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임플란트 식립 시 골질이 주입회전력에 미치는 영향에 관한 삼차원 유한요소 분석 (Effect of Bone Quality on Insertion Torque during Implant Placement; Finite Eelement Analysis)

  • 정재덕;조인호
    • 구강회복응용과학지
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    • 제25권2호
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    • pp.109-123
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    • 2009
  • 임플란트 골유착의 성공과 임플란트 안정성에서 가장 중요한 것은 골의 양과 질이며 안정성을 평가하는 방법 중 하나인 주입회전력도 골질에 영향을 받는다. 임플란트를 식립할 때 모터에서 생긴 힘이 임플란트에 전달되면 임플란트는 회전력(moment)과 축력(axial force)을 갖게 되고 임플란트와 접촉한 골에서는 절삭과 압박 그리고 마찰이 일어나 응력이 생기는데 이 때 측정되는 주입회전력(insertion torque)은 골질에 따라 다양하게 나타난다. 본 연구에서는 임플란트를 하악 소구치 부위 골에 식립하는 것을 가정하여 골질을 치밀골의 두께와 망상골의 밀도 그리고 하방 치밀골 존재 시로 나누고, 골의 응력과 변위를 소탄성 범위의 유한요소법으로 분석하고 유효응력(von Mises stress)과 회전력 그리고 축력을 비교 연구하여 골질이 주입 회전력에 미치는 영향을 평가하였다. 임플란트($Br{\aa}nemark$ MKIII.RP, ${\phi}3.75{\times}10.0mm$, Nobel Biocare, $G{\ddot{o}}teborg$, Sweden) 와 원통형 골모형(${\phi}9.5{\times}12.0mm$)의 유한요소 모형을 설계하고 변수로 상부 치밀골의 두께(0.5 mm, 1.5 mm, 2.5 mm)와 치밀골 하부에 망상골의 밀도($0.85g/cm^3$, $1.11g/cm^3$, $1.25g/cm^3$) 그리고 골모형 하부에 1 mm 두께의 치밀골 유무에 따라 총 7개의 모형을 만들었으며, 임플란트가 식립될 때 발생하는 유효응력과 축력 그리고 회전력을 시간대 별로 비교하였다. 임플란트 플랜지 하연이 골의 상부를 파고드는 300 msec, 중간 정도 들어간 550 msec, 완전히 들어가 플랜지 상면이 골 표면과 일치한 800 msec로 나누어 관찰하였을 때 축력은 500 msec 전후에서, 회전력은 800 msec 전후에서 최대값를 보였으며 유효응력 분포는 서로 비슷하였다. 이 같은 실험 결과를 바탕으로 축력을 영역 별로 비교하여 다음과 같은 결과를 얻었다. 1. $Br{\aa}nemark$ MKIII 임플란트는 플랜지가 골을 파고들 때 축력이 치밀 골에서 가장 높았고, 회전력은 플랜지가 골상부에 걸리어 축력이 급격히 감소한 이후에 최대 회전력을 보였으며, 이 때 유효응력 분포는 플랜지와 접촉하는 골 상부에 집중되었다. 2. 임플란트 식립 시 치밀골의 두께가 두꺼울수록 축력과 회전력이 높게 나타났으며 치밀골의 두께가 축력과 회전력에 가장 큰 영향을 주었다. 3. 치밀골의 두께가 1.5 mm 이상인 경우 망상 골의 밀도가 축력에 미치는 영향은 작았고, 치밀골의 두께가 0.5 mm인 경우 망상골의 밀도가 축력과 회전력에 영향이 있을 것으로 사료되었다. 4. 양측 피질골 존재 시 축력의 합은 상부 피질골의 두께가 같은 다른 경우와 비슷하였으나 부위별 촉력은 골하부에서 양측 피질골 모형이 가장 높았고, 회전력은 하방 피질골과 접촉할 때는 피질골 두께가 같은 다른 모형보다 다소 높으나 최대 회전력은 비슷하였다. 위 결과를 토대로 하악 소구치 부위에 $Br{\aa}nemark$ MKIII 임플란트 식립 시 골질과 관련된 요소 중에 치밀골의 두께가 주입회전력에 가장 큰 영향을 주며 망상골의 밀도를 높이는 술식도 일차적 안정성 증가에 유용할 것으로 사료되는 바이다.

극동러시아 남부의 국제 초국경 영역과 지속가능한 자원활용을 위한 역할 (International Transboundary Territories in the South of the Russian Far last and their Role in Sustainable Natural Resource Use in Border Regions)

  • Ganzei, S.S.;Mishina, N.V.
    • 대한지리학회지
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    • 제37권5호
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    • pp.522-535
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    • 2002
  • 소련의 붕괴 이후 지정학적 변화가 진행되면서 동아시아 국가의 통합이 증가하고 있다. 지리적 의미에서 외부 경제 연계의 성립은 둘 이상의 국가 간 국경 무역을 포함하는 특별한 영역에서 발생한다. 이러한 영역은 국제 초국경 영역으로 불리게 되었다. 본 논문에서는 국제 국경 영역의 특성을 분석하고 정의를 내린다. 극동 러시아의 남부에 위치한 국제 국경 영역을 몇 개의 구역으로 구분한다. 예를 들면. V.B. Sochava의 지오시스템(geosystem)체계에 기반한 위계적 분류를 행한다 이러한 국가의 국경 지역에서 지속가능한 자연 자원 이용 프로그램을 개발하기 위한 국경 영역에 대한 향후 연구 지침도 요약되어 있다.

Effects of D-Fructose on the Uptake of Iron by the Intestinal Brush-Border Membrane Vesicles from Rats.

  • Kim, Ok-Seon;Lee, Yong-Bok;Oh, In-Joon;Koh, Ik-Bae;Lee, Yeong-Woo
    • Journal of Pharmaceutical Investigation
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    • 제24권3호spc1호
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    • pp.11-18
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    • 1994
  • We have studied the iron uptake by the purified brush-border membrane vesicles (BBMVs) to determine the effect of fructose on the absorption of iron. BBMVs were prepared by the modified calcium precipitation method, The degree of purification was routinely assessed by the marker enzyme, alkaline phosphatase, and the functional integrity was tested by $D-[1-^3H]glucose$ uptake. The appearance of membrane vesicles was shown by transmission electron microscopy (TEM). The uptakes of complexes of labeled iron $[^{59}Fe]$ with fructose and ascorbate were measured with a rapid filtration technique, The uptake rate and pattern of the two iron-complexes, Fe(III)-fructose and Fe(III)-ascorbate, were also observed. A typical overshooting uptake of D-glucose was observed with peak value of $2{\sim}3$ times higher concentration than that at equilibrium. This result was similar to other studies with BBMVs. TEM showed that the size of BBMVs was uniform and we can hardly find any contaminants, Fe(III)-fructose has the higher value of $V_{max}$ and the lower value of Km than those of Fe(III)-ascorbate, respectively. It may be concluded that D-fructose is more effective in promoting the iron absorption than ascorbate.

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가토 신피질 Brush Border Membrane과 Basolateral Membrane Vesicle에서 유기이온의 이동에 대한 동력학적 분석 (Kinetics of Organic ion Transport Across Rabbit Renal Brush Border and Basolateral Membrane Vesicles)

  • 김용근;우재석;이상호
    • The Korean Journal of Physiology
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    • 제21권2호
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    • pp.273-282
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    • 1987
  • 가토 신피질에서 분리한 brush border membrane (BBM)과 basolateral membrane vesicle (BLM)에서 유기 음이온인 p-aminohippuric acid (PAH)와 유기 양이온인 tetraethylammonium (TEA)의 이동에 대한 동력학적 분석을 하였다. BLM에서 PAH에 대한 Km과 Vmax값은 각각 $0.34{\pm}0.02\;mM$$0.22{\pm}0.07\;nmol/mg\;protein/20s$였으며 BBM에서 각 값은 $8.46{\pm}0.57\;mM$$4.43{\pm}0.40\;nmol/mg\;protein/20s$였다. BLM에서 용액내 Na의 제거는 PAH에 대한 Km 값에는 영향없이 Vmax 값을 변화시켰다. BBM에서 TEA이동에 대한 Km과 Vmax 값은 각각 $0.55{\pm}0.15\;mM$$1.04{\pm}0.23\;nmol/mg\;protein/20s$였으며 BLM에서 각 값은 $0.46{\pm}0.04\;mM$$0.61{\pm}0.06\;nmol/mg\;protein/20s$였다. BLM에서 측정한 유기 이온들의 이동에 대한 Km 값이 신절편이나 분리된 tubule에서 보고된 값과 일치함을 보였으며 이러한 결과는 신세뇨관 세포막을 통한 유기 이온들의 이동 특성이 membrane vesicle을 분리하는 과정에서 변하지 않았음을 가르킨다.

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Inhibition of Dicarboxylate Transport by p-chloromercuribenzoic Acid (PCMB) in Plasma Membrane Vesicles of Rabbit Proximal Tubule

  • Kim, Yong-Keun;Kim, Tae-In;Jung, Jin-Sup;Lee, Sang-Ho
    • The Korean Journal of Physiology
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    • 제25권2호
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    • pp.179-188
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    • 1991
  • Effect of a sulfhydryl reagent, p-chloromercuribenzoic acid (PCMB), on the transport of succinate was studied in brush border (BBMV) and basolateral (BLMV) membrane vesicles isolated from rabbit renal cortex. PCMB induced an irreversible inhibition of the $Na^+-dependent$ succinate uptake in a dose-dependent manner with $IC_{50}$ of 55 and $65\;{\mu}M$ in BBMV and BLMV, respectively. The inhibitory effect of PCMB was prevented by a pretreatment of vesicles with dithiothreitol. PCMB did not increase $Na^+$ permeability at concentrations inhibiting succinate uptake. The PCMB inhibition of succinate uptake was due to a change in Vmax, but not in Km. When membrane vesicles were pretreated with PCMB in the presence of unlabelled succinate, the inhibitory effect was significantly reduced. In both BBMV and BLMV, succinate uptake was inhibited by various sulfhydryl reagents with the inhibitory potency of following order: $HgCl_2$>DTNB>PCMBS>PCMB. These results suggest that sulfhydryl groups are essential for dicarboxylate transport and that they may be located at or near substrate binding sites of the transporters in renal brush border and basolateral membranes.

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한국 전쟁 군사유적의 보호 및 활용에 관한 연구 - 중부접경지역(연천군, 철원군, 화천군)을 중심으로 - (Protection and Utilization of Military Remains during the Korean War - Focused on the Central Border of DMZ(Yeoncheon, Cheorwon, and Hwacheon-gun) -)

  • 조태환;김태영
    • 한국농촌건축학회논문집
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    • 제20권3호
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    • pp.47-56
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    • 2018
  • This study is to research the military remains of Korean War(1950~53) focused on Yeonchen, Cheorwon, and Hwacheon-gun in the central border of DMZ. The Yeoncheon-gun is installing 'Yeolsoe' and 'Taepung' observatory in the frontline battlefield adjacent to Southern Limit Line(SLL), and not only protects many military remains including war memorial and crematory facilities of UN troops, but also utilizes them as active educational places. The Cheorwon-gun is actively making known 'Baengmagoji memorial, 'Labor party office' and other buildings adjacent to 'Tourist security DMZ', but needs to set up many monuments around battlefields of 'Gimhwa' and 'Daeseongsan' adjacent to 'Eco-peace park DMZ'. With the battlefield of 'Paroho' as the center, which our troops made brilliant military gains during the war, the Hwacheon-gun protects and informs military remains such as '643 and 490 battlefields', 'Kkeomeok and Guman bridge'. Developing a network for military remains in connection with the annual local festivals, the experience tour and security will be available at these places.

새로 개발된 구내묘기장치에 의해 채득된 하악위와 측두하악관절잡음과의 관계 (Relationship of TMJ sound and mandibular positions recorded by a newly developed intra oral tracer)

  • 유강숙;최민호;김창현;박영록;강동완
    • 구강회복응용과학지
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    • 제19권2호
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    • pp.97-104
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    • 2003
  • It is clinically important to determine the physiologic mandibular position as the therapeutic position of the patients who needs the oral rehabilitation and occlusal treatment. Several methods have been employed for the recording the mandibular position. The gothic arch tracer is one of methods to record the mandibular position. The purpose of this study is to record the border position, chewing position, and myocentric position using the newly developed intra oral tracer in 10 subjects with TMJ clicking sound and 10 subjects without TMJ clinking sound.. This study showed that newly developed intra oral tracer allowed clinician the determination of the treatment position on the same horizontal plate which can be used in the full mouth rehabilitation and occlusal treatments. There was no statistically significant difference between clicking group and nonclicking group in the distance of border position-chewing position and the distance of border position-myocentric centric position.

Correlation of CT Perfusion Images with VEGF Expression in Solitary Brain Metastases

  • Zhang, Jian-Hua;Wang, Ming-Sheng;Pan, Hai-Hong;Li, Shu-Feng;Wang, Zhong-Qiu;Chen, Wang-Sheng
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권4호
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    • pp.1575-1578
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    • 2012
  • Objectives: To obtain permeability surface (PS) values using multi-slice helical CT perfusion imaging and to evaluate the spatial distribution correlation between PS values and vascular endothelial growth factor (VEGF) expression in solitary brain metastases. Methods: Imaging was performed on 21 patients, PS values being calculated from the central, border and peripheral parts of tumours. VEGF expression was determined by immunohistochemical staining. Results: Rim enhancement was found in 16 cases, the border of the tumour featuring PS elevation with high VEGF expression in 13 cases. In the 5 cases with nodular enhancement, the border and the central part had high permeability and VEGF expression was high in all cases, the correlation being significant (P<0.01). Conclusion: VEGF expression in brain metastases positively correlates with PS values from CT perfusion imaging, so that the latter can be used in the surveillance of angiogenic activity in brain metastases.

발육성타액선결손의 방사선학적 연구 (A RADIOLOGIC STUDY OF DEVELOPMENTAL SALIVARY GLAND DEFECTS)

  • 최순철;김영걸
    • 치과방사선
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    • 제25권1호
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    • pp.115-125
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    • 1995
  • Forty-four cases of developmental salivary gland defects in 43 patients were analysed radiologically. The obtained results were as follows ; 1. It occurred more frequently in males(86 %) than in females(14 %). The age distribution of patients ranged from 20 to 74 years with the average being 52.7 years. 2. All but one were located between the angle of the mandible and the molar tooth. Only one patient showed bilateral occurrence. 3. The shape of the defect was ovoid(15 cases), round(10 cases), or half-ovoid(5 cases) 4. Their size ranged from 5 x 6 mm to 16 x 30 mm with the average around 9 x 14 mm. 5. Twenty-eight cases appeared to be surrounded partially(1/3 - 2/3) by a hyperostotic border. The thickness of the hyperostotic border varied ; thick(14 cases), moderate(l1 cases), thin(9 cases), or mixed(6 cases) 6. Thirteen cases were in contact with the superior border of the mandibular inferior cortex, 11 cases partially eroded the cortical plate, and 7 cases showed discontinuity of the mandibular inferior cortex. 7. Twenty-three cases were located below the mandibular canal, 13 cases overlapped the mandibular canal, and 2 cases showed slight deviation of the mandibular canal.

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Effects of Ethanol on $Na^+-dependent$ Solute Uptake in Rabbit Renal Brush-Border Membrane Vesicles

  • Kim, Yong-Keun;Ko, Sun-Hee;Woo, Jae-Suk;Jung, Jin-Sup;Lee, Sang-Ho
    • The Korean Journal of Physiology and Pharmacology
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    • 제3권2호
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    • pp.191-198
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    • 1999
  • This study was undertaken to examine the effect of ethanol on $Na^+-dependent$ transport systems (glucose, phosphate, and dicarboxylate) in renal brush-border membrane vesicles (BBMV). Ethanol inhibited $Na^+-dependent$ uptakes of glucose, phosphate, and succinate in a dose-dependent manner, but not the uptakes of $Na^+-dependent.$ The $H^+/TEA$ antiport was reduced by 8% ethanol. Kinetic analysis showed that ethanol caused a decrease in $V_{max}$ of three transport systems, leaving $K_m$ values unchanged. Ethanol decreased phlorizin binding, which was closely correlated with the decrease in $V_{max}$ of $Na^+-glucose$ uptake. These results indicate that ethanol inhibits $Na^+-dependent$ uptakes of glucose, phosphate, and dicaboxylate and that the reduction in $V_{max}$ of $Na^+-glucose$ uptake is caused by a decrease in the number of active carrier proteins in the membrane.

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