• Korean Journal of Veterinary Research
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• v.15 no.2
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• pp.153-159
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• 1975

In order to investigate the effect of cobalt-60 gamma irradiation on the blood picture, the mice were subjected to single whole-body gamma irradiation externally. In this experiment 42 of 12 weeks old white mice were used and animals were allotted to group of three. On of chose groups served as control and the others as test groups that were exposed to single dose of 370 Rads (group I) and 500 Rads (group II). The exposure dose rate were averaged 33 Rads per Minute. The results obtained in this experiment were as follows: 1. Erythrocyte counts in both test groups dropped to the lowest level at 4 weeks postirradiation, returning towards the control level, but in recovery, group I showed rather prumpt compared with group II. Erythrocyte count in group II was significantly lower than that of group I. 2. Total leukocyte counts dropped to the lowest loved at 2 weeks postirradiation and group I recovered to normal level at 4 weeks postirradiation. Recovery group II was very slow and it reached to the control level on 12 weeks postirradiation. Leukocyte count was significantly different between group I and II. 3. Neutrophil count was increased to the highest level at 2 weeks postirradiation, with recovery to normal value after 8 weeks in group I and 12 weeks in group II, respectively. Neutrophil count was significantly different between group I and II. 4. Lymphocyte count dropped to the lowest level at 2 weeks postirradiation, with recovery to normal average after 8 weeks in group I and 12 weeks in group II, respectively. Lymphocyte count was significantly different between group I and II. 5. The other leukocyte count was increased after the irradiation and recovered at 12 weeks postirradiation in both test groups. The other leukocyte count was significantly different between group I and II.

• Korean Journal of Head & Neck Oncology
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• v.13 no.2
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• pp.251-255
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• 1997

Although primary surgical excision is the treatment of choice for the vast majority of patients with nasopharyngeal angiofibroma, radiation therapy is also employed as a primary tool or in the cases of tumor recurrence or massive intracranial extension. But, especially in young patients, postradiation sequelae such as osteomyelitis, atrophic rhinitis, thyroid or bone malignancy are of concern. Postirradiation osteosarcoma is a rare, but well-recognized complication of radiotherapy, which comprise roughly 2 to 5 percent of all osteogenic sarcoma. Recently we experienced a case of postirradiation osteosarcoma of the mandible who had treated by radiation therapy for the nasopharyngeal angiofibroma 30 years ago, presently he is ongoing chemotherapy and relatively being well.

• Radiation Oncology Journal
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• v.21 no.1
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• pp.66-74
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• 2003

Purpose : The matrix metalloprotelnases (MMPs) are a family of enzymes whose main function is the degradation of the extracellular matrix. Several studies have revealed that MMPs and TIMPS are related to the wound heating process and in photoaging caused by ultraviolet Irradiation. However, the expressions of MMP and TIMP after irradiation have not, to the best of our knowledge, been studied. This study investigates the expressions of MMP-2 and TIMP-2 in rat Intestinal mucosa following irradiation. Materials and Methods : The entire abdomen of Sprague-Dawley rats was irradiated using a single dose method. The rats were sacrificed on day 1, 2, 3, 5, 7 and 14 following irradiation. Histopathological observations were made using hematoxilin & eosin staining. The expressions of MMP-2 and TIMP-2 were examined using immunohistochemistry, Irnrnunoblotting and ELISA. Results : Radiation induced damage associated with atrophic villi, and infiltration of inflammatory cell was observed from the first postirradiation day, and severe tissue damage was observed on the second and the third postirradiation days. An increase in mitosis and the number of regenerating crypts, as evidence of regeneration, were most noticeable on the fifth postirradiation day. From the immunohistochemlstry, the MMP-2 expression was observed from the first postirradiation day, but was most conspicuous on the third and the fifth postirradiation days. The TIMP-2 expression was most conspicuous on the fifth postirradiation day. From the irnrnunoblotting, the MMP-2 expression was strongly positive on the third postirradlatlon day, and that of TIMP-2 showed a strong positive response on the fifth postirradiation day. In ELISA tests, the expressions of MMP-2 and TIMP-2 were increased in the postirradiation groups compared to those of the normal controls, and showed a maximum increase on the fifth postirradiatlon day. These results were statistically significant. Conclusion : The expressions of MMP-2 and TIMP-2 were increased in the intestinal mucosa of the rats following irradiation, and these results correlated with the histopathological findings, such as tissue damage and regeneration. Therefore, this study suggests that MMP-2 and TIMP-2 play roles in the mechanisms of radiation-induced damage and regeneration of intestinal mucosa of rats.

• Nuclear Engineering and Technology
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• v.50 no.6
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• pp.899-906
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• 2018

The irradiation performance of $U_3Si$ dispersion fuel in an Al matrix, $U_3Si-Al$, under the Hi-Flux Advanced Neutron Application Reactor (HANARO) design full-power condition of 30 MW was tested for full-power qualification of the fuel. A test assembly was fabricated containing 18 fuel rods made with atomized $U_3Si$ powder manufactured at the Korea Atomic Energy Research Institute. The test assembly was irradiated for 188 full-power operation days in the HANARO subject to the normal fuel-loading scheme and achieved about 60 at% U-235 average burnup and 75 at% U-235 peak burnup. The maximum linear power of the test assembly was 98 kW/m. Nondestructive and destructive postirradiation examinations were conducted. The measured postirradiation examination data were compared with data from previous irradiations and the design criteria required for HANARO fuel. Consequently, it was concluded that in-pile performance was acceptable and fuel integrity was maintained, and the behavior satisfied the fuel design requirements.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.262.1-262
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• 2002

• Radiation Oncology Journal
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• v.11 no.1
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• pp.17-27
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• 1993

To investigate the relationship between radiosensitivity and postirradiation recovery in human cancer cells, a study was performed using human cancer cell lines-A549, CaSki, SNU-C5 and PCI-13. For the study of radiosensitivity, single doses of 2, 4, 6, 8, 10, 12, and 14 Gy were given and for postirradiation recovery, two fractions of 4 Gy were separated with a time interval of 0, 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, or 6 hours. Surviving fraction was estimated using colony forming ability. Surviving fractions at 2 Gy (SF2) were 0.496 (0.570-0.412) for A549, 0.496 (0.660-0.332) for CaSki, 0.386 (0.576-0.216) for SNU-C5, and 0.185 (0.247-0.123) for PCI-13. By statistical analysis the SF2 of PCI-13 was lower significantly than those of others (p<0.05). This difference was also observed at 4, 6 and 8 Gy dose levels. At 6 and 8 Gy the surviving fractions of SNU-C5 were also lower significantly than A549 and CaSki (p<0.05). By the analysis with linear quadratic model, the values of ${\alpha}$ for A549, CaSki, SNU-C5 and PCI-13 were 0.3016, 0.3212, 0.4327 and 0.8423, respectively, and those of ${\beta}$ were 0.02429, 0.02009, 0.03349 and 0.00059, respectively. So, the value of ${\alpha}$ showed increasing tendency with decreasing SF2. By the multitarget single hit model the values of Do for A549, CaSki, SUN-C5 and PCI-13 were 1.97, 1.97, 1.46 and 0.81, respectively, and those of n were 1.53, 1.50, 1.56 and 2.28, respectively. So, the value of Do decreased with decreasing SF2. Post-irradiation recovery reached plateau at around 2 hours. Recovery ratio at plateau phase ranged from 1.2 to 4.2; the value were 1.2 for PCI-13, 3.2 for CaSki, 3.3 for SNU-C5, and 4.2 for A549. Recovery rate well correlated with SF2, and increased with increasing Do and decreasing ${\alpha}$. According to above results, the intrinsic radiosensitivity was quite different among the tested cell lines; PCI-13 was the most sensitive and A549 and CaSki was similar. This difference of radiosensitivity is thought to be partly due to the difference in amount of postirradiation recovery. By linear quadratic model the difference of ${\alpha}$ values was very high, and by multitarget single hit model the difference of Do value was significantly high among four cell lines.

• Korean Journal of Veterinary Research
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• v.13 no.1
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• pp.85-102
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• 1973

In the event a population of animals is exposed to ionizing radiation, proper disposition of animals will minimize loss to the farmer and protect the public from unwholesome meat and dairy products. Clinical response is an important factor in considering salvage of animals for food following exposure to ionizing radiation whether the dose is lethal or not. It is the purpose of this report to present the discussions of blood picture and growth of y ung growing rabbits exposed to cobalt-60 gamma-irradiation. The experimental animals were Hyrnalayan rabbits of 65 days old. The body weight for all animals of the time of irradiation was approximately 450g. The 96 rabbits used in the experiment were allotted t groups of eight. Rabbits in one group served as controls and the others were exposed to single doses of 100, 200, 300, 400, 500, 600 and 700 Roentgens (R). The exposure does rate averaged 15 R per minute. Central blood was obtained by heart puncture. Erythrocyte and leukocyte enumerations and, determinations of hemoglobin in blood and hematocrit value were made in the usual manner. Erythrocyte counts, concentrations of hemoglobin in blood, and hematocrit readings dropped to the lowest value between 1 and 4 weeks postirradiation, returning towards the control values. But recovery was not complete at the time of the last determination on 6 weeks postirradiation. There was a progressive decrease with increasing radiation does in the above values. Mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were not affected by the irradiation. After irradiation of each does the numbers of total leukocyte and the absolute numbers of various types of white cell began to decrease rapidly, and reached a minimum after 2 weeks, returning towards normal levels. But recovery was not complete at the time of the last determination on 6 weeks postirradiation. The reductions in total leukocyte and differential counts as the radiation does increases were apparent. Relative neutrophilia was observed in each irradiated group because of more expense of lymphocytes after irradiation. Growth rate of the rabbits was not affected by 100 R of whloe-body irradiation, while rabbits irradiated with 200, 300, 400 and 500 R showed marked depression of growth rate. As the radiation does increases, a depression of growth rate was apparent. The rabbits exposed to 600 and 700 R ceased from growing and recovery was not recognized during the experimental period.

• The Journal of the Korean dental association
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• v.18 no.8 s.137
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• pp.657-667
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• 1980

This study was undertaken to observe the salivary gland of the white rat when exposed to single and fractionated doses of Cobalt-60 irradiation. One hundred fifty white rats of the experiment were devided into control and 3 experimental groups. In experimental groups, group I receivcd 1200 rads everyweek untill 4800 rads reached, group II received 1500 rads and group III received 2000 rads with single dose. irradiation was carried out using a RAC-120 Cobalt-60 Teletherapy Unit with a dose rate 84.3 r/min, field size 4×5 cm measured at 80 from source. Rats were serially sacrificed at the following postirradiation time intervals: 1, 3, 5, 7, 10, 14, 21, 28, 35, and 42days. At sacrifice, the parotid and submandibular glands were dissected out in toto, and stained with: 1) hematoxylin and eosin; 2) periodic acid Shiff; 3) toludine blue.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1987.05a
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• pp.19.2-19
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• 1987

방사선치료후 재발성 또는 잔존성 두경부암의 수술후에 피부판의 괴사 및 slough, 감염, 누공, 부종과 경동맥 노출 심지어는 경동맥 파열 등의 술후 합병증이 빈발함으로 수술에 큰 어려움을 겪게 된다. Pectoralis major myocutaneous flap은 진행된 두경부암의 광범위한 절제후에 그 결손부를 보충해 주는 데 좋은 방법으로 사용할 수 있을 뿐아니라 방사선치료후에 생긴 합병증에도 이 flap을 이용하여 좋은 치료결과를 얻을 수 있다. 저자들은 수술 전에 방사선치료를 받고 심한 부종으로 후두조직의 괴사 및 기능이 손실된 환자와 방사선 치료후 재발된 상인두암환자의 경우에서 수술 후 생긴 pharyngocutaneous fistula와 피부판감염 및 경동맥노출 등으로 치유가 곤란하여 여기에 pectoralis major myocutaneous flap을 사용하여 pharyngostoma를 재건하고 노출된 경동맥부위를 보호하여 좋은 치료효과를 얻었기에 문헌을 고찰하여 보고하는 바이다.

• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.14-25
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• 1992

Thallium-201 $(^{201}T1)$ SPECT studies were performed on a normal volunteer and 12 patients with intracerebral lesions: 3 patients with gliomas, 3 patients with meningiomas, 1 patient each with metastatic tumor, brain abscess, and cerebral infarction, and 3 postirradiation patients. (2 with metastatic tumors, 1 with lymphoma). A $^{201}T1$ index, based on the ratio of $^{201}T1$ uptake in the brain lesion versus the homologous contralateral brain, was calculated and compared with tumor histology and CT/MRI findings. The SPECT $^{201}T1$ scan showed minimal uptake of tracer in a normal brain. There was substantial uptake of $^{201}T1$ in high-grade gliomas (index>1.5) with little uptake in low-grade lesions. A previously irradiated patient with recurrent astrocytoma, in whom MRI study was unable to distinguish tumor recurrence from necrosis, showed the lesions with high $^{201}T1$ indices in both hemispheric regions (2.50/1.93), suggesting tumor recurrence. Two meningiomas and a metastatic tumor showed varying degrees of $^{201}T1$ uptake (index $1.71\sim8.15$), revealing that $^{201}T1$ uptake is not exclusive to high-grade gliomas. In 2 postirradiation patients with metastatic tumors, no abnormal $^{201}T1$ uptake was found in the cerebral lesions, shortly after the initiation of radiation therapy or despite the persistence of enhancing lesions-though improved-on MR images, suggesting that $^{201}T1$ uptake may reflect the metabolic and possibly clonogenic activities of tumors and the brain $^{201}T1$ SPECT imaging might be valuable for the evaluation of tumor responsiveness to the therapy and for early detection of tumor recurrence. A patient with brain abscess on antibiotic treatment, showig increased uptake of $^{201}T1$ in the resolving lesions (index 2.87/1.52) is discussed. In a patient with cerebral infarction, there was no abnormal uptake of $^{201}T1$ in infarcted tissue. When using a threshold index of 1.5, correlation rate between $^{201}T1$ uptake and contrast enhancement of the cerebral lesions on CT/MRI was 73% (8/11). In conclusion, the brain $^{201}T1$ SPECT imaging may be useful for assessment of tumor response to the therapy and to predict low-or high-grade lesions.