• Title/Summary/Keyword: 주간(柱間)

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Effects of Dietary Fats and Oils On the Growth and Serum Cholesterol Content of Rats and Chicks (섭취(攝取) 지방(脂肪)의 종류(種類)가 흰쥐와 병아리의 성장(成長) 및 혈청(血淸) Cholesterol 함량(含量)에 미치는 영향(影響))

  • Park, Kiw-Rye;Han, In-Kyu
    • Journal of Nutrition and Health
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    • v.9 no.2
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    • pp.59-67
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    • 1976
  • A series of experiment was carried out to study the effect of commonly used dietary fat or oils on the growth, feed efficiency, nutrient utilizability, nitrogen retention and serum cholesterol of rats and chicks fed various fat or oils at the level of 10% during 12 weeks of experimentation. Fat and oils used in this experiment were also analyzed for the composition of some fatty acids. The main observations made are as follows: 1. All groups received fat or oils gained more body weight than unsupplemented control group except chicks fed fish oil and rapeseed oil although no statistical significance was found between treatments. It was found that body weight gain achieved by the rats fed soybean oil, rapeseed oil, animal fat or corn oil was much greater than other group and that achieved by the chicks fed corn oil and animal fat was greater than other vegetable oil groups, although no statistical significance was found among treatments. 2. Feed intake data indicated that corn oil group of both rats and chicks consumed considerably more feed than other groups. Whereas feed intake of fish oil groups was the lowest among the experimental animals indicating that fish oil might contain unfavorable compound that depresses the palatability. In feed efficiency, soybean oil group of rats and corn oil group of chicks were significantly better than other experimental groups. In general, addition of fat or oils in the diet improved feed effeciency of diet. 3. Nutrient utiIizabiIity and nitrogen retention data showed that fat in the experimental diet containing 10% fat or oils was absorbed better than crude fat in control diet. It was also found that there was no significant difference in nitrogen retention among treatment. 4. Liver fat content of rapeseed oil group was much higher than that of control group and other group. It was also noticed that feeding more polyunsaturated fatty acids resulted in higher content of Iiver fat. 5. Present data indicated that serum cholesterol content of rapeseed oil and sesame oil group of rat was the higher than that of control group. Serum cholesterol content of animal fat group of chicks was higher than other group. It was interesting to note that serum cholesterol content of chicken was higher than that of rats?regardless of the kind of oils received. 6. Analytical data revealed that fatty acid composition of vegetable oil was composed mainly of oleic acid and linoleic acid, whereas animal fat and fish oil were composed of saturated fatty acid such as, myristic and palmitic acid. It should be mentionted that the perilla oil contained a very large amount of linolenic acid (58.4%) comparing with that in order vegetable oils. Little arachidonic acid was detected in vegetable oil, whereas none in animal fat and. fish oil.

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Studies on the Physiological Chemistry of Seed Development in Ginseng Seed (인삼식물의 종자발육 과정에 있어서의 생리화학적 연구)

  • Hee-Chun Yang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.17
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    • pp.115-133
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    • 1974
  • This study was done on the metabolism of chemical components during the seed development of ginseng. The changes of the chemical components were inspected in the following periods: from the early stage of flower organ formation to flowering time, from the early stage of fruiting to maturity, during the moisture stratification before sowing. From flower bud forming stage to meiosis stage, the changes in the fresh weight, dry weight, contents of carbohydrates, and contents of nitrogen compounds were slight while the content of TCA soluble phosphorus and especially the content of organic phosphorus increased markedly. From meiosis stage to microspore stage the fresh and dry weights increase greatly. Also, the total nitrogen content increases in this period. Insolub]e nitrogen was 62-70% of the total nitrogen content; the increase of insoluble nitrogen seems to have resulted form the synthesis of protein. The content of soluble sugar (reducing and non-reducing sugar) increases greatly but there was no observable increase in starch content. In this same period, TCA soluble phosphorus reached the maximum level of 85.4% of the total phosphorus. TCA insoluble phosphorus remained at the minimum content level of 14.6%. After the pollen maturation stage and during the flowering period the dry weight increased markedly and insolub]e nitrogen also increased to the level of 67% of the total nitrogen content. Also in this stage, the organic phosphorus content decreased and was found in lesser amounts than inorganic phosphorus. A rapid increase in the starch content was also observed at this stage. In the first three weeks after fruiting the ginseng fruit grows rapidly. Ninety percent of the fresh weight of ripened ginseng seed is obtained in this period. Also, total nitrogen content increased by seven times. As the fruits ripened, insoluble nitrogen increased from 65% of the total nitrogen to 80% while soluble nitrogen decreased from 35% to 20%. By the beginning of the red-ripening period, the total phosphoric acid content increased by eight times and was at its peak. In this same period, TCA soluble phosphorus was 90% of total phosphorus content and organic phosphorus had increased by 29 times. Lipid-phosphorus, nucleic acid-phosphorus and protein-phosphorus also increased during this stage. The rate of increase in carbohydrates was similar to the rate of increase in fresh weight and it was observed at its highest point three weeks after fruiting. Soluble sugar content was also highest at this time; it begins to decrease after the first three weeks. At the red-ripening stage, soluble sugar content increased again slightly, but never reached its previous level. The level of crude starch increased gradually reaching its height, 2.36% of total dry weight, a week before red-ripening, but compared with the content level of other soluble sugars crude starch content was always low. When the seeds ripened completely, more than 80% of the soluble sugar was non-reducing sugar, indicating that sucrose is the main reserve material of carbohydrates in ginseng seeds. Since endosperm of the ripened ginseng seeds contain more than 60% lipids, lipids can be said to be the most abundant reserve material in ginseng seeds; they are more abundant than carbohydrates, protein, or any other component. During the moisture stratification, ginseng seeds absorb quantities of water. Lipids, protein and starch stored in the seeds become soluble by hydrolysis and the contents of sugar, inorganic phosphorus, phospho-lipid, nucleic acid-phosphorus, protein phosphorus, and soluble nitrogen increase. By sowing time, the middle of November, embryo of the seeds grows to 4.2-4.7mm and the water content of the seeds amounts to 50-60% of the total seed weight. Also, by this time, much budding material has been accumulated. On the other hand, dry stored ginseng seeds undergo some changes. The water content of the seeds decreases to 5% and there is an observable change in the carbohydraes but the content of lipid and nitrogen compounds did not change as much as carbohydrates.

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The Results of Hvperfractionated Radiation Therapy Combined with Taxol for Paraaortic Node Recurrence in Cervix Cancer (대동맥주위 림프절에 재발된 자궁경부암에서 Taxol을 병행한 과분할 방사선치료의 결과)

  • Kim, Jun-Sang;Jang, Ji-Young;Kim, Jae-Sung;Kim, Sam-Yong;Cho, Moon-June
    • Radiation Oncology Journal
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    • v.18 no.1
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    • pp.27-31
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    • 2000
  • Purpose : The aim of this study was to investigate treatment results, toxicity and efficacy of hypefractionated radiation therapy combined with paclitaxel for paraaortic node recurrence in cervix cancer. Materials and Methods: Between September 1997 to March 1999, 12 patients with paraaortic node recurrence in cervix cancer who previously received radical or postoperative radiotherapy were treated with hypefractionated radiation therapy combined with paclitaxel. Of these, 2 patients who irradiated less than 30 Gy were excluded, 10 patients were eligible for this study. Median age was 51 years. Initial FIGO stage was 1 stage IBI, 2 stage IIA, 7 stage IIB. For initial treatment, 7 patients received radical radiotherapy and 3 received postoperative radiotherapy. The paraaortic field encompassed the gross recurrent disease with superior margin at T12, and inferior margin was between L5 and S1 with gap for previously pelvic radiation field. The radiation field was initially anterior and posterior opposed field followed by both lateral field. The daily dose was 1.2 Gy, twice daily fractions, and total radiotherapy dose was between 50.4 and 60 Gy(median, 58.8 Gy). Concurrent chemotherapy was done with paclitaxel as a radiosensitizer. Dose range was from 20 mg/m$^{3}$ to 30 mg/m$^{3}$ (median, 25 mg/m$^{3}$), and cycle of chemotherapy was from 3 to 6 (median, 4.5 cycle). Follow-up period ranged from 3 to 21 months. Results : Interval between initial diagnosis and paraaortic node recurrence was range from 2 to 63 months (median, 8 months). The 1 year overall survival rate and median survival were 75$\%$ and 9.5 months, respectively. The 1 year disease free survival rate and median disease free survival were 30$\%$ and 7 months, respectively. At 1 month after treatment, 4 (40$\%$) achieved a complete response and 6 (60$\%$) experienced a partial response and all patients showed response above the partial response. There was distant metastasis in 6 patients and pelvic node recurrence In 2 patients after paraaortic node irradiation. There was 2 patients with grade 3 to 4 leukopenla and 8 patients with grade 1 to 2 nausea/ vomiting which was usually tolerable with antlemetic drug. There was no chronic complication in abdomen and pelvis during follow up period. Conclusion : hypefractionated radiation therapy combined with paclitaxel chemotherapy diosensitizer showed high response rate and few complication rate in paraaortic node recurrence in cervix cancer Therefore, present results suggest that hypefractionated radiation therapy combined with paclitaxel chemotherapy can be used as optimal treatment modality in this patients.

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Development of Dual Reporter System of Mutant Dopamine 2 Receptor ($D_2R$) and Sodium Iodide Symporter (NIS) Transgenes (변이 도파민 2 수용체와 나트륨 옥소 공동 수송체 이입유전자의 이중 리포터시스템 개발)

  • Hwang, Do-Won;Lee, Dong-Soo;Kang, Joo-Hyun;Chang, Young-Soo;Kim, Yun-Hui;Jeong, Jae-Min;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.4
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    • pp.294-299
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    • 2004
  • Purpose: Both human NIS and mutant $D_2R$ transgenes are proposed as reporting system in transplanted cell tracking. Using hepatoma cell lines, we constructed a dual reporter system containing human sodium-iodide symporter (hNIS) and dopamine 2 receptor ($D_2R$) and compared its characteristics. Materials and Methods: The recombinant plasmid ($pIRES-hNIS/D_2R$) was constructed with IRES (internal ribosome entry site) under control of the CMV promoter $pIRES-hNIS/D_2R$ was transfected to human hepatoma SK-Hep1 cell line with lipofectamine. HEP-ND ($SK-Hep1-hNIS/D_2R$) cells stably expressing hNIS and $D_2R$ was established by selection with G418 for two weeks. RT-PCR was performed to investigate the expression of both hNIS and $D_2R$ genes. The expressions of hNIS and $D_2R$ were measured by $^{125}I$ uptake assays and receptor binding assays. Specific binding of $D_2R$ to $[^3H]spiperone$ was verified by Scatchard plot with (+) butaclamol as a specific inhibitor. $K_d\;and\;B_{max}$ values were estimated. The correlation between hNIS and $D_2R$ expression was compared by using each clone. Results: Similar quantities of hNIS and $D_2R$ genes were expressed on HEP-ND as RT-PCR assays. HEP-ND cells showed 30 to 40 fold higher radioiodine uptakes than those of parental SK-Hep1 cells. $^{125}I$ uptake in HEP-ND cells was completely inhibited by $KClO_4$, a NIS inhibitor Specific binding to HEP-ND cells was saturable and the $K_d\;and\;B_{max}$ values for HEP-ND cells were 2.92 nM, 745.25 fmol/mg protein and 2.91nM, 1323 fmole/mg protein in two clones, respectively. The radioiodine uptake by hNIS activity and $D_2R$ binding was highly correlated. Conclusion: We developed a dual positron and gamma imaging reporter system of hNIS and $D_2R$ in a stably transfected cell line. We expect that $D_2R$ and hNIS genes can complement mutually as a nuclear reporting system or that $D_2R$ can be used as reporter gene when hNIS gene were used as a treatment gene.

Effect of Dietary Streptococcus faecium on the Performances and the Changes of Intestinal Microflora of Broiler Chicks (Streptococcus faecium의 급여가 육계의 성장과 장내 세균총 변화에 미치는 영향)

  • Kim, K.S.;Chee, K.M.;Lee, S.J.;Cho, S.K.;Kim, S.S.;Lee, W.
    • Korean Journal of Poultry Science
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    • v.18 no.2
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    • pp.97-119
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    • 1991
  • Effect of Streptococcus faecium(SF) and an antibiotic, Colistin(Col), supplemented to diets singly or in combination, on the performances and changes of intestinal population of microflora of broiler chicks studied. A total of 252, day-old chicks(Arbor Acre) of mixed sex(M:F=1:1) were alloted into six groups. A diet with no Col and SF was referred as a control diet. The basal diets were added with two levels of SF, 0.04 and 0.08%, singly or in combination with Col 10ppm Another diet was prepared by adding only Col 10 ppm. Numbers of the microorganism in diets added with SF 0.04% and 0.08% were 7$\times$10$^{4}$ and 1.4$\times$10$^{5}$ /g diet respectively The diets consisting of corn and soybean meal as major ingredients were fed for a period of seven weeks . During the feeding trial, fresh excreta were sampled at the end of every week in a sterilized condition to count microbial changes from each dietary group. Microbial changes of large intestine were also measured from nine birds sacrificed at the end of the 4th and 7th weeks each time per dietary group. Excreta from all the groups were also collected quantitatively at the end of 3rd and 6th weeks to measure digestibility of the diets, At the end of 7th week, nine birds from each group were also sacrificed to measure weight changes of gastrointestinal tracts . Average body weight gains of broilers fed the diets added with SF 0.08% (2.37kg) or SF 0. 08%+col 10ppm(2.34kg) were significantly larger than that of the control(2.18kg). The weight gains of the other groups were not statistically different from that of the control Feed/gain ratios of the supplemental groups were better than that of control (P<0.05) except that of birds fed the diet added only with SF 0.04%. Digestibilities of nutrients such as dry matter, crude protein, crude fat and total carbohydrates were not altered by the consumption of the diets added with SF and/or Col throughout the whole feeding period. As expected, the numbers of Streptococci in the excreta from birds fed diets added with SF increased significantly with a statistical difference between groups with SF 0.04% and SF 0.08% most of the time. However. addition of Colistin to the diets supplemented with SF did not give any effects on the number of the microorganism. Numbers of coliforms in the excreta were apparently reduced by feeding the diets added with SF and/or Col(P<0.05). There were, however, no additive effects observed between the two feed additives in this regard when supplementing Col to the SF diets. Distributions of intestinal microflora exhibited exactly the same pattern as those of the excreta. Length of small intestine of the birds fed diets added with SF 0.08% with or without Col 10 ppm became significantly longer with a range of about 10% than those of the birds fed diets without SF. However, the empty weight of the small inestine of the former group was lighter than that of control These changes resulted in a significant reduction in weight/unit length of the intestine of the birds fed diets supplemented with Col and SF singly or in combination. In overall conclusion, diet added with SF 0.08% appeared most effective in improving broiler performances. Colistin added at a level of 10ppm was not beneficial at all in itself or in combination with SF in terms of broiler performances or changes of intestinal microflora population. The efficacy of SF and Col could be attributed to the changes of wall thickness of the small intestine.

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Preoperative Concurrent Radio-chemotherapy for Rectal Cancer: Report of Early Results (직장암에 대한 수술 전 동시병용 방사선-항암 화학요법: 초기 치료결과 보고)

  • Shin, Seong-Soo;Ahn, Yong-Chan;Chun, Ho-Kyung;Lee, Woo-Yong;Kang, Won-Ki;Park, Young-Suk;Park, Joon-Oh;Song, Sang-Yong;Lim-Do-Hoon;Park, Won;Lee, Jung, Eun;Kang, Min-Kyu;Park, Yung-Je
    • Radiation Oncology Journal
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    • v.21 no.2
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    • pp.125-134
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    • 2003
  • Purpose: To report the early results of preopeartive concurrent radio-chemotherapy (CRCT) for treating rectal cancer. Materials and Methods: From June 1999 to April 2002, 40 rectal cancer patients who either had lesions with a questionable resectability or were candidates for sphincter-sacrificing surgery received preoperative CRCT. Thirty-seven patients completed the planned CRCT course. 45 Gy by 1.8 Gy daily fraction over 5 weeks was delivered to the whole pelvis in the prone position. The chemotherapy regimens were oral UFT plus oral leucovorin (LV) in 12 patients, intravenous bolus 5-FU plus LV in 10 patients, and intravenous 5-FU alone in 15 patients (bolus infusion in 10, continuous infusion in 5). Surgery was planned in 4$\~$6 weeks of the completion of the preoperative CRCT course, and surgery was attempted in 35 patients. Results: The compliance to the current preoperative CRCT protocol was excellent, where 92.5$\%$ (37/40) completed the planned treatment. Among 35 patients, in whom surgery was attempted after excluding two patients with new metastatic lesions in the liver and the lung, sphincter-preservation was achieved in 22 patients (62.9$\%$), while resection was abandoned during laparotomy in two patients (5.7$\%$). Gross complete resection was peformed in 30 patients, gross incomplete resection was peformed in one patient, and no detailed information on the extent of surgery was available in two patients. Based on the surgical and pathological findings, the down-staging rate was 45.5$\%$ (15/33), and the complete resection rate with the negative resection margin 78.8$\%$ (26/33). During the CRCT course, grade 3 $\~$4 neutropenia developed in four patients (10.8$\%$). Local recurrence after surgical resection developed in 12.1$\%$ (4/33), and distant metastases after the preoperative CRCT start developed in 21.6$\%$ (8/37). The overall 3-years survival rate was 87$\%$. Conclusion: Preoperative CRCT in locally advanced rectal cancer is well tolerated and can lead to high resection rate, down-staging rate, sphincter preservation rate, however, longer term follow-up will be necessary to confirm these results.

The Role of Intraluminal Brachytherapy in Management of Esophageal Cancer (식도암 치료에 있어 관내근접치료의 역할)

  • Lee Chang Geol;Suh Chang Ok;Kim Gwi Eon;Chu Sung Sil;Chung Eun Ji;Kim Woo Cheol
    • Radiation Oncology Journal
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    • v.13 no.4
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    • pp.331-338
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    • 1995
  • Purpose : To evaluate our clinical experience with the combination of teletherapy and intraluminal brachytherapy in patients with unresectable or inoperable esophageal cancers. Materials and Methods : From Nov 1989 to Mar 1993, twenty patients with esophageal cancer were treated with radical radiotherapy and intraluminal brachytherapy at Yonsei Cancer Center. All patients had squamous histolgy and stage distribution was as follows: stage II, 4($20{\%}$)patients; III, 15 ($75{\%}$)patients; IV, 1($5{\%}$)patients. A dose of S-12Gy/1-3weeks with intraluminal brachytherapy (3-5Gy/fraction) to 5mm from the outside of the esophageal tube using high dose rate Iridium-192 remotely afterloading brachytherapy machine was given 2 weeks after a total dose of 59-64Gy with external radiotherapy. Induction chemotherapy using cisplatin and 5-FU was performed in 13 patients with median 3 cycles(1-6 cycles), Response rate, local control rate, survival and complications were analysed retrospectively. Results : Two-year overall survival rate and median survival were $15.8{\%}$ and 13.5 months. Response rates were as follows complete remission(CR) 5($25{\%}$): partial remission a(PRa) 7($35{\%}$): partial remission b(PRb) 7($35{\%}$), no response(NR) 1($5{\%}$). Patterns of failure were as follows; local failure 13($65{\%}$), local and distant failure 3($15{\%}$), distant failure 0($0{\%}$). Ultimate local control rate was $20{\%}$. Treatment related complications included esophageal ulcer in two patients and esophageal stricture in one. Conclusion : Though poor local conrol rate, median survival was improved as compared with previous results of radiation therapy alone(8months) and chemoradiation combined treatment(11 months) in Yonsei Cancer Center High-dose-rate intraluminal brachytherapy following external irradiation is an effective treatment modality with acceptable toxicity in esophageal cancer.

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Effects of Blended Essential Oil(CRINA®) Supplementation on the Performance, Nutrient Digestibility, Small Intestinal Microflora and Fatty Acid Composition of Meat in Broiler Chickens (사료중 Blended Essential Oil(CRINA®) 첨가가 육계의 생산성과 영양소 이용률, 소장 내 미생물 균총 및 계육내 지방산 조성에 미치는 영향)

  • Suk, J.C.;Lim , H.S.;Paik, I.K.
    • Journal of Animal Science and Technology
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    • v.45 no.5
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    • pp.777-786
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    • 2003
  • An experiment was conducted to investigate the effects of supplementary Blended essential oil(CRINA$^{\circledR}$) on the performance, nutrient availability, fatty acid composition of leg muscle, small intestinal microflora and blood parameters in broiler chickens. One thousand unsexed day-old broiler chickens were assigned to five treatments : control(T1), 5ppm avilamycin(starter diet) & 5ppm flavomycin(grower diet) T2, 5ppm avilamycin(starter diet) & 50ppm CRINA$^{\circledR}$(grower diet) T3, 50ppm CRINA$^{\circledR}$(starter & grower diet) T4, 50ppm CRINA$^{\circledR}$+ 500ppm lactic acid$^{\circledR}$ (starter & grower diet) T5. Each treatment had four replications of 50 birds each. Growth performance was significantly improved by dietary supplements(T2-T5). There were no significant differences among treatment T2, T3, T4 and T5. Feed intake was not significantly different among treatments. Dietary supplementation of CRINA$^{\circledR}$(T3, T4, T5) resulted in significant(p〈0.05) improvement in feed/gain(F/G) during finishing period (4-5weeks). The birds fed CRINA$^{\circledR}$ supplemented diet(T4) showed significantly(p〈0.05) higher availability of crude fat, methionine and methionine + cystine than those fed antibiotics supplemented diet(T2). Mortality was not significantly affected by treatments. The colony forming unit(CFU) of E.coli in small intestinal content was significantly lower in antibiotics & CRINA$^{\circledR}$(T3) compared to CRINA$^{\circledR}$ treatment(T4)(P〈0.05). CFU of Cl. perfringens was low in CRINA$^{\circledR}$(T4) but not different significantly with other treatments. Serum triglyceride level of birds fed CRINA$^{\circledR}$ + lactic acid diet(T5) was significantly lower(p〈0.05) than those fed antibiotics supplemented diet(T2). Cholesterol level of the birds fed antibiotics(T2) or CRINA$^{\circledR}$ + lactic acid supplemented diet(T5) was significantly higher(p〈0.05) than other treatments. HDL level of birds fed control diet was significantly lower(p〈0.05) than that of others. The levels of serum IgG were not significantly different among treatments. Major fatty acids composition of leg muscle fat was significantly influenced by treatments. Control group showed significantly higher palmitic acid(C$_{16:0}$) and steraric acid(C$_{18:0}$) content than other treatments(p〈0.05). Content of oleic acid(C$_{18:1}$), however, was significantly lower in the control than others treatments. Content of linolenic acid(C$_{18:3}$) was significantly higher in CRINA$^{\circledR}$+ lactic acid(T5) than antibiotics & CRINA$^{\circledR}$(T3) treatments. Total saturated fatty acids content was higher and total unsaturated fatty acids were lower in the leg muscle fat of the control than that of other treatments. It is concluded that CRINA$^{\circledR}$ supplementation improved growth rate and F/G ratio in broilers. The combination of CRINA$^{\circledR}$ with either antibiotics or lactic acid did not show any additive or synergistic effects in broiler chickens .

Characteristics of Spatio-temporal Variation of the Water Quality in the Lower Keum River (금강 하류역에서 수질의 시공간적 변화특성)

  • YANG Han-Soeb;KIM Seong-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.3
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    • pp.225-237
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    • 1990
  • Various chemical constituents were measured from April to August 1988 at the down-ward 20 stations of Keum River, which is located in the Midwest of Korea, to understand the characteristics of water quality with respect to spatio-temporal variations of each constituent. The 24-hrs continuous measurements with 2-hrs interval were made simultaneously at station 2 near the estuary weir and station 9(Ganggyeong) of 35 km upstream from the weir in April. By the results observed for one day in April at station 2, salinity has a range of $7.88\~22.14\%_{\circ}$ and its temporal variability is identical to the pattern of tidal cycle in the neigh-bouring Kunsan Harbor. However, turbidity shows relatively high values only at an interval of 4~5 hours after the lowest salinity time, though hourly fluctuation of pH is very small. Silicate and dissolved inorganic nitrogen have inversively linear correlationships with salinity, implying the concentration of the two nutrients strongly regulated by estuarine mixing of sea and river waters. In contrast, phosphate sustains roughly a constant level over a wide salinity range and distinctly lower values than those corresponding to nitrate in the oceans. Such distributions of phosphate have been observed in some estuaries, and interpreted as driven by removal of dissolved phosphate into bottom sediments and the bufforing of phosphate by particulate matter. COD values at station 2 are relatively high in day-time(particularly afternoon) and in high-salinity periods. At station 9, saltwater intrusion was never found but water level changed to the extent of 2.5 m for one day. Although each parameter at this station exhibits very slight variations in their abundance for 24 hours compared with station 2, the contents of COD, silicate and ammonia are significantly higher than at station 2. Concentration of suspended matter is relatively high in the brackish water region up to $\~20$ km above the river mouth, probably due to strong tidal stirring of the bottom de-posits. Also, relatively high pH, COD and $O_2$ saturation at the upward stations of $40\~50$ km from the weir are presumably attributable to active photosynthesis of plants in the region. In general, COD and nutrients except phosphate are higher values at the upper stations than in the estuary zone, and show the highest abundances in July nearly at all stations. Finally, in the estuarine region tidal mixing of sea-river waters seems to be an important factor controlling the distributions of turbidity, COD, silicate and nitrate as well as salinity. However, water quality in the upward fresh-water zone is remarkably variable according to months or seasons.

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Environmental Pollution in Korea and Its Control (우리나라의 환경오염 현황과 그 대책)

  • 윤명조
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1972.03a
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    • pp.5-6
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    • 1972
  • Noise and air pollution, which accompany the development of industry and the increase of population, contribute to the deterioration of urban environment. The air pollution level of Seoul has gradually increased and the city residents are suffering from a high pollution of noise. If no measures were taken against pollution, the amount of emission of pollutant into air would be 36.7 thousand tons per year per square kilometer in 1975, three times more than that of 1970, and it would be the same level as that of United States in 1968. The main sources of air pollution in Seoul are the exhaust has from vehicles and the combustion of bunker-C oil for heating purpose. Thus, it is urgent that an exhaust gas cleaner should be instaled to every car and the fuel substituted by less sulfur-contained-oil to prevent the pollution. Transportation noise (vehicular noise and train noise) is the main component of urban noise problem. The average noise level in downtown area is about 75㏈ with maximum of 85㏈ and the vehicular homing was checked 100㏈ up and down. Therefore, the reduction of the number of bus-stop the strict regulation of homing in downtown area and a better maintenance of car should be an effective measures against noise pollution in urban areas. Within the distance of 200 metres from railroad, the train noise exceeds the limit specified by the pollution control law in Korea. Especially, the level of noise and steam-whistle of train as measured by the ISO evaluation can adversely affect the community activities of residents. To prevent environmental destruction, many developed countries have taken more positive action against worsening pollution and such an action is now urgently required in this country.

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