• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2358-2368
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• 2011

Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations, employing the B3LYP method and the LANL2DZ, 6-31G$^*$(LANL2DZ for Tc), 6-31G$^*$(cc-pVDZ-pp for Tc) and DGDZVP basis sets, have been performed to investigate the electronic structures and absorption spectra of the technetium-99m-labeled methylenediphosphonate ($^{99m}Tc$-MDP) complex of the simplest diphosphonate ligand. The bonding situations and natural bond orbital compositions were studied by the Mulliken population analysis (MPA) and natural bond orbital (NBO) analysis. The results indicate that the ${\sigma}$ and ${\pi}$ contributions to the Tc-O bonds are strongly polarized towards the oxygen atoms and the ionic contribution to the Tc-O bonding is larger than the covalent contribution. The electronic transitions investigated by TDDFT calculations and molecular orbital analyses show that the origin of all absorption bands is ascribed to the ligand-to-metal charge transfer (LMCT) character. The solvent effect on the electronic structures and absorption spectra has also been studied by performing DFT and TDDFT calculations at the B3LYP/6-31G$^*$(cc-pVDZ-pp for Tc) level with the integral equation formalism polarized continuum model (IEFPCM) in different media. It is found that the absorption spectra display blue shift in different extents with the increase of solvent polarity.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.243-250
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• 2006

Three novel potential metal ion chelating units have been synthesized and characterized: 5-hexylcarbamoyl-3,4-dihydroxythiophene-2-carboxylic acid methyl ester (5), 3-benzyloxy-4-hydroxythiophene-2,5-dicarboxylic acid bis-hexylamide (6), and 3,4-dihydroxythiophene-2,5-dicarboxylic acid bis-hexylamide (7). The crystal structure of 6 was obtained and suggests the presence of three distinct intramolecular hydrogen bonds, namely $[N_{amide}-H{\cdot}{\cdot}{\cdot}O]$ $[O-H{\cdot}{\cdot}{\cdot}O_{amide}]$ and $[N_{amide}-H{\cdot}{\cdot}{\cdot}S]$. Boron chelation with 5, 6 and 7 through the use of $BF_3, \;B(OH)_3 \;or \;B(OMe)_3$ was probed by $^1H$, $^{11}B$, and $^{13}C$ NMR spectroscopy. Technetium (I) chelation with 5, 6 and 7 was also studied via HPLC elutions using $[^{99m}Tc(CO)_3(OH_2)_3]^+$.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1439-1444
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• 2002

6-Nitroquipazine has higher binding affinity for SERT than other selective serotonin reuptake inhibitors. We have prepared 6-nitroquipazine based rhenium complexes which would lead to the development of potential SPECT imaging agents with $^{99m}Tc$ for 5-HT transporter.

• 핵의학기술
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• 제27권1호
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• pp.4-6
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• 2023

Technetium-labeled phosphate bone scan was shown to detect bone fractures and bone metastasis in early stage than general radiographs. Therefore, bone scan has become one of the most frequently performed nuclear medicine imaging examination. However, non-osseous radiopharmaceutical uptake on the bone scan are unusual findings. We report a case of diffuse splenic absorption of Tc-99m dicarboxypropane diphosphonate in patients who undergo liver transplantation.

• 대한핵의학회지
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• 제24권2호
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• pp.237-243
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• 1990

Pulmonary embolism demands rapid and accurate diagnosis. And ventilation imaging has greatly improved the diagnostic accuracy of pulmonary embolism in addition to perfusion imaging. Agents currently used include xenon-133, krypton-81m and technetium-99m radioaerosols. However radioactive gases are compromised by availability and cost for krypton-81m, radiation dose, gamma energy and non?physiologic behaviour for xenon-133. Radioaerosols of technetium-99m componds are rapidly cleared from the lung after inhalation, and their relative low effeciency (specific radioactivity) and wide distribution of particle sizes make them also suboptimum. A new ventilation agent, Technegas is a suspension of structured graphite ellipsoids with diameter below 20nm, labelled with $^{99m}Tc$ in a carrier gas of Argon. This report describes the authors' clinical experience with Technegas. This is the first reported clinical study of this agent in Korea. A comparison of Technegas and $^{99m}Tc-DTPA$ aerosol was performed in 12 patients with various pulmonary diseases such as COPD, pulmonary tuberculosis and pleural effusion. All patients were studied with $^{99m}Tc-DTPA$ aerosol inhalation and Technegas ventilation. In both studies image quality was assessed (1) semiquantitatively by scoring bronchial and gastric activity, (2) subjectively by direct visual comparison of peripheral lung images and (3) quantitatively by computing the peripheral penetration index(PI) for each lungs. The bronchial activites were seen in 7 out of 12 cases with $^{99m}Tc-DTPA$ aerosol and in 5/12 with Technegas. The gastric activities were seen in 5/12 and 1/12 cases respectively. The average values of PI were 61.26% with $^{99m}Tc-DTPA$ aerosol and 69.20% with Technegas (p>0.05). Using $^{99m}Tc-DTPA$ aerosol, COPD patients showed deposition in the central airways with poor visualization of the peripheral areas of the lungs. In Technegas studies these phenomena were less prominent, and the examination is well tolerated by pateients and requires only a minimum of patient cooperation. With superiority of easy availability and handling, better physical characteristics and favorable Image quality, Technegas is a Promising agent for lung ventilation scanning.

• Journal of Yeungnam Medical Science
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• 제5권2호
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• pp.171-174
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• 1988

Tc99-IDAs를 이용하여 원발성 간세포암뿐만 아니라 폐에 전이된 간세포암까지 확인할 수 있다는 보고가 있었기에 저자들은 원발성 간세포암에서 폐전이가 의심되는 환자에게 Tc99m-DISIDA를 이용하여 간 및 폐를 주사하여 흉부 X-선상의 폐전이와 일치하는 주사상의 열소를 확인하였으며 이는 우리나라에 많은 간세포암의 진단과 수술전 전이유무의 평가 및 치료설정에 도움이 될 수 있을 것으로 생각되어 보고하고자 한다.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1990년도 제29차 춘계학술대회
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• pp.214-214
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• 1990

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1990년도 제29차 춘계학술대회
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• pp.209.2-210
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• 1990

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 2003년도 추계학술대회 및 총회
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• pp.15.2-15.2
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• 2003

• 대한핵의학회지
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• 제30권3호
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• pp.379-381
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• 1996

Tc-99m-MIBI는 비특이적 반응으로 양성 비종양성 질환의 일종인 활동성 폐결핵에 섭취가 증가되며, 이의 치료 후 추적 관찰에도 유용할 것으로 생각된다. 특히 만성 폐결핵 환자에 있어 방사선학적으로나 객담검사는 음성이었으나 재발이 의심될 때, tuberculin skin test 상 양성이나 단순 흉부 검사상 확실치 않을 때 유용하게 이용되리라 사료된다.