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Gadoteridol's Signal Change according to TR, TE Parameters in T1 Image (T1영상에서 TR, TE 매개변수에 따른 Gadoteridol의 신호강도 변화)

  • Jeong, Hyun Keun;Jeong, Hyun Do;Nam, Ki Chang;Kim, Ho Chul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.9
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    • pp.117-124
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    • 2015
  • In this paper, we introduce how to control TR, TE physical MR parameters for managing $H_1$ spin's SI(Signal Intensity) which is combined with gadolinium following administration MR agent in T1 effect for diagnostic usefulness. we used MRI phantom made with 0.5 mol Gadoteridol. This phantom was scanned by FSE sequence with different TR, TE parameters. In this study, to make T1 effect, TR was 200, 250, 300, 350, 400, 450, 500, 550, 600 msec. In addition to, TE was 6.2, 12.4, 18.6, 21.6 msec. The results were as follows ; Each RSP(Reaction Starting Point) was 100, 50, 40, 30 mmol in TE 6.2, 12.4, 18.6, 21.6 msec being irrelevant to TR. In MPSI(Max Peak Signal Intensity), 4 mmol was showed in TR 200 msec while peak signal was decreased to low concentration mol in TR 250-600 msec. In terms of RA(Reaction Area), the highest SI was TE 6.2 msec in TR 200-600msec. According to the study, we are able to recognize it is possible to control enhance rates by managing TR and TE of MR parameters; moreover, we expect that enhanced T1 image in MR clinical field can be performed in a practical way with this quantitative data.

High-Resolution of Paleoenvironmental Reconstruction and Sea-Level History in Delaware Bay, the East Coast of U.S.A. (미국동부 델라웨어만의 고정밀도 해수면 역사와 고환경 복원)

  • YI, HI-IL;WEHMILLER, JOHN F.
    • 한국해양학회지
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    • v.30 no.4
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    • pp.320-331
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    • 1995
  • The closely spaced cores were analyzed to find detailed reconstruction of paleoenvironments and sealable changes along the Delaware Bay coast. Three areas, Kitts Hummock Beach mars, the St. Jones River marsh, and Bowers marsh near the St. Jones River's mouth, were chosen because these areas are compose of their own geomorphic characteristics and sea-level history. since significance of the stratigraphic correlations was to determine sedimentary fancies and paleoenvironments, multidisciplinary methods such as lithological description, grain-size analysis, organic/inorganic content, water content, mineral composition, botanical analysis, micropaleontological analysis, and /SUP 14/C datings were performed. Five major divisions of marsh environments were recognized in the stratigraphic sections: freshwater marsh, initialfreshwater marsh, slightly brackish marsh, brackish marsh, and salt marsh. Most of the lower part in the stratigraphic sections show freshwater marsh. On the top of this, either brackish marsh or tidal flat/tidal stream was recorded. The pro-Holocene sediments consist of sand, mud, and sandy mud, The pre-Holocene configuration played an important role for developing the Holocene Paleoenvironmental changes. The irregular configuration of the pre-Holocene sediments consist of sand, mud, and sandy mud. The pre-Holocene configuration played an important role for developing the Holocene Paleoenvironmental changes. The irregular configuration of the pre-Holocene surface within short distances permitted the concurrent development of variable environments such as freshwater marsh, brackish marsh or salt marsh at similar elevations. The freshwater marsh in this case was formed in the areas of isolation, so saline-water cannot encroach upon these areas. This complex development of paleoenvironments leads to a difficulty in stratigraphic correlation and interpretation of local relative sea-level changes. The deposition of subsurface sediments was affected by sediment supply, compaction, fluvial activity, biological competition, local tectonics and isostacy, climate and local relative sea-level changes. It was interpreted that the positions in the changes from freshwater environments to brackish environments or ice versa are the turning points of transgressions and regressions. Therefore, multiple transgressions and regressions were identified in the stratigraphic sections of the study area.

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Analysis of Relativity Between Invasiveness on Chest of Tomographic Finding and Histopathologic Invasiveness (종격동 종양의 전산화 단층촬영(CT)소견, 수술소견 및 병리조직학적 침윤도 사이의 상관성 분석)

  • 김용희;이현우
    • Journal of Chest Surgery
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    • v.30 no.8
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    • pp.780-785
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    • 1997
  • Mediastinal tumor had been fascinated by its location on heart, great vessels, esophagus, and nervous tissue, its convenience of surgical treatment and superiority of its operative result. Between January 1989 and June 1995, eighty-seven patients with mediastinal tumor which were treated surgically in the Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, School of Medicine, University of Ulsan. To provide the appropriate surgical management of mediastinal tumor, the demographic data, diagnostic evaluation, clinical presentation, location, size, operative finding and histopathologic distribution were reviewed and we analyzed relativity between invasiveness in chest computed tomographic finding or invasiveness on operative finding and histopathologic invasiveness. The anterosuperior mediastinum was the most commonly involved site of a mediastinal tumor(57%), followed by the posterior mediastinum(35%) and middle mediastinum(8%). The most frequently encountered tumors were thymic neoplasia(31%), followed by primary cyst(22%), neurogenic tumor(22%) and teratoma(10%) in decreasing order of frequency. Histopathologically invasive tumors were present in 17 patients(20%) and its site included anterosuperior mediastinum(16%) and posterior mediastinum(4%). All patients in this study underwent chest CT. In chest CT's finding, 15 patients(17%) showed invasiveness. A total excision of the tumor was performed 80 patients(92%), subtotal excision 6 patients(7%) and biopsy only 1 patient(2%). In operative finding, 14 patients(16%) were suspected invasiveness. The mean size of the tumor was 6.0$\pm$ 3.2cm. In anterosuperior mediastinum, the mean size was 6.2$\pm$3.1cm, in middle mediastinum, it was 3.9$\pm$1.1cm, in posterior mediastinum, it was 5.8$\pm$2.6cm. In malignant tumors, the mean size was 7.3$\pm$4.6cm, in benign tumor, it was 5.5$\pm$2.6cm(P<0.05). Relativity between histopathological invasiveness(17 patients) and invasiveness in chest CT's finding(15 patients) included sensitivity 35%, specificity 87% and predictability 35%, relativity between histopathological invasiveness(17 patients) and invasiveness on operative finding included sensitivity 52%, specificity 93% and predictability 64%. In conclusion, since it was proved that the compatibility of preoperative chest CT findings or operative findings and histopathological invasiveness is quite low, it is considered that wide excision of the mediastinal tumor except cystic lesion including adjacent tissues would yield better postoperative results.

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Exogenous DNA Transfer by Intracytoplasmic Sperm Injection in Porcine Oocytes (돼지에 있어서 난자내 정자 직접 주입에 의한 외래 유전자 도입에 관한 연구)

  • Ahn, S. Y.;Lee, H. T.;K. S. Chung
    • Korean Journal of Animal Reproduction
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    • v.25 no.4
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    • pp.339-347
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    • 2001
  • Sperm-mediated DNA transfer has a potential to markedly simplify techniques for the generation of transgenic animals. The exogenous DNA transfer by intracytoplasmic sperm injection (ICSI) procedure has been recently introduced in the production of transgenic animals. In this study, the developmental competence and tile expression rates of transgene were investigated after injection of spermatozoon or sperm head with enhanced green fluorescent protein (EGFP) gene into the mature porcine oocytes. The porcine oocytes were injected with intact sperm, membrane-disrupted sperm or sperm head. After injection. embryos were cultured in NCSU23 medium up to the blastocyst stage, and the developmental competence and expression rates were studied. The developmental rate (67.0%) of sperm injection group was higher than that (59.7%) of sperm head injection group, and the rates of EGFP expression were also significantly different between sperm injection and sperm head injection groups (42.1 vs 20.0%) (F<0.05). In the porcine oocytes injected with sperm treated with different methods of membrane disruption, the removal of sperm membrane did not alter the developmental competence of embryos. The rate of blastocysts at 7 days after injection with intact and membrane disrupted sperm were 15.0 and 14.2%, respectively. The EGFP expression rates, 38.4% in embryos injected with frozen-thawed sperm was higher than that, 22.4% of embryos injected with the Triton X-100 treated sperm. Prior to injection, sperm were cultured in different EGFP gene concentrations from 0.Ol to 1ng/u${mu}ell$. However, no significant difference in developmental rates of embryos among different concentrations of EGFP gene were observed. The highest expression rate of EGFP gene, 37.4% was obtained from the embryos injected with spermatozoa treated with 0.1 ng/${mu}ell$ EGFP gene. These results suggested that exogenous DNA could be attached to the membrane disrupted sperm, and that these sperm could be used as a vector carrying foreign DNA into embryos.

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Effects of Removal Times of Transplanted Pituitary Gland on Induction of Ovulation and Levels of Estrogen and Progesterone in Immature Rats (미성숙 쥐에 이식한 뇌하수체의 경시별제거가 배란유도와 Estrogen 및 Progesterone수준에 미치는 영향)

  • Lee, J. H.;Kim, Y. H.;Lee, W.
    • Journal of Embryo Transfer
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    • v.2 no.1
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    • pp.36-46
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    • 1987
  • The present work was designed to understand the mechanism of superovuiation and the cause of early embryo loss and Implantation failure in the superovulating immature female rats which were elaborated by a pituitary gland transplantation. A pituitary gland obtained from the orchidectomized rats was transplanted under the right kidney capsule of 28 day old female rats (PGT group) on the starting day of experiment which was designated as Day 2. The grafted pituitary glands were removed at 6h (RPGT 6h group), 12h (RPGT 12hgroup) and 24h (RPGT 24h group) after the transplantation. Control rats were treated with 41U PMSG on Day 2 (PMSG group). The estrous cycle and the levels of plasma progesterone and estradiol-17$\beta$ were observed on Day 0, Day 5, respectively. The implantation sites, the weights of ovary and uterus, and the number of corpora lutea were examined in all group on Day 8. The resuft obtained were summarized as follows: 1. The percentages of the number of the rats in proestrus and estrus were 93.0%, 82.6%, 0%, 90.7% and 89.5% in PMSG, PGT, RPGT6h, RPGT12h and RPGT24h group, respectively. The synchronization of estrus cycle was dchieved in all groups. 2. The mating rates of each group were 80.2, 75.0, 0, 56.4, 57.8% in PMSG, PGT, RPGT6h, RPGT12h, RPGT24h group, respectively. 3. The numbers of copora lutea on Day 8 were 47.1 i 4.9, 18.1 $\pm$0.5, 14.1 i 0.3 and 8.9 $\pm$ 0.3 in PGT, RPGT24h, RPGTl2h and PMSG group, respectively. There were signIficantly difference between all groups (P<0.05). 4. The numbers of implantation sites (18.1 +- 4.0) in PGT group on Day 8 were higher than those of PMSG (8.5 $\pm$ 2.5), RPGT 12h (9.8 i 0.2) and RPGT 24h group (10.8 i 0.2) (P<0.05). 5. The ovarlan weights in PGT (95.2 $\pm$ 14.3mgIlOOg BW), RPGT 12h (51.7 $\pm$ 0.6mgIlOOg BW), and RPGT24h (57.9 $\pm$ 0.9mg/l00g 8W) groups were significantly higher than those of PMSG group (30.4 $\pm$7.4mg/l00g BW) (P<0.05). 6. The uterine weights in PMSG (672.4 $\pm$ 4.7mg/l00g 8W), and PGT (660.7 $\pm$7.8mg/l00g BW) groupswere greater than those of RPGT 12h (403.0 $\pm$ 1.lmg/lOOg BW) and RPGT 24h (490.1 $\pm$ 0.9mg/l00g BW) group (P<0.05). 7. The plasma progesterone levels in PGT groups (15 lng/ml) on Day 5 were higher than those of PMSG (83ng/ml), RPGT 12h (S7ng/ml), RPGT24h (8lng/ml) group (P<0.05). 8. The plasma estradiol-17$\beta$ levels in PMSG group (lBSpg/ml) on Day S were higher than those of RPGT 24h (l3pg/ml) group (P<0.05). But estradiol-17$\beta$ levels in PGT and RPGT 12h group were too low to discuss.

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A Study on Artificial Radionuclides(134Cs, 137Cs and 239+240Pu) Distribution in the Sediment from Lake Euiam (의암호 퇴적물 내 인공방사성동위원소 (134Cs, 137Cs, 239+240Pu) 분포특성 연구)

  • Kim, Seung Hwan;Lee, Sang-Han;Oh, Jung Suk;Choi, Jong Ki;Kang, Tae Gu
    • Journal of Radiation Protection and Research
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    • v.40 no.4
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    • pp.223-230
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    • 2015
  • The objective of this study is to identify the radionuclide distribution in public water by carrying out the analysis of artificial radionuclides($^{134}Cs$, $^{137}Cs$, $^{239+240}Pu$), natural radionuclide($^{210}Pb$) and TOC in the lake Euiam sediment in Chuncheon, South Korea. The $^{134}Cs$ concentration in all lake sediments showed below MDA values, and the $^{137}Cs$ concentration in lake sediment were ranged from MDA to $8.79Bq{\cdot}kg^{-1}-dry$. The $^{137}Cs$ concentrations in surface sediment were reported to be 2.4 to $4.2Bq{\cdot}kg^{-1}-dry$. The lowest concentration of $^{137}Cs$ was reported at St. 4 and the highest concentration was reported at St. 3, respectively. The $^{239+240}Pu$ concentration in lake sediment were ranged from 0.049 to $0.47Bq{\cdot}kg^{-1}-dry$. The lowest concentration was reported at St. 2 and the highest concentration was reported at St. 3. The correlation(r) between the $^{239+240}Pu$ concentration and $^{137}Cs$ concentration in lake sediment presented higher values (0.54 to 0.97) and this suggests the behavior and origin of $^{137}Cs$ is identical to the $^{239+240}Pu$ in the sediment. The $^{134}Cs$ concentration below MDA value and the $^{239+240}Pu/^{137}Cs$ ratio(mean value of 0.041) indicated that the artificial radionuclides in the sediment were originated from global fallout by the atmospheric testing of nuclear weapons conducted by former USSR and U.S.A, but not from the Fukushima Daiichi NPP accident. The sedimentation rate derived from $^{210}Pb$ age-dating method at St. 2 is calculated to be $0.31{\pm}0.06cm{\cdot}y^{-1}$. This value is similar to the value ($0.41{\pm}0.05cm{\cdot}y^{-1}$) estimated from the $^{137}Cs$ maximum peak produced from early 1960's. The content of TOC in lake Euiam sediments varied from 0.20 to 13.01%. While the highest correlation between TOC and $^{137}Cs$ concentration in the sediment were found at St. 1, the others presented the low correlation.

Comparative Molecular Phylogenetic Relationships in Different Strains of Pleurotus spp. (느타리속 버섯 계통의 분자생물학적 유연관계의 비교연구)

  • Cho, Hae-Jin;Lee, Jae-Seong;Yoon, Ki-Nam;Alam, Nuhu;Lee, Kyung-Lim;Shim, Mi-Ja;Lee, Min-Woong;Cheong, Jong-Chun;Shin, Pyung-Gyun;Yoo, Young-Bok;Lee, U-Youn;Lee, Tae-Soo
    • The Korean Journal of Mycology
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    • v.38 no.2
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    • pp.112-119
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    • 2010
  • Pleurotus spp. have been used for edible and medicinal purposes in Asian countries for a long time. The fruiting bodies of the Pleurotus ostreatus, Pleurotus citrinopileatus and Pleurotus salmoneostramineus contained many physiologically beneficial substances for human health. Therefore, it is necessary to study the genetic diversity of Pleurotus mushroom cultivars commercially cultivated in Korea. Eleven strains of Pleurotus spp. were collected from different geographical regions in South-East Asia and ITS regions of rDNA and RAPD of genomic DNA were analyzed. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 167 to 254 bp and 156 to 213 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, and the 5.8S sequences were identical. A phylogenetic tree based on the ITS region sequences indicated that selected strains could be classified into 4 clusters. Eleven Pleurotus species were also analyzed by RAPD with 20 arbitrary primers. Ten of these primers were efficiently amplified the genomic DNA. The number of amplified bands varied with the primers and strains, with polymorphic fragments in the range from 0.1 to 2.0kb. The results revealed that genetic diversity of selected strains of P. ostreatus, P. citrinopileatus and P. salmoneostramineus is low.

Blood Pressure of Healthy Newborns in the First Week of Life (분당 차병원에서 출생한 신생아 혈압치 비교)

  • Lee Jung-Sun;Park Shin-I;Park Hye-Won;Kim Se-Hyun;Hah Tae-Sun;Lee Jun-Ho
    • Childhood Kidney Diseases
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    • v.9 no.1
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    • pp.8-14
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    • 2005
  • Purpose : This study was peformed to study normative blood pressure data in full-term neonates that may be used to facilitate Identification of neonatal hypertension.Methods : 383 newborns born in our hospital from May 2003 to January 2004 were enrolled in this study Using an oscillometric device(BP-88 NEXT, COLIN Corp.), their blood pressures were measured more than one time within a week after birth. According to each clinical variable such as sex, delivery mode, birth weight, gestational age and presence of maternal disease or perinatal problems, we divided the population into groups and calculated the mean blood pressures of each group. We compared mean blood pressures between the divided groups according to each clinical variable statistically.Results : Mean systolic and diastolic blood pressure of the Population was 70.8$\pm$ 10.9 mmHg and 43.4 $\pm$ 8.0 mmHg, respectively. There was no satistically significant difference in blood pressure according to clinical variables. Mean systolic pressure showed positive correlation with birth weight and gestational age(r=0.1420, 0.03130).Conclusion : Our results are almost in agreement with Zubrow's data from 695 newborns in U.S.A, 1995. Our data may be helpful for early detection and management of neonatal hypertension, thereby maintaining renal function ,and preventing possible complications of renal disease.

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A Study on the Characteristics of Jobs in Academic Libraries According to Different Generations (대학도서관 업무의 시대별 변천에 따른 특성 연구)

  • Cho, Chul-Hyun
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.26 no.1
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    • pp.135-170
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    • 2015
  • This study aimed to investigate the transition of academic libraries' jobs by developing a model based on a shift of library generations including Library 1.0, Library 2.0, and Library 3.0 corresponding to the shift of web generations and to explore generational characteristics of library duties as well. The research used three phases of procedure: literature review about different library generations; job analyses for academic libraries in South Korea and the U.S.A.; the Delphi technique in tree sequential order. The research findings were as follows. First of all, there were 170 duties that continued from Library 1.0 to Library 3.0. There were 58 duties which continued from Library 2.0 to Library 3.0 whereas three duties that continued from Library 1.0 to Library 2.0. In addition, three distinctive duties existed only in Library 1.0 whereas one unique duty was only in Library 2.0. Library 3.0 generated 25 new duties. Secondly, considering general characteristics which cover specific parts of individual duties, there was a significant increase in importance, difficulty, and frequency of library administration throughout the three generations. In terms of importance, difficulty, and frequency of collection development and management, there was a significant increase only from Library 2.0 to Library 3.0. Considering information organization, there was a significant decrease in importance from Library 1.0 to Library 2.0. In addition, there was a significant decrease in frequency and there was no significant difference in difficulty throughout the three generations. In the case of information service, while there was a significant increase in importance among three generations, there was a significant increase in difficulty only from Library 1.0 to Library 2.0. However, there was no generational difference in frequency. With the respect of information system development and management, there was a significant increase in importance and frequency throughout the three generations, but there was no significant difference in difficulty among three generations.

A STUDY ON IN VIVO AND IN VITRO AMALGAM CORROSION (아말감의 구강내 부식 및 인공 부식에 관한 연구)

  • Lim, Byong-Mok;Kwon, Hyuk-Choon;Um, Chung-Moon
    • Restorative Dentistry and Endodontics
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    • v.22 no.1
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    • pp.1-33
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    • 1997
  • The objective of this study was to analyze the in vitro and in vivo corrosion products of low and high copper amalgams. The four different types of amalgam alloy used in this study were Fine cut, Caulk spherical, Dispersalloy, and Tytin. After each amalgam alloy and Hg were triturated according to the directions of the manufacturer by means of the mechanical amalgamator(Amalgam mixer. Shinhung Co. Korea), the triturated mass was inserted into a cylindrical metal mold which was 12mm in diameter and 10mm in height. The mass was condensed by 150Kg/cm compressive force. The specimen was removed from the mold and aged at room temperature for about seven days. The standard surface preparation was routinely carried out by emery paper polishing under running water. In vitro amalgam specimens were potentiostatically polarized ten times in a normal saline solution at $37^{\circ}C$(potentiostat : HA-301. Hukuto Denko Corp. Japan). Each specimen was subjected to anodic polarization scan within the potential range -1700mV to+400mV(SCE). After corrosion tests, anodic polarization curves and corrosion potentials were obtained. The amount of component elements dissolved from amalgams into solution was measured three times by ICP AES(Inductive Coupled Plasma Atomic Emission Spectrometry: Plasma 40. Perkim Elmer Co. U.S.A.). The four different types of amalgam were filled in occlusal and buccal class I cavities of four human 3rd molars. After about five years the restorations were carefully removed after tooth extraction to preserve the structural details including the deteriorated margins. The occlusal surface, amalgam-tooth interface and the fractured surface of in vivo amalgam corrosion products were analyzed. In vivo and in vitro amalgam specimens were examined and analyzed metallographically by SEM(Scanning Electron Microscope: JSM 840. Jeol Co. Japan) and EDAX(Energy Dispersive Micro X-ray Analyser: JSM 840. Jeol Co. Japan). 1. The following results are obtained from in vitro corrosion tests. 1) Corrosion potentials of all amalgams became more noble after ten times passing through the in vitro corrosion test compared to first time. 2) After times through the test, released Cu concentration in saline solution was almost equal but highest in Fine cut. Ag and Hg ion concentration was highest in Caulk spherical and Sn was highest in Dispersalloy. 3) Analyses of surface corrosion products in vitro reveal the following results. a)The corroded surface of Caulk spherical has Na-Sn-Cl containing clusters of $5{\mu}m$ needle-like crystals and oval shapes of Sn-Cl phase, polyhedral Sn oxide phase. b)In Fine cut, there appeared to be a large Sn containing phase, surrounded by many Cu-Sn phases of $1{\mu}m$ granular shapes. c)Dispersalloy was covered by a thick reticular layer which contained Zn-Cl phase. d)In Tytin, a very thin, corroded layer had formed with irregularly growing Sn-Cl phases that looked like a stack of plates. 2. The following results are obtained by an analysis of in vivo amalgam corrosion products. 1) Occlusal surfaces of all amalgams were covered by thick amorphous layers containing Ca-P elements which were abraded by occlusal force. 2) In tooth-amalgam interface, Ca-P containing products were examined in all amalgams but were most clearly seen in low copper amalgams. 3) Sn oxide appeared as a polyhedral shape in internal space in Caulk spherical and Fine cut. 4) Apical pyramidal shaped Sn oxide and curved plate-like Sn-Cl phases resulted in Dispersalloy. 5) In Tytin, Sn oxide and Sn hydroxide were not seen but polyhedral Ag-Hg phase crystal appeared in internal space which assumed a ${\beta}_l$ phase.

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