• 한국분말재료학회지
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• 제31권1호
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• pp.23-29
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• 2024

This study investigates the effect of the microstructure of Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP), a solid electrolyte, on its ionic conductivity. Solid electrolytes, a key component in electrochemical energy storage devices such as batteries, differ from traditional liquid electrolytes by utilizing solid-state ionic conductors. LATP, characterized by its NASICON structure, facilitates rapid lithium-ion movement and exhibits relatively high ionic conductivity, chemical stability, and good electrochemical compatibility. In this study, the microstructure and ionic conductivity of LATP specimens sintered at 850, 900, and 950℃ for various sintering times are analyzed. The results indicate that the changes in the microstructure due to sintering temperature and time significantly affect ionic conductivity. Notably, the specimens sintered at 900℃ for 30 min exhibit high ionic conductivity. This study presents a method to optimize the ionic conductivity of LATP. Additionally, it underscores the need for a deeper understanding of the Li-ion diffusion mechanism and quantitative microstructure analysis.

• 산학경영연구
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• 제11권
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• pp.255-276
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• 1998

본 연구의 목적은 상장기업들이 회계변경을 통해 이익 또는 법인세를 유연화하는가를 알아보고, 회계변경 정보가 주가에 어떠한 영향을 주는가를 분석하는 데 있다. 주가에 영향을 미치는 회계변경 정보로는 법인세절감액, 이익유연화 및 법인세유연화 등이다. 연구결과, 상장기업들은 회계변경을 이익 또는 법인세유연화의 도구로 사용하고 있으며, 이들을 동시에 달성하는 경향이 있음이 밝혀졌다. 그러나 회계변경으로 인한 법인세절감액, 이익유연화 및 법인세유연화 변수는 주가의 변동에는 영향을 미치지 않는 것으로 나타났다. 그러나 비정상수익률을 결산 월부터 이후 3개월간 누적시킨 기간에만 이익유연화 변수는 주가의 변동에 긍정적인 영향을 주지만, 법인세유연화는 부정적인 영향을 주는 것으로 나타났다. 보다 결정적인 결론을 얻기 위해서는 기업의 회계변경에 관한 연구가 많이 이루어져야 할 것으로 판단된다.

• Toxicological Research
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• 제28권2호
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• pp.99-102
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• 2012

Bee venom (Apis mellifera L. BV) has been used as a cosmetic ingredient for anti-ageing, anti-inflammatory and antibacterial functions. The aim of this study was to evaluate the acute toxicity after a single dermal administration of BV, BV was administered to 2 groups of Sprague-Dawley (SD) male and female rats (5 animals/group) at doses of 0 and 1,500 mg/kg body weight (BW). Mortality, clinical signs, body weight changes and gross findings were continually monitored for 15 days following the single dose. There were no unscheduled deaths in any groups during the study period. No BV related clinical signs and body weight changes were observed in any groups during the study period. There were no abnormal gross findings at necropsy on day 15 after the treatment. On the basis of the above results, it was concluded that there were no treatment-related effect on mortality, clinical signs, body weight changes and gross findings in SD rats treated with a single dermal dose of BV at dose of 1,500 mg/kg BW. Therefore, the approximate lethal dose of BV was considered to be over 1,500 mg/kg/day for both sexes of rats. BV may provide a developmental basis for a cosmetic ingredient or external application for topical uses.

• 동의생리병리학회지
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• 제27권3호
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• pp.299-305
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• 2013

This study was to evaluate the single dose toxicity of Arecae Semen (AS) in male and female ICR mice. Aqueous extracts of AS (Yield = 13.15%) were administered as an oral dose of 2,000, 1,000 and 500 mg/kg (body weight) according to the recommendation of Korea Food and Drug Administration (KFDA) guidelines. Animals were monitored for the mortality and changes in body weight, clinical signs and gross observation during 14 days after dosing, upon necropsy; organ weight and histopathology of 12 principle organs were examined. We could not find any mortality, clinical signs, and changes in the body and organ weight except for diarrhea. Diarrhea were observed in all three different dosage groups of male mice, and in 2000 mg/kg groups of female mice within 48hrs after administration. In addition, no AS extract related abnormal gross findings and changes in histopathology of principle organs were detected except for some sporadic accidental findings. Although the 50% lethal dose and approximate lethal dose of AS aqueous extracts in female and male mice were detected as over 2,000 mg/kg - the limited highest dosage recommended by KFDA guidelines. It should be carefully used in clinics because AS may be induced severe digestive tract disorders.

• 대한임상전기생리학회지
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• 제5권2호
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• pp.73-84
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• 2007

This study aims to examine changes from differences in the lumbar scoliosis angle and iliac crest height due to abnormal and habitual posture shown in unilateral weight load at standing posture and suggest data for preventing and treating lumbago. The subjects of this study are 16 lumbago patients between twenties and forties with chronic lumbago over six months, but without neurological symptoms. As a result of photographing front and back with three conditions such as weight load on both sides and left or right unilateral weight load posture in order to examine changes of lumbar scoliosis and iliac crest according to changes of posture at unilateral weight load, while scoliosis angle and iliac crest height by habitual unilateral support were increased, those by opposite support were decreased. In conclusion, it was found that habitual unilateral weight load may cause continuous distortion of spinal angle and change of iliac crest height and these may be a factor of lumbago. Therefore, if habitual unilateral weight load state is kept continuously, distortion of lumbar angle and iliac crest height may be greater and common efforts to change habitual unilateral weight load are needed.

• Biomolecules & Therapeutics
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• 제15권2호
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• pp.127-132
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• 2007

The object of this study was to evaluate the acute toxicity of lyophilized water extract of Radix Araliae Cordatae (RA) in male and female mice. The extract was administered to female and male ICR mice as an oral dose of 2000 mg/kg (body wt.) according to the recommendation of KFDA Guidelines. Animals were monitored for the mortality and changes in body weight, clinical signs and gross observation during 14 days after dosing, upon necropsy, organ weight and histopathology of 12 principle organs were examined. As results, we could not find any mortality, clinical signs, changes in the body weight and gross findings except for increases of hypertrophy of lymph nodes in male RA extracts-dosing group. In addition, no RA extracts-treatment related abnormal changes in the organ weight and histopathology of principle organs except for some sporadic accidental findings. The results obtained in this study suggest that the RA extracts does not cause any toxicological signs. The LD$_{50}$ and approximate LD of RA extracts in both female and male mice were considered as over 2000 mg/kg.

• 약학회지
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• 제38권6호
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• pp.756-762
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• 1994

To investigate the acute toxicity of Elfvingia applanata$(P_{ers})K_{ARST}$, it was extracted with hot water. EA, the aqueous extract from the carpophores of E. applanata, was lyophilized and a dark brownish powder was obtained. The acute toxicity of EA was investigated in ICR mice of both sexes. Five groups of mice were administered orally and intraperitoneally with 375, 750, 1,500, 3,000, 6,000 mg/kg(p.o.) and 312.5, 625, 1,250, 2,500, 5,000 mg/kg (i.p.) of EA Abnormal clinical signs related to EA were not observed and no deaths occurred. $LD_{50}$ values administered orally and intraperitoneally were evaluated to be over 6,000 mg/kg and over 5,000 mg/kg, respectively. Gross finding of necropsy revealed no evidence of specific toxicity related to EA. There were no significant changes in body weights, serum biochemical values and histopathological changes compared with control group.

• 대한예방한의학회지
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• 제15권2호
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• pp.21-38
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• 2011

Objective : This study was to evaluate the single dose toxicity of Bojungikki-tang(Buzhongyiqi-tang, BJIKT) in male and female mice. Method : Aqueous extracts of BJIKT were administered to female and male ICR mice as an oral dose of 2,000, 1,000 and 500 mg/kg (body weight) according to the recommendation of Korea Food and Drug Administration (KFDA) Guidelines. Animals were monitored for the mortality and changes in body weight, clinical signs and gross observation during 14 days after dosing, upon necropsy ; organ weight and histopathology of 12 principle organs were examined. Results : we could not find any mortality, clinical signs, and changes in the body and organ weight. In addition, no BJIKT-treatment related abnormal gross findings and changes in histopathology of principle organs were detected except for some sporadic accidental findings. Conclusion : The results obtained in this study suggest that the 50% lethal dose and approximate lethal dose of BJIKT aqueous extracts in both female and male mice were considered as over 2,000 mg/kg, the limited highest dosage recommended by KFDA Guidelines, and can be safety used in clinics.

• Biomolecules & Therapeutics
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• 제15권4호
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• pp.245-251
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• 2007

The object of this study was to evaluate the single dose toxicity of Kong-Jin-Dan (KJD), a polyherbal formula in male and female mice. KJD was administered to female and male ICR mice as an oral dose of 2000, 1000 and 500 mg/kg (body wt.) according to the recommendation of KFDA Guidelines. Animals were monitored for the mortality and changes in body weight, clinical signs and gross observation during 14 days after dosing, upon necropsy, organ weight and histopathology of 12 principle organs were examined. As results, we could not find any mortality, clinical signs, and changes in the body and organ weight except for increases of lymphoid organ weights in KJD-dosing groups. These increases of lymphoid organ weights considered that related to the immune modulate effect of KJD not toxicological signs. In addition, no KJD-treatment related abnormal gross findings and changes in histopathology of principle organs were detected except for some sporadic accidental findings. The results obtained in this study suggest that the KJD does not cause any toxicological signs. The $LD_{50}$ and approximate LD of KJD extracts in both female and male mice were considered as over 2000 mg/kg.

• Biomolecules & Therapeutics
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• 제4권4호
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• pp.354-363
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• 1996

This study was conducted to investigate the repeated dose toxicity of DA-9601, an antiulcer agent of Artemisia app. extract, in rats. DA-9601 was administered orally once a day for 4 weeks to 10 males and 10 females per group at doses of 0(vehicle control), 125, 500 or 2000 mg/kg/day. Throughout the study, no treatment-related deaths and clinical signs were observed. In female rats receiving 125 mg/kg of DA-9601, water consumption increased slightly on day 4, 11 and 25. Hematological examination showed a decrease of MCV and an increase of PLT in male rats at the doses of 500 and 2000 mg/kg groups. Blood biochemistry revealed slight decreases of cholesterol, BUN and Na in male rats and decreases of total bilirubin and creatinine and slight increases of globulin and Cl in female rats. The organ weights at the end of 4 weeks showed slight changes in some organs of treated groups. But, all these changes were not considered to be of toxicological importance, because they did not show dose-response relationship and relevance to gross and microscopic findings. Histopathologically, abnormal treatment-related changes were not observed in any organ and target organs were not detected. On the basis of these results, the NOAEL(no-observed-adverse-effect level) of DA-9601 was estimated to be more than 2000 mg/kg/day under the conditions tested.