• Title/Summary/Keyword: 규석

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Anti-metastastic Effects of ingredients of Fuzhengfangaitang (부정방암탕(扶正防癌湯) 구성(構成) 약물(藥物)의 암전이(癌轉移) 억제(抑制)에 대한 연구(硏究))

  • Park, Joon-Hyuck;Yu, Young-Beob;Shim, Bum-Sang;Choi, Seung-Hoon;Ahn, Koo-Seok
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.7 no.1
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    • pp.39-60
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    • 2001
  • Fuzhengfangaitang is a prescript for inhibiting recurrence and metastasis of cancer. We had examined the anti-metatstastic effect of Fuzhengfangaitang. Furthermore, we performed the following experiments with ingredients of Fuzhengfangaitang. The purpose of this thesis is to study what ingredients of Fuzhengfangaitang have more valuable anti-cancer effects. And the results are listed below: 1. Cell Viability assay At the dose of 400$\mu$g/ml, most ingredients of Fuzhengfangaitang depressed viability of ECV-304. And especially, Scutellaria barbata D. DON$50{\mu}g/ml$ : 53.118%, $100{\mu}g/ml$: 49.092%, $200{\mu}g/ml$ : 43.765%, $400{\mu}g/ml$ : 12.747%), Polygonum bistorta L.($50{\mu}g/ml$ : 45.554%, $100{\mu}g/ml$ : 45.554%, $200{\mu}g/ml$ : 0.0%, $400{\mu}g/ml$ : 0.0%) and Psoralea corylifolia L.($50{\mu}g/ml$ : 86.591%, $100{\mu}g/ml$ : 81.307%, $200{\mu}g/ml$ : 24.801%, $400{\mu}g/ml$ : 3.111%) highly depressed cell viability more than the other ingredients. (${\alpha}$<0.05) 2. Cell Proliferation assay Proliferation assay with ingredients of Fuzhengfangaitang on ECV-304 showed that Crataegus pinnatifuda BGE ($50{\mu}g/ml$: 63.276%, $100{\mu}g/ml$ : 64.092%, $200{\mu}g/ml$ : 68.966% $400{\mu}g/ml$ : 38.517%, ED50=$296.974{\mu}g/ml$), Polygonum bistorta L.($50{\mu}g/ml$ : 83.981%, $100{\mu}g/ml$ : 86.997%, $200{\mu}g/ml$ : 58.780%, $400{\mu}g/ml$ : 26.408%), ED50=$266.725{\mu}g/ml$) and Psoralea corylifolia L.($50{\mu}g/ml$ : 103.037%, $100{\mu}g/ml$ : 82.529%, $200{\mu}g/ml$ : 2.829%, $400{\mu}g/ml$ : 0.998%), ED50=$177.369{\mu}g/ml$) depressed cell proliferation more than the other ingredients. 3. Tube Formation assay Compared with the control group, most ingredients of Fuzhengfangaitang did not remarkably inhibited the Tube Formation assay of ECV-304 at the dose of $100{\mu}g/ml$. But, Polygonum bistorta L. highly inhibited the tube formation of ECV -304 at the lower dose of $50{\mu}g/ml$. 4. Rat Aortic Ring assay In comparison with the control group, Scutellaria barbata D. DON., root of Polygonum bistorta L. and Psoralea corylifolia L. restricted the angiogenesis of the rat aortic ring at the dose of $100{\mu}g/ml$. And the other ingredients of Fuzhengfangaitang did not restricted the angiogenesis of the rat aortic ring at that dose. Especially, Polygonum bistorta L. highly inhibited the angiogenesis of the rat aortic ring at the lower dose of $50{\mu}g/ml$. From our research, the anti-angiogenic effects of the ingredients of Fuzhengfangaitang was proven. Moreover, it will be helpful for designing more effective prescription for anti angiogenesis.

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Effect of Whalakyuoleyng-dan plus Yinsamyangwui-tang on Anti-angionesis (활락효영단합인삼양위탕(活絡效靈丹合人蔘養胃湯)이 혈관신생(血管新生) 억제(抑制)에 미치는 영향(影響))

  • Ko, Ki-Wan;Park, Joon-Hyuk;Kang, Hee;Kim, Sung-Hoon;Yu, Young-Beob;Shim, Bum-Sang;Choi, Seung-Hoon;Ahn, Koo-Seok
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.7 no.1
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    • pp.77-97
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    • 2001
  • Anti-angiogenesis is one of therapies which have been high-lightened on the research of cancer treatment. Anti-angiogenesis means that new blood vessels are created from a existing capillary tube and it is a important process on metastasis and permeation when cancer is created or formed. Since angiogenesis have been under research, a complete recovery oriented treatment against cancer have been suggested blocking metastasis, delaying the growth of cancer cell, and blocking the supply of oxygen and nutritive substance through the web of blood vessels. Until now, there are several anti-angiogenesis, which have been known to the public, such as thalidomide, angiostatin, endostatin, 2-methoxyestradiol, TNP-470, and marimastat, etc. Additionally, 17 clinical testing projects about anti-angiogenesis are on the process in NCI(National Cancer Institute). Especially, TNP-470 showed effectiveness against cancer on clinical testing after finishing animal testing. Based on existing researches showing that Yinsamyangwui-tang is effective to strengthening body resistance and Whallakhyolenyng-dan effects cells on the inside of blood vessel because Whallakhyolenyng- dan restrains cell adhesion during the restraining period of a blood vessel, I tried to research the effect of Whalakhyolenyng-dan plus Yinsamyangwui-tang on angiogenesis. I made a conclusion putting into operation through using SK-Hep-1 (KCLB 30052), A549(KCLB 10185), AGS(KCLB 21739), and BCE(Bovine Capillary Endothelial Cell). Followings are the results of my experimental research: 1. According to the researching results of anti-cancer activation against cancer cell, Whallkhyoleyng dan plus Yinsamyangwui-tang decreased the number of cancer cells -- While injecting $600{\mu}g/ml$, injected groups decreased 3.1% more comparing with the contrastive group of SK-Hep-1, 49.7% more comparing with the contrastive group of A549, and 31.0% more comparing with the contrastive group of AGS. 2. According to the researching results of DNA composition effect between BCE and cancer cell, Whallakhyoleyng-dan plus Yinsamyangwui-tang reduced the rate of SK-Hep-1 synthesis inhibition by 59.1% at $600{\mu}g/ml$ intensity comparing with contrastive group; for A549, 72.6%; for AGS, 6.1%, for BCE, 28.9%. 3. According to the researching results about the effect of BCE cell to angiogenesis, angiogenesis was restrained at $400{\mu}g/ml$ intensity during 18 hours observation. 4. In the case of aortic ring assay, the half level of angiogenesis was reduced comparing with the contrastive group while injecting with $400{\mu}g/ml$ intensity; with $800{\mu}g/ml$, under 10% comparing with contrastive group; and with $1600{\mu}g/ml$, complete restrain. According to the above results, Whallakhyoleyng-dan plus Yinsamyangwui-tang was proved to have an anti-angiogenetic effects.

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Clinical Investigation about the Result of Surgically Treated Myasthenia Gravis (중증 근무력증의 수술적 치료결과에 대한 임상적 고찰)

  • 김대현;황은구;조규석;김범식;박주철
    • Journal of Chest Surgery
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    • v.36 no.1
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    • pp.15-20
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    • 2003
  • Myasthenia gravis is a rare autoimmune disease involving acetylcholine receptor and its autoantibody on neuromuscular junction. The methods of treatment are medical treatment and surgical thymectomy. In this paper we analyzed the result of thymectomy and the factors affecting the postoperative symptom improvement. Material and method : This study obtained medical records of 37 patients who received the thymectomy for myasthenia gravis from March 1986 to December 1998. Result Out of 37 cases, 21 cases(57%) showed improvement, of which 8 cases (50%) in the group of thymoma(n=16), and 13 cases (62%) in the group of thymic hyperplasia(n=21) showed the improvement of symptoms. Postoperative complications were respiratory insufficiency due to aggravation of symptoms after operation, including tracheal intubation for ventilator support in 9 cases, pneumonia in 3 cases, pneumothorax in 2 cases and left vocal cord palsy in 1 case. There was one postoperative mortality. The relation between postoperative improvement and sex(P=0.3222), age(P=0.7642), thymic pathologic variants,(P=0.4335) and classification of thymoma(P=0.20) showed no statistically significant correlation. However, the lower grade of preoperative symptoms can predict the lower grade of postoperative symptoms significantly(P=0.0032). Follow up study to 36 postoperative survivors was performed in October 2002 based on the out-patient records and call with patients. Out of 36 cases, 33 cases(91.7%) could be investigated and 3 cases could not. Mean follow up period was 83.2 months. Out of 33 cases, 25 cases(75.8%) showed symptomatic improvement, of which 8 cases(53.3%) in the group of thymoma(n=15) and 17 cases(94.4%) in the group of thymic hyperplasia(n=18) showed the improvement of$\boxUl$ symptoms. Conclusion : In myasthenia gravis, thymectomy showed the good improvement, and more important factor affecting the improvement of symptoms was the grdae of preoperative symptoms. Also midterm and long term follow up results showed good symptomatic improvement.

Effect of Marbling Score on Carcass Grade Factors, Physico-chemical and Sensory Traits of M. Longissimus Dorsi in Hanwoo (근내지방도가 한우 도체등급 요인, 이화학적 특성 및 관능적 특성에 미치는 영향)

  • Lee, Jong-Moon;Choe, Ju-Hui;Jin, Hyune-Ju;Kim, Tae-Il;Park, Beom-Young;Hwang, Do-Yon;Koh, Kyung-Chul;Kim, Cheon-Jei;Hwang, Kyu-Seok
    • Food Science of Animal Resources
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    • v.32 no.5
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    • pp.659-668
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    • 2012
  • The objective of this research was to investigate the effect of marbling scores on carcass grade factors, physico-chemical and sensory traits of Hanwoo. Data used in this study were collected from 73,316 carcasses obtained at the Nonghyup Seoul slaughterhouse in 2009 and 271 cuts of M. longissimusdorsi were analyzed to estimate beef qualities. As the marbling scores increased, backfat thickness was linearly increased (p<0.05) in cows (9.51 mm-14.69 mm) and steers (8.71 mm-14.23 mm). As the marbling scores increased, maturity of cows was increased and meat color, texture and quality grade improved for all genders. With increase of the marbling scores, crude fat contents (3.07%-26.70%), water holding capacity (52.09%-58.66%), $L^*$ value (34.08-41.97) were significantly increased (p<0.05) and Warner-Bratzler shear force was linearly decreased (p<0.05) from 8.58 kg to 2.60 kg. The increase of crude fat contents had the similar interval with the increase of marbling scores from 1 to 6 but it is sharply increased from marbling score 7. There was no difference observed on $pH_{24}$ (5.50-5.66), protein contents (19.57%-21.15%) among the marbling scores. Marbling score was significantly correlated with live weight (r=0.29) in cows, loineye area (r=0.35) in steer, and overall acceptability of panel scores (r=0.67) (p<0.01).

Metamorphism of the Buncheon and Hongjeas Granitic Gneisses (분천과 홍제사 화강암질 편마암체의 변성작용)

  • 김형수;이종혁
    • The Journal of the Petrological Society of Korea
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    • v.4 no.1
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    • pp.61-87
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    • 1995
  • On the basis of lithology, the Precambrian Hongjesa Granitic Gneiss can be locally zoned into granoblastic granitic gneiss, porphyroblastic granitic gneiss, migmatitic gneiss from its center to the marginal part. There are no distinct differences in mineral assemblages by lithologic zoning, but it partly shows the change of mineral assemblage in the adjacent with migmatitic gneiss, thus mineral assemblage can be subdivided into Zone I and Zone II. In terms of mineral compositions, the characteristics of Zone I are coexisting K-feldspar+muscovite+sillimanite. The characteristics of Zone II are (1) breakdown of muscovite, (2) coexisting garnetScordierite, (3) coexisting garnet+cordierite + orthoamphibole. The Buncheon Granitic Gneiss is mainly composed of augen gneiss. In the adjacent area with Honjesa Granitic Gneisses, Buncheon Granitic Gneiss has the mineral assemblage of sillimanite+biotite+K-feldspar+(kyanite). Kyanite occurs as relict grains in the Buncheon and Hongjesa Granitic Gneissess. Kyanite shows anhedral to subhedral form and coexists with sillimanite in only one of these samples. Garnet from a migmatitic gneiss (Zone 11) has relatively high $X_{Fe}$ value in core and rim. Garnet from a porphyroblastic granitic gneiss(Zone I) has relatively homogemeous core but compositionally-zoned rim. Biotites show various colour from greenish-brown, brown to reddish brown at maximum adsorption. Also, the Ti, and Mg content in biotites increases from Zone I to Zone II. The plagioclases shows the chemical composition of $Ab_{84}An_{16}$ -$Ab_{70}An_{30}$ (oligoclase) in Zone I and $Ab_{70}An_{30}$ -$Ab_{50}An_{50}$(andesine) in Zone 11. These variations indicate that the gneisses in the study area experienced a upperamphibolite facies. The presence of kyanite as relict grains indicates that the metamorphic rocks in this area exprienced a high-temperature/medium-pressure type metamorphism, followed by high-temperaturellow-pressure metamorphism. Metamorphic P-T conditions for each gneiss estimated from various geothermobarometers and phase equilibria are 698-$729^{\circ}C$/6.3-11.3 kbar in augen gneiss, 621-$667^{\circ}C$/1.0-5.4 kbar in migmatitic gneiss, and 602-$624^{\circ}C$/1.9-3.4 kbar in porphyroblastic granitic gneiss. These data suggest that the study area was subjected to a clockwise P-T path with isothermal decompression (dP/dT=about 60 bar/$^{\circ}C$).

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Surgical Treatment for Carotid Artery Stenosis (경동맥 협착증의 수술적 치료)

  • Kim, Dae-Hyun;Yi, In-Ho;Youn, Hyo-Chul;Kim, Bum-Shik;Cho, Kyu-Seok;Kim, Soo-Cheol;Hwang, Eun-Gu;Park, Joo-Chul
    • Journal of Chest Surgery
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    • v.39 no.11 s.268
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    • pp.815-821
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    • 2006
  • Background: Carotid endarterectomy is an effective treatment modality in patients with severe carotid artery stenosis, but it may result in serious postoperative complications, We analyzed the results of the carotid endarterectomy performed in our institution to reduce the complications related to the card endarterectomy. Material and Method: We analyzed retrospectively the medical records of 74 patients(76 cases) who underwent carotid endarterectomy for carotid artery stenosis by a single surgeon from February 1996 to July 2004. Result: There were 64 men and 10 women. The mean age of the patients was 63.6 years old. Carotid endarterectomy only was performed in 63 cases, carotid endarterectomy with patch angioplasty in 8 cases, and carotid endarterectomy with segmental resection of internal carotid artery and end to end anastomosis in 5 cases. Intra-arterial shunt was used in 29 cases. The mean back pressures of internal carotid arteries checked after clamping common carotid arteries and external carotid arteries were $23.48{\pm}10.04$ mmHg in 25 cases with changes in electroencephalography(group A) and $47.16{\pm}16.04$ mmHg in 51 cases without changes in electroencephalography(group B). There was no statistical difference in the mean back pressure of internal carotid arteries between two groups(p=0.095), but the back pressures of internal carotid arteries of all patients with changes in electroencephalography were under 40 mmHg. When there was no ischemic change of electroencephalography after clamping common carotid artery and external carotid artery, we did not make use of intra-arterial shunt regardless of the back pressure of internal carotid artery. Operative complications were transient hypoglossal nerve palsy in four cases, cerebral hemorrhage occurred at previous cerebral infarction site in two cases, mild cerebral infarction in one case, hematoma due to anastomosis site bleeding in one case, and upper airway obstruction due to laryngeal edema probably caused by excessive retraction during operation in two cases. One patient expired due to cerebral hemorrhage occurring at previous cerebral infarction site. Conclusion: Carotid endarterectomy is a safe operative procedure showing low operative mortality. We suggest that intra-arterial shunt usage should be decided according to the ischemic change of electroercephalography regardless of the back pressure of internal carotid artery. Excessive retraction during operation should be avoided to prevent upper alway obstruction due to laryngeal edema and if upper airway obstruction is suspected, prompt management is essential.

A Study on the Effects of Temperature Rise of Irrigation Water Passed Through the Warm Water Pool. (온수지에 의한 관개용수의 수온상승 효과에 관한 연구)

  • 연규석;최예환
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.19 no.1
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    • pp.4323-4337
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    • 1977
  • The study was to estimate the effect of the rise of water temperature in the warm water pool and to make contribution to the establishment of reducing to a damage of cool water as well as to the planning for warm water pool. This observation was performed in Wudu warm water pool located at Wudu-Dong of Chuncheon for two years from 1975 to 1976. The results were showed as follows; 1. The daily variation of water temperature was the least for inset (No.1; 0.6$^{\circ}C$) the second for middle overflow (No2: 3$^{\circ}C$, No.3; 2.3$^{\circ}C$) and another for outflet (No.4; 3.6$^{\circ}C$, No.5; 3.8$^{\circ}C$) And the highest reaching time of water temperature in each block was later about 1 hour than the time at which air temperature happend in the daytime. So, the variation of water temperature was sensitive to the variation of air temperature 2. The monthly variation of water temperature at each measuring point was plotted to be increased with increase in air temperature till August (Mean monthly rising degree; No.1; 1.15$^{\circ}C$, No.2; 1.7$^{\circ}C$, No.3; 1.73$^{\circ}C$, No.4; 2.08$^{\circ}C$, No.5; 2.0$^{\circ}C$), and expressed gradually descended influence upon water temperature after August. 3. The mean temperature of inflow folwed in warm Water pool was 7.5∼12.5$^{\circ}C$, and outflow temperature was described as 13.4∼22.5$^{\circ}C$ to be climbed. And So, the rising interval of water temperature was shown as 6.7∼10.4$^{\circ}C$. 4. The correlation between the rising of water temperature and the weather condition was found out highly significant. As the result, their correlation coefficents of water temperature depending on mean air temperature, ground temperature, wind velocity and relative humidity were to be 0.93, 0.90, - 0.83 and 0.71 respectively. But there was no confrimation of the correlation on the clouds, sunlight time, volume of evaporation, and heat capacity of horizontal place. 5. The water temperature of balance during the period of rice growing in Chuncheon district was shown as table 10, and the mean of whole period was calculated as about 23.7$^{\circ}C$. 6. The observed value of the outflow temperature passed through the warm water pool was higher than that of computed, the mean difference between two value was marked as 1.15$^{\circ}C$ for blockl, 1.18$^{\circ}C$ for block2, and 0.47$^{\circ}C$ for block3, respectivly. Therefore, the ratio on the rising degree between the observed and computed were shown as 53%, 44%, and 18%, mean 38% through each block warm water pool (referring item $\circled9$ of table 11,12, and 13). Accordingly, formula (4) in order to fit for each block warm water pool was transfromed as follow; {{{{ { theta }_{w } - { theta }_{ 0} =[1-exp LEFT { { 1-(1+2 varphi )} over {cp } CDOT { A} over { q} RIGHT } ] TIMES ( { theta }_{w } - { theta }_{ 0}) TIMES C }}}} Here, correction coefficinent was computed 1.38, and being substituted 1.38 for C in preceding formula, the expected water temperature will be calculated to be able to irrigate the rice paddy. As the result, we can apply the coefficient in order to plan and to construct a new warm water pool.

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Effect of Backfat Thickness on the Carcass Grade Factors and Carcass Price in Hanwoo Cows and Steers (등지방 두께가 한우 암소와 거세우의 도체 등급 요인 및 도체가격에 미치는 영향)

  • Lee, Jong-Moon;Choe, Ju-Hui;Park, Hyun-Kyung;Kim, Yuen-Ho;Park, Beom-Young;Kim, Kwan-Tae;Koh, Kyung-Chul;Seo, Sang-Chul;Hwang, Kyu-Seok
    • Food Science of Animal Resources
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    • v.31 no.2
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    • pp.280-289
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    • 2011
  • Analyses were conducted to estimate the effect of backfat thickness (BFT) on carcass grade factors and carcass price in Hanwoo cows and steers. Data on grade factors and prices were collected from 69,159 Hanwoo carcasses (n = 13,376 cows, n = 55,783 steers) abtained at the Nonghyup Seoul slaughter house in 2009. Carcass BFTs were divided into nine categories from ${\leq}$ 3 mm to ${\qeq}$ 25 mm. The average BFTs were 11.93 mm in cows and 12.57 mm in steers. An increase in the BFT resulted in an increase in carcass weight, loin-eye area, skeletal maturity, fat color, but decreases in the yield index and yield grade (from grade A to C) in cows and steers. Carcass unit price (Won/kg) improved if the carcass was sold with a BFT of 13-15 mm in cows and 10-12 mm in steers. Marbling score and quality grade increased significantly to 21 mm BFT but decreased from a BFT of 22 mm in cows and steers. BFT was significantly correlated with yield index (cow, r = $-0.97^{**}$; steer, r = $-0.96^{**}$), marbling score (cow, r = $0.20^{**}$; steer, r = $0.14^{**}$), and carcass price (cow, r = $0.03^{**}$; steer, r = $-0.11^{**}$). These results could be used as a fundamental dataset for further research to increase the productivity of Hanwoo carcasses.

Experimental Studies on the Properties of Epoxy Resin Mortars (에폭시 수지 모르터의 특성에 관한 실험적 연구)

  • 연규석;강신업
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.26 no.1
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    • pp.52-72
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    • 1984
  • This study was performed to obtain the basic data which can be applied to the use of epoxy resin mortars. The data was based on the properties of epoxy resin mortars depending upon various mixing ratios to compare those of cement mortar. The resin which was used at this experiment was Epi-Bis type epoxy resin which is extensively being used as concrete structures. In the case of epoxy resin mortar, mixing ratios of resin to fine aggregate were 1: 2, 1: 4, 1: 6, 1: 8, 1:10, 1 :12 and 1:14, but the ratio of cement to fine aggregate in cement mortar was 1 : 2.5. The results obtained are summarized as follows; 1.When the mixing ratio was 1: 6, the highest density was 2.01 g/cm$^3$, being lower than 2.13 g/cm$^3$ of that of cement mortar. 2.According to the water absorption and water permeability test, the watertightness was shown very high at the mixing ratios of 1: 2, 1: 4 and 1: 6. But then the mixing ratio was less than 1 : 6, the watertightness considerably decreased. By this result, it was regarded that optimum mixing ratio of epoxy resin mortar for watertight structures should be richer mixing ratio than 1: 6. 3.The hardening shrinkage was large as the mixing ratio became leaner, but the values were remarkably small as compared with cement mortar. And the influence of dryness and moisture was exerted little at richer mixing ratio than 1: 6, but its effect was obvious at the lean mixing ratio, 1: 8, 1:10,1:12 and 1:14. It was confirmed that the optimum mixing ratio for concrete structures which would be influenced by the repeated dryness and moisture should be rich mixing ratio higher than 1: 6. 4.The compressive, bending and splitting tensile strenghs were observed very high, even the value at the mixing ratio of 1:14 was higher than that of cement mortar. It showed that epoxy resin mortar especially was to have high strength in bending and splitting tensile strength. Also, the initial strength within 24 hours gave rise to high value. Thus it was clear that epoxy resin was rapid hardening material. The multiple regression equations of strength were computed depending on a function of mixing ratios and curing times. 5.The elastic moduli derived from the compressive stress-strain curve were slightly smaller than the value of cement mortar, and the toughness of epoxy resin mortar was larger than that of cement mortar. 6.The impact resistance was strong compared with cement mortar at all mixing ratios. Especially, bending impact strength by the square pillar specimens was higher than the impact resistance of flat specimens or cylinderic specimens. 7.The Brinell hardness was relatively larger than that of cement mortar, but it gradually decreased with the decline of mixing ratio, and Brinell hardness at mixing ratio of 1 :14 was much the same as cement mortar. 8.The abrasion rate of epoxy resin mortar at all mixing ratio, when Losangeles abation testing machine revolved 500 times, was very low. Even mixing ratio of 1 :14 was no more than 31.41%, which was less than critical abrasion rate 40% of coarse aggregate for cement concrete. Consequently, the abrasion rate of epoxy resin mortar was superior to cement mortar, and the relation between abrasion rate and Brinell hardness was highly significant as exponential curve. 9.The highest bond strength of epoxy resin mortar was 12.9 kg/cm$^2$ at the mixing ratio of 1:2. The failure of bonded flat steel specimens occurred on the part of epoxy resin mortar at the mixing ratio of 1: 2 and 1: 4, and that of bonded cement concrete specimens was fond on the part of combained concrete at the mixing ratio of 1 : 2 ,1: 4 and 1: 6. It was confirmed that the optimum mixing ratio for bonding of steel plate, and of cement concrete should be rich mixing ratio above 1 : 4 and 1 : 6 respectively. 10.The variations of color tone by heating began to take place at about 60˚C, and the ultimate change occurred at 120˚C. The compressive, bending and splitting tensile strengths increased with rising temperature up to 80˚ C, but these rapidly decreased when temperature was above 800 C. Accordingly, it was evident that the resistance temperature of epoxy resin mortar was about 80˚C which was generally considered lower than that of the other concrete materials. But it is likely that there is no problem in epoxy resin mortar when used for unnecessary materials of high temperature resistance. The multiple regression equations of strength were computed depending on a function of mixing ratios and heating temperatures. 11.The susceptibility to chemical attack of cement mortar was easily affected by inorganic and organic acid. and that of epoxy resin mortar with mixing ratio of 1: 4 was of great resistance. On the other hand, when mixing ratio was lower than 1 : 8 epoxy resin mortar had very poor resistance, especially being poor resistant to organicacid. Therefore, for the structures requiring chemical resistance optimum mixing of epoxy resin mortar should be rich mixing ratio higher than 1: 4.

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Changes of Haematological Constituents in the Nile tilapia, Oreochromis niloticus Exposed to HCB and PCBs (HCB와 PCBs에 노출된 나일틸라피아, Oreochromis niloticus의 혈액성분의 변화)

  • Cho Kyu Seok;Min Eun Young;Kang Ju Chan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.2
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    • pp.110-114
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    • 2002
  • The study was carried out to investigate the changes of haematological constituents induced by dietary exposure of Hexachlorobenzene (HCB) and Polychlorinated biphenyls (PCBs) in nile tilapia, Oreochhromis niloticus. The nile tilapia were fed pellet with 0.05, 0.25 and 0.50 mg/kg body weight/day of HCB and PCBs for 30 days, respectively. HCB ($\ge$ 0.25 mg/kg) induced a significantly decreased the red blood cell count at 30 days, and the hemoglobin concentration and hematocrit value were significantly decreased after 20 days to 0.50 mg/kg. The diminution of red blood cell count, hemoglobin concentration and hamatocrit value by PCBs was found after 20 days at $\ge$0.25 mg/kg. The concentrations of calcium decreased significantly at 30 days at $\ge$0,25 mg/kg of PCBs-diet. However, magnesium and inorganic phosphorus did not show any noticeable changes in the range of 0.05$\~$o.50 mg/kg of HCB and PCBs compared to control group during the experimental period, The low concentration of total protein was observed at the last day of experiment to 0.50 mg/kg of HCB-diet, while total protein initiated to increase from 20 days at the 0.25 mg/kg of PCBs-diet. The glucose was significantly increased after 20 days at $\ge$0,25 mg/kg of HCB and PCBs, A significant increment GOT and GPT activities was noticed after 20 days at 0.50 mg/kg of HCB and PCBs, These results indicate that hematological and serum biochemical changes in the nile tilapia by dietary exposure to HCB and PCBs are affected at more than 0,25 mg/kg after 20 days.