• 환경생물
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• 제17권1호
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• pp.21-26
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• 1999

살충제와 방사선이 자주달개비 수술털 돌연변이에 미치는 복합적 영향을 평가하였다. 포트에서 생육된 Tradescantia 4430 식물체에 코발트 선원으로부터 0.3, 0.5, 1.0 및 2.0 Gy의 감마선을 조사하였다. 살충제는 감마선 조사 24시간 전에 농업용으로 사용되는 파라치온 유제를 살포하였다. CT 실험군과 Pa+${\gamma}$실험군에 있어서의 돌연변이 빈도가 증가한 고조기간은 방사선 조사 후 7 ~ 11일로 돌연변이 빈도는 방사선량 증가에 따라 선형적으로 증가하는 반응관계를 보였다. CT 실험군에서의 선량반응식 기울기 (증가계수)는 5.99 ($r^2$=0.988)이었으나, Pa+${\gamma}$ 실험군의 증가계수는 3.43 (r$x^-2$=0.981)으로 CT 실험군의 값에 비해 현격히 낮았다. 즉 Pa+${\gamma}$ 실험군이 CT 조사군에 비하여 방사선에 의한 돌연변이 유발 증가율이 43%억제됨을 확인할 수 있었으며 이는 살충제 전처리가 방사선에 의한 세포유전물질 손상을 오히려 저감시키는 효과를 나타낸 것이기 때문이다. 이 같은 실험결과는 두 가지 불리한 자극이 복합적으로 작용할 때 일반적으로 나타나는 공조작용과는 상반되는 결과이며 오히려 파라치온 전처리에 의해 식물체가 보다 강한 자극에 대비할 수 있도록 유도되는 적응반응이 유발되었거나 방사선효과에 대한 변화작용이 나타난 것으로 해석 가능하다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권6호
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• pp.379-391
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• 2003

The present study was undertaken to evaluate bone regenerative capacity around titanium screw implants placed in irradiated rat's tibiae. At one week after single 15-Gy dose irradiation, miniaturized titanium screw implants were inserted into anterior aspect of the upper tibia of rats weighing 200-250g. Seventy rats were involved: 35 rats were control and 35 rats radiation group. The rats were killed at different intervals as 1, 2, 3, 4, 6, 8, 12 weeks after implantation for histologic observation, histomorphometric analysis and immunohistochemical study with fibronectin and CD34 antibody. 1. Histologically, various stages of bone maturation and ossification can be seen at 4 weeks and regenerated bone close to edges demonstrates more advanced calcification, and network of new bone are well formed at 12 weeks in non-irradiated group. In contrast, active bone formation with increased contact of newly formed bone to implant surface was noted at 4 weeks and a significant amount of new bone formation and bone-implant contact is oberved at 12 weeks in irradiated group. 2. Histomorphometrical analysis confirmed these histologic findings. A significant difference in implant-bone contact and bone density was measured between the control and radiation group. Mean MBD was 62.2% in control group and 27.5% in radiation group, mean MBIC was 86.6% in control group and 47.7% in radiation group, and mean TBIC was 87.3% in control group and 45.6% in radiation group at 12 weeks after implantation. 3. In immunohistochemical study with fibronectin and CD34, radiation reduced hematopoietic progenitor cells severely and disturbed differentiation of osteoblast in bone marrow. The results of this study revealed bone healing capacity around implant after radiation therapy was severely impaired and irradiation reduces the capacity for osseointegration of titanium implants. Many factors including radiation dose, period between radiation and implantation, bone quality, time elapse between first and second surgery, type of prosthetics and hyperbaric oxygen therapy must be considered carefully in postradiation implantation.

• 한국양식학회지
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• 제19권3호
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• pp.166-172
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• 2006

동일 종내 미꾸라지(Misgurnus mizolepis) 웅성발생성 인공처녀생식(intraspecific androgenesis)기술을 개발하기 위해 미꾸라지 난 유전물질의 불활성화와 이에 따른 웅성발생성 반수체 유도 조건을 최적화하였다. 다양한 자외선(UV)농도$(0\sim25,650ergs/mm^2)$를 이용하여 미꾸라지 난의 유전학적 불활성화를 시도하였으며 수정률, 부화율 및 반수체 출현율을 평가한 결과 10,800 ergs의 농도에서 가장 우수한 반수체 유도 효율을 보였으며 최초 처리 난 중 50%이상의 웅성발생성 반수체 수율을 확보할 수 있었다. 웅성발생성 개체는 전형적인 haploid syndrome의 특징을 나타내었고 flow cytometry분석 결과 정확히 미꾸라지 반수체(1.4 pg/cell)의 DNA함량을 보유하는 것으로 나타났다. 인위적으로 삽입된 형질전환 유전자 표지를 이용하여 부계 특이적인 인공처녀생식 여부를 확인하였으나 일부 반수체자어들에서$(8\sim11%)$ 모계 유전물질의 잔류가 검출되었다.

• Radiation Oncology Journal
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• 제13권2호
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• pp.113-120
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• 1995

Purpose : To investigate the effect of alkaloid fraction from Korean ginseng on radiation-induced DNA double strand breaks (dsb) formation and repair in murine lymphocytes Materials and Methods : We used the neutral filter elution technique to assay $^{60}Co\;{\gamma}$ ray-induced DNA double strand breaks formation and repair in C57BL/6 mouse spleen lymphocytes for evaluating the dose-response relationship in the presence of alkaloid fraction as a radioprotective agent. The lymphocytes were stimulated with Phytohemagglutinin (PHA, 2 u g/ml) to label $^3[H]-thymidine.$ Isotope-labelled lymphocytes in suspension were exposed to 100 Gy at $0^{\cdot}C$ in the alkaloid fraction-treated group and elution procedure was performed at PH 9.6. The extents of formation of radiation-induced DNA double strand breaks and repair were compared respectively via strand scission factor (SSF) and relative strand scission factor (RSSF). Results: Alkaloid fraction reduced the formation of double strand breaks with dose modification factor of 2 15, compared to control group Rejoining of DNA dsb appeared to take place via two components. The first fast component was completed within 20.4 minutes, but the second slow component was not completed until 220.2 minutes after irradiation. About $30\%$ of dsb formed by irradiation was ultimately unrejoined despite the administration of alkaloid fraction. The administration of alkaloid fraction had a great effect on the second slow component of repair; the half-time of fast component repair was not changed, but that of slow component was 621.8 minutes. Conclusion: Neutral filter elution assay Proved to be a very effective method to quantitate the extents of DNA dsb formation and its repair. By using this technique, we were able to evaluate the efficiency of alkaloid fraction from Korean ginseng as a valuable radioprotector. Alkaloid fraction can be used prophylactically to prevent or ameliorate the severe radiation damages in workers and neighbors around the atomic power plants. For more refined study, however, more advanced purification of alkaloid fraction wil be needed in the near future.

• Radiation Oncology Journal
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• 제13권3호
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• pp.233-241
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• 1995

Purpose : To analyse clinical outcome and prognostic factors according to treatment modality, this paper report our experience of retrospective study of patients with esophageal cancer Materials and Methods : One hundred and ten patients with primary esophageal cancer who were treated in Presbyterian Medical Center from May 1985 to December 1992. We analysed these patients retrospectively with median follow up time of 28 months, one hundred and four patients($95{\%}$) were followed up from 15 to 69 months. In methods, twenty-eight patients were treated with median radiation dose irradiated 54.3Gy only. Fifty-six patients were treated with combined chemoradiotherapy. Sixteen cases of these patients were treated with concurrent chemoradiation and the other patients(forty cases) were treated sequential chemoradiotherapy. In concurrent chemoradiotherapy group, patients received 5-FU continuous IV infusion for 4 days. Cisplatin IV bolus. and concurrent esophageal irradiation to 30 Gy. After that patients received 5-FU continuous IV, Cisplatin bolus injection and Mitomycin-C bolus IV, Bleomycin continuous IV, and irradiation to 20 Gy. In sequential chemoradiotherapy group, the chemotherapy consisted of 5-FU 1,000mg/$m^2$ administered as a continuous 24 hour intravenous infusion during five days and Cisplatin 80-100mg/$m^2$ bolus injected, or Bleomycin, Vinblastine, Cisplatin, Methotrexate were used of 1 or 2 cycles. After preoperative concurrentm chemoradiation twenty-six patients underwent radical esophagectomy. Results : Ninety-three patients could be examined for response assessment, By treatment modality, response rates were $85.1{\%}$ for radiation alone group and $86.3{\%}$ for combined chemoradiation group. But in operation group, after one cycle of concurrent chemoradiation treatment, response rate was $61.9{\%}$. The pathologic complete response were $15.4{\%}$ in operation group. Overall median survival was II months and actuarial 5-year survival rate was $8{\%}$. The median survival interval was 6 months for radiation alone group, 11 months for combined chemoradiation group and 19 months for operation group. And also median survival was 19 months for complete responder group that 8 months for noncomplete responder group. In univariative analysis, statistically significant prognostic factors were tumor size, clinical stage, tumor response, and operation. In multivariative analysis, significantly better survival was associated with clinical stage, tumor response, radiation dose, and operation. Conclusion : Compared with radiotherapy alone, combined multimodality may improve the median survival in patients with localized carcinoma of the esophagus and toxicity is acceptable.

• 한국식품과학회지
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• 제30권4호
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• pp.775-780
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• 1998

우육의 위생화를 위한 방사선 조사기술의 이용 가능성을 검토할 목적으로 방사선 조사 쇠고기(5 kGy)를 대상으로 유전독성 및 급성독성 시험을 통한 안전성 평가를 실시하였다. 감마선 조사 및 비조사 쇠고기 현탁액의 S. typhimurium TA98, TA100, TA1535 및 TA1537에 대한 복귀변이 집락수를 조사한 결과, 대사활성계 도입 및 부재시 모두, 모든 시험균주에서 시험 적용 농도인 $0.1{\sim}8.3{\;}mg/plate$의 범위에서 복귀변이 집락수의 농도 의존적인 증가 혹은 감소를 보이지 않아 감마선 조사 쇠고기(5 kGy)는 돌연변이원성이 없는 것으로 판단되었다. 또한, 설치류 망상적혈구를 이용하여 감마선 조사된 쇠고기의 염색체 이상 시험을 수행한 결과, 감마선 조사 쇠고기는 시험적용 용량인 $1250{\sim}2500{\;}mg/plate$1의 범위에서 소핵을 가진 망상적혈구의 출현율이 음성대조군과 유의한 차이를 나타내지 않아 소핵을 유발하지 않음을 확인하였다. 조사 우육의 급성독성시험 시험결과, 전 기간을 통하여 마우스 암수 모두에서 조사우육(5 kGy)의 경구투여시 폐사동물은 관찰되지 않았으며, 체중변화도 대조군과 유의적인 차이를 보이지 않았다. 또한, 마우스와 랫드 암수 모두에서 본 시험물질에 의한다고 생각되는 어떠한 임상증상이나 유의할 만한 병변도 관찰되지 않았다.

• 방사선산업학회지
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• 제6권4호
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• pp.299-304
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• 2012

The quality properties of freeze-dried apples, pears, strawberries and pineapples gamma-irradiated at 0, 1, 2, 3, 4, and 5 kGy were evaluated to develop germ-free products for immuno-compromised patients. The initial count of total aerobic bacteria in non-irradiated apples, pears, strawberries and pineapple was 2.5, 3.1, 2.6, and $3.2{\log}\;CFU{\cdot}g^{-1}$, respectively. Microorganisms were not observed in apples after 1 kGy, in pears and strawberries after 4 kGy, and in pineapples at 5 kGy within a detection limit of $10{\log}\;CFU{\cdot}g^{-1}$. In addition, the sterilization of each sample was confirmed at the same dose. The score for the overall acceptance of freeze-dried fruit irradiated at a sterilization dose was 5.5 for apples, 4.1 for pineapples, and 4.0 for the other fruits, whereas that of non-irradiated control sample was 5.6 for apples, 5.2 for pears, and 5.8 for strawberries and pineapples with a 7-point scale. As a result, gamma irradiation of 1 kGy for apples, 4 kGy for strawberries and pears, and 5 kGy for pineapples is sufficient to sterilize each freeze-dried fruit with acceptable sensory properties.

• 방사선산업학회지
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• 제8권1호
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• pp.11-15
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• 2014

In this study, we investigated the applicability of the photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) methods for freeze dried fruits which are not allowed to be irradiated in Korea. Apples and persimmons samples that had been dried with a freeze drier were irradiated at a dose of 1, 3, 5, 7, and 10 kGy, using a gamma radiator with a cobalt-60 source. With the PSL method, the dried apples showed photon counts of less then 700 counts/60 s (negative) in all the samples, whereas the dried persimmons that were gamma-irradiated above 3 kGy yielded photon counts of between 700 and 5,000 counts/60 s (intermediate). The TL results showed that this technique is useful for detecting irradiated samples; the TL ratios ($TL_1/TL_2$) measured for the food samples at an irradiation dose of 1 kGy were 0.13 for dried apples and 0.79 for dried persimmons. With regard to the results of ESR spectroscopy, the strength of the ESR signals from the dried fruits increased linearly in a dosedependent manner. However, the characteristic signal was not found in all the samples. In conclusion, the TL methods only can be used for the detection of gamma-irradiated dried apples and persimmons.

• Nuclear Engineering and Technology
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• 제8권4호
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• pp.231-242
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• 1976

중 준위 방사성 폐액의 증발 농축물을 불용성 물질로 고형화하기 위해 blown asp-halt와 straight asphalt를 혼합사용하여 제조된 bitumen-waste 고화체로부터 방사성핵종의 용출에 대한 고화체의 호학적 특성 및 용출 조건의 영향에 대해서 조사하였다. 고압 및 저온하에서 120일동안 $^{90}$ Sr 및 $^{137}$Cs의 용출율은 상압 및 상온때 보다 낮은 용출율을 보였으며, 40wt%염을 함유한 고화체에 대한 인공 해수 및 증류수에 대한 용출율의 영향은 별로 차이점이 관찰되지 않았다. 순수 asphalt 및 고화체의 연화점은 $^{60}$Co 조사에 의해 총선량 증가와 함께 증가 됐으나, 5.8$\times$$10^{8}$ rad, 까지 조사된 asphalt는 부피 증가나 팽윤 현상이 나타나지 않았다. 또한 Infrared spectra에 의해 blown asphalt의 functional group을 확인하였고, 계속 방사선에 의한 영향등을 조사중이다.

• Radiation Oncology Journal
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• 제15권4호
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• pp.379-385
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• 1997

목적 : 난소 미분화배세포종은 젊은 가임기 여성에 발생하며 방사선에 대한 감수성이 높아 복식자궁전적출술 및 난관난소절제술 후 방사선치료를 시행하는 것이 통상적인 치료 방법이었다. 항암화학요법을 본격적으로 사용하기 이전에 서울내학교병원에서 방사선치료를 받은 환자를 대상으로 친료 성적을 분석하였다. 대상 및 방법 : 1980년 8월에서 1991년 5월까지 서울대학교병원 치료방사선과에서 방사선치료를 받은 18명을 대상으로 후향적 분석을 시행하였는데, 16명의 환자는 수술 후 방사선치료를 받았고, 나머지 2명은 근치적 목적으로 방사선치료를 받았다. 수술 후 방사선치료를 받은 환자들의 추적기간은 51개월에서 178개월로 중앙값은 99개월이었다. 연령분포는 11세부터 42세로 중앙값은 22세이었다. 병기별 분포는 IA기 3명, IC기 8명, 11기 2명, 111기 3명이었다. 1명의 환자에서 Turner's syndrome이 동반되어 있었다. 방사선치료는 6 MV와 10 MV 선형가속기나 Co-60 원 격치료장치를 이용하였으며, 전 복부에 1950-2100cGy(중앙값=2000cGy)후 골반부에 1050-2520cGy를 추가하여 골반부에 총 3000-4500cGy(중앙값=3500cGy)를 조사하였다. 5명의 환자에 서는 대동맥임파절 부위에 900-1500cGy를 조사하였고, 대동맥 임파절 전이가 있었던 1명에서는 1620cGy후 전이 부위에 900cGy를 추가하여 총 4470cGy를 조사하였다. 대동맥 임파절 전이가 있었던 1명을 포함한 5명의 환자에서는 종격동 및 쇄골 상부에 2520cGy를 조사하였다. 절제가 불가능하여 방사선치료만 받은 2명의 환자는 111기 1명과 좌측 쇄골상 임파절 전이가 동반된 IV기 1명이었다. III기 환자에서는 전 복부에 2000cGy후 골반부에 2070cGy, 대동맥 임파절에 2450cGy를, IV기 환자에서는 전 복부에 2000cGy후 골반부 및 대동맥 임파절에 2400cGy, 종격동에 2520cGy 그리고 좌측 쇄골 상부에 3550cGy를 조사하였다. 결과 : 난관난소절제술 후 방사선치료를 시행 받은 환자의 5년 국소 치유율은 $100\%$이었으며 종격동 조사를 시행하지 않은 131기 환자 1명에서 종격동 전이가 발생하였으나 항암화학요법으로 치유되어, 전체 환자에서의 5턴 생존율은 $100\%$를 보였다. 방사선치료만 받은 2명의 환자는 각각 112, 155개월간 무병 생존하고 있다. 결론 : 난소 미분화배세포종에 있어서 난관난소절제술 후 방사선치료는 물론 수술이 불가능한 경우의 방사선치료의 완치율은 매우 높았다. 그러나, 방사선만 아니라 항암화학요법에 대한 감수성이 높고 치유율이 높으므로 난소의 기능을 보존할 필요가 있는 경우에는 항암화학요법을 시행하고 항암화학요법에 저항성이 있거나 치료 후에 재발된 경우에 방사선치료를 적용하는 것이 타당할 것이다.