; however, we observed a significant difference between VEGF-A and VCAM-1 protein expression levels in these two regions. There was a negative correlation between miR-374a and target protein levels. The microvessel density (MVD) was lower in the center of the tumor than at its edge in HIMG, but the LIMG vessels were uniformly distributed. There was a significant positive correlation between MVD and the number of lymph node metastases (Pearson correlation, r=0.912, P<0.01). The median follow-up time was 48.5 months. LIMG had higher rate of disease-free survival (100%, P=0.013) and longer median survival time (66 months) than HIMG, which had a lower rate of 75% and shorter median survival time (54 months). Conclusions: Our data demonstrated miR-374a to be differentially distributed in breast cancer; VEGF-A and VCAM-1 mRNA had coincident distribution, and the distribution of teh respective proteins was uneven and opposite to that for the miR-374a. These data might explain the differences in the distribution of MVD in breast cancer and variation in breast cancer prognosis.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.28-38
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• 2004

This study presents the result of uncertainty and sensitivity analysis of a pharmacokinetic model which describes the distribution and removal of benzene at each organ when an indivisual inhales indoor contaminated air with benzene originated from groundwater. The pharmacokinetic model simulates the distribution of benzene deposited in organs of human body through inhalation of contaminated indoor air as well as degradation-metabolism in liver. This study focused on the uncertainty problem induced from the use of the single values for blood flow, partition coefficient, degradation constant, volume, etc. of each organ which was due to a lack of knowledge about these parameters or their measurements. To solve this problem, uncertainty analysis on the pharmacokinetic model was conducted simultaneously which would help understanding the risk assessment associated with VOCs.

• Journal of Oriental Neuropsychiatry
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• v.11 no.2
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• pp.131-140
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• 2000

The clinical study was carried out the 41 patients with conversion disorder who were treated in Dae Jeon University Oriental Hospital from 26 september 1998 to 21 september 2000.The results were summarized as follows.1. The ratio of male and female was 4:37 and in the age distribution, the highest frequence was 40s, in descending order over 50s, 30s, 20s, 10s and mental attack was the most inducing factor.2. In distribution of the period of the clinical history. within one day was the highest percentage and in admission period most of the patients were from four days to seven days.3. In symptoms and signs, physical symptoms were more than mental symptoms, physical symptoms had many muscle-skeleton-system symptoms and they were in descending order general body weakness. headache, anorexia, chest discomfort, dyspepsia, dizziness, four extremities numbness, insomnia, dysarthria, anxiety, four extremities tremor. palpitation. nausea, vomiting, facial numbness.4. In classification of Four Human coporeal constitution the number of patients, Sho-Eum-In(少陰人) was remarked mostly and most of female patients had no past history of the conversion disorder.5. In distribution of the prescription, drugs of regulating gi such as BUNSIMGIEUM(分心氣飮) were many, in descending order drugs of growing heart and warming gall bladder such as ONDAMTANGGAMI(溫膽湯加味), drugs of maintaining patency for the flow of gi such as CHUNGGANSOYOSAN(淸肝逍遙散), drugs of decomposing food and asending gi such as PYUNGJINGUNBITANG(平陳健脾湯), drugs of storing blood and relaxing the mind such as SAMULGUIBITANG(四物歸脾湯). drugs of removing sputum and cooling heart such as CHUNGSIMDODAMTANG 淸心導痰湯).6. In distribution of the treatments, the group of drug and acupuncture and aroma-therapy was many, in acup uncture TAEGUKCHIMBUP(太極針法) was mainly used. in therapy inhalation type of Lavender and Rosewood was many and the type of Peppermint and Rosemary massaging epigastric-chest, and neck was many.7. In distribution of the treatment result, in 15 patients(36.6%) symptoms were eliminated from four to seven days, in 13 patients(31.7%) symptoms were not changed. in 12 patients(29.3%) symptoms were eliminated from two to three days. in 1 patients(2.4%) symptoms were eliminated whin one day.

• The Korean Journal of Nuclear Medicine
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• v.33 no.3
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• pp.247-261
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• 1999

Purpose: The aim of this study was to evaluate the normal values of regional cerebral blood flow (rCBF) and cerebrovascular reserve (CVR) in normal children to aged volunteers using Tc-99m HMPAO, Materials and Methods: Thirty four right-handed normal volunteers (20 males, 14 females, mean age $40.3{\pm}24.9$ years, range 4 to 82 years) were underwent rost/acetazolamide (ACZ) brain SPECT using Tc-99m HMPAO and the sequential injection and subtraction method. rCBF was estimated on the basis of a semiquantitative approach by means of right/left ratio, region/cerebellum and region to whole brain ratios in (rental, parietal, temporal, and occipital lobes, basal ganglia, thalami, and cerebellum. CVR was measured by means of % perfusion increase calculated as % mean count change compared to rest rCBF in each regions. Results: Mean values of right to left ratios range from 1.004 to 1.018, rCBF was highest in cerebellum and lowest in basal ganglia and thalami. Frontal and temporal rCBF decreased while occipital and thalamic rCBF increased according to age. No sexual difference of rCBF was noted. Mean CVR was $29.9{\pm}12.9%$. Mean CVR significantly increased to late teens, and declined thereafter. After 6th decade, CVR in both frontal lobes, left parietal lobe and right basal ganglia decreased significantly with advancing age. There was no sexual difference of CVR. Conclusion: Quantitative assessment of CVR was possible by ACZ Tc-99m HMPAO brain SPECT. It revealed that rCBF and CVR changed according to age in normal Korean volunteers. There was no sexual difference.

• Clinical and Experimental Pediatrics
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• v.51 no.12
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• pp.1336-1341
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• 2008

Purpose : This study aimed to determine the frequencies of $CD4^+CD25^+$ T cells in donor graft and peripheral blood $CD4^+CD25^+$ T cells in recipients after hematopoietic stem cell transplantation (HSCT) and their association with graft-versus-host disease (GVHD). Methods : Seventeen children who underwent HSCT were investigated. $CD4^+CD25^+$ T cells in samples from donor grafts and recipient peripheral blood were assessed by flow cytometry at 1 and 3 months after transplantation. Results : $CD4^+CD25^+$ T cell frequencies in the grafts showed no significant difference between patients with and without acute GVHD (0.90% vs. 1.06%, P=0.62). Absolute $CD4^+CD25^+$ T cell number in grafts were lower in patients with acute GVHD than in those without acute GVHD ($6.18{\times}10^5/kg$ vs. $25.85{\times}10^5/kg$, P=0.09). Patients without acute GVHD showed a significant decrease in peripheral blood $CD4^+CD25^+$ T cell percentage at 3 months compared to those at 1 month after HSCT (2.11% vs. 1.43%, P=0.028). However, in patients with acute GVHD, $CD4^+CD25^+$ T cell percentage at 3 months was not different from the corresponding percentage at 1 month after HSCT (2.47% vs. 2.30%, P=0.5). Conclusion : The effect of frequencies of $CD4^+CD25^+$ T cells in donor grafts on acute GVHD after HSCT could not be identified, and the majority of peripheral blood $CD4^+CD25^+$ T cells in patients who underwent HSCT may be activated T cells related to acute GVHD rather than regulatory T cells. Further studies with additional markers for regulatory T cells are needed to validate our results.

• Journal of Biomedical Engineering Research
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• v.16 no.2
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• pp.231-238
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• 1995

Tc-99m-MIBI (Sestamibi) myocardial SPECT along with TI-201 tomographic Imaging has demonstrated wide application and high image quality sufficient for the diagnosis of myocardial perfusion defect, which consequently reflects regional myocardial blood flow. The qualitative values of myocardial SPECT with Tc-99m-MIBI as well ds the quantitative cases depend in some degree on the reconstruction techniques of multiple projections. Filtered backprojection (FBP) Is the common standard method for reconstruction rather than the complicated and time-consuming arithmetic methods. In FBP it is known that the distribution of radioactivity in reconstructed transverse slices varies with the selected litter parameters such as cutoff frequencies and order (Butterworth case) The cutoff frequencies used in clinicAl practice partially remove and decrease the true radioactive distribution and alter the pixel counts, which lead to underestimation of true counts in specific myocardial regions. In this study, we have investigated the effect of cutoff frequencies of reconstruction filter on the artifactually induced perfusion defects, which are often demonstrated near inferior and/or inferoseptal cardiac walls due to the intense hepatic uptake of Tc-99m-MIBI. A computerized method for Identifying the relative degree of artifactual perfusion defect and for comparing those degrees along with the relative amount of hepatic uptake to myocardium was developed and patient images were studied to observe the quantitative degree of underestimation of myocardial perfusion, and to propose some reasonable threshold of cutoff frequency in the diagnosis of perfusion defect quantitatively. We concluded that from the quantitative viewpoint cutoff frequencies may be used as high as possible with the sacrifice of homogeneity of image quality, and those frequencies lower than the common 0.3 Wyquist frequency would reveal severe degradation of radioactive distribution near inferior and/or inferoseptal myocardium when applying Butterworth or low pass filter.

• Science of Emotion and Sensibility
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• v.14 no.3
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• pp.435-444
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• 2011

The development of ubiquitous healthcare technology and portable electronic devices requires new energy sources for providing continuous power supply. This study particularly focuses on an energy harvesting system capable of charging energy using clothing. One of the sources for energy harvesting is heat energy, which is the difference in temperature of the body and the surrounding environment. In this study, the skin temperature distribution of the human body was empirically measured to determine the basic materials needed to develop heat energy harvesting clothing. The distribution of skin temperature in different sections of the human body was analyzed. The analysis found that the skin temperature of the upper body was higher than that of the lower body. The area close to the heart with a lot of blood flow was especially high. The skin temperature of the back side of the body, such as the back of the neck, upper back, and waist, was higher than that of the front side of the body. As for the arms, the skin temperature of the upper arms was higher than that of the lower arms, and the skin temperature of the back side of the arms was lower than that of the front and the flank side of the arms. The difference in the average skin temperature and the environment temperature was highest at the back of the neck, and thereby is considered to be the most appropriate section to integrate the heat energy harvesting function and structure. The following sections had the next highest difference in values, listed in descending order: the back of the waist, the sides of shoulders, the front chest area, the front side of the upper arms, and the front abdomen. Based on the skin temperatures of the different sections of the human body, this study outlines the basic guidelines for developing heat energy harvesting clothing.

• Journal of Pharmacopuncture
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• v.8 no.3
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• pp.5-9
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• 2005

Observation of intra-vascular threadlike structures in the blood vessels of rats is reported with the images by differential interference contrast microscope, and fluorescence inverted microscope of the acridine-orange stained samples. The confocal microscope image and the hematoxylin-eosin staining revealed the distinctive pattern of nuclei distribution that clearly discerned the threadlike structure from fibrin, capillary, small venule, arteriole, or lymph vessel. Physiological function of the intra-vascular thread in connection with acupuncture is discussed. Especially, this threadlike duct can be a circulation path for herb-liquid flow, which may provide the scientific mechanism for therapeutic effect of herbal acupuncture.