• ETRI Journal
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• 제27권4호
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• pp.449-452
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• 2005

The electrical characteristics of solid state devices such as the bipolar junction transistor (BJT), metal-oxide semiconductor field-effect transistor (MOSFET), and other active devices are altered by impinging photon radiation and temperature in the space environment. In this paper, the threshold voltage, the breakdown voltage, and the on-resistance for two kinds of MOSFETs (200 V and 100 V of $V_{DSS}$) are tested for ${\gamma}-irradiation$ and compared with the electrical specifications under the pre- and post-irradiation low dose rates of 4.97 and 9.55 rad/s as well as at a maximum total dose of 30 krad. In our experiment, the ${\gamma}-radiation$ facility using a low dose, available at Korea Atomic Energy Research Institute (KAERI), has been applied on two commercially available International Rectifier (IR) products, IRFP250 and IRF540.

• 대한두경부종양학회지
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• 제14권1호
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• pp.61-69
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• 1998

Objectives: The response rate of the radioactive iodine(RI) therapy with low dose was variable. Only a few studies reported the response and complication rate with high dose. The goal of this study was to access the ablation and complication rate after high dose of RI therapy (more than 100mCi) and to evaluate the factors affect the results. Material and Methods: During a period of 12 years, 225 patients received high dose of RI from 100 to 200mCi depending on the RI uptake in the whole body after total thyroidectomy. 100mCi of RI was given to 123 patients for ablation who showed the uptake only in the thyroid bed. 150mCi was given to another 84 patients for ablation who had uptake confined to the neck. The other 21 patients took more than 200mCi of RI because the whole body scan showed distant metastasis. Among these patients, the ablation and the complication rate was investigated. Results: Elevated level of the serum thyroglobulin(Tg) decreased less than 5ng/ml after RI therapy in all patients except two in the first group. The second group showed reduction of the serum Tg in 93%. Eighteen of the 21 patients in the third group are still alive after RI therapy. There were no fatal complications after high dose RI therapy and most of the complications were minimal and transient. The complication rate was not related with the dose of RI, age, sex, DNA flowcytometry, serum thyroglobulin level and the extent of node dissection. Conclusion: We concluded that RI therapy with high dose was very effective for thyroid ablation after operation and it also showed excellent results with minimal complications for treatment of metastatic lesions.

• Asian Pacific Journal of Cancer Prevention
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• 제16권10호
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• pp.4369-4376
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• 2015

Background: To investigate in-vitro antagonistic effect of low-dose liquiritigenin on gemcitabine-induced capillary leak syndrome (CLS) in pancreatic adenocarcinoma via inhibiting reactive oxygen species (ROS)-mediated signalling pathways. Materials and Methods: Human pancreatic adenocarcinoma Panc-1 cells and human umbilical vein endothelial cells (HUVECs) were pre-treated using low-dose liquiritigenin for 24 h, then added into gemcitabine and incubated for 48 h. Cell viability, apoptosis rate and ROS levels of Panc-1 cells and HUVECs were respectively detected through methylthiazolyldiphenyl-tetrazoliumbromide (MTT) and flow cytometry. For HUVECs, transendothelial electrical resistance (TEER) and transcellular and paracellular leak were measured using transwell assays, then poly (ADP-ribose) polymerase 1 (PARP-1) and metal matrix proteinase-9 (MMP9) activity were assayed via kits, mRNA expressions of p53 and Rac-1 were determined through quantitative polymerase chain reaction (qPCR); The expressions of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and PARP-1 were measured via western blotting. Results: Low-dose liquiritigenin exerted no effect on gemcitabine-induced changes of cell viability, apoptosis rate and ROS levels in Panc-1 cells, but for HUVECs, liquiritigenin ($3{\mu}M$) could remarkably elevate gemcitabine-induced decrease of cell viability, transepithelial electrical resistance (TEER), pro-MMP9 level and expression of ICAM-1 and VCAM-1 (p<0.01). Meanwhile, it could also significantly decrease gemcitabine-induced increase of transcellular and paracellular leak, ROS level, PARP-1 activity, Act-MMP9 level, mRNA expressions of p53 and Rac-1, expression of PARP-1 and apoptosis rate (p<0.01). Conclusions: Low-dose liquiritigenin exerts an antagonistic effect on gemcitabine-induced leak across HUVECs via inhibiting ROS-mediated signalling pathways, but without affecting gemcitabine-induced Panc-1 cell apoptosis. Therefore, low-dose liquiritigenin might be beneficial to prevent the occurrence of gemcitabine-induced CLS in pancreatic adenocarcinoma.

• 한국환경농학회지
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• 제18권4호
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• pp.344-348
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• 1999

배추와 무의 영양생리에 대한 저선량${\gamma}$선에 의한 자극작용의 영향을 파악하고자 1998년산 흑진주배추, 1995년산 서림엇갈이배추, 1998년산 청운무 종자에 1에서 10Gy의 저선량 ${\gamma}$선을 조사하고 생육시기에 따른 생장량과 무기양분의 변화를 분석하였다. 공시된 배추품종들은 조사선량의 증가에 따라서 발아율과 건물생산량이 증가하는 경향을 보였다. 건물생산의 증가는 흑진주배추에서 가장 현저하여 10Gy 처리구에서 143%로 증가되었고, 서림엇갈이배추는 10Gy에서 138%로 증가하였다. 청운무는 ${\gamma}$선 조사에 따른 발아율과 건물생산량의 일관된 경향성을 보이지 않았다. 무기영양소들의 함량변화는 선량-반응 곡선의 ${\gamma}$ 또는 ${\delta}$형을 나타내 ${\gamma}$선에 의한 자극효과가 일부처리구에서 나타나기는 하였지만 일반적 현상이라고 인정하기 어려웠다. 따라서 저선량 ${\gamma}$조사가 배추와 무의 영양생리에 미치는 영향을 정확하게 파악하기 위한 연구결과의 집적이 필요할 것으로 판단된다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3589-3593
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• 2012

Objective: Evaluation and assessment of response rate, duration and toxicity in patients subjected to 5-FU based chemotherapy. Background: The therapeutic ratio shifts with different 5FU/LV regimens and none yet serve as the internationally accepted Gold Standard. A bimonthly regimen of high dose leucovorin is reported to be less toxic and more effective than monthly low dose regimens. We here compare therapeutic responses and survival benefit of the two regimens in poor prognosis patients with advanced colorectal carcinoma. Patients and Methods: A total of 35 patients with histologically confirmed colorectal carcinoma were subjected to de Gramont and Mayo Clinic regimen. Nineteen patients were treated with high dose folinic acid ($200mg/m^2$), glucose 5%, 5-FU ($400mg/m^2$) and 22 hr. CIV ($600mg/m^2$) for two consecutive days every two weeks. These patients had failed responses to previous chemotherapy and were above sixty years of age with poor general status. Sixteen patients (six below 60 years) with progressive disease were subjected to low dose folinic acid ($20mg/m^2$)for five days, 5FU($425mg/m^2$) injection bolus for 5 days, every five weeks. An initial evaluation was made in sixty days and responders were reevaluated at sixty days interval or earlier in case of clinical impairment. Based on positive prognosis, the therapy was continued. Evaluation of treatment response was made on the basis of WHO criteria. Results: The response rate was 44% in thirty four evaluable patients, with 4 complete responses (11.8%) and 11 (32.4%) partial responses. The two schedules were well tolerated, whereas, mild toxicity without WHO Grade ${\geq}2$ events was assessed. The response duration was extended (12 months) in a few patients with age above sixty years treated by high dose bimonthly regimen of 5FU/LV. Conclusion: The regimens are safe and effective in advanced colorectal carcinoma patients with poor general status.

• Journal of Dental Anesthesia and Pain Medicine
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• 제23권4호
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• pp.221-228
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• 2023

Background: We assessed the relationship between patient age and remifentanil dosing rate in patients managed under general anesthesia with spontaneous breathing using low-dose remifentanil in sevoflurane. Methods: The participants were patients with an American Society of Anesthesiologists Physical Status of 1 or 2 maintained under general anesthesia with low-dose remifentanil in 1.5-2.0% sevoflurane. The infusion rate of remifentanil was adjusted so that the spontaneous respiratory rate was half the rate prior to the induction of anesthesia, and γ^H (㎍/kg/min) was defined as the infusion rate of remifentanil under stable conditions where the respiratory rate was half the rate prior to the induction of anesthesia for ≥ 15 minutes. The relationship between γ^H and patient age was analyzed statistically by Spearman's correlation analysis. Results: During dental treatment under general anesthesia using low-dose remifentanil in sevoflurane, a significant correlation was detected between γ^H and patient age. The regression line of y = - 0.00079 x + 0.066 (y-axis; γ^H, x-axis; patient's age) was provided. The values of γ^H provide 0.064 ㎍/kg/min at 2 years and 0.0186 ㎍/kg/min at 60 years. Therefore, as age increases, the dosing rate exhibits a declining trend. Furthermore, in the dosing rate of remifentanil when the patient's respiratory rate was reduced by half from the preanesthetic respiratory rate, the dosing rate provided was around 0.88 mL/h in all ages if the remifentanil was diluted as 0.1 mg/mL. EtCO₂ showed 51.0 ± 5.7 mmHg, and SpO₂ was controlled within the normal range by this method. In addition, all dental treatments were performed without major problems, such as awakening and body movement during general anesthesia, and the post-anesthetic recovery process was stable. Conclusion: General anesthesia with spontaneous breathing provides various advantages, and the present method is appropriate for minimally invasive procedures.

• 환경생물
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• 제18권2호
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• pp.247-253
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• 2000

저선량 ${\gamma}$선이 시판중인 배추 신규종자인 "만점" 배추와 묵은 종자인 "서림엇갈이" 배추의 발아와 초기생육 및 생리활성에 미치는 영향을 조사하였다. 배추종자의 발아와 초기생육에 있어 신규종자에서는 별효과가 없었으나 묵은 종자에서는 촉진효과가 있었고 그 적정 선량은 1.0Gy와 2.0Gy였다. 배추유식물체의 엽록소 함량은 저선량 조사구가 대조구보다 높았으며 조사선량의 증가에 따라 대체로 증가하였고, 저선량 조사에 의한 배추유식물체의 항산화효소 활성은 증가하였으나 낮은 선량에서 증가하였고 높은 선량에서는 감소하였다.가하였고 높은 선량에서는 감소하였다.

• 한국발생생물학회지:발생과생식
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• 제22권1호
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• pp.85-94
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• 2018

Endocrine disruptors have been concerned in toxicology but now challenged as physiological point especially concerned with exposing dose and period. In this study the low-dose chronic administration of di(2-ethylhexyl) phthaltae (DEHP) during reproductive period was examined to evaluate the possible roles. Adult male and female CD-1 mice were exposed to DEHP with drinking water containing $133{\mu}g/L$ and $1,330{\mu}g/L$ DEHP in water according to OECD 433 guide line and sacrificed just after weaning. The weights of uterus and ovary were decreased by drinking of $1,330{\mu}g/L$ DEHP water. There was not adverse effects on either accumulated mating rate and mating rate depend on estrus stage, pregnancy duration, and sex ration at birth. However, the accumulated rate of successful delivery and litter size were significantly high at $1,330{\mu}g/L$ DEHP water. The number of epididymal sperm was significantly increased by drinking of $1,330{\mu}g/L$ DEHP water. In addition, the number of follicles (primary, secondary, tertiary) were more many than control at $1,330{\mu}g/L$ DEHP water drunk mother. Though further studies are needed to identify what are the mechanism of DEHP in folliculogenesis and spermatogenesis. From this study we firstly report the effect of low-dose chronic administration of DEHP with drinking could change the ovarian follicle population size and spermatogenesis rate. Put together, those finding is different from previous high-dose effects and suggest the physiological role of DEHP in gonads and uterus.

• 환경생물
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• 제19권1호
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• pp.71-77
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• 2001

저선량 방사선 조사한 고추 2품종, 조광고추와 조흥고추의 종자 발아율과 초기생육 및 고추 유식물체의 후속 고선량에 대한 내성 변화를 알아보고자 저선량 0, 4, 8, 20, 50 Gy를 조사하여 재배한 고추 유식물체에 ${\gamma}$선 50 Gy와 100 Gy를 조사한 후 생육상황을 관찰하였다. 저선량 조사한 고추 유식물체의 초기생육 촉진과 후속고선량 내성은 품종에 따라 달랐는데, 조광고추보다 조홍고추 품종에서 뚜렷한 증가효과를 나타냈고 발아율과 초기생육촉진은 4, 8, 20 Gy 조사구에서 효과적이었다. 조홍고추 유식물체의 후속고선량에 대한 내성은 사전 저선량 조사에 의해 크게 증가되었는데 특히 4Gy조사구에서 효과가 가장 뚜렷하였으며 후속고선량에 대해 내성이 증진된 고추 유식물체중의 carotenoid와 단백질 함량 및 CAT활성은 4 Gy와 8 Gy 조사구에서 높았다.

• Clinical and Experimental Pediatrics
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• 제52권4호
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• pp.441-445
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• 2009

목 적 : 아미노필린을 낮은 농도(5 mg/kg/day)에서부터 점진적으로 증량할 때와 일상 용량(10 mg/kg/day)으로 시작할 때 나타나는 부작용을 비교하고자 하였다. 방 법 : 2007년 3월부터 2008년 1월까지 인하대병원 소아과에 호흡기질환으로 입원한 환아들을 대상으로 정주 아미노필린의 투여 용량을 달리하여, 투여 후 3일간의 활력 징후, 부작용 및 혈중 농도를 조사하였다. 결 과 : 저용량군 37명, 일반용량군 21명, 대조군 9명이었다. 저용량군과 보통용량군 간의 입원 시 연령, 신체활력징후, 혈액검사의 차이는 없었다. 경련과 같은 심각한 부작용은 없었다. 저용량군에서는 9명(24.3%)이 보챔, 수면장애로 아미노필린 사용을 중단하였으며, 일반용량군에서는 6명(28.6%)이 아미노필린 투여를 중단하였고, 투여를 중단한 경우의 혈중 농도($(3.68{\pm}1.93{\mu}g$/mL)와 중단 없이 사용한 군의 혈중농도($(4.47{\pm}2.45{\mu}g$/mL)의 차이는 없었다. 투여를 중단하게 된 경우는 대부분 2세 미만의 환자에서 발생하였다. 결 론 : 저자들은 급성 천식환자에서 정주 아미노필린의 부작용은 초기 투여용량과는 관계가 없다고 생각하며, 본 연구에서 사용한 용량보다 고용량 투약에 따른 연구 및 연령에 따른 연구가 필요할 것으로 생각한다.