• The Korean Journal of Nuclear Medicine
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• v.33 no.2
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• pp.120-130
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• 1999

Purpose: This study was performed to evaluate the diagnostic usefulness of double-phase Tc-99m MIBI parathyroid scintigraphy with single photon emission computed tomography (SPECT) in patients with hyper-parathyroidism. We also evaluated the relationship between Tc-99m MIBI uptake and oxyphil cell contents in parathyroid glands. Materials and Methods: The subjects were 28 parathyroid glands of 10 patients who underwent Tc-99m MIBI parathyroid scintigraphy and parathyroidectomy for clinically suspected hyper-parathyroidism. Early and delayed pinhole images were obtained at 15 minutes and 2 hours after injection of Tc-99m MIBI, and SPECT images were followed. The weight and oxyphil cell contents of parathyroid tissue were obtained from pathologic specimen, and the scintigraphic findings were compared with histopathology. Results: In surgical histopathology, 6 parathyroid adenomas and 9 parathyroid hyperplasias were confirmed. The sensitivity, specificity, and positive predictive value of early and delayed images were 46.7% (7/15), 76.9% (10/13), 70% (7/10) and 66.7% (10/15), 92.3% (12/13), 90.9% (10/11), respectively. SPECT image detected an additional small hyperplasia.. The sensitivity, specificity, and positive predictive value of combined interpretation of early and delayed images with SPECT were 73.3% (11/15), 100% (13/13), 100% (11/11). The sensitivity was 100% (6/6) for adenoma, whereas that was 55.5% (5/9) for hyperplasia. Both adenomas and hyperplasias showed significantly increased oxyphil cell contents compared with normal parathyroid glands (p<0.0001), but the oxyphil cell content and weight were not significantly different between adenomas and hyperplasias. Conclusion: Double-phase Tc-99m MIBI parathyroid scintigraphy with SPECT is useful for lesion localization in patients with hyperparathyroidism. Although both adenoma and hyperplasia have increased oxyphil cell content, the sensitivity is high in adenoma, but low in hyperplasia.

• Progress in Medical Physics
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• v.12 no.1
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• pp.51-58
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• 2001

Synchrotron radiation (SR) has several advantages over convetional x-rays, including its phase, collimation, and high flux. A synchrotron radiation beamline 5C1 at Pohang Light Source (PLS) was recently built for imaging applications. We have shown that a SR imaging system is useful in imaging microscopic structures. SR with broad-band energy spectrum were adjusted to an object by Si wafers and their energy were approximately ranging from 6 keV to 30 keV. SR were passed through an object and finally transformed into visible lights by CdWO$_4$ scintillator screen. The visible lights which were reflected at an angle of 90 degrees by gold plated mirror were detected by a CCD camera and the image data were acquired using image acquisition system. A high-resolution phantom, capacitor, adult tooth, child tooth, cancerous breast tissue, and mouse lumbar vertebra were imaged with SR imaging system. The Objects were rotated within the field of view of the CCD detector, and their projection image data were obtained at 250 steps over 180 degrees rotation. Image reconstructions were carried out in a PC by using IDLTM(Research systems, Inc., US) program. The spatial resolution of the images acquired by the SR imaging system was measured with a high-resolution chart manufactured for several micrometer resolution. The specimens were also imaged with conventional x-ray radiography system to compare the image quality of radiography obtained with the SR imaging system. The results showed more structural details and high contrast images with SR imaging system than conventional x-ray radiography system. The SR imaging system may have a potential for imaging in biological researches, material applications, and clinical radiography.

• Investigative Magnetic Resonance Imaging
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• v.2 no.1
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• pp.96-103
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• 1998

Purpose : To assess the clinical utility of turbo contrast-enhanced magnetic resonance angiography(CE MRA) in the evaluation of the aortic arch and its major branches and to compare the image quality of CE MRA among different coils used. Materials and Methods : Turbo three-phase dynamic CE MRA encompassing aortic arch and its major branches was prospectively performed after manual bolus IV injection of contrast material in 29 patients with suspected cerebrovascular diseases at 1.0T MR unit. the raw data were obtained with 3-D FISH sequence (TR 5.4ms, TE 2.3ms, flip angle 30, slab thickness 80nm, effective slice thickness 4.0mm, matrix size $100{\times}256$, FOV 280mm). Total data acquisition time was 4. to 60 seconds. We subjectively evaluated the imge quality with three-rating scheme : "good" for unequivocal normal finding, "fair" for relatively satisfactory quality to diagnose 'normal' despite intravascular low signal, and "poor" for equivocal diagnosis or non-visualization of the origin or segment of the vessels due to low signal or artifacts which needs catheter angiography. At the level of the carotid bifurcation, it was compared with conventional 2D-TOF MRA image. Overall image quality was also compared visually and quantitatively by measuring signal-to-noise ratios (SNRs) of the ascending aorta, the innominate artery and both common carotid arteries among the three different coils used(CP body array(n=12), CP neck array(n=9), and head-and-neck(n=8). Results : Demonstration of the aortic arch and its major branches was rated as "good" in 55% (16/29) and "fair" in 34%(10/29). At the level of the carotid bifurcation, image quality of turbo CE MRA was same as or better than conventional 2D-TOF MRA in 65% (17/26). Overall image quality and SNR were significantlygreater with CP body array coil than with CP neck array or head-and-neck coil. Conclusions : Turbo CE MRA can be used as a screening exam in the evaluation of the major branches of the aortic arch from their origin to the skull base. Overall imagequality appears to be better with CP body array coil than with CP neck array coil or head-and-neck coil.

• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.171-180
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• 2006

Peroxisome proliferatorr-activated receptor-gamma $(PPAR{\gamma})$ must form a heterodimer with the retinoid-X receptor (RXR) to bind DNA, and its transcriptional activity is thought to be maximized by ligands specific for either receptor. Activated $(PPAR{\gamma})$ and $(PPAR{\gamma})$ ligands may influence tumor growth through regulation of the tumor suppressor PTEN. Our aim in this study was to determine whether co-stimulation with the $(PPAR{\gamma})$ ligand, ciglitazone, and RXR ligand can synergistically upregulate PTEN in human acute promyelocytic leukemia (APL) cells and consequently potentate the inhibition of cell growth and cell cycle progression of these cells. Human leukemia cell line, HL-60 cells were exposed to all-trans-retinol and ciglutazone. The PTEN expression was measured as the level of PTEN mRNA expression by RT-PCR and as the level of PTEN expression by western blot analysis. Cell cycle analysis was carried out by a propidium iodide (PI) staining method and analyzed with a FACScan. The $(PPAR{\gamma})$ ligand, ciglitazone, and the RXR ligand, retinoic acid, upregulated PTEN expression by HL-60 cells in time- and dose-dependent manners, respectively. This was significantly enhanced by a combination of both ciglitazone and retinoic acid. Moreover, these compounds synergistically induced arrests of both cell growth and the $G_l$ phase of the cell cycle. Thus, the activation of the $(PPAR{\gamma})$:RXR heterodimer may represent a regulatory pathway for human leukemia cells and there may be important roles for $(PPAR{\gamma})$ and RXR ligands in prophylactic and therapeutic approaches fur controlling leukemia through the upregulation of PTEN.

• The Korean Journal of Pain
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• v.19 no.1
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• pp.81-86
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• 2006

Background: Complex regional pain syndrome (CRPS) is a painful and disabling disease, yet the diagnosis of this can be difficult to confirm by purely objective measures. Therefore, we performed three-phasic bone scans and thermography as a work up in order to determine their predictive value and usefulness for making the diagnosis of CRPS. Methods: 44 patients who had been diagnosed with CRPS type-1, according to the modified criteria, were evaluated. All the patients were examined by performing a three-phasic bone scan and thermography as part of a work-up for diagnostic confirmation. The diffuse increased tracer uptake in the delayed image (phase III) was estimated by the positive findings. The findings were considered positive for CRPS if the thermographic findings showed temperature asymmetries between the affected and non- affected extremities of more than $1.00^{\circ}C$ Results: A review of the three-phasic bone scan for 44 patients indicated that 16 patients (36.4%) had diffusely positive scans, and thermographic abnormalities were noted in 35 of 44 patients (79.5%). Conclusions: The use of thermography in clinical settings can play an important role in the diagnosis of CRPS. However, a three-phasic bone scan alone cannot provide a completely accurate diagnosis, so it is imperative that the three-phasic bone scan data be integrated with the clinical evaluation and the other relevant tests.

• Journal of Korean Neurosurgical Society
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• v.63 no.2
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• pp.188-201
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• 2020

Objective : The purpose of this study was to suggest that computed tomography angiography (CTA) is valuable as the only preliminary examination for mechanical thrombectomy (MT). MT after single examination of CTA including noncontrast computed tomography (NCCT) and maximum intensity projection (MIP) improves door-to-puncture time as well as results in favorable outcomes. Methods : A total of 157 patients who underwent MT at Dong Kang Medical Center from April 2015 to March 2019 were divided into two groups based on the examination performed prior to MT : CTA group who underwent CTA with NCCT and MIP, and NCCT+magnetic resonance image (MRi) group who underwent MRI including perfusion images after NCCT. In the two groups, time to CTA imaging or NCCT+MRi imaging after symptom onset, and time to arterial puncture and reperfusion were characterized as time-related outcomes. The evaluation of vascular recanalization after MT was defined as a modified thrombolysis in cerebral infarction (mTICI) scale. National Institutes of Health Stroke Scale (NIHSS) was assessed at the time of the visit to the emergency room and modified Rankin Scale (mRS) was assessed after 90 days. Results : Typically, there were 34 patients in the CTA group and 33 patients in the NCCT+MRi group. A significantly shorter delay for door-to-puncture time was observed (mean, 86±22.1 vs. 176±47.5 minutes; <0.01). Also, a significantly shorter door-to-imege time in the CTA group was observed (mean, 13±6.8 vs. 93±30.8 minutes; p<0.01). Moreover, a significantly shorter onset-to-puncture time was observed (mean, 195±128.0 vs. 314±157.6 minutes; p<0.01). Reperfusion result of mTICI ≥2b was 100% (34/34) in the CTA group and 94% (31/33) in the NCCT+MRi group, and mTICI 3 in 74% (25/34) in the CTA group and 73% (24/33) in the NCCT+MRi group. Favorable functional outcomes (mRS score ≤2 at 90 days) were 68% (23/34) in the CTA group and 60% (20/33) in the NCCT+MRi group. Conclusion : A single-phase CTA including NCCT and MIP images was performed as a single preliminary examination, which led to a reduction in the time of the procedure and resulted in good results of prognosis. Consequently, it is concluded that this method is of sufficient value as the only preliminary examination for decision making.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.6
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• pp.436-441
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• 1998

$Pt/SrTiO_3/Pb_x(Zr_{0.52}, Ti_{0.48})O_3/SrTiO_3/Si$ structure was prepared by rf-magnetron sputtering method for use in nondestructive read out ferroelectric RAM(NDRO-FEAM). PBx(Zr_{0.52}Ti_{0.48})O_3}$(PZT) and $SrTiO_3$(STO) films were deposited respectively at the temperatures of $300^{\circ}C and 500^{\circ}C$on p-Si(100) substrate. The role of the STO film as a buffer layer between the PZT film and the Si substrate was studied using X-ray diffraction (XRD), Auger electron spectroscopy (ASE), and scanning electron microscope(SEM). Structural analysis on the interfaces was carried out using a cross sectional transmission electron microscope(TEM). For PZT/Si structure, mostly Pb deficient pyrochlore phase was formed due to the serious diffusion of Pb into the Si substrate. On the other hand, for STO/PZT/STO/Si structure, the PZT film had perovskite phase and larger grain size with a little Pb interdiffusion. the interfaces of the PZT and the STO film, of the STO film and the interface layer and $SiO_2$, and of the $SiO_2$ and the Si substate had a good flatness. Across sectional TEM image showed the existence of an amorphous layer and $SiO_2$ with 7nm thickness between the STO film and the Si substrate. The electrical properties of MIFIS structure was characterized by C-V and I-V measurements. By 1MHz C-V characteristics Pt/STO(25nm)/PZT(160nm)/STO(25nm)/Si structure, memory window was about 1.2 V for and applied voltage of 5 V. Memory window increased by increasing the applied voltage and maximum voltage of memory window was 2 V for V applied. Memory window decreased by decreasing PZT film thickness to 110nm. Typical leakage current was abour $10{-8}$ A/cm for an applied voltage of 5 V.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.1
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• pp.63-76
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• 1999

The main objective of this study was to develop a concept of service marketing promotion in nursing that is derived from the concepts of service marketing theory. This research was a descriptive study, at the factor isolation level. The principle of concept derivation suggested by Walker and Avant (1988) and the Hybrid model suggested by Schwarz-Barcott and Kim (1993) were employed as the research method. The data were collected from December, 1997 to April. 1998 at a large general hospital located in Seoul. The procedures of this study were as follows: First. at the theoretical phase: the meaning, attributes, and definition of service marketing promotion were identified through an extensive review of the literature. Second, at the empirical phase: fieldwork was done to identify the promotional activities and events in nursing. Top nurse managers from 4 units (Director of Nursing, Head nurses of inpatient nursing unit, outpatient nursing unit. and home care nursing unit) were interviewed and the content of the interview was analyzed to identify the meaning and attributes of promotion in nursing. Other methods such as brochures and other audio-visual materials which were relevant to nursing promotion were used to supplement the interviews. Finally, the results of the theoretical and empirical analyses were intergrated to develop a concept of service marketing in nursing practice. A final definition of service marketing promotion in nursing was identified as follows. 1. Promotion as a marketing function in nursing service is concerned with communication to target markets on all information related to nursing service in order to satisfy the objectives of both a nursing service organization and the target markets. 2. The goals of nursing service promotion include: 1) increasing visibility of nursing services and delivering the information on nursing services, 2) affirming the value of nursing services, so it can contribute to formulation of reimbursement policy for nursing services. 3) advancing the general image of the nursing profession and nursing services. 4) achieving and attaining a desirable positioning for nurses among health care professionals. and 5) creating and stimulating the demand for nursing services. 3. In order to obtain these goals it is necessary to provide information on nursing services, to persuade target markets. to remind them about nursing services. and to establish a collaborative relationship with related departments. 4. The tools used to carry out the above functions of promotion in nursing are the providing nursing services, public relations and publicity. QA of nursing, advertising, and sales promotion. 5. The target markets of nursing service include the nursing customer markets. the internal markets, the influence markets. the recruitment markets. the supplier markets. and the nursing referral markets. In conclusion, the concept of promotion in other service marketing areas can be applied to the promotion of nursing service marketing. The promotion of nursing service is more than just effective communication in nursing service. it is the effective use of the concepts of service marketing promotion. Promotion of nursing service will contribute to create and expand nursing services.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.4
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• pp.443-451
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• 2010

This paper describes a fully integrated CMOS low-IF mobile-TV RF tuner for Band-III T-DMB/DAB applications. All functional blocks such as low noise amplifier, mixers, variable gain amplifiers, channel filter, phase locked loop, voltage controlled oscillator and PLL loop filter are integrated. The gain of LNA can be controlled from -10 dB to +15 dB with 4-step resolutions. This provides a high signal-to-noise ratio and high linearity performance at a certain power level of RF input because LNA has a small gain variance. For further improving the linearity and noise performance we have proposed the RF VGA exploiting Schmoock's technique and the mixer with current bleeding, which injects directly the charges to the transconductance stage. The chip is fabricated in a 0.18 um mixed signal CMOS process. The measured gain range of the receiver is -25~+88 dB, the overall noise figure(NF) is 4.02~5.13 dB over the whole T-DMB band of 174~240 MHz, and the measured IIP3 is +2.3 dBm at low gain mode. The tuner rejects the image signal over maximum 63.4 dB. The power consumption is 54 mW at 1.8 V supply voltage. The chip area is $3.0{\times}2.5mm^2$.

• Progress in Medical Physics
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• v.27 no.4
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• pp.203-212
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• 2016

Dose differences between three-dimensional (3D) and four-dimensional (4D) doses could be varied according to the geometrical relationship between a planning target volume (PTV) and an organ at risk (OAR). The purpose of this study is to evaluate the correlation between the overlap volume histogram (OVH), which quantitatively shows the geometrical relationship between the PTV and OAR, and the dose differences. 4D computed tomography (4DCT) images were acquired for 10 liver cancer patients. Internal target volume-based treatment planning was performed. A 3D dose was calculated on a reference phase (end-exhalation). A 4D dose was accumulated using deformation vector fields between the reference and other phase images of 4DCT from deformable image registration, and dose differences between the 3D and 4D doses were calculated. An OVH between the PTV and selected OAR (duodenum) was calculated and quantified on the basis of specific overlap volumes that corresponded to 10%, 20%, 30%, 40%, and 50% of the OAR volume overlapped with the expanded PTV. Statistical analysis was performed to verify the correlation with the OVH and dose difference for the OAR. The minimum mean dose difference was 0.50 Gy from case 3, and the maximum mean dose difference was 4.96 Gy from case 2. The calculated range of the correlation coefficients between the OVH and dose difference was from -0.720 to -0.712, and the R-square range for regression analysis was from 0.506 to 0.518 (p-value <0.05). However, when the 10% overlap volume was applied in the six cases that had OVH value ${\leq}2$, the average percent mean dose differences were $34.80{\pm}12.42%$. Cases with quantified OVH values of 2 or more had mean dose differences of $29.16{\pm}11.36%$. In conclusion, no significant statistical correlation was found between the OVH and dose differences. However, it was confirmed that a higher difference between the 3D and 4D doses could occur in cases that have smaller OVH value.