• Journal of Radiation Protection and Research
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• 제28권4호
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• pp.299-309
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• 2003

동적 섭식경로모델 DYNACON을 개선하여 원자력시설의 사고시 환경으로 누출된 방사성물질에 의한 가축의 공기 흡입과 토양 섭취에 따른 축산물의 오염 영향을 고찰하였다. 이들 두 오염경로에 대한 수학적 모델은 고려되는 모든 축산물에 대해 수립되었지만 결과에 대한 상세 고찰은 우유에 국한하였다. 젖소의 공기 흡입과 토양 섭취는 방사성물질의 환경 누출이 목초가 성장하지 않는 비방목 기간에 일어나는 경우에 우유의 중요한 오염경로가 될 수 있다는 사실을 알 수 있었다. 비방목 기간동안 방사성물질이 환경으로 누출되는_경우 초기에는 공기 흡입이 토양 섭취에 의한 영향보다 높으나, 시간이 경과할수록 토양 섭취가 우유의 오염에 있어서 지배적 영향을 미쳤다. 이러한 현상은 전반적으로 지상으로 상대적으로 많은 침적을 일어나게 하는 누출기간 중 강우가 있는 경우에 보다 뚜렷하였다. $^{137}Cs$과 $^{90}Sr$의 경우와 달리 $^{131}I$은 누출기간 중 강우에 거의 영향을 받지 않았다. 방목기간에 방사성물질이 환경으로 누출되는 경우 누출기간 중 강우의 유무에 관계없이 공기 흡입에 의한 우유의 오염 영향은 무시 가능한 수준이었다.

• Journal of Radiation Protection and Research
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• 제42권2호
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• pp.114-129
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• 2017

Background: The purpose of this paper is to confirm the event timings and the magnitude of fission product aerosol release from the Fukushima accident. Over a few hundreds of technical papers have been published on the environmental impact of Fukushima Daiichi accident since the accident occurred on March 11, 2011. However, most of the research used reverse or inverse method based on the monitoring of activities in the remote places and only few papers attempted to estimate the release of fission products from individual reactor core or from individual spent fuel pool. Severe accident analysis code can be used to estimate the radioactive release from which reactor core and from which radionuclide the peaks in monitoring points can be generated. Materials and Methods: The basic material used for this study are the initial core inventory obtained from the report JAEA-Data/Code 2012-018 and the given accident scenarios provided by Japanese Government or Tokyo Electric Power Company (TEPCO) in official reports. In this research a forward method using severe accident progression code is used as it might be useful for justifying the results of reverse or inverse method or vice versa. Results and Discussion: The release timing and amounts to the environment are estimated for volatile radioactive fission products such as noble gases, cesium, iodine, and tellurium up to 184 hours (about 7.7 days) after earthquake occurs. The in-plant fission product behaviors and release characteristics to environment are estimated using the severe accident progression analysis code, MELCOR, for Fukushima Daiichi accident. These results are compared with other research results which are summarized in UNSCEAR 2013 Report and other technical papers. Also it may provide the physically based arguments for justifying or suspecting the rationale for the scenarios provided in open literature. Conclusion: The estimated results by MELCOR code simulation of this study indicate that the release amount of volatile fission products to environment from Units 1, 2, and 3 cores is well within the range estimated by the reverse or inverse method, which are summarized in UNSCEAR 2013 report. But this does not necessarily mean that these two approaches are consistent.

• Journal of Radiation Protection and Research
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• 제44권3호
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• pp.118-126
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• 2019

Background: Government conducts environmental radioactivity surveillance for verification purpose around nuclear facilities based on the Nuclear Safety Law and issues a surveillance report every year. This study aims to evaluate the short and the long-term fluctuation of radionuclides detected above MDC and their origins using concentration ratios between these radionuclides. Materials and Methods: Sample media for verification surveillance are air, rainwater, groundwater, soil, and milk for terrestrial samples, and seawater, marine sediment, fish, and seaweed for marine samples. Gamma-emitting radionuclides including $^{137}Cs$, $^{90}Sr$, Pu, $^3H$, and $^{14}C$ are evaluated in these samples. Results and Discussion: According to the result of the environmental radioactivity verification surveillance in the vicinity of nuclear power facilities in 2017, the anthropogenic radionuclides were not detected in most of the environmental samples except for the detection of a trace level of $^{137}Cs$, $^{90}Sr$, Pu, and $^{131}I$ in some samples. Radioactivity concentration ratios between the anthropogenic radionuclides ($^{137}Cs/^{90}Sr$, $^{137}Cs/^{239+240}Pu$, $^{90}Sr/^{239+240}Pu$) were similar to those reported in the environmental samples, which were affected by the global fallout of the past nuclear weapon test, and Pu atomic ratios ($^{240}Pu/^{239}Pu$) in the terrestrial sample and marine sample showed significant differences due to the different input pathway and the Pu source. Radioactive iodine ($^{131}I$) was detected at the range of < $5.6-190mBq{\cdot}kg-fresh^{-1}$ in the gulfweed and sea trumpet collected from the area of Kori and Wolsong intake and discharge. A high level of $^3H$ was observed in the air (Sangbong: $0.688{\pm}0.841Bq{\cdot}m^{-3}$) and the precipitation (Meteorology Post: $199{\pm}126Bq{\cdot}L^{-1}$) samples of the Wolsong nuclear power plant (NPP). $^3H$ concentration in the precipitation and pine needle samples showed typical variation pattern with the distance and the wind direction from the stack due to the gaseous release of $^3H$ in Wolsong NPP. Conclusion: Except for the detection of a trace level of $^{137}Cs$, $^{90}Sr$, Pu, and $^{131}I$ in some samples, anthropogenic radionuclides were below MDC in most of the environmental samples. Overall, no unusual radionuclides and abnormal concentration were detected in the 2017's surveillance result for verification. This research will be available in the assessment of environment around nuclear facilities in the event of radioactive material release.

• 대한두경부종양학회지
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• 제23권1호
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• pp.50-53
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• 2007

Adrenal metastasis from papillary thyroid carcinoma is extremely rare. We present herein a patient with adrenal metastases from recurrent papillary carcinoma of the thyroid. A 54 year-old woman had received a total thyroidectomy and postoperative radioactive iodine therapy for locally advanced papillary thyroid carcinoma. One year after initial surgery, distant metastases to multiple organs including right cervical lymph nodes, left upper lung, left 2nd and 3rd ribs, 2nd thoracic vertebra and left adrenal gland were found by 18-FDG-PET-CT whole body scan. She underwent right modified neck dissection, partial resection of left 2nd and 3rd ribs, posterior arch of 2nd thoracic vertebra, left upper lobectomy of lung, and left adrenalectomy. On histologic examination, metastases to the left adrenal gland and cervical lymph nodes were papillary thyroid carcinomas, while other metastatic sites turned out to be anaplastic thyroid carcinomas. Despite aggressive surgery and postoperative adjuvant therapy, her general clinical conditions were getting worse day by day due to regrowing of the anaplastic thyroid carcinomas. To our knowledge, this is the first case reported in Korea.

• 대한핵의학회지
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• 제9권2호
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• pp.1-11
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• 1975

The serum concentrations of thyrotropin (TSH) were measured by means of radioimmunoassay, in 98 cases of normal controls, 51 cases of hyperthyroidism, 80 cases of primary hypothyroidism and 4 cases of secondary hypothyroidism to evaluate the diagnostic significance in various functional states of the thyroid. The obtained data were analyzed in correlation with other thyroid function test values in various phases of the functional thyroid diseases. The results were as follows: 1) The serum TSH concentration in normal control group was $<1.3{\sim}8.0{\mu}U/ml$. 2) The measurement of serum TSH was more significant in diagnostic accuracy compared with that of serum $T_4(75.0{\pm}12.2%)$. Free $T_4$ Index ($64.2{\pm}15.2%$), serum $T_3(41.0{\pm}21.0%)\;or\;T_3$ resin uptake ($41.1{\pm}15.8%$) in evaluation of primary hypothyroidism. 3) In case of overt hypothyroidism, the serum TSH and $T_4$ were both abnormal, compatible with the clinical diagnosis, while in case of preclinical or mild hypothyroidism, the serum $T_4(41.2{\pm}23.8%)\;or\;50.0{\pm}25.0%)$ was much less reliable than serum TSH. 4) In the treatment of primary hypothyroidism with desiccated thyroid, the administration of 1 grain of the hormone per day was sufficient to suppress the serum concentration of TSH to normal range. It showed that the measurement of serum TSH concentration was a significant criteria in evaluating the efficiency of the treatment of hypothyroidism. 5) The measurement of serum TSH concentration is a very significant method in the early detection of hypothyroidism induced during or after the treatment of the hyperthyroidism with antithyroid drugs or radioactive Iodine ($^{131}I$).

• Journal of Korean Neurosurgical Society
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• 제30권1호
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• pp.89-94
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• 2001

Skull or brain metastasis from thyroid carcinoma is rare. Between Jan. 1993. and Jan. 2000. the authors experienced 7 cases of skull(4 cases) or brain(3 cases) metastasis from thyroid carcinoma. Clinical characteristics, radiologic findings and pathologic features were analyzed retrospectively. Among 4 cases of skull metastasis, 3 cases were follicular carcinoma and one was papillary carcinoma with follicular variant. All cases of brain metastasis were papillary carcinoma. We treated the patients by combination with surgical resection, radioactive iodine therapy and radiation therapy. Characteristics of skull or brain metastasis from thyroid carcinoma is reviewed with a pertinent literature.

• 대한핵의학회지
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• 제16권2호
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• pp.1-24
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• 1982

Several recent advances in our knowledge of thyroid physiology have broad application to the diagnosis and management of thyroid disorders. For in the thyroid, more than other endocrine organs, pathophysiology can be translated directly into the diagnosis and management of thyroid disease. Graves' disease is a syndrome including goiter with hyperthyroidism, exophthalmos and dermopathy. The pathogenesis of Graves' disease is not yet clearly identified, but various autoantibodies to the thyroid gland and immunopathologic studies indicate that autoimmune processes are involved in the pathogenesis of the disease. The diagnosis and management of Graves' disease are largely dependent on radionuclide techniques as radioimmunoassay, radioactive iodine therapy and so on. Several laboratory tests are also developed to determine the remission of this disase including TRH stimulation test, $T_3$ suppression test and detection of thyroid stimulating immunoglobulins. Autoimmune thyroiditis is almost certainly a primary immunologic disease and the incidence tends to increase recently, mainly due to the application of biopsy technique in thyroid diseases. Thyroid nodules have been a great challenge to physicians because of the possibility of malignancy. But recently, cytologic examination of thyroid aspirate provides a very simple and also reliable diagnostic method in patients with thyroid nodules. In 163 patients with thyroid nodules, only 19.3% was revealed to be malignant. Therefore cytologic examination of thyroid aspirate and thyroid biopsy should be included in the diagnosis of nodular patients prior to surgical intervention. In this paper, a comprehensive review is presented on the pathogenesis, clinical features, laboratory findings and therapeutic modalities of various thyroid diseases on the basis of over 80 researches performed during the past 20 years at radioisotope clinic, Seoul National University Hospital.

• 분석과학
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• 제16권2호
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• pp.110-116
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• 2003

사용 후 핵연료의 화학특성 연구를 위하여 요오드의 분리와 정량에 관한 연구를 수행하였다. 사용 후 핵연료를 용해시키는 과정에서 핵연료 중에 CsI로 존재하는 요오드가 $I_2$로 산화되어 휘발되지 않도록 질산과 염산의 혼합산 (80:20 mol%)을 이용하여 비휘발성 ${IO_3}^-$­로 안정화시켰다. 2.5 M $HNO_3$ 매질에서 $NH_2OH{\cdot}HCl$을 이용하여 $I_2$로 환원시킨 후 사염화탄소로 추출하여 우라늄과 핵분열생성물로부터 분리, 회수하였다. 0.1 M $NaHSO_3$을 사용하여 요오드를 역추출하였으며 수용액층으로 회수된 요오드를 이온 크로마토그래피로 정량하였다. 방사성 물질 분석에 적합한 이온 크로마토그래피/차폐 시스템을 구성하였으며 42,000~44,000 MWd/MtU 의 연소도를 갖는 사용후핵연료를 대상으로 요오드를 분석한 결과 Origin 2 연소도 전산코드에 의한 계산결과인 $324.5{\sim}343.6{\mu}g/g$와는 -8.3~-0.5%의 편차를 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.1001-1010
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• 2005

Bacillus megaterium KL39, an antibiotic-producing plant growth promoting rhizobacterium (PGPR), was selected from soil. The antifungal antibiotic, denoted KL39, was purified from culture filtrate by column chromatography using Dion HP-20, Silica gel, Sephadex LH-20, and prep-HPLC. Thin layer chromatography, employing the solvent system of ethanol:ammonia:water=8:1:1, showed the $R_{f}$. value of 0.32. The antibiotic KL39 showed a negative reaction with ninhydrin solution, positive with iodine vapor, and also positive with Ehrlich reagent. It was soluble in methanol, ethanol, butanol, and acetonitrile, but insoluble in chloroform, toluene, hexane, ethyl ether, or acetone. Its UV spectrum had the maximum absorption at 208 nm. Amino acid composition, FAB-mass, $^{1}H-NMR,\;^{13}C-NMR$, and atomic analyses showed that the antibiotic KL39 (MW=1,071) has a structure very similar to iturin E. The antibiotic KL39 has a broad antifungal spectrum against a variety of plant pathogenic fungi including Rhizoctonia solani, Pyricularia oryzae, Monilinia froeticola, Botrytis cinenea, Altenaria kikuchiana, Fusarium oxysporum, and F. solani. An MIC value of $10\;{\mu}g/ml$ was determined for Phytophthora capsici. Macromolecular incorporation studies with P. capsici using radioactive [$^{3}H-adenine$] as the precursor, indicated that the antibiotic KL39 strongly inhibits the DNA biosynthesis of the fungal cell. Microscopic observation of the antifungal action showed abnormal hyphal swelling of P. capsici. The purified antibiotic KL39 was very effective for the biocontrol of in vivo Phytophthora-blight disease of pepper.

• 대한수의학회지
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• 제6권1호
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• pp.24-30
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• 1966

In order to observe the effect of the injected radioactive iodine-$I^{131}$ on the uptake in thyroid of normal male guinea pigs and P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum, 24 matured male guinea pigs were divided in 4 groups and $35{\mu}c$, $70{\mu}c$, $140{\mu}c$ and $280{\mu}c$ per kg of body weight respectively were injected subcutaneously. 1. The uptake rates of radioactveiodine-$I^{131}$ by external counts of thyroidal uptake reached the maximum level of uptake in 24 hours after injection. 2. As the injected amount increases, the uptake rates of maximum levels and release rate were increased. 3. Uptake rate in the removed thyroid have shown no statistical in the $35{\mu}c$ and $70{\mu}c$ groups of injected guinea pigs. 4. There was no statistical significance in $140{\mu}c$ and $280{\mu}c$ groups of injected guinea pigs. 5. P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum was not in proportion to injected amounts: 61.0%(35), 70.2%(70), 75.3%(140) and 64.8%(280).