• Title/Summary/Keyword: Ni

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Comparison of shaping ability using various Nickel-Titanium rotary files and hybrid technique (다양한 전동 니켈 티타늄 파일과 혼합사용법에 의한 근관 성형 효율 비교)

  • Kim, Jung-Won;Park, Jeong-Kil;Hur, Bock;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • v.32 no.6
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    • pp.530-541
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    • 2007
  • Currently, various Nickel-Titanium rotary files are used in endodontic treatment, but there is no one perfect system that can be applied to any clinical situation. Therefore, the combined uses of various file systems which can emphasize the advantages of each system are introduced as hybrid instrumentation. The ProTaper system is efficient in body shaping and apical pre-enlargement but is reported to have more possibility of transportation and produce more aberrations and deformation in more or less severe curved canals. Recently, new ProTaper system(ProTaper Universal) with different configuration and cross-sectional design to overcome the week points of ProTaper have been marketed. The purpose of this study was to compare and evaluate the shaping abilities of ProTaper, ProTaper Universal system, and two hybrid methods using S-series of ProTaper Universal and Hero Shaper or ProFile. The time lapses for instrumentation were measured and the used files were inspected for distortion. The pre- and post-instrumented root canals were scanned and superimposed to evaluate the aberrations and reduction of root canal curvature and change of radius of canal curvature. The increased canal width and apical centering ratio were calculated at 1, 2, 3, 4 and 5 mm levels from apical foramen. Under the conditions of this study, the ProTaper Universal seems to have better shaping ability than ProTaper in terms of instrumented width and instrumentation time. It may be suggested that the ProTaper Universal system is efficient as much as hybrid instrumentation using ProTaper and other constant-tapered NiTi file systems in highly experienced operators.

A comparative study on the fracture behavior of zironia, glass infiltrated alumina and PFM full crown system (지르코니아, 유리침투알루미나 및 PFM 전부관 시스템의 파절 경향에 관한 비교연구)

  • Lee, Sang-Hyeok;Ahn, Jin-Soo;Kim, Myung-Ho;Lim, Bum-Soon
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.4
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    • pp.235-242
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    • 2012
  • Purpose: The purpose of this study was to compare the fracture behavior of Zironia, glass infiltrated Alumina and PFM full crown system. Materials and methods: Fifteen crowns for each of 3 experimental groups (Zironia, glass infiltrated Alumina and PFM full crown) were made by the conventional method. The crowns mounted on the testing jig were inclined in 30 degrees to the long axis of the tooth and the universal testing machine was used to measure the fracture strength. Results: 1. The mean fracture strengths were $588.3{\pm}49.6MPa$ for zirconia system, $569.1{\pm}61.8MPa$ for PFM system and $551.0{\pm}76.5MPa$ for glass-infiltrated alumina system (P>.05). 2. The mean shear bond strengths were $25.5{\pm}5.6MPa$ for zirconia system, $38.9{\pm}5.0MPa$ for Ni-Cr alloy system and $39.4{\pm}5.1MPa$ for glass-infiltrated alumina system. 3. The chemical bonding was observed at interfaces between PFM or glass-infiltrated alumina and veneering porcelain, however, no chemical bonding was observed at interface between zirconia and veneering porcelain. Conclusion: With the study, the fracture strengths of PFM crown system had a higher fracture strength than conventional zirconia system crown and glass-infiltrated alumina crowns. and than the shear bond strengths glass-infiltrated alumina system had a higher shear bond strength than conventional PFM system and zirconia system.

Optimization of Human Thrombopoietin Production in Insert Cells Using Baculovirus Expression System (베큘로 바이러스 발현 시스템에 의한 곤충세포에서의 인간 트롬보포이에틴 생산 최적화)

  • 고여욱;손미영;박상규;안혜경;박승국;박명환;양재명
    • KSBB Journal
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    • v.13 no.2
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    • pp.181-186
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    • 1998
  • In order to obtain high-level production of recombinant human thrombopoietin (rhTPO) in insect cell line, HTI-TN-5B1-4 (TN5), conditions for optimal rhTPO expression such as multiplicity of infection (MOI), the cell density at infection, harvesting time and type of culture method as well as growth media were determined. When TN5 cells were cultured as anchorage-dependent state in 60-mm dish, cell density $2\times^6$ cells,MOI of 10 and Garvesting the culture media at 72 hr post-infection wrere the cinditions for highest rh TPO production. High production of rhTPO was also achieved by using EXPRESS FIVE serum free media rather than SF900II serum free media-1. Anchorage-dependent TN5 cells were adapted as a suspension culture when they were grown in the presence of heparin. TN5 cells were successfully cultured at 0.2 L scale in suspension culture without having aggregation. When TN5 cells were cultured as suspension state, cell density of $0.6\times10^6$ cells/mL, MOI of 1 and harvesting the culture media at 72 hr post-infection, gave the highest yield of rhTPO.

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A Study on Heavy Metal Concentrations of Oxidized Hair Coloring Products in Korea Market (한국에서 유통 중인 산화형 염모제의 중금속 농도에 관한 연구)

  • Choi, Chae Man;Hong, Mi Sun;Lee, Yun Jung;Kim, Hwa Soon;Kim, Hyun Jung;Kim, Jung Hun;Chae, Young Zoo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.3
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    • pp.241-249
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    • 2013
  • This study was aimed to provide the fundamental data about oxidized hair color products. For this reason, we collected 125 oxidized hair color products, which were distributed in domestic market from January to October, 2012, and measured the heavy metal concentrations of lead, arsenic, cadmium, chromium, manganese, nickel, copper in the samples. Results were compared by domestic, foreign, henna, type and color. The average metal concentrations were as follows; 0.211 ${\mu}g/g$ for lead, 0.008 ${\mu}g/g$ for cadmium, 0.051 ${\mu}g/g$ for arsenic, 0.954 ${\mu}g/g$ for chromium, 6.250 ${\mu}g/g$ for manganese, 0.591 ${\mu}g/g$ for nickel and 0.544 ${\mu}g/g$ for copper. In case of lead and arsenic, the concentrations were much less than the regulated amount (20 ${\mu}g/g$ and 10 ${\mu}g/g$, respectively) suggested by MFDS (Ministry of Food and Drug Safety). In henna (p < 0.05), the concentrations were significantly higher than those of other domestic and foreign oxidized hair color products as follows; 1.264 ${\mu}g/g$ for lead, 0.267 ${\mu}g/g$ for arsenic, 0.025 ${\mu}g/g$ for cadmium, 4.055 ${\mu}g/g$ for chromium, 72.044 ${\mu}g/g$ for manganese, 3.076 ${\mu}g/g$ for nickel and 4.640 ${\mu}g/g$ for copper. Statistically, it showed that the heavy metal concentrations were quite different for the different types of hair color products. The cream and liquid type products had the highest average concentration in chromium (0.708 ${\mu}g/g$, 0.478 ${\mu}g/g$, respectively). On the other hand, powder type products showed the highest concentration in manganese (60.041 ${\mu}g/g$). In addition, the concentrations of heavy metals and the color of products are not quite correlated. It was shown that average concentrations of lead and chromium were higher for yellow, chromium for red and pink, manganese for brown and black, and nickel for green.

Low Dilution Glass Bead Digestion Technique for the Trace Element Analysis of Rock Samples (저희석 유리구 용해법에 의한 암석시료 미량원소 분석법)

  • Park, Chan-Soo;Shin, Hyung-Seon;Oh, Hae-Young;Moon, Jong-Hwa;Cheong, Chang-Sik
    • The Journal of the Petrological Society of Korea
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    • v.20 no.3
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    • pp.161-172
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    • 2011
  • Open beaker digestion method is routinely used as the sample preparation technique for trace element determination of rock samples by inductively coupled plasma mass spectrometry, With this method, however, dissolution of Zr and Hf is not always guaranteed especially when the samples contain refractory minerals. In this study, glass bead digestion technique was compared with conventional open beaker digestion technique for the sample preparation of three USGS rock standards such as AGV-2, BHVO-2, and G-3. Thirty trace elements including rare earth elements were analysed by ICP-MS and ICP-AES. There were no clear differences in analytical results for the AGV-2 and BHVO-2 standards between the two techniques, but Zr, Hf, Y, and middle- to heavy- rare earth element concentrations of the G-3 standard prepared by open beaker digestion technique were significantly lower than the recommended values. This can be attributed to the presence of refractory mineral zircon. On the contrary, all the analytical results of the G-3 standard prepared by glass bead digestion technique were in good agreement with the recommended values, indicating complete dissolution of zircon. The analytical results show that the volatile elements such as Pb and Zn were not lost during the preparation of glass bead. Low dilution glass bead digestion technique described here will be very helpful to enhance precision and accuracy of trace element analysis for geological samples containing refractory minerals.

The Effect of Deodeok Contents on the Quality of Deodeok Wine (더덕 함량이 더덕 침출주의 품질에 미치는 영향)

  • Kwon, Dong-Jin;Choi, Shin-Yang
    • Food Science and Preservation
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    • v.14 no.4
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    • pp.414-418
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    • 2007
  • The physicochemical characteristics and sensory properties of Deodeok wine, formed by leaching of Deodeok at room temperature for 180 days, were investigated over the following range of Deodeok levels: 10, 15 and 20% (all w/v). The higher the level of Deodeok, the greater were the final values of total sugars, reducing sugars, total polyphenols, and crude saponins. The Hunter's b-value (yellowness) of Deodeok wine varied markedly with Deodeok levels, and yellowness was highest in Deodeok wine containing 20% (w/v) Deodeok. Non-volatile compounds, that form the basis of the liquor tax law, were 0.64, 1.38 and 2.11% (all w/v), respectively, at day 160. Of these values, that of 2.11% (w/v), the level of non-volatile compounds in Deodeok wine containing 20% (w/v) Deodeok, was in accord with the liquor tax law (that requires this figure to be 2.0%). Sensory evaluation showed that Deodeok wine containing 20% (w/v) Deodeok was superior to the other wines tested.

Effect of estrogen on growth hormone receptor expression of human periodontal ligament cell line (치주인대세포 배양에서 estrogen이 growth hormone receptor의 발현유도에 미치는 영향)

  • Hong, Sung-Gyu;Jeon, Young-Mi;Kim, Jong-Ghee
    • The korean journal of orthodontics
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    • v.30 no.4 s.81
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    • pp.441-452
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    • 2000
  • The present studies were performed to investigate the interaction of $17{\beta}$-estradiol and human growth hormone(hGH) on the proliferation of human periodontal ligament(WDL) cell. The independent effects of $17{\beta}$ estradiol and hGH on hPDL cell proliferation were investigated and the effects of hGH on hPDL cell proliferation after $17{\beta}$-estradiol pre-treatment were also investigated. Lastly, the change of hGH receptor expression in hPDL cell after $17{\beta}$-estradiol pre-treatment were investigated. The obtained results were as follows; 1. The treatment of $17{\beta}$-estradiol or hGH had no significant effects on hPDL cell proliferation. 2. After pre-treatment of $17{\beta}$-estradiol, hGH stimulated the proliferation of the hPDL cell, regardless of hHG concentration. 3. Although there was not hGH receptor in the hPDL cell, hGH receptors were expressed in hPDL cell after more than 6 hours pre-treatment of $17{\beta}$-estradiol. 4. The effect of hGH on hPDL cell proliferation was related to the hGH receptor expression. $17{\beta}$-estradiol pre-treaaent contributed to the hGH effects on the hPDL cell by stimulating hGHR expression.

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The Side Effects and Correlates of OROS-Methylphenidate in the Treatment of Children and Adolescents with ADHD (ADHD 환자에 대한 OROS-Methylphenidate 약물치료의 부작용과 관련요인들에 대한 연구)

  • Kim, Jin-Sun;Kim, Bung-Nyun;Cho, Soo-Churl;Shin, Min-Sup;Yoo, Hee-Jeong;Kim, Jae-Won;Song, Dong-Ho;Shin, Dong-Won;Joung, Yoo-Sook;Cheon, Keun-Ah;Shin, Yee-Jin;Kim, Ye-Ni;Ha, Eun-Hye
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.21 no.2
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    • pp.63-71
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    • 2010
  • Objectives : The aim of this study was to investigate the effect of the clinical and demographic variables such as body weight, dosage, family history of attention-deficit hyperactivity disorder (ADHD), and psychiatric co-morbidity on the side-effects of OROS-Methylphenidate (OROS-MPH), and to evaluate the relationship between drug response and side effect severity. Methods : A total of 144 children (ages 6-18) with diagnosed ADHD were treated with OROS-MPH. Children were examined at baseline and after 1, 3, 6, 9, and 12 weeks of each treatment condition. The stimulant drug side effect rating scale (SERS), pulse rate, systolic blood pressure, diastolic blood pressure, and electrocardiogram (ECG) were evaluated to assess side effect profiles. Changes in these parameters from baseline were examined and analyzed. Results : Anorexia (30.95%) and insomnia (13.10%) were the most commonly reported side effects during this study. Insomnia and loss of appetite score increased at one week follow-up, but was sustained or decreased as treatment progressed. Small but significant increases in pulse rate and diastolic blood pressure were observed during treatment ; however, no clinically meaningful changes in ECG parameters were noted during the study. Low body weight, high dosage of OROS-MPH, and family history of ADHD were associated with cardiovascular side effect. In contrast, there was no significant relationship between OROS-MPH treatment response and the severity of side effect and no difference resulted between the responder and non-responder groups with respect to OROS-MPH dosage in the 12 weeks of follow-up. Conclusion : To the best of our knowledge, this study is the first Korean study to investigate comprehensive side effect profiles and their correlates in OROS-MPH treatment for ADHD children. OROS-MPH was well tolerated with no clinically significant side effects during the treatment period. In conclusion, low body weight, high dosage of OROSMPH, and family history of ADHD could be used as predictive factors in increasing pulse rate and blood pressure.

Reproductive Cycle of the Echiuroid Worm Urechis unicinctus(von Drasche) in Southern Korea (한국산 개불, Urechis unicinctus (von Drasche)의 생식주기)

  • 최상덕;김호진;이원교;곽은주;윤호섭;라성주;이인곤
    • Journal of Aquaculture
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    • v.13 no.2
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    • pp.169-174
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    • 2000
  • Reproductive cycle of U. unicinctus was studied from September 1998 to August 1999, using gonadosomatic index (CSI) as an indicator. In November, the CSI values were maximum for male (6.2) and female (7.0), respectively; the values were lowest for them (1.0 and 0.5) during the successive february. Subsequently, they rapidly increased and attained peak by March-April. The values decreased again in both sexes and remained unchanged until August. The index increased in October to attain the peak by November. The CSI values clearly indicated that there are two spawning events in a year, namely the first one during April-May and the second one in December. Reproductive cycle was classified into the following successive stages: in female, multipication (January~February, June ~Setember), maturation (March~April, November), spent (May and December), degeneration and resting (June and January), and in male, multiplication January ~ february, June ~September), maturation (March~April, October~November), spent (May and December) and degeneration and resting (January and June). Histological observations revealed that oocytes in the ovary matured simultaneously in November and March. At the same time, the envelopes of matured testis became thinner than those in the early stage.

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Optimization of Cookie Preparation by Addition of Yam Powder (마분말 첨가 쿠키 제조조건 최적화)

  • Joo, Na-Mi;Lee, Sun-Mee;Jung, Hee-Sun;Park, Sang-Hyun;Song, Yun-Hee;Shin, Ji-Hun;Jung, Hyeon-A
    • Food Science and Preservation
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    • v.15 no.1
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    • pp.49-57
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    • 2008
  • This study was conducted to develop an optimal composite recipe for a cookie including yam powder that would be attractive to all age groups. Wheat flour was partially substituted by yam powder to reduce the content of wheat flour. This study has produced the sensory optimal composite recipe by making cookies, respectively with each 5 level of yam powder $(X_1)$, Sugar$(X_2)$, butter$(X_3)$, by C.C.D (Central Composite Design) and conducting sensory evaluation and instrumental analysis by means of RSM (Response Surface Methodology). Sensory items showed very significant values in color, softness, overall quality (p<0.01), flavor (p<0.05) and those of instrumental analysis showed significant values in lightness, redness (p<0.05), spread ratio, hardness (p<0.01). Also sensory optimal ratio of yam cookie was calculated at yam powder 37.35 g, sugar 50.75 g, butter 78.40 g and it was revealed that the factors of influencing yam cookie aptitude were in older of yam powder, butter, sugar.