• 한국수산과학회지
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• 제32권5호
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• pp.593-600
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• 1999

우리나라 전 연안의 조간대에 분포하고 있는 총알고둥을 대상으로 생존, 성장, 호흡, 배설에 미치는 유기주석, 수은 및 카드뮴의 만성저해성 연구를 통하여, 오염으로 인한 독성과 그에 따른 내성등을 생물학적 방법을 이용하여 조사하였다. 수온 $23^{\circ}C$에서 80일 동안 TBTCl, Hg 및 Cd의 각 실험농도에 폭로시킨 총알고둥의 생존율은 TBTCl, 0.9$\mu$g/$\ell$에서 $80\%$, Hg, 200$\mu$g/$\ell$에서 $25\%$, 그리고 Cd, 100$\mu$g/$\ell$에서는 $45\%$였다. 각 실험농도에 폭로된 총알고둥의 일일 평균 성장률은 대조구에서 0.023mm/day였으며, TBTCl의 경우는 0.1 $\mu$g/$\ell$에서 0.019mm/day로 $17.39\%$, 0.9 $\mu$g/$\ell$에서는 0.014 mm/day로 $39.13\%$ 감소하였으며, Hg의 경우는 50 $\mu$g/$\ell$에서 0.015 mm/day로 $34.78\%$, 200 $\mu$g/$\ell$에서는 0.008mm/day으로 $65.22\%$ 감소하였다. 그리고 Cd의 경우는 5$\mu$g/$\ell$에서 0.017 mm/day로 $26.09\%$, 100 $\mu$g/$\ell$에서는 0.008 mm/day으로 $65.22\%$ 감소하였다. TBTCl, Hg 그리고 Cd의 각 저해농도에 폭로시킨 총알고둥의 호흡 및 질소 배설률은 폭로시간의 경과에 따라 대체로 폭로전반에는 감소하다가 다시 증가하는 경향을 보였다. 각 오염원에 따른 조직학적 변화양상은 TBTCl에서 아가미, Hg에서는 소화관 그리고 Cd의 경우에는 발 근육층부분에서 가장 크게 나타났다.

• The Plant Pathology Journal
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• 제15권4호
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• pp.210-216
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• 1999

TREGRO, a computer simulation model of individual tree growth, was applied to estimate ozone ($\textrm{O}_3$) effects on aspen(Populus tremuloides) growth under ambient and 1.7 times ambient $\textrm{O}_3$ of Seoul in 1996. The three highest $\textrm{O}_3$ (Kuui-dong, Ssangmun-dong, Sungsoo-dong) and the two lowest $\textrm{O}_3$ sites (Mapo-dong, Namgajwa-dong) were evaluated. The current ambient $\textrm{O}_3$ did not affect aspen growth compared to simulation without $\textrm{O}_3$. The only effect was 6.6 percent of total assimilated carbonloss at Ssangmun-dong where the level of $\textrm{O}_3$ was greatest among the 21 sites examined. Decrease as much as 50 percent of total carbon gain was calculated at 1.7 times ambient $\textrm{O}_3$ of the three highest sites. The carbon loss by $\textrm{O}_3$ came from biomass of tissues and total nonstructural cabron (TNC) such as starch and sugar. The most sensitive fraction was TNC and the next was root biomass. Foliage mass was not affected by $\textrm{O}_3$. Structural biomass loss was at best 1 to 3 percent at 1.7 times ambient $\textrm{O}_3$ at the two lowest sites. The daily carbon simulation was affected by $\textrm{O}_3$ mainly during Growth Period 4 (Jul. 21-Oct. 26). Correlations between site, dose, and the simulated responses of aspen (tissue biomass, TNC, respiration, and senescence) ranged from -0.703 to -0.973 depending on the plant responses. The ozone effects on poplar in Seoul are not severe currently, but are probably measurable at Ssangmun-dong. However, severe $\textrm{O}_3$ effects on biomass would occur if $\textrm{O}_3$ levels increase to 1.7 times ambient $\textrm{O}_3$ in Seoul. In addition, v could weaken the trees thus increasing susceptibility to pathogens or insects.

• 농업과학연구
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• 제41권4호
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• pp.291-298
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• 2014

Plastic film houses are directly associated with increases in plant growth and yield of vegetable crops through a year round cultivation, however, at the same time temperature stresses are one of fates which are difficult to avoid during crop growth. The objective of this study was to examine the translocation and distribution of minerals (N, P, K) and carbohydrates as well as seasonal fluctuation of mineral uptake and carbohydrate production in cucumber plant grown under moderately high temperature. The temperature treatments consisted of 2-layers film houses (optimal temp.) and 3-layers (high temp.). Shoot growth of cucumber plants were linearly increased until 14 weeks after transplanting (WAT) without any significant difference between both temperatures, and the slowdown was observed from 16 WAT. The level of soluble sugar and starch was slightly greater in optimal temperature compared to the high. Cumulative accumulation of soluble sugar was significantly different before and after 12 WAT in both treatments, whereas starch level represented a constant increase. Monthly production of soluble sugar reached the peak between 12 to 16 WAT, and starch peaked between 4 to 8 WAT and 12 to 16 WAT. Total uptake of N, P and K in optimal and high temperature conditions was $18.4g\;plant^{-1}$ and 17.6 for N, 4.7 and 5.1 for P, and 37.7 and 36.2 for K, respectively, and the pattern of monthly N uptake between optimal and high temperatures was greater in early growth stage, whereas was greater in mid growth stage in both P and K. Thus, this study suggests that moderately high temperature influences much greater to photosynthesis and carbohydrate production than plant biomass and mineral uptake. On the basis of the present result, it is required to indentify analysis of respiration rates from plant and soil by constantly increasing temperature conditions and field studies where elevated temperatures are monitored and manipulated.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.428-437
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• 2007

The potential for humic substances to serve as terminal electron acceptors in microbial respiration and the effects of humic substances on microbial azoreduction were investigated. The dissimilatory azoreducing microorganism Shewanella decolorationis S12 was able to conserve energy to support growth from electron transport to humics coupled to the oxidation of various organic substances or $H_2$. Batch experiments suggested that when the concentration of anthraquinone-2-sulfonate (AQS), a humics analog, was lower than 3 mmol/l, azoreduction of strain S12 was accelerated under anaerobic condition. However, there was obvious inhibition to azoreduction when the concentration of the AQS was higher than 5 mmol/l. Another humics analog, anthraquinone-2-sulfonate (AQDS), could still prominently accelerate azoreduction, even when the concentration was up to 12 mmol/l, but the rate of acceleration gradually decreased with the increasing concentration of the AQDS. Toxic experiments revealed that AQS can inhibit growth of strain S12 if the concentration past a critical one, but AQDS had no effect on the metabolism and growth of strain S12 although the concentration was up to 20 mmol/l. These results demonstrated that a low concentration of humic substances not only could serve as the terminal electron acceptors for conserving energy for growth, but also act as redox mediator shuttling electrons for the anaerobic azoreduction by S. decolorationis S12. However, a high concentration of humic substances could inhibit the bacterial azoreduction, resulting on the one hand from the toxic effect on cell metabolism and growth, and on the other hand from competion with azo dyes for electrons as electron acceptor.

• 한국수산과학회지
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• 제36권1호
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• pp.39-43
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• 2003

넙치의 생존, 성장 및 대사에 미치는 카드뮴의 만성적 독성을 파악하기 위하여 6주 동안 여러 가지 카드뮴 농도에 노출시켜 실험을 실시하였다. 넙치의 생존율은 카드뮴농도 980 ${\mu}g/L$에서 유의한 감소를 나타냈다. 넙치의 성장률과 사료효율은 카드뮴농도가 증가할수록 감소를 하여 210 ${\mu}g/L$ 이상의 농도에서는 대조구에 비하여 유의한 감소를 나타냈다. 넙치의 대사율은 카드뮴농도 90, 210, 450, 980 ${\mu}g/L$에서 대조구보다 각각 3.3, 18.3, 30.0, $50.1\%$가 저하하여 210${\mu}g/L$ 이상의 농도에서는 유의한 감소를 나타냈다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권9호
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• pp.1276-1284
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• 2012

A 12-wk experiment was conducted to examine the hematological changes, survival, and respiratory exchange in the olive flounder, Paralichthys olivaceus, during starvation. The growth, survival and respiratory exchange rates of the starved group were lower than those of the fed group during the experiment. Blood analysis, including hematocrit, hemoglobin, red blood cells, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and mean corpuscular volume, did not differ significantly (p>0.05) between the fed and starved groups at the end of the experiment. There were no significant differences in plasma cortisol, glucose, $Na^+$, $Cl^-$, $K^+$, or aspartate aminotransferase between the fed and starved groups (p>0.05). Alanine aminotransferase levels were higher in the starved group than in the fed group, whereas plasma osmolality was lower in the starved group than in the fed group. It was shown that starved fish had various problems after four weeks, which did not occur in the fed group. Long-term starvation is infrequent in aquaculture farms. However, starvation studies of this kind are very useful for a basic understanding of how physiological changes affect fish health, life expectancy, and growth.

• Journal of Plant Biology
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• 제14권4호
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• pp.5-13
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• 1971

Pot and paddy field tests were conducted to study red discoloration of rice var. IR 667 leaves with reference to the leading Korean native variety Jinhung and Paldal, with the following results: 1. Minor elements such as Mn, Fe, B, Al, Ca and Si had no influence on the discoloration, but a supply of various soluble nitrogen compounds completely restricted it. The more prosperous the growth of IR 667 with nitrogen, the more severe the discoloration appears when nitrogen absorptin becomes limited. 2. Chlorotic pigments extracted from both IR 667 and Jinhung were compared spectrophotometrically, and found to have different spectral peaks. IR 667 had peak closer to red than Jinhung, indicating the characteristic of the variety. IR 667 was observed to be more sensitive to nitrogen deficiency than Jinhung or the other japonica variety. 3. It was concluded that all the factors limiting nitrogen supply for IR 667 growth, such as low nitrogen application, restriction of root respiration (low temperature, poor drainage, toxic gases or substances in the root zone, etc.) and pest injuries, would result in the appearance of the so-called red discoloration, because of the reduction in nitrogen uptake. Since, the discoloration of IR 667 is varietal characteristic when grown in Korea, control of it may be beneficial cultural practice in increasing grain yield, although the increased succeptibility to pests and a drop in the rate of maturity due to relatively high nitrogen level in the leaves may result in an unexpected drop in yield. It is anticipated that further exploration conducted from practical point of view will establish the relatioknships between the extent of red discoloration, nitrogen availability and grain yield in IR 667.

• Journal of Ginseng Research
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• 제8권1호
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• pp.65-74
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• 1984

This experiment was carried out to study the effects of light intensity and soil water regimes on the growth of ginseng seedling. The results were as follows: 1. The maximum light intensity and optimum temperature in 1,le photosynthesis of ginseng seedling were 10,000 lux and 23 $^{\circ}C$. Respiration rate was increased at high temperature. 2. Air and soil temperature under the shading were increased as the increase of light intensity but soil water contents were decreased as the increase of light intensity, whereas air and soil temperature were decreased as the increase of precipitation under the shade b5: soil water contents were increased as the increase of precipitation under the shade. 3. The higher the transmittance of the shade, the greater the specific leaf weight (S.L.W.) and stomatal density. In contrast, however, the contents of total chlorophyll, chlorophyll a and b, and stomatal length was decreased. There was no any significant difference light intensity of the a/b ratio of chlorophyll. 4. The highest photosynthesis was occurred in ginseng leaves grown under the shade 5% L.T.R. and net photosynthesis rates increased with increasing soil water contents. 5. Optimum condition for usable seedling yield were 5% L.T.R. and 3.3% precipitation under the shade. Useless seedling increased with increasing precipitation under the shade.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.737-741
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• 2014

Background: In recent years a wide variety of flavonoids or polyphenolic substances have been reported to possess substantial anti-carcinogenic and antimutagenic activities. Grape proanthocyanidins (GPC) are considered as good examples for which there is evidence of potential roles as anti-carcinogenic agents. Methods: A xenograft model was established using H22 cells subcutaneously injected into mice and used to assess different concentrations of grape proanthocyanidins (GPC) and Endostar. Treatments were maintained for 10 days, then levels of vascular endothelial growth factor (VEGF) and microvessel density (MVD) were examined by immunohistochemistry, while VEGF mRNA was determined by real-time PCR in tumor tissue. Results: The expression of MVD and VEGF decreased gradually as the concentration of GPC increased.There was a significant positive correlation between MVD and VEGF. Conclusions: These results suggest that GPC restrains the growth of tumor, possibly by inhibiting tumour angiogenesis.

• 한국식품영양과학회지
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• 제19권1호
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• pp.1-12
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• 1990

To investigate effects of ethanol and dietary fat on growth and bichemical indices of liver tissue and blood in rats 40 male rats of Sprague-Dawley wtrain weighing about 160g were divided into 5 groups (low-fat diet group ethanol-administered low-fat diet group high-fat diet group ethanol-administered high-fat diet group and commercial diet group) and fed expe-rimental diets for 8 weeks. Ethanol-administered groups consumed ethanol corresponding to 22 cal% which was considered as moderate drinking. Neither the ethanol intake nor the dietary fat level affected calorie intake. Nonetheless the low-fat diet group with ethanol had the lowest growth rate and 2-fold increase in the concentration of plasma triglyceride. There was no effect of ethanol and dietary fat level on contents of protein lipid and lipid composition of liver tissue. The level of lipid peroxide of liver tissue tended to be increased by ethanol intake but the increase was statistically insignificatnt. The low-fat ethanol group had lowered hepatic mitochondrial respiration rate and deformed structure of mitochondria of hepatocytes.