• 한국방사선학회논문지
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• 제7권2호
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• pp.113-120
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• 2013

현대시대는 환자에 대한 의료제도가 의료서비스 개념으로 변화되고 있다. 이렇게 인간의 권리가 높아지고 환자가 고객이 되는 시대로 변화됨으로써 환자의 권리나 요구도 날로 증가되고 있으며 이를 바탕으로 여러 가지 병원 시스템도 환자의 편의나 요구에 맞춰지고 있는 것이 현실이다. 이로 인해 일반촬영 검사 중 Portable 검사의 Case도 점차 증가하고 있는 추세이다. Portable 검사의 Case가 증가하면서 병실, 중환자실, 수술실, 회복실에서 Portable검사로 인하여 주변 환자들의 원하지 않는 의료 피폭이 발생하기 때문에 법적으로도 이를 규제하고 있다. 실제로 진단용 방사선 발생장치의 안전관리에 관한 규칙 중 방사선 방어시설의 검사기준에서 "수술실, 응급실 또는 중환자실 외의 장소에서 촬영할 경우 반드시 이동형 진료용엑스선 방어칸막이를 갖추어야 한다."고 명시되어 있지만 이는 거의 시행되어지지 않고 있다. 따라서 X-ray Potable 검사를 통해 주변 환자가 받는 피폭선량을 알아보고 피폭선량 감소 방안을 알아보고자 하였다. 본 연구는 Mobile Portable 장비에서 Collimator 주변을 차폐하여 차폐 전과 후의 선량 변화, Portable tube와 Collimator의 각도 변화에 따른 차폐 전과 후의 선량 변화, 환자 침대의 거리변화에 따른 차폐 전과 후의 선량 변화를 각각 측정한 뒤 차폐효과를 알아보았다. 연구 결과 Collimator 주변을 차폐한 후 선량 변화는 차폐하지 않았을 때보다 약 20%의 차폐효과를 보였다. Portable 검사 중 비 차폐 시 각도가 $0^{\circ}C$, $90^{\circ}C$, $45^{\circ}C$ 순서로 피폭선량이 증가하였으며, 각도를 주었을 때 Collimator 주변을 차폐하면 피폭 선량은 감소하였다. 또한 환자 침대 거리는 비 차폐 시 0.5m보다 1m에서 피폭선량이 현저히 감소하였고 침대 간 거리 변화 시 Collimator 주변 차폐 후 선량 변화는 감소하였다. 주변 환자 피폭선량 감소 측면에서 볼 때 침대거리를 가능한 멀리 떨어뜨리는 것이 가장 좋은 방법이며 차폐효과가 약 100% 내외로 상당한 효과를 볼 수 있다. 그 다음은 Collimator를 차폐하는 방법으로 차폐효과가 약 20% 정도를 나타내며, 각도를 제한하는 방법으로 약 10% 내외의 효과를 나타낸다. Portable 검사 시 환자 피폭선량을 감소하기 위해 가능한 환자 및 보호자를 적정거리 이상으로 이동시킨 후에 실시하는 것이 가장 좋겠지만 환자가 움직일 수 없고 침대가 고정되어 있는 상태에서는 Collimator 주변을 차폐하는 방안을 제안한다. 또한 검사를 시행할 때 tube와 Collimator의 각도를 가능한 90도로 시행하도록 하고 90도가 안될 경우는 0도로 시행하되 45도는 가능한 지양하도록 한다. 방사선관계종사자들은 Portable 검사에서 위와 같은 결과들을 인식하고 실제 본인에게 적용시켜야 하며 효율적인 방사선 방어와 피폭선량을 감소시킬 수 있는 방안에 대한 노력과 연구에 힘써야 할 것으로 사료된다.

• Toxicological Research
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• 제16권2호
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• pp.117-124
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• 2000

The objective of this experiment is to investigate neurobehavioral and developmental effects of fumonisin B1 (FB1) after prenatal FB1 administration in rats. FB1 (0.8 or 1.6 mg/kg) was orally exposed to pregnant rats during gestational days 13 to 20, whereas the vehicle alone was administered to control group. Maternal and offspring body weights, physical landmarks of incisor eruption, eye opening, testes descending and vaginal opening, open field activity, running wheel activity, and complex maze performance were included as endpoints for developmental and neurobehavioral measurement. Maternal body weights were not signfficantly altered after FB1 exposure. Percentage of maternal weight gain difference between control and 1.6 mg/kg FBI groups was about 4%. Pre- and post-weanling weight of offsprings after prenatal exposure to FB1 was not signfficantly changed, suggesting that FB1 at 0.8 or 1.6 kg/kg doses may not cross the placenta. Significant gender difference in running wheel activity on postnatal days 57 to 63 and complex maze performance on postnatal days 75 to 78 was observed.

• 제어로봇시스템학회논문지
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• 제9권4호
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• pp.296-303
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• 2003

A personal portable type electronic dosimeter using silicon PIN photodiode and small GM tube is recently attracting much attention due to its advantages such as an immediate indication function of dose and dose rate, alerting function, and efficient management of radiation exposure history and dose data. We designed and manufactured a semiconductor radiation detector aimed to directly measure X-ray and v-ray irradiated in silicon PIN photodiode, without using high-priced scintillation materials. Using this semiconductor radiation detector, we developed an active electronic dosimeter, which measures the exposure dose using pulse counting method. In this case, it has a shortcoming of over-evaluating the dose that shows the difference between the dose measured with electronic dosimeter and the dose exposed to the human body in a low energy area. We proposed an energy compensation filter and developed a dose conversion algorithm to make both doses indicated on the detector and exposed to the human body proportional to each other, thus enabling a high-precision dose measurement. In order to prove its reliability in conducting personal dose measurement, crucial for protecting against radiation, the implemented electronic dosimeter was evaluated to successfully meet the IEC's criteria, as the KAERI (Korea Atomic Energy Research Institute) conducted test on dose indication accuracy, and linearity, energy and angular dependences.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8171-8175
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• 2014

Background: To study the radioprotective effects of flavonoids from Rosa roxburghii Tratt (FRT). Materials and Methods: The radioprotective effects of FRT were investigated by examining cell viability, 30-day survival of mice and the number of colony-forming units in spleen (CFU-S) after total-body 60Co irradiation. Results: The survival rates of irradiated cells gradually increased with increasing concentrations of FRT. The survival rate was the highest at 87% with a concentration of $30{\mu}g/mL$. Pretreatment with FRT was needed to realize its radioprotective activity in mice at the dose of 60 mg/kg. With the increasing doses of 30 mg/kg, 60 mg/kg and 120 mg/kg, the numbers of CFU-S increased, and were significantly different compared with the control group. Conclusions: Pretreatment with FRT prior to irradiation resulted in significantly higher cell survival at 24 h after 5 Gy radiation, increased 30-day survival in mice after exposure to a potentially lethal dose of 8 Gy, and resulted in a higher number of CFU-S in mice after exposure to a dose of 6 Gy. These results collectively indicate that FRT is an effective radioprotective agent.

• Toxicological Research
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• 제16권1호
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• pp.89-94
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• 2000

Alpha-hydroxy acid(AHA) are used in cosmetic products as a pH adjuster, mild exfoliant and humectant-skin conditioner. Cosmetics containing higher concentration (30%) and lower pH (3.0) of AHA can cause side effects if it is applied without the prescription. For providing information on the safety of AHA and on human risk assessments we studied skin irritation effect of glycolic acid, one of the most commonly used AHA in guinea pigs. The skin irritation by glycolic acid was increased in a dose(10% to 70%), acidity (pH 2.5 to 5.5.) and length of exposure dependent manner (for up to 14 days), respectively. The combination treatment with UVB (0.4 or 3.0 J/$cm^2$) increased glycolic acid-induced skin irritation. Histological examination showed that hyperplasia of non-inflammatory cells in the epidermis of skin treated with high dose of glycolic acid (pH 3.0). There results show that glycolic acid increased skin irritation in a dose, length of exposure and pH dependent manner, respectively, in guinea pig, and the combination with UVB increased glycolic acid-induced skin irritation. The cell proliferation of non-inflammatory cell may be involved in high doses of glycolic acid-induced skin irritation. Long-term application of more than 30% of glycolic acid (pH 3.0) may cause skin irritation.

• Environmental Analysis Health and Toxicology
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• 제19권4호
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• pp.367-373
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• 2004

Mancozeb, a polymeric complex of zinc and manganese salts of ethylene bisthiocarbamate (EBDC), is used widely in agriculture as fungicides, insecticides, and herbicides. Mancozeb can be occupationally and environmentally exposed to human and has been reported to induce estrogenic activity, therein it is considered as an endocrine disrupter. After female ICR mice were treated Mancozeb orally at the doses of 250, 1,000 and 1,500 mg/kg/day for consecutive 30 day, we investigated the effects of Mancozeb on the immunopathological parameters (body-, thymus-, spleen-, liver- and kidny-weight, splenic cellularity, hematological parameters) and mitogen (Con A, LPS)-induced splenocyte proliferation (SP). Liver- and kidney- weight were increased, but body- and thymus-weight, number of splenocytes and WBC were decreased, when compared with control group. When splenocytes isolated from the mice exposed to Mancozeb for 30 days were cultured in presence of mitogens, the SP against Con A was significantly and dose-dependently decreased and the SP against LPS was also slightly decreased. Our present results indicate that subacute exposure of Mancozeb to mice might show immunotoxic effect.

• Archives of Pharmacal Research
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• 제14권2호
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• pp.188-192
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• 1991

Single non-lethal doses of chloroform $(CHCL_3)$ dichlorobromomethane $(CHCL_2Br)$, dibromochloromethane $(CHCIBr_2)$, or bromoform $(CHBr_3)$ were administered to male rats. Routes of exposure including single intraperitional (ip) and subcutaneous (sc) injection were used in order to permit comparison of severity of THM effects and renal toxicity was assessed at varied times following treatment. On an equimolar basis, sc administration of $CHBr_3$ (either 12 or 3 mmoles/kg) is more effective at increasing KW/BW than ip $CHCI_3$ treatment. Plasma urea nitrogen (BUN) following ip THM injections are markedly increased with all four THM at 24 hours post treatment. BUN response to $CHCL_2Br$ and $CHCIBr_3$-effected BUN levels have essentially returned to those of vehicle control. THM sc treatment results in a BUN response similar to that seen following ip treatment, with only the time course being different. With the exception of $CHCL_3$, sc and ip-treatments appear to be equally effective in evoking absolute BUN elevations. These results suggest that THM administration induce renal toxicity dependent upon the route or exposure.

• Imaging Science in Dentistry
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• 제35권4호
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• pp.203-205
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• 2005

Purpose: This study was aimed to compare skin entrance dose of digital radiography with that of film radiography and to show the dose reduction achievement with digital systems at 11 dental schools in Korea. Materials and Methods: Forty six intraoral radiographic systems in 11 dental schools were included in this study. Digital sensors were used in 33 systems and film was used in 13 systems. Researchers and the volunteer visited 11 dental schools in Korea. Researchers asked the radiologic technician (s) at each school to set the exposure parameters and aiming the x-ray tube for the periapical view of the mandibular molar of the volunteer. The skin entrance doses were measured at the same exposure parameters and distance by the technician for each system with a dosimeter (Multi-O-Meter : Unfors instruments, Billdal, Sweden). Results: The median dose was $491.2{\mu}Gy$ for digital radiography and $1,205.0{\mu}Gy$ for film radiography. The skin entrance dose in digital radiography was significantly lower than that of film radiography (p<0.05). Conclusion: Fifty-nine percent skin entrance dose reduction with digital periapical radiography was achieved over the film radiography in Korean dental schools.

• 대한방사선기술학회지:방사선기술과학
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• 제18권2호
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• pp.75-86
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• 1995

Embryos and fetuses are more sensitive to various environmental agents than adults of children biological effects following the exposure, such as intrauterin, malformation, have intimate conception with the prenatal exposure. There have been many studies on radiation and other agent. However, imformation about the ultrasound effects is limited. It is very important to study the effect of ultrasound with these kinds of fatera in consideration of ultrasound protection and safty. In this study, embryonic and fefal effects of ICR mouse embryos irradiated on 24, 48, 12 and 192 hpc of preimplantation and organogenesis period at the intensity of $0.5{\sim}3\;W/cm^2$ were investigated. Many type of external malformation observed in mouse irradiated on 72 hpc and 192 hpc. However, the embryos irradiated on 24 hpc and 48 hpc, at witch embryos had less then 6 cells and were pre-compaction stage, had no sensitivity for external malformation. The threshold doses of external malformation in mouse irradiated on 72 hpc and 192 hpc, at which embryos were consisted of $16{\sim}32$ cells and neural formation stage, were $1\;W/cm^2$ and $0.5\;W/cm^2$.

• 대한약침학회지
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• 제21권2호
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• pp.90-97
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• 2018

Silymarin is a flavonoid complex extracted from the Silybum marianum plant with a wide range of pharmacological and biochemical effects. In the present study, the immunomodulatory effects of silymarin were investigated in BALB/c mice. Silymarin was administered daily by intraperitoneal injection at doses of 50, 100 and 150 mg/kg for 14 consecutive days. Following the exposure, host hematological parameters, spleen cellularity and histopathological examination, as well as delayed-type hypersensitivity (DTH) responses, hemagglutination titers (HA), splenocyte cytokine production and lymphocyte proliferation assay were studied in all of the test groups of animals. The results showed that the low dose of silymarin (50 mg/kg) could stimulate both cellular and humoral immune functions in the treated hosts. In addition, silymarin at 100 mg/kg appeared to impact on DTH responses and lymphoproliferation. Based on the finding here, it would seem that silymarin has efficient immunostimulant properties. As a recommendation, the application of silymarin along with acupuncture technique (herbal acupuncture) can be thought as a good plan to modulate and enhance the immune system for the management of several immunodeficiency disorders. However, further studies are required to demonstrate this hypothesis.