• Investigative Magnetic Resonance Imaging
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• v.13 no.1
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• pp.31-39
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• 2009

Purpose : This study proposes the keyhole method in order to improve the time resolution of the proton resonance frequency(PRF) MR temperature monitoring technique. The values of Root Mean Square (RMS) error of measured temperature value and Signal-to-Noise Ratio(SNR) obtained from the keyhole and full phase encoded temperature images were compared. Materials and Methods : The PRF method combined with GRE sequence was used to get MR temperature images using a clinical 1.5T MR scanner. It was conducted on the tissue-mimic 2% agarose gel phantom and swine's hock tissue. A MR compatible coaxial slot antenna driven by microwave power generator at 2.45GHz was used to heat the object in the magnetic bore for 5 minutes followed by a sequential acquisition of MR raw data during 10 minutes of cooling period. The acquired raw data were transferred to PC after then the keyhole images were reconstructed by taking the central part of K-space data with 128, 64, 32 and 16 phase encoding lines while the remaining peripheral parts were taken from the 1st reference raw data. The RMS errors were compared with the 256 full encoded self-reference temperature image while the SNR values were compared with the zero filling images. Results : As phase encoding number at the center part on the keyhole temperature images decreased to 128, 64, 32 and 16, the RMS errors of the measured temperature increased to 0.538, 0.712, 0.768 and 0.845$^{\circ}C$, meanwhile SNR values were maintained as the phase encoding number of keyhole part is reduced. Conclusion : This study shows that the keyhole technique is successfully applied to temperature monitoring procedure to increases the temporal resolution by standardizing the matrix size, thus maintained the SNR values. In future, it is expected to implement the MR real time thermal imaging using keyhole method which is able to reduce the scan time with minimal thermal variations.

• Journal of Biomedical Engineering Research
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• v.42 no.3
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• pp.86-93
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• 2021

Purpose: The purpose of this study is to find out the cognizance of medical device safety information (MDSI) monitoring in the hospital and oriental hospital workers, and the different aspect of MDSI between oriental medical devices and medical devices. Methods: The survey was performed both in the oriental medicine hospital and general hospital. The survey had 16 items; 2 items basic questions, 5 items in the awareness of MDSI, 5 items in the education of MDSI, 4 items in the necessity of defining oriental medical devices and differences between general and oriental medical devices. A total of 120 hospital worker were participated; 60 oriental medicine hospital workers and 60 general hospital workers. They had worked in the oriental medicine or general hospital associated with 'Medical Device Safety Monitoring Center, Dongguk University Ilsan Hospital' in 2019 and 2020. Results: The cognizance of MDSI was high both in oriental medicine hospital and general hospital workers and there were no significant differences between oriental medicine and general hospital workers. When we divided the hospital workers into the senior workers who had worked for over 3 years and junior workers for less than 3 years, the senior workers had higher awareness of MDSI than junior workers. However, the cognizance of education of MDSI was high which was not different between senior and junior workers. Both hospital workers thought that it was necessary to define oriental medicine device legally and the oriental medical device might have low risk and less side effect than medical device. Conclusion: The cognizance of MDSI was high and there was no significant differences between oriental medicine and general hospital workers. Because the senior hospital workers had higher recognition of MDSI, we need to provide the continuous education program for junior hospital workers. Although oriental medical device are thought to be safer than medical device, we need to have a legal definition.

• Journal of Chest Surgery
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• v.52 no.6
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• pp.392-399
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• 2019

Background: The surgical strategies for carotid endarterectomy (CEA) vary in terms of the anesthesia method, neurological monitoring, shunt usage, and closure technique, and no gold-standard procedure has been established yet. We aimed to analyze the feasibility and benefits of CEA under regional anesthesia (RA) and CEA under general anesthesia (GA). Methods: Between June 2012 and December 2017, 65 patients who had undergone CEA were enrolled, and their medical records were prospectively collected and retrospectively reviewed. A total of 35 patients underwent CEA under RA with cervical plexus block, whereas 30 patients underwent CEA under GA. In the RA group, a carotid shunt was selectively used for patients who exhibited negative results on the awake test. In contrast, such a shunt was used for all patients in the GA group. Results: There were no cases of postoperative stroke, cardiovascular events, or mortality. Nerve injuries were noted in 4 patients (3 in the RA group and 1 in the GA group), but they fully recovered prior to discharge. Operative time and clamp time were shorter in the RA group than in the GA group (119.29±27.71 min vs. 161.43±20.79 min, p<0.001; 30.57±6.80 min vs. 51.77±13.38 min, p<0.001, respectively). The hospital stay was shorter in the RA group than in the GA group (14.6±5.05 days vs. 18.97±8.92 days, p=0.022). None of the patients experienced a stroke or restenosis during the 27.23±20.3-month follow-up period. Conclusion: RA with a reliable awake test reduces shunt use and decreases the clamp and operative times of CEA, eventually resulting in a reduced length of hospital stay.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.4
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• pp.326-332
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• 2021

Swabs are useful and common sampling tools in various research fields, such as medicine, ecology, biotechnology, forensic medicine, and pollutant monitoring systems. Collection reagents are one of the essential components in sampling. It is important to develop a sample collection kit and designate an appropriate storage temperature because samples need to be stored for a long time. The purpose of this study was to identify the effects of three collection reagents and three storage temperatures on the recovery of living bacteria without media. We selected Escherichia coli and Staphylococcus aureus as representative environmental bacteria. Distilled water (DW), phosphate buffered saline (PBS), and Tris-EDTA (TE) buffer were used as collection reagents and stored at 22℃, 4℃, and -70℃ after sampling. The results of using each collection reagent and storage temperature on the bacteria were compared using relative light units (RLU) and the number of colony forming units (CFU). When using -70℃ storage temperature and the TE buffer, the number of living bacteria and the RLU values remained constant. It is therefore recommended that the sample be stored at -70℃ immediately after collection and a TE buffer solution be used as the collection reagent.

• Journal of The Korean Society of Clinical Toxicology
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• v.17 no.1
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• pp.38-41
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• 2019

Procalcitonin (PCT) is commonly employed in medical practice as a diagnostic biomarker of bacterial infection and also as a monitoring biomarker for antimicrobial therapy. There have been a few published reports concerning elevated PCT levels in people with acute liver injury caused by an overdose of acetaminophen. We report here on a case of PCT elevation in an adolescent with acute acetaminophen poisoning without any bacterial infection or liver injury. A 15-year-old girl had deliberately ingested 20 tablets of 650 mg acetaminophen (13 g) and she presented to our emergency department. The PCT level on admission was elevated to 65.64 ng/mL (reference range: 0-0.5 ng/mL). Her PCT level on the second day peaked up to 100 ng/mL and then it gradually decreased. There was no evidence of liver injury or infection on the computed tomography examination and other lab tests. The patient regained her good health and was discharged on the sixth day of hospitalization.

• Fashion & Textile Research Journal
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• v.17 no.6
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• pp.1039-1049
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• 2015

The increase in the need for a 24 hour monitoring of biological signals has been accompanied by an increasing interest in wearable systems that can register ECG at any time and place. ECG-monitoring clothing is a wearable system that records heart function continuously, but there have been difficulties in making accurate measurements due to motion artifacts. Although various factors may cause noise in measurements due to motion, the variations in the body surface and clothing during movements that cause eventual the shifting and displacement of the electrodes is particularly noteworthy. Therefore, this study used biomedical body mapping and a motion-capture system to measure and analyze the changes in the body surface and garment during movements. It was deduced that the area where the friction and separation between the garment and skin is the lowest would be the appropriate location to place the ECG electrodes. For this study, 5 male and 5 female in their 20s were selected as subjects, and through their selected body movements, the changes in the garment and skin were analyzed using the motion-capture system. As a result, the area below the chest circumference and the area below the shoulder blades were proposed as the optimal location of electrode for ECG monitoring.

• Journal of Biomedical Engineering Research
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• v.41 no.1
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• pp.55-61
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• 2020

Recently, there have been many research on fever management using u-healthcare technology. Especially, fever of infants requires continuous monitoring of body temperature by parents. For infants between 4 weeks and under 5 years old, it is recommended to use an electronic thermometer or chemical thermometer in the axilla, or to use an infrared thermometer. However, in order to overcome the reality of not being able to waste significant time on continuous monitoring, there have been demands of patch type thermometers with the internet of things (IoT) and wireless communication technologies. Existing IoT thermometers are difficult to attach to infants' body because they do not take into account its size, and their interoperability is not guaranteed because they do not comply with standards in communication. Therefore, in this study, a patch-type thermometer with a diameter of 20 mm and a weight of 2.9 g was developed to manage the fever of infants, while it communicates wirelessly with Bluetooth Low Energy (BLE) communication protocol and complies with IEEE 11073 PHD(Personal Health Device) at the same time. We verified its performance under the requirements of thermometers regulated by the Korean Ministry of Food and Drug Safety.

• Biomedical Science Letters
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• v.15 no.2
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• pp.135-139
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• 2009

The CA(carbohydrate antigen)19-9 is complex protein that can be used as an important marker which aids the clinical diagnosis and prognosis of various pancreaticobiliary tumors. However, it was also reported that there were some CA19-9 positive patients with benign disease as using RIA method. The purpose of this study is to evaluate the clinical usefulness of serum level of CA19-9 with RIA(radioimmuno assay), CIA(chemiluminescence immuno assay), and conventional liver function tests. The correlation between CIA and RIA in CA19-9 of pancreatobiliary disease was 0.9833(P<0.01). Also, the correlations between CIA and RIA in CA19-9 of benign and malignant pancreaticobiliary tumor patients was 0.8714(P<0.01) and 0.9727(P<0.01) respectively. The correlation between CA19-9 and ALP was 0.5140(P<0.01) and CEA was 0.3385(P<0.05) as using CIA. The measurement of serum CA19-9 levels by CIA method may be useful in differentiating patients with malignant disease from those with benign disease in pancreaticobiliary tumors.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.4
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• pp.268-273
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• 2005

The spirometer is a medical device that measures the instantaneous velocity of the respiratory gas flow capacity. It is used for testing the condition of the lung and patient monitoring. It measures the absolute capacity difference that includes the flow capacity signal. In this paper, by using an ultrasound sensor that reduce+ the error caused by the inertia and pressure it has improved the transmission and receiving signal. This has enabled patients with weak respiratory to use the spirometer. Also, by using the ARM 920T Processor, a precise and prompt detection system was implemented.

• Journal of Biomedical Engineering Research
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• v.35 no.6
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• pp.211-218
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• 2014

The objective of this research is to develop an automatic algorithm based on electrocardiogram (ECG) to estimate slow-wave sleep (SWS). An algorithm is based on 7 indices extracted from heart rate on ECG which simultaneously recorded with standard full night polysomnography from 31 subjects. Those 7 indices were then applied to independent component analysis to extract a feature that discriminates SWS and other sleep stages. Overall Cohen's kappa, accuracy, sensitivity and specificity of the algorithm to detect 30s epochs of SWS were 0.52, 0.87, 0.70 and 0.90, respectively. The automatic SWS detection algorithm could be useful combining with existing REM and wake estimation technique on unattended home-based sleep monitoring.