• Title/Summary/Keyword: high-Tc

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Characterization of Tetracycline Resistance Plasmids of Staphylococcus aureus (황색포도상구균의 테트라사이클린 내성 플라스미드 동정)

  • Park, Jung-Hee;Lee, Jae-Yoon;Moon, Kyung-Ho
    • YAKHAK HOEJI
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    • v.52 no.4
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    • pp.279-282
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    • 2008
  • Plasmids were isolated from 15 tetracycline (Tc) resistant S. aureus. Two small tetracycline resistance plasmids, pKH16 and pKH17, have been isolated from Staphylococcus aureus JY10 and Staphylococcus aureus JY22, respectively and the complete nucleotide sequences of those plasmids have been determined. pKH16 consisted of 4,442 bp and showed high identity to pKH6 (99% matching percentage) isolated in 1989 from S. aureus SA2. pKH17 consisted of 4,441 bp and showed less identity to pKH6 (95% matching percentage) than pKH16. PCR analysis showed that tetK and tetM did not exist in ten large plasmids isolated from ten Tc resistant S. aureus. Twelve Tc resistant S. aureus showed reistance both to Tc and Mn and we might analogize that twelve Tc resistant S. aureus had tetM in their chromosome.

[ $^{99m}Tc$ ] Generator Safety Simulation Based on GEANT4 (GEANT4를 이용한 $^{99m}Tc$ Generator 안전성 시뮬레이션)

  • Kang, Sang-Koo;Han, Dong-Hyun;Kim, Chong-Yeal
    • Progress in Medical Physics
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    • v.19 no.1
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    • pp.1-8
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    • 2008
  • Technisium $(^{99m}Tc)$ is one of the most widely used radioactive isotopes for diagnosis in nuclear medicine. In general, technisium is produced inside the so called $^{99m}Tc$ generator which is usually made out of lead to shield relatively high energy radiation from $^{99}Mo$ and its daughter nuclide $^{99m}Tc$. In this paper, a GEANT4 simulation is carried out to test the safety of the $^{99m}Tc$ generator, taking the Daiichi product with radioactivity of 500 mCi as an example. According to the domestic regulation on radiation safety, the dose at 10 cm and 100 cm away from the surface of shielding container should not exceed 2.0 mSv/h and 0.02 mSv/h, respectively. The simulated dose turned out to be less than the limit, satisfying the domestic regulation.

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Is $^{201}Tl-^{99m}Tc$-Subtraction Scan an Accurate Diagnostic Method to Detect Parathyroid Mass? ($^{201}Tl/^{99m}Tc$ 감영스캔으로 부갑상선종괴를 얼마나 찾을 수 있는가?)

  • Yang, Hyung-In;Kim, Deog-Yoon;Kim, Kwang-Won;Choi, Young-Kil
    • The Korean Journal of Nuclear Medicine
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    • v.28 no.1
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    • pp.31-36
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    • 1994
  • We studied 65 patients with hypercalcemia who had heed performed $^{201}Tl/^{99m}Tc$ subtraction scan, 21 of them were confirmed as parathyroid tumor (19 adenoma, 2 carcinoma). The diagnostic sensitivity of $^{201}Tl/^{99m}Tc$ subfraction scan for detecting parathyroid mass was 90.5%, specificity was 97.6%, ultrasonography was 80.6%, 58.8%, respectively. The causes of two false negative cases were relatively small size ($1.5{\times}1{\times}0.8cm$) compared to remainig cases and poor thallium uptake due to cystic necrosis of parathyroid adenoma. The one false positive case was non-functioning thyroid nodule. $^{201}Tl/^{99m}Tc$ subtraction scan was simple, effective diagnostic tool and superior to ultrasonography for evaluating the parathyroid mass with high sensitivity and specificity.

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Induction of Genetic Variation with Recurrent Gamma Radiation in Centipedegrass (Eremochloa ophiuroides) (감마선 순환 처리에 의한 Centipedegrass (Eremochloa ophiuroides)의 유전변이 유도)

  • Lim, Keun Bal;Hanna, Wayne. W.;Rim, Yong Woo;Kim, Young Jin;Han, Hak Suk;Sung, Byung Ryeol;Kim, Jun Sik
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.18 no.4
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    • pp.351-354
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    • 1998
  • Centipedegrass (Eremochloa ophiuroides) is a popular lawn grass in the southeastern USA. It has a naturally light green color and grows well on a wide range of soil types. Studies show limited morphological variation present in centipedegrass germplasm. To obtain the high morphological variation, plants were established from the irradiated seed at 10 Kr, allowed to interpollinate and harvested bulk seed, and then irradiated again for the next cycles. Morphological characteristics were measured in the 5 genetic varition lines (TC201 : cv. Common and non irradiated, TC202 : 4th cycles, TC241 : 6th cycles, TC306 : 8th cycles, and TC318 : 5th cycles) induced by recurrent gamma radiation. The ranges of variation of recurrently radiated centipedegrass lines < TC202, TC241 and TC306 except TC318(TifBlair) > for the stolons per plant, total stolon length per plant, longest stolon length, leaf length and width at top-most exposed internode were wider than those of non-irradiated line (TC201). Recurrent gamma radiation was very effective to enlarge the ranges of variation of morphological characteristics in reproductive organ like stolons of centipedegrass. The effect of quantity of gamma ray irradiation cycles on the means and ranges of variation in the morphological characteristics of centipedegrass was not regularly tended.

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Comparison of Lipid Profile Ratios in Patients with High-grade Brain Cancers according to the Presence of Recurrence during Cancer-related Therapy (항암치료 받는 악성 뇌종양 환자의 재발여부에 따른 지질프로필 비율의 비교)

  • Kim, Sanghee
    • Journal of Korean Biological Nursing Science
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    • v.19 no.2
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    • pp.107-112
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    • 2017
  • Purpose: The purpose of this study was to identify the lipid profile ratios as factors affecting disease progress in patients with high-grade primary brain cancers undergoing concurrent chemoradiotherapy (CCRT) and adjuvant chemotherapy. Methods: The levels of lipid profile ratios were evaluated by looking at the total cholesterol (TC) to high-density lipoprotein (HDL)-cholesterol (TC/HDL-c), low-density lipoprotein (LDL)-cholesterol to HDL-cholesterol (LDL-c/HDL-c), and triglycerides to HDL-cholesterol (TG/HDL-c). This descriptive research was conducted 7 months after the initiation of CCRT and adjuvant chemotherapy. Results: A total of 36 patients with newly diagnosed primary malignant brain cancer were included in the study. The levels of lipid profile ratios such as TC/HDL-c, LDL-c/HDL-c, TG/HDL-c were significantly different between the patients with and without disease progress at 7 months after initiation of CCRT and adjuvant chemotherapy. Conclusion: The lipid profile ratios were indicators affecting disease prognosis with tumor-related factors at 7 months after initiation of CCRT and adjuvant chemotherapy. Therefore, lipid profile ratios indicating hyperlipidemia in patients with high-grade brain cancers should be carefully monitored during and after cancer-related therapy.

$Site-Specific^{99m}$Tc-Labeling of Antibody Using Dihydrazinoph-thalazine (DHZ) Conjugation to Fc Region of Heavy Chain

  • Jeong, Jae-Min;Lee, Jae-Tae;Paik, Chang-Hum;Kim, Dae-Kee;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • Archives of Pharmacal Research
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    • v.27 no.9
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    • pp.961-967
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    • 2004
  • The development of an antibody labeling method with $^{99m}$Tc is important for cancer imaging. Most bifunctional chelate methods for $^{99m}$Tc labeling of antibody incorporate a $^{99m}$Tc chelator through a linkage to lysine residue. In the present study, a novel site-specific $^{99m}$Tc labeling method at carbohydrate side chain in the Fc region of 2 antibodies (T101 and rabbit anti-human serum albumin antibody (RPAb)) using dihydrazinophthalazine (DHZ) which has 2 hydrazino groups was developed. The antibodies were oxidized with sodium periodate to pro-duce aldehyde on the Fc region. Then, one hydrazine group of DHZ was conjugated with an aldehyde group of antibody through the formation of a hydrazone. The other hydrazine group was used for labeling with $^{99m}$Tc. The number of conjugated DHZ was 1.7 per antibody. $^{99m}$Tc labeling efficiency was 46-85% for T101 and 67∼87% for RPAb. Indirect labeling with DHZ conjugated antibodies showed higher stability than direct labeling with reduced antibodies. High immunoreactivities were conserved for both indirectly and directly labeled antibodies. A biodistribution study found high blood activity related to directly labeled T1 01 at early time point as well as low liver activity due to indirectly labeled T101 at later time point. However, these findings do not affect practical use. No significantly different biodistribution was observed in the other organs. The research concluded that DHZ can be used as a site-specific bifunctional chelating agent for labeling antibody with $^{99m}$Tc. Moreover, $^{99m}$Tc labeled antibody via DHZ was found to have excellent chemical and biological properties for nuclear medicine imaging.edicine imaging.

Design of the Successive Selection Encoder by the Logical Effort for High Flash Speed ADC's (고속 플래시 AD 변환기를 위한 Successive Selection Encoder의 Logical Effort에 의한 설계)

  • Lee Kijun;Choi Kyusun;Kim Byung-soo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.4 s.334
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    • pp.37-44
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    • 2005
  • In this paper, a new type of the TC-to-BC encoder for high speed flash ADC's, called the Successive Selection Encoder (SSE), is proposed. In contrast to the conventional fat tree encoder based on OR operations, the W- outputs, in the new design, are obtained directly from TC inputs through simple MUX operations. The detailed structure of the SSE has been determined systematically by the method of the logical effort and the simulation oil Hynix 0.25um process. The theoretical and experimental results show that (1) it is not required to generate one-out-of-n signals, (2) the number of gates is reduced by the factor of 1/3, and (3) the speed is improved more than 2-times, compared to the fat tree encoder. It is speculated that the SSE proposed in this study is an effective solution for bottleneck problems in high speed ADCs.

Reliability Characteristics of a Package-on-Package with Temperature/Humidity Test, Temperature Cycling Test, and High Temperature Storage Test (온도/습도 시험, 온도 싸이클링 시험 및 고온유지 시험에 따른 Package-on-Package의 신뢰성)

  • Park, Donghyun;Oh, Tae Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.23 no.3
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    • pp.43-49
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    • 2016
  • Reliability characteristics of thin package-on-packages were evaluated using T/H (temperature/humidity) test at $85^{\circ}C/85%$ for 500 hours, TC (temperature cycling) test at $-40{\sim}100^{\circ}C$ for 1,000 cycles, and HTS (high temperature storage) test at $155^{\circ}C$ for 1,000 hours. The average resistance of the solder-bump circuitry between the top and bottom packages of 24 package-on-package (PoP) samples, which were processed using polyimide thermal tape, was $0.56{\pm}0.05{\Omega}$ and quite similar for all 24 samples. Open failure of solder joints did not occur after T/H test for 500 hours, TC test for 1,000 cycles, and HTS test for 1,000 hours, respectively.

Thallium-201 Scan in Bone and Softtissue Sarcoma - Comparison with Tc-99m-MIBI and Tc-99m-MDP Scan - (악성 골 및 연부조직 종양에서 Tl-201 SCAN의 진단적 효능 - Tc-99m-MIBI 및 Tc-99m-MDP scan과의 비교 -)

  • Shin, Duk-Seop;Cho, Ihn-Ho;Ahn, Jong-Chul;Ahn, Myun-Hwan;Lee, Sang-Ho
    • The Journal of the Korean bone and joint tumor society
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    • v.2 no.1
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    • pp.1-7
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    • 1996
  • PURPOSE : The purpose of this study is to know the ability of detecting malignant tumor tissue by Tl-201 scan, and to compare with that of Tc-99m-MIBI and Tc-99m-MDP scan. MATERIAL AND METHODS : Between February 1994 and December 1995,38 unselected patients with various bone pathologies were studied prospectively. Eighteen had malignant bone and soft tissue pathologies, while twenty had benign. All patients were studied with Tl-201, Tc-99mMIBI and Tc-99m-MDP scan prior to surgical biopsy. PICKER Prism 2000 gamma camera with high resolution parallel hole collimator was used for scanning. To avoid the interaction of isotope, the early(30min.) and delayed phase(3hrs.) of Tl-20l scan was performed first and Tc-99m-MIBI scan was performed after 30 minutes, and then Tc-99m-MDP scan 48 hours later. The scan images were visually evaluated by a blinded nuclear medicine physician. We could find true positive, true negative, false positive and false negative by the comparison of results with those of biopsy. We calculated positive and negative predictive value(%), sensitivity(%), specificity(%) and diagnostic accuracy(%) of each scan. RESULT : The results of each scan were 85.7, 100, 100, 85, 92.1% in Tl-201, 81, 94.1, 94.4, 80, 86.8% in Tc-99m-MIBI and 50, 66.7, 88.9, 20, 52.6% in Tc-99m-MDP scan. As a conclusion, Tl-201 scan was the most specific and accurate method for detecting malignant tumor tissue. Tc-99m-MIBI scan was also good for malignant tumor searching. CONCLUSION : With our results, we can use Tl-201 scan to differentiate benign from malignant tumor, and to evaluate the response of preoperative chemotherapy or radiotherapy, and to determine the residual tumor or local recurrence. For the better result, we need to have a more detail information about false positive cases and a more objective and quantitative reading technique.

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Estimation of the Arterial Fraction of Total Hepatic Flow from Radionuclide Angiogram Using $^{99m}Tc-DISIDA$ ($^{99m}Tc-DISIDA$를 이용한 간 혈류 중 동맥 분획의 측정)

  • Lee, Hae-Giu;Lim, Gye-Yeon;Yang, Il-Kwon;Kim, Hack-Hee;Lim, Jung-Ik;Bahk, Yong-Whee;Han, Sok-Won;Han, Nam-Ik;Lee, Young-Sok
    • The Korean Journal of Nuclear Medicine
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    • v.25 no.2
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    • pp.200-206
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    • 1991
  • Arterial fraction of total hepatic blood flow was estimated by a new method, slope method, on radionuclid angiogram using $^{99m}Tc-DISIDA$ and was compared with that from $^{99m}Tc-Phytate$ radionuclide angiogram. This study included 11 of normal subjects, 37 of intermediate group with various liver diseases, and 25 patients with liver cirrhosis. We analyzed the datas with slope method from radionuclide angiograms and the results were compared with hepatic arterial fractions from uptake method, introduced by Lee et al. at 1986. The hepatic arterial fractions from radionuclide angiograms using $^{99m}Tc-DISIDA$ and $^{99m}Tc-Phytate$ were $0.32{\pm}0.09\;and\;0.31{\pm}0.11$ respectively in normal subjects, and $0.75{\pm}0.18\;and\;0.77{\pm}0.21$ respectively in patients with liver cirrhosis. The hepatic arterial fractions by the slope method was well correlated with those of the uptake method on $^{99m}Tc-DISIDA$ scan. There was high correlation between the hepatic arterial fractions from $^{99m}Tc-DISIDA$ and $^{99m}Tc-Phytate$ scans. Hepatic arterial fraction estimated by the slope method is a useful index for the diagnosis of liver cirrhosis and the evaluation of status of portal hypertension.

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