• Radiation Oncology Journal
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• v.4 no.1
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• pp.15-20
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• 1986

From 1979 to 1984, 39 local allograft irradiations were given to 29 patients: 10 irradiations were administered for prevention and 29 for reversal of acute rejection of transplanted kidney. Three doses of 150 cGy every other day were combined with high-dose of methylprednisolone pulse (1 gm/day) for 3 days. For prevention of acute rejection, local irradiation was delivered on the days 1, 3, and 5 after the transplantation, and for reversal, irradiation started after the diagnosis of acute rejection. Eight out of 10 patients irradiated for prevention had acute allograft rejection, and, what is more, there was no surviving graft at 15 months after transplantation. Reversal of acute rejection was achieved in $71\%$. When the pre-irradiation level of serum creatinine was below $5.5mg\%$, the reversal rate was $93\%$, but above $5.5mg\%$ the reversal rate was only $17\%$ (p<0.01). Reirradiation after failure was not successful. Among 15 reversed patients, $7(47\%)$ had subsequent rejection (s). The functional graft survivals at 6 month, 1, 2, and 3 year were $70\%,\;65\%,\; 54\%,\;and\;54\%$, respectively. Therapeutic irradiation resulted in better graft survival when serum creatinine was below $5.5mg\%$ (p<0.001) or when irradiation started within 15 days after the diagnosis of acute rejection (p<0.001).

• Imaging Science in Dentistry
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• v.36 no.1
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• pp.7-15
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• 2006

Purpose : To investigate the caspase-3 expression in the acinar and ductal cells of rat submandibular glands after the irradiation of various doses. Materials and Methods : The male Sprague-Dawley rats weighing approximately 250 gm were used for this study. The experimental group was irradiated with a single absorbed dose of 2, 5, 10, and 15 Gy on the head and neck region. The rats were sacrificed on the 1st, 3rd, 7th, 14th, 21 st, and 28th day after irradiation. The specimens including the submandibular gland were sectioned and observed using histopathological and immunohistochemical methods. Results : The local destruction of the acinar and ductal cells and the karyopyknotic nuclei of the acinar cells were observed in the 2 Gy and 5 Gy irradiation groups later than in the 10 Gy and 15 Gy irradiation groups. And the expression of caspase-3 was prominent only in the ductal cells in the 2 Gy and 5 Gy irradiation groups. Conclusion : This experiment suggests that radiation-induced apoptosis in the ductal cells of rat submandibular glands was induced by a low dose radiation associated with the activation of caspase-3 and radiation-induced necrosis was induced by a high dose radiation.

• Radiation Oncology Journal
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• v.6 no.2
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• pp.289-293
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• 1988

Radiation therapy has been used as adjuvant therapy or primary treatment for inoperable, remnant or recurrent cancer. Many authors reported good palliation effect by external irradiation or interstitial therapy, but the report of intracavitary irradiation for recurrent, inoperable rectal cancer is very rare. We experienced a case of recurrent adenocarcinoma of rectum along fistula tract after laparotomy and postoperative radiotherapy who achieved very good palliation by intracavitary irradiation. Even though we have only good palliation without impressive survival improvement in this case, we hope that this technique may achieve good local control In other similar patients.

• Radiation Oncology Journal
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• v.5 no.2
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• pp.173-176
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• 1987

Carcinoma of extrahepatic biliary tract is slow growing tumor but curative resection is rarely successful. Radiation therapy has been introduced for enhancing palliation and possible longterm survival. We treated a case of advanced extrahepatic biliary tract carcinoma with high dose rate remote afterloading system through T-tube as a initial irradiation postoperatively. We hope that this treatment may affect not only ennancing palliation and better quality of life but also in local tumor control.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3747-3750
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• 2013

Purpose: To evaluate the efficacy of conservative surgery plus chemo-, radio-therapy in treating patients with early stage breast cancer. Patients and Methods: Eligible patients were treated by postoperative chemotherapy as well as whole-breast irradiation with tumor bed boost. Postoperative radiotherapy consisted of 6 MV whole breast linear accelerator irradiation with two tangential half fields to a total dose of 45~50 Gy, followed by $10{\sim}15MeV{\beta}$ boost irradiation to tumor bed for 10~20Gy, total dose 56~66Gy. Results: Fifty-two patients were enrolled. Overall 1-, 2- and 3 year survival rates were 98.1%, 92.3%, and 90.4%, respectively, with a local recurrence rate of 5.77%. Cosmetic results were evaluated as good by doctors in 90.4% of patients. Conclusions: Breast conservative surgery combined with chemo- radio-therapy could be a treatment option for Chinese patients with early stage breast cancer.

• Radiation Oncology Journal
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• v.1 no.1
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• pp.103-109
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• 1983

47 out of 56 cases of intact uterine cervix cancer treated by radiation at the Hanyang University Hospital were followed 18 months or more after treatment. (7 patients died before 18 months, 2 cases lost to follow-up). Age distribution reveal 5 cases in 30's, 18 cases in 40's, 17 cases in 50's, 7 cases in 60's. Histologically, all cases were squamous cell type except one case of adenocarcinoma. 1. 45 cases were treated by combined external Co-60 irradiation and intracavitary irradiation by Cs-137 small sources. 1 case was treated by external irradiation only, and 1 case by intracavitary only. 2. Rectal injuries were observed in 13 cased (27.6%), 4 cases in Grade 1, 8 cased in Grade 2 and 1 cases in Grade 3 which needed surgical management. 3. Average intervals of rectal injury following treatment was 9.2 months varying from 5 to 15 months. 4. Relation between rectal injury and point A dose reveal 6 cases between 7000-7999 rad and 6 cases between 8000-8999 rad and 1 case above 9000 rad. Even though there is no direct relation between point A dose and rectal injury, it is expected that rectal injury increases as point A dose increase. 5. In the normal condition, rectal injury can't be attributed to one major cause. Radiation dose, small source distribution, general condition of patients, local anatomy of the individual patient, history of PID and previous surgery, all play complex roles.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.625-626
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• 2008

The magnetic domain-refining techniques such as ball scratching, laser irradiation and plasma have been developed to reduce the domain wall spacing and thus iron losses in Fe-3%Si grain-oriented silicon steels. In view point of magnetic properties, it was supposed that the locally residual stresses change the magnetoelastic energy of the material and thus the spacing between $180^{\circ}$ domain walls decreases in order to reduce the magnetostatic energy. The effect of laser irradiation on iron loss and magnetostriction reduction for Fe-3%Si grain-oriented steel were investigated. Since the local tensile stresses were induced at the surface of Fe-3%Si steel by the laser irradiation, the minimum iron loss caused by reducing eddy current loss was obtained in spiete of the decrease of permeability by hindering eddy current loss was obtained in spite of the decrease of permeability by hindering the domain wall movement around the induced stress field. Furthermore, the laser treated 3%Si steel has lower magnetostriction as compared to non laser-treated steel and is less sensitive to applying pre-stresses due to the volume reduction of $90^{\circ}$ domain in materials.

• Laser Solutions
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• v.4 no.2
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• pp.21-28
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• 2001

The laser strengthening of 35kgf/㎟ and 60kgf/㎟ grade steel sheets is investigated by using CO$_2$ laser beam irradiation. The increase of tensile strength is dominated by the number of fully penetrated melting line. Also. the optimal laser input energy(hardness) and the number of melting line (melting width) are important variables for laser strengthening. Local strengthening by laser beam may be effective for the weight reduction of components where the tailored welded blank can not be applied.

• Radiation Oncology Journal
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• v.37 no.1
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• pp.1-12
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• 2019

Despite recent innovation in treatment techniques and subsequently improved outcomes, the majority of glioblastoma (GBL) have relapses, especially in locoregional areas. Local re-irradiation (re-RT) has been established as a feasible option for recurrent GBL of all ages with safety, tolerability, and effectiveness both in survival and quality of life regardless of fractionation schedule. To keep adverse effects under acceptable range, cumulative dose limit in equivalent dose at 2 Gy fractions by the linear-quadratic model at α/β = 2 for normal brain tissue (EQD2) with narrow margin should be observed and single/hypofractionated re-RT should be undertaken very carefully to recurrent tumor with large volume or adjacent to the brainstem. Promising outcome of re-operation (re-Op) plus re-RT (re-Op/RT) need to be validated and result from re-RT with temozolomide/bevacizumab (TMZ/BV) or new strategy is expected. Development of new-concept prognostic scoring or risk group is required to select patients properly and make use of predictive biomarkers such as O(6)-methylguanine-DNA methyltransferase (MGMT) promotor methylation that influence outcomes of re-RT, re-Op/RT, or re-RT with TMZ/BV.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.271-275
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• 2004

A fast switching thyristor with a superior trade-off property between the on-state voltage drop and the turn-off time could be fabricated by the proton irradiation method. After fabricating symmetric thyristor dies with a voltage rating of 1,600V from $350{\mu}m$ thickness of $60{\Omega}cm$ NTD-Si wafer and $200{\mu}m$ width of N-base drift layer, the local carrier lifetime control by the proton irradiation was performed with help of the HI-13 tandem accelerator in China. The thyristor samples irradiated with 4.7MeV proton beam showed a superior trade-off relationship of $V_{TM}=1.55V\;and\;t_q=15{\mu}s$ attributed to a very narrow layer of short carrier lifetime(${\sim}1{\mu}s$) in the middle of its N-base drift region. To explain the small increase of $V_{TM}$, we will introduce the effect of carrier compensation by the diffusion current at the low carrier lifetime region.