• 치과방사선
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• 제9권1호
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• pp.25-31
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• 1979

The utilization of x-ray for diagnosis and examination is increasing by about 5-15% every year, therefore, it would be mandatory to protect the patients from exposures and so, studies in this field are performed even now. In dental field, the area of irradiation is limited any to the head and neck area, but the irradiated angle is varied following the objected tooth, so the adjacent structures lens and thyroid gland would be fragile to radiation. And the scattered radiation is one of the complicated problems in the protection because of specificity of dental x-ray and its object structures. The author, by using TLD (Thermo luminescent Dosimeter; Teledyne Isotopes-Model 7300, Element; TLD 200(CaF₂:Dy) and Capintec(Capintec Model 192, PM-30 Diagnostic chamber 28㎖ active volume), tried a measurement of air dose distribution of the scattered radiation and the irradiated dose of lens and thyroid gland under the condition of taking the film on the left maxillary molar. The results were as follows: 1. The half value layer of adapted dental x-ray machine was measured, and is 1.44㎜ Al. 2. The time of irradiation on the left maxillary molar in the Alderson Rando Phantom, the measured doses of left and right lens, and thyroid gland were 8,9mR, 1,2mR and 2,8mR. Under the same conditions, the scattered radiation at the distance of 1 meter from the phantom were 84 μR at the front side, 11μR at the back side, 18μR at the right side and 72μR at the left side. 3. Under the same conditions, the dose showed higher value by about 5% in the presence of object(phantom) than in the case of absence.

• 대한방사선기술학회지:방사선기술과학
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• 제44권5호
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• pp.435-441
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• 2021

The purpose of this study was to evaluate the quality of images and to quantitatively measure and analyze the dose of scattered ray to the organs, which were highly sensitive to radiation according to the use of cylinder cone in mastoid process radiography. When the cylinder cone was not used, the SID was 100cm and the field size was 24 × 36 cm(864 cm²). When using the cylinder cone which was a circle, the SID was 70 cm, the radius was 10.5 cm and field size was 86.59 cm². As a result of the study, SNR of the image quality evaluation was measured to be 2.58 for Law method and 3.90 for Stenver's method when not using cylinder cone, and 2.87 for Law method and 14.67 for Stenver's method when using cylinder cone. CNR was measured to be 0.03 for Law method and 0.04 for Stenver's method when cylinder cone was not used, and 0.04 for Law method and 0.05 for Stenver's method when using cylinder cone. When the cylinder cone was not used, the scattered ray dose was measured to be 0.10 mGy in the right eyeball, 0.30 mGy in the left eyeball, 2.02 mGy in the parotid gland, and 0.29 mGy in the thyroid gland for Law method and to be 0.03 mGy in the right eyeball, 0.12 mGy in the left eyeball, 1.43 mGy in the parotid gland, and 0.09 mGy in the thyroid gland for Stenver's method. When the cylinder cone was used, the scattered ray dose was measured to be 0.05 mGy in the right eyeball, 0.03 mGy in the left eyeball and the parotid and thyroid gland were below the measurable values for Law method and all areas were below the measurable values for Stenver's method. This was found to be statistically significant(p<0.000).

• BMB Reports
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• 제28권6호
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• pp.515-522
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• 1995

The effects of the thyroid hormone ($T_3$) on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity were evaluated in a baby hamster kidney cell line, C100. The cells cultured in MEM were supplemented with 10% thyroid hormone-depleted fetal bovine serum (THDS-MEM) and had a 82.5% lower level of HMG-CoA reductase activity than the cells grown in a medium supplemented with fetal bovine serum (FBS-MEM). When $T_3$ was supplemented to THDS-MEM, the reduction of the reductase activity was blocked in a dose-dependent manner. In the cells grown in THDS-MEM containing $T_3$ at a concentration of $10^{-6}$ M, the level of HMG-CoA reductase activity was 91.8% relative to the cells grown in FBS-MEM. These changes in HMG-CoA reductase activity seemed to be at least partly due to the changes of HMG-CoA reductase mRNA levels. The level of HMG-CoA reductase mRNA in cells incubated in THDS-MEM decreased to 76.2% relative to the cells grown in FBS-MEM, while the level of reductase mRNA in cells incubated in THDS-MEM containing $T_3$ at a concentration of $10^{-6}$ M increased to 243.4% relative to the cells grown in FBS-MEM. The increase of HMG-CoA reductase mRNA level after $T_3$ treatment may have been due to the increased stability of reductase mRNA, because the transcriptional rate of the reductase gene did not change significantly in the presence or absence of $T_3$. These results indicate that $T_3$ stabilizes HMG-CoA reductase mRNA at the posttranscriptional level and regulates HMG-CoA reductase activity in a dose-dependent manner.

• 대한두경부종양학회지
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• 제18권2호
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• pp.142-149
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• 2002

본 연구에서는 FRTL-5 갑상선세포에서 Protein phosphatase type 1(PP-1)과 type 2A(PP-2A) 효소의 억제제인 okadaic acid에 의한 apoptosis 유도 기전에 대하여 이해하고자 하였다. FRTL-5 갑상선세포에 다양한 농도($10{\sim}80nmol$)의 okadaic acid를 처리 한 후 caspase 3와 $PLC-{\gamma}1$ 분절을 확인 한 결과 40nmol 농도에서부터 caspase 3활성과 $PLC-{\gamma}1$ 분절이 나타남을 확인하였다. Okadaic acid에 의한 apoptosis 유도 기전을 조사한 결과 anti-apoptotic 기능이 있는 Bcl-2 단백질 발현은 미약하게 감소하였으나 Bcl-xL은 농도 의존적으로 급격한 감소를 보였다. Caspase 3 효소활성을 저해하는 IAP 단백질 중 cIAP2는 okadaic acid에 영향을 받지 않았으나 cIAP1과 XIAP 단백질 발현은 농도 의존적으로 감소하였다. Okadaic acid에 의한 apoptosis 유도는 caspase 3 의존적인 기전을 보였다. Caspase 3 특이억제제를 okadaic acid와 동시에 처리 시 apoptosis가 억제되었으며 $PLC-{\gamma}1$ 단백질의 절단 현상도 방지되었다. Caspase 3의 활성을 유도하는 cytochrome c의 유리는 okadaic acid처리 농도에 의존적으로 유리하였다. 결론적으로, okadaic acid에 의한 apoptosis 유도는 caspase 3 의존적이며, Bcl-2와 IAP family 단백질 감소현상에 의하여 야기되는 것으로 생각된다.

• Radiation Oncology Journal
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• 제12권1호
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• pp.59-66
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• 1994

1986년 9월부터 1992년 10월까지 경북대학교병원 치료방사선과에서 방사선치료 단독요법이나 수술 흑은 화학요법과의 병합요법으로 치료받은 두경부종양 환자 75명을 대상으로 경부 방사선조사가 갑상선기능에 미치는 영향을 평가하기 위하여 전향적 조사를 실시하였다. 모든 환자는 방사선치료전 및 방사선치료후에 정기적으로 임상검사 및 갑상선 기능검사를 시행하였다. 갑상선조사선량은 35Gy에서 60Gy였고 그 중앙값은 50Gy였으며 추적관찰기간은 11개월에서 85개월로 중앙추적기간은 30개월 이었다. 결과를 보면 갑상선 기능이상의 빈도는 40$ \% $(30명)이었다. 45명(60$ \% $)은 갑상선 기능이 정상이었으며 2명(3$ \% $)은 임상적 갑상선 기능저하증 이었고 27명(36$ \% $)은 준임상적 갑상선 기능저하증 이었다. 갑상선 기능항진증이 1명(1$ \% $)에서 발견되었으며 갑상선 결절이나 악성종양은 발견되지 알았다. 수술 및 방사선치료군에서 갑상선 기능이상이 다른 치료군에서보다 일찍 발생하였다(p=0.0013). 다변량분석에 따르면 방사선치료후 갑상선 기능이상의 발생빈도에 영향을 주는 위험인자는 여성(p=0.0293) 및 전후두절제술과 방사선치료의 병합요법(p=0.0045)였다. 결론적으로 방사선치료후 정확한 시기에 갑상선 기능이상을 발견하기 위하여 방사선 치료전 및 방사선 치료후에 정기적인 갑상선 기능검사가 필요하며 갑상선 기능이상이 발견되면 즉시 갑상선 호르몬제재 치료를 하여야 하겠다.

• 한국방사선학회논문지
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• 제6권4호
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• pp.281-290
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• 2012

경상북도에 소재한 3개 종합병원 영상의학과의 MDCT 검사 중 두부, 복부, 흉부 각 10건씩 30건을 대상으로 CTDIl, DLP, Slice 수, DLP/Slice 수를 조사하여 병원 간 프로토콜의 차이로 인한 MDCT의 피폭선량의 차이를 분석하였고, CT검사의 가장 많은 검사건수를 차지하고 프로토콜이 비교적 단순한 두부 CT를 Helical Scan과 Normal Scan으로 2회 실시하여 영상의 화질, CTDI, DLP, 안구의 피폭선량, 갑상선의 피폭선량의 차이를 분석하였다. 두부CT에서 조사대상 병원의 3분의 2에서 CTDI 참조준위(IAEA 50mGy, 우리나라 60mGy)를 초과하지 않은 A병원에 비하여 유의하게 높았다(p<0.001). DLP에서 조사병원의 3분의 1은 참조준위 IAEA 1,050mGy.cm, 우리나라 1,000mGy.cm의 권고량 보다 높았고, 3분의 2가 우리나라의 권고량을 초과하고 있었다. 참조준위를 초과하지 않은 A병원에 비하여 유의하게 높았다(p<0.001). Abdomen CT에서도 3분의 1은 CTDI 참조준위 IAEA 25mGy, 우리나라 20mGy보다 높은 119mGy를 보였고, DLP에서는 모든 조사대상 병원이 우리나라 권고량 700mGy.cm보다 높았다. 조사대상 병원 중 모든 검사에서 높은 선량을 보인 C병원은 MPR, 3D 검사의 비중이 높아 낮은 pitch, 높은 관전류 검사로 인한 피폭선량이 높았다. Scan 방법에 따른 피폭선량의 차이를 분석하고자 동일환자의 두부CT를 Normal scan과 Helical scan으로 각각 실시하여 분석한 결과 CTDI 및 DLP에서 Helical CT가 Normal scan에 비해 63.4%, 93.7% 높은 선량을 보였다(p<0.05, p<0.01). 그러나 갑상선의 피폭선량은 Normal scan이 87.26% 높았다(p<0.01). Helical CT의 선속은 종심부와 변연부의 모양이 종의 형태를 취하고 있어 두부CT에서 갑상선은 중심선속에서 벗어난 적은 선량으로 피폭된다. 또한 Helical scan시 Gantry 각을 수직으로 사용하였고, Normal scan시에는 Orbitomeatal line에 평행으로 정렬된 Gantry 각을 사용하여 Helical scan에서 갑상선은 피폭선량이 감소하였다. 그러나 본 연구에서 사용된 프로토콜은 식약청의 표준준위에 비해 높은 피폭선량을 보여 식약청의 권고량을 지키기 위해서는 낮은 관전류 높은 Pitch의 사용이 요구되었다. 이번 연구에서 Normal scan과 Helical scan에 따른 화질의 차이는 없는 것으로 분석되어 특별한 경우가 아니면 Normal scan의 표준화된 프로토콜을 사용하고 갑상선의 보호장구를 사용하는 것이 필요하였다. 이번 연구는 일지역의 CT검사 중 일부를 조사하여 분석하였으므로 CT검사의 전체를 평가하는데 무리가 있었다. 그러나 경우에 따라 환자피폭선량의 가이드 권고량을 초과하고 있음을 알 수 있었고, 병원 간의 피폭선량 편차도 있음을 확인 할 수 있었다. 이것을 개선하기 위하여 영상의학과 의사 및 방사선사는 CT 방사선량을 줄이는 최적화된 프로토콜로 CT검사를 시행해야 하고, 환자의 알권리를 위하여 피폭선량은 공개되어야 한다. 그러나 아직 많은 의사들과 방사선사는 이에 대한 인식이 부족하므로 개선을 위하여 CT선량 저감화의 교육프로그램, CT검사에 따른 피폭선량의 공개, 병원의 서비스평가 및 병원인증제 평가항목에 CT검사 피폭선량관리 및 공개항목을 추가 등의 관련기관의 노력과 의료종사자가 CT검사에서 행위의 최적화를 실현하는 최선의 프로토콜을 사용하는 노력이 필요하였다.

• 대한의생명과학회지
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• 제14권1호
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• pp.59-62
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• 2008

This experiment was performed to study the effect of TSH (thyroid-stimulating hormone) on the expression of endoplasmic reticulum (ER) chaperones in the rat thyrocytes FRTL-5 cells. Although the expressions of ER membrane kinases (ATF6, IRE1 and PERK) were specially enhanced under absence of TSH, no remarkable up- or down regulations of ER chaperones (BiP, CHOP and Calnexin) were detected by TSH. We firstly report here that TSH by dose up-regulated expression of ER membrane kinases in FRTL-5 culture thyrocytes.

• Journal of Nutrition and Health
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• 제44권1호
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• pp.82-91
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• 2011

The present study reviewed the effects of excess iodine intake on thyroid function and the incidence of thyroid disease and discussed the scientific basis for establishing a tolerable upper intake level (UL) of iodine for Koreans. ULs are defined as "the highest level of daily nutrient intake that is likely to pose no risk of adverse effects to almost all individuals in the general population." Koreans consume excess iodine from seaweed, and iodine intake is strongly influenced by seaweed consumption. However, no dose-response data derived from subjects consuming excess iodine frequently but not continuously during a lifetime are available. Therefore, the Korean DRI committee set the iodine UL to reduce the risk of adverse health effects by excess iodine intake for Koreans with distinctive seaweed-eating habits.

• 대한본초학회지
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• 제25권3호
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• pp.11-18
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• 2010

Object : This study was to evaluate the effect of Ginseng Radix, aqueous extracts of the root part of Panax ginseng on the 6-n-propyl-2-thiouracil(PTU)-induced rat hypothyroidism. Methods : Aqueous extracts of Ginseng Radix(GR; yield = 11.70%) were administered, once day for 42 days from 2 weeks before start of PTU treatment as an oral dose of 300 and 150 mg/kg(body weight), and hypothyroidism was induced by daily subcutaneous treatment of PTU 10mg/kg for 28 days. The changes in the body weight, thyroid gland weights, serum levels of thyroid hormone-thyroid stimulating hormone(TSH), tri-iodothyronine(T3) and thyroxine(T4), total cholesterol, low density lipoprotein(LDL), high density lipoprotein(HDL) and triglyceride, liver antioxidant defense system-lipid peroxidation, $H_2O_2$, superoxide dismutase(SOD) and catalase(CAT) were observed with histopathology of thyroid glands. Results : Results were compared with LevoT4 0.5mg/kg treated rats. GR extracts suppressed the decreases in the body weight, thyroid gland weights, T3 and T4, TG, liver $H_2O_2$ and SOD activities as results of PTU treatment. And GR extracts suppressed the increases of HDL contents, liver CAT activities, thyroid gland weight as results of PTU treatment. In addition, marked hyperplasia of follicular cells with decreases of follicular colloid contentsand sizes were demonstrated at histopathological inspections. However, these PTU-induced histopathological changes related to hypothyroidism were dramatically decreased by treatment of both different dosages of GR extract, respectively Conclusions : This study suggest that GR extracts have favorable effects on the thyroid hormone productions with beneficial effects on the hypothyroidism mediated by the modulatory effects on the antioxidant defense system.

• 대한한의학방제학회지
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• 제24권3호
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• pp.131-152
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• 2016

Objectives ： This study was to evaluate Sibjeondaebo-tang’s(Shiquan dabutang) effect to rat hypothyroidism which induced by 6-n-propyl-2-thiouracil(PTU)Methods ： Aqueous extracts of Sibjeondaebo-tang(Shiquan dabutang)(21.29%) were administered by oral dose of 300 and 150 mg/kg(rat’s body weight) for 42 days from 2 weeks before start of PTU treatment. During this moment the body weight, thyroid gland weights, liver weight, serum thyroid hormone, lipid content and liver antioxidant defense system were measured with histopathological changes of thyroid glands, Liver and these result were compared with LevoT₄ 0.5mg/kg treated ratsResults ： As a result of PTU treatment, marked decreases of body weight, liver weight, serum thyroid hormone levels of T₃, T₄, triglyceride content and liver CAT activation were observed with marked increases of thyroid gland weight, thyroid gland hormone TSH, activate liver H₂O₂ and SOD, serum Total cholesterol, HDL and AST amount were admitted. In addition, marked hyperplasia of follicular cells with reduce of follicular colloid contents and sizes were showed at histopathological inspections. These PTU-induces histopathological changes related to hypothyroidism were significantly reduced by treatment of both different dosages of Sibjeondaebo-tang(Shiquan dabutang).Conclusions： This study suggest that Sibjeondaebo-tang(Shiquan dabutang) extracts have favorable effect on the thyroid hormone productions with beneficial effect on hypothyroidism medicated by modulatory effects on antioxidant defense system.