• 대한방사성의약품학회지
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• 제6권1호
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• pp.27-38
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• 2020

Alzheimer's disease (AD) is one of the challenging conditions that have no cure, yet early diagnosis can help to control the disease. PET imaging of tau has several advantages, such as being a noninvasive, safe diagnostic technique that correlates directly with the disease progression. Many tau tracers have been reported to date; however, the chemical scaffolds of them fall in a narrow chemical window, and none was approved yet as none is entirely selective and sensitive to tau. These problems are being solved as new tracers emerge constantly. In this report, the first-generation tau tracers such as [¹¹C]PBB3, 2-arylquinoline (THK) series, [¹⁸F]T808, and [¹⁸F]AV-1451 ([¹⁸F]T807) are reviewed from an organic and radiochemistry perspective; thus the most effective chemical approach to synthesize these tracers is discussed. This would help to design novel tracers which can meet the challenges faced by the current tracers.

• 한국전문물리치료학회지
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• 제5권2호
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• pp.1-14
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• 1998

This study was conducted to examine the increasing effects of Ga-As-Al laser Koryo-hand acupuncture on experimental pressure threshold. Forty healthy subjects (female=20. male=20) aged 21 to 30 years were randomly assigned to two treatment groups with same ratio in sex. The subjects in the experimental group (n=20) received Ga-As-Al laser stimulation, and those in the control group (n=20) received sham stimulation on appropriate Koryo-hand acupuncture points M10 on the left hand which is reflex point of upper trapezius portion. Experimental pressure threshold at the contralateral upper trapezius was determined with a pressure algometer and Galvanic Skin Response (GSR) before and after treatment. The change of pressure threshold between pretreatment and posttreatment in the experimental group was greater than that in the control group (p<0.05). The result indicates that Ga-As-Al laser Koryo-hand acupuncture increases experimental pressure threshold and suggests that it is an effective noninvasive pain management technique.

• 대한핵의학회지
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• 제38권2호
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• pp.171-174
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• 2004

Angiogenesis, the formation of new capillaries from existing vessels, increases oxygenation and nutrient supply to ischemic tissue and allows tumor growth and metastasis. As such, angiogenesis targeting provides a novel approach for cancer treatment with easier drug delivery and less drug resistance. Therapeutic anti-angiogenesis has shown impressive effects in animal tumor models and are now entering clinical trials. However, the successful clinical introduction of this new therapeutic approach requires diagnostic tools that can reliably measure angiogenesis in a noninvasive and repetitive manner. Molecular imaging is emerging as an exciting new discipline that deals with imaging of disease on a cellular or genetic level. Angiogenesis imaging is an important area for molecular imaging research, and the use of radiotracers offers a particularly promising technique for its development. While current perfusion and metabolism radiotracers can provide useful information related to tissue vascularity, recent endeavors are focused on the development of novel radioprobes that specifically and directly target angiogenic vessels. Presently available proges include RGD sequence containing peptides that target ${\alpha}_v\;{\beta}_3$ integrin, endothelial growth factors such as VEGF or FGF, metalloptoteinase inhibitors, and specific antiangiogenic drugs. It is now clear that nuclear medicine techniques have a remarkable potential for angiogenesis imaging, and efforts are currently continuing to develop new radioprobes with superior imaging properties. With future identification of novel targets, design of better probes, and improvements in instrumentation, radiotracer angiogenesis imaging promises to play an increasingly important role in the diagnostic evaluation and treatment of cancer and other angiogenesis related diseases.

• 대한핵의학회지
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• 제38권5호
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• pp.331-337
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• 2004

Cardiac neurotransmission imaging allows in vivo assessment of presynaptic reuptake, neurotransmitter storage and postsynaptic receptors. Among the various neurotransmitter, I-123 MIBG is most available and relatively well-established. Metaiodobenzylguanidine (MIBG) is an analogue of the false neurotransmitter guanethidine. It is taken up to adrenergic neurons by uptake-1 mechanism as same as norepinephrine. As tagged with I-123, it can be used to image sympathetic function in various organs including heart with planar or SPECT techniques. I-123 MIBG imaging has a unique advantage to evaluate myocardial neuronal activity in which the heart has no significant structural abnormality or even no functional derangement measured with other conventional examination. In patients with cardiomyopathy and heart failure, this imaging has most sensitive technique to predict prognosis and treatment response of betablocker or ACE inhibitor. In diabetic patients, it allow very early detection of autonomic neuropathy. In patients with dangerous arrhythmia such as ventricular tachycardia or fibrillation, MIBG imaging may be only an abnormal result among various exams. In patients with ischemic heart disease, sympathetic derangement may be used as the method of risk stratification. In heart transplanted patients, sympathetic reinnervation is well evaluated. Adriamycin-induced cardiotoxicity is detected earlier than ventricular dysfunction with sympathetic dysfunction. Neurodegenerative disorder such as Parkinson's disease or dementia with Lewy bodies has also cardiac sympathetic dysfunction. Noninvasive assessment of cardiac sympathetic nerve activity with I-123 MIBG imaging nay be improve understanding of the pathophysiology of cardiac disease and make a contribution to predict survival and therapy efficacy.

• 비파괴검사학회지
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• 제33권3호
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• pp.283-288
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• 2013

This paper describes development of a high speed Doppler OFDI system for non-invasive vascular imaging. Doppler OFDI (optical frequency domain imaging) is one of the phase-resolved second generation OCT (optical coherence tomography) techniques for high resolution imaging of moving elements in biological tissues. To achieve a phase-resolved imaging, two temporally separated measurements are required. In a conventional Doppler OCT, a pair of massively oversampled successive A-lines is used to minimize de-correlation noise at the expense of significant imaging speed reduction. To minimize a de-correlation noise between targeted two measurements without suffering from significant imaging speed reduction, several methods have been developed such as an optimized scanning pattern and polarization multiplexed dual beam scanning. This research represent novel imaging technique using frequency multiplexed dual beam illumination to measure exactly same position with aimed time interval. Developed system has been verified using a tissue phantom and mouse vessel imaging.

• 센서학회지
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• 제23권1호
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• pp.7-14
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• 2014

Noncontact electrocardiogram (ECG) measurement using capacitive-coupled technique is a very reliable long-term noninvasive health-care remote monitoring system. It can be used continuously without interrupting the daily activities of the user and is one of the most promising developments in health-care technology. However, ECG signal is a very small electric signal. A robust system is needed to separate the clean ECG signal from noise in the measurement environment. Noise may come from many sources around the system, for example, bad contact between the sensor and body, common-mode electrical noise, movement artifacts, and triboelectric effect. Thus, in this paper, the extended Kalman filter (EKF) is applied to denoise a real-time ECG signal in capacitive-coupled sensors. The ECG signal becomes highly stable and noise-free by combining the common analog signal processing and the digital EKF in the processing step. Furthermore, to achieve ubiquitous monitoring, android-based application is developed to process the heart rate in a realtime ECG measurement.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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• pp.32-32
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• 2003

The purpose of paper is to implement a PC-based software for 3D visualization of brain fiber tractography and high-resolution anatomical data 서론： DTI (Diffusion tensor imaging) is a very useful noninvasive MRI technique for providing the direction and connectivity information of brain fiber tracts. Especially in patients with glioma, fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. To combine information on fiber tracts surrounding turner with a high-resolution anatomical 3D image may be clinically useful for surgical planning. Therefore we implemented a software for visualizing both brain fiber tractography and anatomical data.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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• pp.83-83
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• 2003

Purpose： The purpose of paper is to implement a PC-based software for 3D visualization of brain fiber tractography and high-resolution anatomical data introduction： DTI (Diffusion tensor imaging) is a very useful noninvasive MRI technique for providing the direction and connectivity information of brain fiber tracts. Especially in patients with glioma, fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. To combine information on fiber tracts surrounding tumor with a high-resolution anatomical 3D image may be clinically useful for surgical planning. Therefore we implemented a software for visualizing both brain fiber tractography and anatomical data.

• 대한세포병리학회지
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• 제17권1호
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• pp.18-26
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• 2006

Transitional cell carcinoma of the urinary bladder is common in the genitourinary tract. The gold standard for the diagnosis of bladder cancer has been cystoscopy, along with urine cytology. Cystoscopy is an invasive and relatively expensive technique. By comparison, urine cytology is easy to perform and specific for a diagnosis of bladder cancer, although less sensitive, especially in low-grade tumors. For this reason, there has been a need for superior noninvasive technology to increase our confidence in being able to detect bladder cancer. There are many reports of the various urinary tests that are available to facilitate the diagnosis. In this article, I reviewed the literature on urinary markers and tests that may be clinically useful, including fluorescence in situ hybridization, uCyt+/Immunocyte, the $BTA^{(R)}$ test, the NMP 22TM, the $FDP^{(R)}$ test, the telomerase activity test, the HA and HAse tests, and flow cytometry. Most of these tests have a higher sensitivity and specificity than cytology. However, urine cytology has the highest specificity, especially in individuals with a high-grade tumor. We conclude that no urinary markers or tests can replace the role of cystoscopy along with cytology in the diagnosis of transitional cell carcinoma of the bladder. However, some markers could be used adjunctively to increase the diagnostic accuracy during screening or during the postoperative follow-up examination of patients with bladder cancer.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2002년도 제7차 학술대회 초록집
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• pp.80-80
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• 2002

Purpose： Three tesla high field MR has been important to those disciplines that are SNR limited, such as MR spectroscopy. Additionally, increased spectral dispersion is critical for minimizing spectral overlap and simplifying resonance structures. The purpose of this study was to assess clinical proton MR spectroscopy (MRS) as a noninvasive method for evaluating brain tumor malignancy at 3T high field system Materials and Methods： Using 3T MRI/MRS system, localized water-suppressed single-voxel technique in patients with brain tumors was employed to evaluate spectra with peaks of N-acetyl aspartate (NAA), choline-containing compounds (Cho), creatine/phosphocreatine (Cr) and lactate. On the basis of Cr, these peak areas were quantificated as a relative ratio.