검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 9

        4.
        2017.10 구독 인증기관·개인회원 무료
        This study was conducted to investigate the temperature and accumulated temperature of Lentinula edodes strains from primordial occurrence to fruit body maturity. The experimental strains were Sanjo 108 (high temperature type), Sanjo 302 (middle temperature type) and Sanjo 502 (low temperature type). When the Sanjo 108 and Sanjo 302 occurred, the daily mean temperature inside the L. edodes inoculated logs was 17.9 ~ 20.5 °C, which was lower than air temperature by 0.7 ~ 1.15 °C. When the Sanjo 502 occurred, the daily mean temperature inside the L. edodes inoculated logs was 3.6 ~ 16.6 °C, which was lower than air temperature by 0.1 ~ 0.7 °C. The difference between the maximum and the minimum temperature when the fruit body occurred was 4.4 °C inside the inoculated logs and 6.9 °C in the air temperature in Sanjo 108 and Sanjo 302, and in Sanjo 502 was 5.5 °C inside the inoculated logs and 9.1 °C in the air temperature. The number of days from primordial occurrence to fruit body maturity in Sanjo 108, Sanjo 302 and Sanjo 502 was 3.9 days, 5.1 days and 10.6 days, and accumulated temperatures of these strains were 104.9 °C, 129.2 °C and 141.4 °C, respectively. The number of days and accumulation temperatures were 518 days and 8,361 °C in Sanjo 108, 444 days and 6,475 °C in Sanjo 302, and 560 days 9,263 °C in Sanjo 502.
        5.
        2017.10 구독 인증기관·개인회원 무료
        The purpose of this study was to understand the effects of mushroom occurrence by forest thinning in the Pinus koraiensis stand. The leaf area index, air temperature and relative humidity, soil water content, and amount of throughfall were measured in the P. koraiensis stand. The more throughfall of 72 mm / year and about 1 °C higher soil temperature were observed in the P. koraiensis stand than non-treatment stand. Relative humidity and soil water content were positively correlated with the occurrence of mushrooms in the P. koraiensis stand. The correlation coefficient of throughfall and ectomycorrhizal mushrooms was 0.93 in the thinned stand of P. koraiensis. 6 less species of ectomycorrhizal mushrooms and 7 more species of saprophytic mushrooms were observed in the thinned stand than in the non-treatment stand of P. koraiensis. Suillus pictus, an ectomycorrhizal mushroom, was found in a distribution of 100 pieces in the non-treatment stand and 69 pieces in the thinned stand of P. koraiensis. But the species diversity index of ectomycorrhizal mushrooms was 0.823 in the non-treatment stand and 0.911 in the thinned stand of P. koraiensis. In conclusion, forest thinning increased throughfall by decreased crown density. Accordingly it increased the number of ectomycorrhizal mushrooms. An increase of felled trees in the forest thinned sites caused an increase of saprophytic mushrooms.
        7.
        2018.03 KCI 등재 서비스 종료(열람 제한)
        In the present study, we employed Hershberger assay to determine possible androgenic or antiandrogenic activities of three di-2-ethylhexyl phthalate (DEHP) substitute candidates. The assay was carried out using immature castrated Sprague–Dawley male rats. After 7 days of the surgery, testosterone propionate (TP, 0.4 mg/kg/day) and test materials (low dose, 40 mg/kg/day; high dose, 400 mg/kg/day) were administered for 10 consecutive days by subcutaneous (s.c.) injection and oral gavage, respectively. Test materials were DEHP, 2-ethylhexyl oleate (IOO), 2-ethylhexyl stearate (IOS) and triethyl 2-acetylcitrate (ATEC). The rats were necropsied, and then the weights of five androgen-dependent tissues [ventral prostate, seminal vesicle, coagulating glands, levator ani-bulbocavernosus (LABC) muscle, paired Cowper’s glands, and glans penis] and four androgen-insensitive tissues (kidney, adrenal glands, spleen and liver) were measured. All test materials including DEHP did not exhibit any androgenic activity in the assay. On the contrary, antiandrogen-like activities were found in all test groups, and the order of the intensity was ATEC < DEHP < ISO < IOO in the five androgen-sensitive tissues. There was no statistical difference between low dose treatment and high dose treatment of all replacement candidate groups. In DEHP groups, high dose treatment exhibited significant weight gains in LABC and Glan Penis. There was no statistical difference in androgen-insensitive tissue measurements. Since the effects of ATEC treatment on the accessory sex organs were much less or not present at all when compared to those of DEHP, ATEC could be a strong candidate to replace DEHP. IOO treatment brought most severe weight reduction in all of androgen-sensitive tissues, so this material should be excluded for further screening of DEHP substitute selection.
        8.
        2017.12 KCI 등재 서비스 종료(열람 제한)
        Bisphenol-A(BPA) is a member of alkylphenol family, and shows adverse effects including reduced fertility, reproductive tract abnormalities, metabolic disorder, cancer induction, neurotoxicity and immunotoxicity. In the present study, we conducted Hershberger assay to evaluate whether the two candidates to replace BPA have androgenic or antiandrogenic activity. The assay was carried out using immature castrated Sprague–Dawley male rats. After 7 days of the surgery, testosterone propionate (TP, 0.4 mg/kg/day) and test materials (low dose, 40 mg/kg/day; high dose, 400 mg/kg/day) were administered for 10 consecutive days by subcutaneous (s.c.) injection and oral gavage, respectively. Test materials were BPA, isosorbide (ISO) and cyclohexanedimethanol (CHDM). The rats were necropsied, and then the weights of five androgen-dependent tissues [ventral prostate, seminal vesicle, levator ani-bulbocavernosus (LABC) muscle, paired Cowper’s glands, and glans penis] and three androgen-insensitive tissues (kidney, spleen and liver) were measured. All test materials including BPA did not exhibit any androgenic activity in the assay. On the contrary, antiandrogen-like activities were found in all test groups, and the order of the intensity was CHDM > BPA > ISO in the five androgen-sensitive tissues. There was no statistical difference between low dose treatment and high dose treatment of BPA group as well as ISO group. In CHDM group, high dose treatment exhibited most severe weight reduction in all measured tissues. There was no statistical difference in androgen-insensitive tissue measurements, except BPA groups. Since the effects of ISO treatment on the accessory sex organs were much less or not present at all when compared to those of BPA, ISO could be a strong candidate to replace BPA. CHDM treatment brought most severe weight reduction in all of androgen-sensitive tissues, so this material should be excluded for further screening of BPA substitute selection.
        9.
        2017.08 서비스 종료(열람 제한)
        Nonylphenols (NP) are used in manufacturing antioxidants and lubricating oil additives, which are considered to be as potent endocrine disruptor. The aim of this study was to examine the effects of NP on reproductive system in adult male mice. Mice were divided into 4 groups; (1) tap water (CON group), (2) 50 μg/L (NP50), (3) 500 μg/L (NP500) and (4) 5000 μg/L (NP5000) of NP via the drinking water for 4 weeks. Mice were sacrificed and the reproductive organ weights were measured. The caudal epididymal sperms were count to assess the toxicity on germ cells. Histopathological changes of tissues were observed by using hematoxylin/eosin staining. The weights of testis in NP5000 group were significantly lighter than those in CON group (104.9±2.9 mg vs 90.7±5.1 mg, p<0.05). And weights of epididymis significantly increased in NP500 group (44.2±2.6 mg vs 54.42±3.44 mg, p<0.05). As concentration of NP increased, the number of sperms significantly decreased (NP50 and NP500, p<0.01; NP5000, p<0.001). In histopathological analyses, the sperms in seminiferous tubules showed a concentration-dependent decrease in mice treated with NP. In epididymis, treatment with NP resulted in empty space and the reduced sperm numbers in dose-dependent manner. Our results confirmed the dose-dependent decrease in the number of sperm and histopathological abnormality of testis and epididymis in mice exposed from 50 μg/L to 5000 μg/L of NP for 4 weeks. The present study suggests that oral exposure of NP might have negative effects on reproductive function, particularly on germ cells, in adult male mice.