• The Korean Journal of Zoology
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• v.19 no.1
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• pp.25-32
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• 1976

To observe the changes of mucosubstances of the mucous secreting cells, stomach tissues in frog tadpoles at each stage of metamorphosis were fixed in 10% buffered formalin at $4^{\circ}C$, embedded in paraffin, sectioned to 4 $\mu$m thickness and stained with periodic acid-Schiff(PAS) and alcian blue (AB) of pH 2.5 and pH 1.0. The results obtained were as follows: 1. The reactivities of the surface mucous cells, which exhibited strong PAS-positivity and weak alcianophilia at both pH 2.5 and 1.0, were not changed in metamorphosis stages and the intracellular contents of neutral mucosubstances in the surface mucous cells increased significantly in XXIV and XXV stages of metamorphosis. 2. In the foveolar mucous cells, which appear after metamorphosis XXI, the staining reactivities to PAS, AB of pH 2.5 and 1.0 were the same as that of surface mucous cells during metamorphosis and the alcianophilia were stronger at pH 1.0 than at pH 2.5. 3. THe mucous neck cells, which appear after metamorphosis XXIV, exhibited a strong PAS-positive reaction and weak alcianophilia at metamorphosis XXIV but at metamorphosis XXV weak reactivity to PAS and strong alcianophilia at pH 1.0.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.68-76
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• 2024

To reveal the feeding ecology of Rhynchocypris semotilus, the survey was conducted in Songhyeoncheon, Songhyeon-ri, Hyeonnae-myeon, Goseong-gun, Gangwon-do in April 2022. As a result of analyzing the contents of the stomach using the index of relative importance (IRI), the important prey organisms were mainly Trichoptera (46.6%), Ephemeroptera (27.6%), Diptera (12.6%), Odonata (9.7%), Plecoptera (2.8%), Coleoptera (0.6%), and Hemiptera (0.1%) of Class Insecta, Phylum Arthropoda in that order. As a result of analyzing the trend by calculating the index of relative importance (IRI) for each age, it was found that those born in the same year mainly feed on relatively small Ephemeroptera and Diptera, but the proportion of these gradually decreases as they grow. And the proportion of relatively large Trichoptera and Odonata gradually increased, turning them into the most important food source for those over 3 years old. Additionally, prey size was the smallest at 2.8±2.5 (0.6 to 9.0) mm for individuals born in the same year, but gradually increased to 5.1±6.1 (1.1 to 17.0) mm for individuals born more than 3 years. As a result of examining prey selectivity, Plecoptera (+0.78), Trichoptera (+0.66), (+0.66), Coleoptera (+0.66), and Hemiptera (+0.03) showed positive selectivity, while Amphipoda (-1.00), Ephemeroptera (-0.24), Odonata (-0.13) and Diptera (-0.05) showed negative selectivity.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.182-187
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• 2024

Feeding habits of the large yellow croaker, Larimichthys crocea, was studied using 816 specimens collected by large pair-trawl fishery from June 2021 to May 2022 in the coastal waters of Jeju Island, Korea. The range of total length was 19.8~57.4 cm. Using the IRI, Pisces were mainly prey component constituted 57.5%. Euphausiacea and Macrura were important prey component constituted 23.2% and 18.7%, respectively. There was a significant difference in the change in diet composition by size group. As the L. crocea grew, the feeding rate of Euphausiacea decreased and the feeding rate of Pisces increased. There were also significant differences in the changes in diet composition by seasonal group. The most important prey species for L. crocea in the winter and spring were Pisces, in the summer it was Macrura, and in the fall it was Euphausiacea. As a result of analyzing the feeding relationship between size groups and season groups, L. crocea showed significant differences in the interaction between size groups and season groups.

• Journal of Animal Science and Technology
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• v.66 no.2
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• pp.353-365
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• 2024

Rumen cannulation is a surgical technique used to collect rumen contents from ruminants. However, rumen cannulation surgery may potentially impact the composition of the rumen microbiota. This study aimed to examine the longitudinal alterations in the rumen microbiota composition of Hanwoo steers after cannulation surgery. In this study, eight Hanwoo steers were used; four steers underwent rumen cannulation surgery (cannulation group), while the remaining four were left intact (control group). Rumen samples were collected from all eight steers using the stomach tubing method on the day before surgery (day 0) and on postoperative days 1, 4, 7, 10, 14, 17, 21, 24, and 28, resulting in 80 samples (10 timepoints × 8 animals). The microbiota of all 80 samples were analyzed using 16S rRNA gene amplicon sequencing with Quantitative Insights into Microbial Ecology version 2 (QIIME2). There were no significant differences (p > 0.05) in all major phyla and most major genera representing at least 0.5% of total sequences across all 80 samples between the control and cannulation groups on the preoperative and postoperative days. However, while the alpha diversity indices did not differ (p > 0.05) between the two groups on the preoperative day, they significantly differed (p < 0.05) between the two groups on the postoperative days. Further, the overall microbial distribution based on both unweighted and weighted principal coordinate analysis plots significantly differed (p < 0.05) between the two groups on both the preoperative and postoperative days. Orthogonal polynomial contrasts indicated that major genera and microbial diversity in the cannulation group decreased following surgery but returned to their initial states by postoperative day 28. In conclusion, this study demonstrates that rumen cannulation surgery affects some major taxa and microbial diversity, suggesting that the rumen cannulation method can alter the composition of rumen microbiota in Hanwoo steers.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.57-67
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• 2011

Agaricus brasiliensis, one of edible mushroom belonging to Basidiomycota, has been used for curing gastric ulcer and stomach cancer of human beings and also known to have good inhibitory effects on sarcoma 180 and Ehrlich carcinoma of mice. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were prepared from fruiting body of the mushroom. ${\beta}$-glucan and total protein contents were identify from fractions of edible mushrooms extract. The ${\beta}$-glucan and protein contents of all fractions of the mushrooms ranged from 21.54~32.31% and 0.16~9.34%, respectively. In vitro cytotoxicity tests, crude polysaccharides were not cytotoxic against cancer cell lines such as Sarcoma 180, HT-29, NIH3T3 and RAW 264.7 at the concentration of 10~2000 ${\mu}g/ml$. Intraperitoneal injection with crude polysaccharides exhibited life prolongation effect of 18.8~50.6% in mice previously inoculated with Sarcoma 180. Fr. HW increased the numbers of spleen cell by 1.2 fold at the concentration of 200 ${\mu}g/ml$ compared with control. Fr. MeOH and Na improved the immuno-potentiating activity of B lymphocyte by increasing the alkaline phosphatase activity by 1.6 fold compared with control at the concentration of 50~500 ${\mu}g/ml$. Fr. Na generated 15.9 ${\mu}M$ of nitric oxide (NO) when cultured with RAW 264.7 at the concentration of 200 ${\mu}g/ml$, while lipopolysaccharide, a positive control, produced 3.7 ${\mu}M$. The Fr. NaCl, Fr. HW and Fr. MeOH increased the secretion of TNF-${\alpha}$, IL-$1{\beta}$, Il-2 and IL-6 by 2.2 times compared with the control group. Fr. Na increased the numbers of peritoneal exudate cells by 4 folds at the concentration of 50mg/kg compared with control. Circulating leukocytes increased by 2.7 folds when Fr. HW from A. brasiliensis was inoculated at the concentration of 50 mg/kg body weight. The hematological and blood chemical analysis of the 3 fractions did not show any difference in blood compositions and enzyme activities compared with the control group (p<0.05). Therefore, the experimental results suggested that crude polysaccharides extracted from A. brasiliensis contain antitumor and immuno-potentiating activities against Sarcoma 180 in ICR mice.

• Korean Journal of Food Science and Technology
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• v.5 no.3
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• pp.169-173
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• 1973

Secondary amines and nitrites in various daily foods have been known as the precursors of potent carcinogenic nitroso compound produced in the human stomach when they were ingested simultaneouly in high concentration. In this report, the amounts and distribution of secondary amines and nitrites in Korean daily foods, kim-chi, fishes, fish eggs, sausages, canned fish foods and fish sauces (salted fish) were studied.Nitrite contents were low in most subjected foods except in sausages. Secondary amines showed low contents in kim-chi, fishes, but high in fish sauces, fish eggs and canned fish foods. The result of this study suggested that the possible formation of carcinogenic nitrosamines during manufacturing, storage and cooking of all Korean foods should be studied.

• Journal of Chest Surgery
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• v.30 no.5
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• pp.471-478
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• 1997

Introduction: The use of rabbits as a cardiopulmonary bypass(CPB) animal model is extremely dif%cult mainly due to technical problems. On the other hand, deep hypothermic circulatory arrest(CA) is used to facilitate surgical repair in a variety of cardiac diseases. Although steroids are generally known to be effective in the treatment of cerebral edema, the protective effects of steroids on the brain during CA are not conclusively established. Objectives of this study are twofold: the establishment of CPB technique in rabbits and the evaluation of preventive effect of steroid on the development of brain edema during CA. Material '||'&'||' Methods: Fifteen New Zealan white rabbits(average body weight 3.5kg) were divided into three experimental groups; control CA group(n=5), CA with Trendelenberg position group(n=5), and CA with Trendelenberg position + steroid(methylprednisolone 30 mglkg) administration group(n=5). After anesthetic induction and tracheostomy, a median sternotomy was performed. An aortic cannula(3.3mm) and a venous ncannula(14 Fr) were inserted, respectively in the ascending aorta and the right atrium. The CPB circuit consisted of a roller pump and a bubble oxygenator. Priming volume of the circuit was approximately 450m1 with 120" 150ml of blood. CPB was initiated at a flow rate of 80~85ml/kg/min, Ten min after the start of CPB, CA was established with duration of 40min at $20^{\circ}C$ of rectal temperature. After CA, CPB was restarted with 20min period of rewarming. Ten min after weaning, the animal was sacrif;cod. One-to-2g portions of the following tissues were rapidly d:ssected and water contents were examined and compared among gr ups: brain, cervical spinal cord, kidney, duodenum, lung, heart, liver, spleen, pancreas. stomach. Statistical significances were analyzed by Kruskal-Wallis nonparametric test. Results: CPB with CA was successfully performed in all cases. Flow rate of 60-100 mlfkgfmin was able to be maintained throughout CPB. During CPB, no significant metabolic acidosis was detected and aortic pressure ranged between 35-55 mmHg. After weaning from CPB, all hearts resumed normal beating spontaneously. There were no statistically significant differences in the water contents of tissues including brain among the three experimental groups. Conclusion: These results indicate (1) CPB can be reliably administered in rabbits if proper technique is used, (2) the effect of steroid on the protection of brain edema related to Trendelenburg position during CA is not established within the scope of this experiment.

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.648-657
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• 2008

This research was conducted to investigate the breeding density and seasonal food items of the magpies in Jeju Island and the near-manned islets. The examination of nest distribution to determine breeding density was performed during breeding season from February 2006 to April 2008, and that of food items from May 2006 to February 2008. A total of 2,113 nests were found across Jeju Island, the average density was $1.33\;nest/km^2$, and the magpies were distributed up to 600 meters above the sea level. The nest density was the highest in the central areas of Jeju Island, with 688 nests at $3.61\;nest/km^2$, while that in the eastern areas was the lowest, with 214 nests at $0.66\;nest/km^2$. In terms of the number of nests depending on the height above the sea level, 1,172 nests, which was equivalent to the density of $1.85\;nest/km^2$, was observed below 100m and highest among the intervals of height, but 16 nests found at 500-600m were the lowest, corresponding to $0.20\;nest/km^2$. The number of nests found in the manned islets near Jeju Island was eight in Biyang-do with the density of $15.38\;nest/km^2$, nine in U-do with $1.49\;nest/km^2$, and one in Gapa-do with $1.15\;nest/km^2$, whereas none of nests were observed in Mara-do. The contents of stomach consisted of 17 types of prey sources including countless bones, eggshells, plants, and seed, most of which were the individuals of the order Coleoptera. In spring and summer, the foraging frequency for invertebrate animals such as insects was high, but less than 30% in winter. In contrast, the magpies preyed upon plants and seeds at the frequency of 10% and 30%, respectively, in spring, while the foraging frequencies for both of them were 100% in winter and higher than any of other seasons. Eggshells and bones of birds were also detected infrequently. If the density of the magpies, which may play role as the upper predator within the ecosystem, increases, it would be expected to affect directly the reduction of the number of the species and population of endemic animals such as small birds and reptiles, etc. Therefore, it is considered that long-term monitoring for the density of the magpies and precaution is prerequisite to minimize adverse effects on ecosystem.

• Journal of Nutrition and Health
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• v.43 no.2
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• pp.105-113
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• 2010

Ixeris dentata var. albiflora Nakai, a herbal plant, is often used to make a strong stomach as an antiphlogistic used when dyspepsia and to improve appetite in Korea and China. And also it is used for adult diseases such as diabetes and liver diseases as Korean traditional medicine. In this study, the composition and DPPH radical scavenging activities of the root of Ixeris dentata var. albiflora Nakai and its effects on cell viability on vero and chang cells were investigated. Moisture, crude ash, crude protein and crude lipid were 79.14, 2.49, 8.28 and 2.56 g/100 g respectively. The highest mineral content was K. The major free sugars were glucose, fructose and sucrose. Major fatty acid are linoleic acid, palmic acid and linolenic acid. Major amino acids were glutamic acid, arginine and aspartic acid and the total contents of amino acids were 28.12 mg/g. The methanol extracts were further fractionated with n-hexane, chloroform, ethylacetate, butanol and water to get an active fraction. In addition, cell viabilities in each fraction were determined. Methanol extract, butanol, and aqueous fraction showed strong survival rates in vero cell and chang cell viability test, and hexane, chloroform, and ethylacetate fraction were examined for toxin in a cell. The root of Ixeris dentata var. albiflora Nakai had scavenging activities against DPPH radicals in a dose-dependent assay. Ethylacetate fraction's SC50 was $6.8\{\mu}g/mL$, very strong DPPH radical scavenging activities, but water fraction did not show any activity.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.75-83
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• 1977

Korean native goats were used for meat production test, and summarized resalts are as follows. 1. The amounts of feed consumed for Korean Native Goat were significantly higher at day than at night. 2. The feed intake was decreased and live weight gain was lower for the summer period. 3. The concentrate consumption was increased when poor quality of pasture and native grass. 4. Compared between single bran feeding group$(T_2)$ and mixed grain feeding group$(T_3)$, the roughage consumption were similar in both groups. 5. By the use of feeding standard for feeding of Korean Native Goat, the feed convertion of T.D.N, D.C.P, and M. E were decreased. 6. It is necessary to periodically protect from contamination parasitic such like stomach worm, liver flack, nodula worm disease and coccidiosis. 7. The carcass rates of goat at 11-12 months age were higher in $T_3$ feeding group as 44.56% compared with $T_2$ feeding group as 42.17% and tethering group as 35.1% and also the dressed carcass percentage were 33.89%, 30.25% and 29.92% respectively. 8. By increasing the amouat concentrate feeds, fat content in muscle was increased but moisture and ash contents were decreased. 9. The fat caused unacceptable flavour was about 4 percent of total dressed goat meat. 10. Among the spices, clove and pepper were better to improved meat flavour for sausage and can meat processing 11. It was known that the quality of goat meat was suitable for meat processing.