• Toxicological Research
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• 제17권3호
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• pp.203-213
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• 2001

We investigated the toxic effects of propylthiouracil (PTU) In Sprague-Dawley (SD) rats to develop and validate an enhanced Protocol for Test Guideline 407 as OECD Project. Twenty male and female SD rats,7 weeks old, were treated with PTU in corn oil at levels of 0, 0.1, 1 and 10 mg/kg/day for 4 weeks orally. Clinical observation, body weight changes, food uptake, water consumption, urinalysis, estrus cycle and sperm analysis, serum chemist교, autopsy findings and histopathological findings were evaluated in this study. No clinical signs and mortality were observed in the study. The body weights and food uptakes in the group treated with 10 mg/kg/day were reduced from 3 weeks after the initiation of the treatment. The levels of 3,5,3'-triiodothyronine (T3) and thyroxine (T4, 3,5,3',5'-tetraiodothyrosine) were also significantly decreased in the group treated with 10 mg/kg/day. Also, the relative and absolute organ weights of thymuses were decreased. Thyroid glands of rats in the group treated with PTU 10 mg/kg/day were bigger than those of rats in the control group. In the histopathological examination, diffuse hyperplasia and hypertrophy of thyroid follicular cells were observed in all treatment groups, leading to the reduction of lumen size and papillary enfolding of lining epithelium. The degree of lesion was increased in a dose-dependent manner. The results suggested that PTU would cause toxicity in thyroid gland and decrease the levels of T3 and T4 in SD rats. However there were no effects on the other organ including testis and uterus especially in spermatogenesis and estrus cycle. On the basis of the results, enhanced protocol for Test Guideline (TG) 407 may be sensitive and reliable to detect endocrine-active substances like PTU.

• Restorative Dentistry and Endodontics
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• 제41권1호
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• pp.1-5
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• 2016

Objectives: The purpose of this study was to assess the ability of ProTaper Gold (PTG, Dentsply Maillefer) in maintaining the original profile of root canal anatomy. For that, ProTaper Universal (PTU, Dentsply Maillefer) was used as reference techniques for comparison. Materials and Methods: Twenty simulated curved canals manufactured in clear resin blocks were randomly assigned to 2 groups (n = 10) according to the system used for canal instrumentation: PTU and PTG groups, upto F2 files (25/0.08). Color stereomicroscopic images from each block were taken exactly at the same position before and after instrumentation. All image processing and data analysis were performed with an open source program (FIJI). Evaluation of canal transportation was obtained for two independent canal regions: straight and curved levels. Student's t test was used with a cut-off for significance set at ${\alpha}=5%$. Results: Instrumentation systems significantly influenced canal transportation (p < 0.0001). A significant interaction between instrumentation system and root canal level (p < 0.0001) was found. PTU and PTG systems produced similar canal transportation at the straight part, while PTG system resulted in lower canal transportation than PTU system at the curved part. Canal transportation was higher at the curved canal portion (p < 0.0001). Conclusions: PTG system produced overall less canal transportation in the curved portion when compared to PTU system.

• 대한한방내과학회지
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• 제27권3호
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• pp.677-687
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• 2006

Objective : Hypothyroidism is a common disease of the endocrinal system. characterized by fatigue, cold intolerance, bradycardia, and so on. Clinically, Levothyroxine(L-T4) has been usually used for replacement therapy, but it often has side effects. so many hypothyroidism patients wants oriental medical therapy. Zingiberis rhizoma, traditionally has been used in treatment of coldness, fatigue, and bradycardia. In this study. I investigated the therapeutic effects of Zingiberis rhizoma on PTU induced hypothyroidism in rats. Methods : I used two-month-old rats administered PTU and induced with hypothyroidism. After 2 weeks. Zingiberis rhizoma and thyroxine were daily administered, respectively. Body weights was measured every weeks. After 4 weeks, blood samples were taken and analyzed biochemically and T4 and TSH were measured by ELISA kits. Results : In comparison with normal groups, control groups showed hypothyroidism with low T4 and high TSH level. In Zingibris rhizoma administration groups were observed T4 level elevation, this elevation was dependent on the dose of Zingibris rhizoma. Between experimental groups and control groups, there was no difference in TSH level, statistically. Changes of biochemistry were not observed in any experimental groups. Conclusions : These findings suggest that Zingiberis rhizoma makes thyroid cells producing thyroid hormones. There is also a non-toxic effect on the cardiovascular system, liver and kidney function. So, Zingiberis rhizoma should be an effective agents for treating hypothyroidism.

• Medical Lasers
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• 제10권1호
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• pp.37-44
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• 2021

Background and Objectives Hypothyroidism is the most common endocrine disease. On the other hand, there is no treatment that can improve the thyroid function. Low-level laser therapy (LLLT) can improve the cellular activity. The effect of hypothyroidism is not obvious. This study examined the effects of LLLT on the thyroid gland function of a propylthiouracil (PTU)-induced hypothyroidism mouse model. Materials and Methods Twenty-five male ICR mice were distributed into five groups of five animals each: Negative control (none PTU animal) and positive control (PTU animal) of unirradiated animals, and three experimental groups with LLLT (3J, 6J, and 12J). Each mouse was exposed to a distinct dose of a 632-nm laser once a week for three rounds. The positive control group and three LLLT groups were induced into a hypothyroidism state by PTU administration. The animals' thyroid-stimulating hormone and thyroxine levels were measured using an ELISA kit, and their thyroid tissue was harvested and analyzed after sacrifice at the end of the experiment. The hormone level and morphological changes in the tissue of the five groups were compared. Results The thyroid hormone levels in the control group and LLLT groups were similar. On the other hand, the thyroid tissue of the LLLT groups showed some morphological changes that were similar to those of iodine deficiency thyroid. Conclusion LLLT did not affect the thyroid gland function in PTU-induced hypothyroidism mice.

• 농업과학연구
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• 제13권2호
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• pp.210-218
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• 1986

본(本) 실험(實驗)은 thyroxine 및 propylthiouracil의 투여(投與)에 의(依)한 갑상선(甲狀腺)의 기능변화(機能變化)와 아울러 체성장(體成長)에 미치는 영향(影響)을 구명(究明)코저 실시(實施)하였는 바, 25일령(日齡)의 암 흰쥐를 갑상선척출군(甲狀腺剔出群), propylthiouracil 처리군(處理群), Thyroxine 처리군(處理群) 및 정상대조군(正常對照群)의 사개군(四個群)으로 나누어 배치(配置)하고 각군(各群)을 처리후(處理後) 시간경과(時間經過)에 따라 도살(屠殺)하여 갑상선(甲狀腺)의 중량측정(重量測定) 및 조직학적(組織學的) 검색(檢索)과 아울러 체중(體重)의 변화(變化)를 조사(調査)하였다. 1. 갑상선(甲狀腺)의 중량(重量)은 모든 관찰시간(觀察時間)에서 비교군간(比較群間)에 유의성(有意性)이 인정(認定)되었는데 PTU 처리군(處理群)은 정상대조군(正常對照群)에 비(比)하여 높은 중량(重量)을 나타냈고, Thyroxine 처리군(處理群)은 낮은 값을 나타냈다. 2. 갑상선(甲狀腺)의 조직상(組織像)은 PTU 처리군(處理群)에서는 처리(處理) 1주후(週後)부터 여포상피세포(濾胞上皮細胞)가 증식(增殖) 비대(肥大)를 동반(同伴)하는 원주화현상(圓柱化現象)을 나타내기 시작하여 실험기간(實驗期間)이 경과(經過)될 수록 더욱 진행(進行)되는 조직소견(組織所見)을 보였으며, Thyroxine 처리군(處理群)에서는 여포상피세포(濾胞上皮細胞)가 도평화(屠平化)되는 퇴행성(退行性) 변화(變化)가 인지(認知)되었다. 3. 체중(體重)은 처리(處理) 2주후(週後)부터 비교군간(比較群間)에 유의성(有意性)이 인정(認定)되는 변화(變化)를 보였는데 PTU 처리군(處理群)과 갑상선척출군(甲狀腺剔出群)은 정상대조군(正常對照群)에 비(比)하여 낮은 값을 나타냈고 Thyroxine 처리군(處理群)은 높은 체중치(體重値)를 보였다. 그러나, 다중검정결과(多重檢定結果) PTU 처리군(處理群)과 갑상선척출군(甲狀腺剔出群) 상호간(相互間)에는 유의성(有意性)이 인정(認定)되지 않았다.

• Tuberculosis and Respiratory Diseases
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• 제58권1호
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• pp.78-82
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• 2005

그레이브스병으로 진단받고 2년간 PTU 복용 중 폐포 출혈과 ANCA 양성 소견 보여 PTU에 의해 유발 된 ANCA 관련 혈관염으로 진단된 후 PTU 중단과 고용량 스테로이드와 면역 억제제 사용 후 증상 및 방사선학적으로 호전된 증례를 경험하여 문헌고찰과 함께 보고하는 바이다.

• Restorative Dentistry and Endodontics
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• 제42권4호
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• pp.301-308
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• 2017

Objectives: It was aimed to compare the cyclic fatigue resistances of ProTaper Universal (PTU), ProTaper Next (PTN), and ProTaper Gold (PTG) and the effects of sterilization by autoclave on the cyclic fatigue life of nickel-titanium (NiTi) instruments. Materials and Methods: Eighty PTU, 80 PTN, and 80 PTG were included to the present study. Files were tested in a simulated canal. Each brand of the NiTi files were divided into 4 subgroups: group 1, as received condition; group 2, pre-sterilized instruments exposed to 10 times sterilization by autoclave; group 3, instruments tested were sterilized after being exposed to 25%, 50%, and 75% of the mean cycles to failure, then cycled fatigue test was performed; group 4, instruments exposed to the same experiment with group 3 without sterilization. The number of cycles to failure (NCF) was calculated. The data was statistically analyzed by using one-way analysis of variance and post hoc Tukey tests. Results: PTG showed significantly higher NCF than PTU and PTN in group 1 (p < 0.05). Sterilization significantly increased the NCF of PTN and PTG (p < 0.05) in group 2. PTN in group 3 had significantly higher cyclic fatigue resistance than PTN group 4 (p < 0.05). Also, significantly higher NCF was observed for PTG in group 2 than in groups 3 and 4 (p < 0.05). Conclusions: PTG instrument made of new gold alloy was more resistant to fatigue failure than PTN and PTU. Autoclaving increased the cyclic fatigue resistances of PTN and PTG.

• Restorative Dentistry and Endodontics
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• 제41권3호
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• pp.176-181
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• 2016

Objectives: This study aimed to compare two nickel-titanium systems (rotary vs. reciprocating) for their acceptance by undergraduate students who experienced nickel-titanium (NiTi) instruments for the first time. Materials and Methods: Eighty-one sophomore dental students were first taught on manual root canal preparation with stainless-steel files. After that, they were instructed on the use of ProTaper Universal system (PTU, Dentsply Maillefer), then the WaveOne (WO, Dentsply Maillefer). They practiced with each system on 2 extracted molars, before using those files to shape the buccal or mesial canals of additional first molars. A questionnaire was completed after using each file system, seeking students' perception about 'Ease of use', 'Flexibility', 'Cutting-efficiency', 'Screwing-effect', 'Feeling-safety', and 'Instrumentation-time' of the NiTi files, relative to stainless-steel instrumentation, on a 5-point Likert-type scale. They were also requested to indicate their preference between the two systems. Data was compared between groups using t-test, and with Chi-square test for correlation of each perception value with the preferred choice (p = 0.05). Results: Among the 81 students, 55 indicated their preferred file system as WO and 22 as PTU. All scores were greater than 4 (better) for both systems, compared with stainless-steel files, except for 'Screwing-effect' for PTU. The scores for WO in the categories of 'Flexibility', 'Screwing-effect', and 'Feeling-safety' were significantly higher scores than those of PTU. A significant association between the 'Screwing-effect' and students' preference for WO was observed. Conclusions: Novice operators preferred nickel-titanium instruments to stainless-steel, and majority of them opted for reciprocating file instead of continuous rotating system.

• 한국임상수의학회지
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• 제33권5호
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• pp.246-254
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• 2016

The objective of the present study is to determine whether blue honeysuckle lyophilized concentrated powder (BH) has favorable effects on hypothyroidism and related reproductive organ damage. Hypothyroidism was induced by 9 subcutaneous administration of propylthiouracil (PTU) for 28 days. Levothyroxine (LT4)-treated group was intraperitoneally injected with LT4 for the same period, while for BH (125, 250, and 500 mg/kg) or Flos Lonicerae lyophilized aqueous extract (LF, 250 mg/kg)-treated groups, the test materials were orally administrated for 42 days: two weeks before PTU injection and during PTU administration. The changes in serum thyroid hormone levels, serum male sex hormone levels, and testis antioxidant defense system were observed by histopathology of the thyroid gland, epididymis, prostate, and testis. The oral administrations of 125, 250, and 500 mg/kg of BH showed favorable effects compared to LF on hypothyroidism and related damages of reproductive organs through augmentation of the antioxidant defense system in the testis. In conclusion, BH is a promising new potent thyroid gland protecting agent.

• 한국항해학회지
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• 제22권3호
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• pp.51-63
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• 1998

본 논문은 미국내의 다른 터미널 운용구조를 고찰하고, 크레인 사용을 위해서 가장 효과적인 터미널 관리장치유형(ACC, CUP, PTU)을 찾조자 시도하여 연구한 결과이다. 터미널 비교에 사용된 효율을 산정하기 위해서 시간당 순총 크레인 움직임을 사용했다. 가장 효과적인 장치를 찾기 위해서 총 31개 터미널을 비교하여 시도했다. 이 이론에서는 PTU 시설이 가장 효과적인운영장치임을 알게 되었으며, 보기로 든 터널이 너무 적어서 미국내 터미널에 이 결과를 직접적으로 적용하기에는 어려움이 있다.