1.Immunohistochemical Study on Cytokeratin Expression in Tracheal Epithelium of Human Fetus.
Kwang Soo OH ; Kwang Il NAM ; Sung Sik PARK ; Sung Sik PARK
Korean Journal of Physical Anthropology 1996;9(1):55-67
Trachea is lined by a pseudostratified epithelium which usually expresses a complex mixture of stratified as well as simple epithelial-type cytokeratins. In the present work, the cytokeratin expressions was studied immunohistochemically in the tracheal epithelium and gland of human fetus at 14, 26 and 32 weeks of gestation. The primary antibodies used were CK7, 8, 10, 14, 18, AE8, 5D3, MNFl16 and AE3. In PAS-hematoxylin stain, the tracheal eithelium was composed of pseudostratified ciliated columnar type and consisted of surface, intermediate and basal layers regardless of gestational ages. The PAS positive cells, however, were decreased in number in proportion to gestational ages. The tracheal gland was not fully differentiated at 14 weeks of gestation, and had well differentiated secretory portions consisting mucous and serous cells at 26 and 32 weeks of gestation. The mucous cells and luminal border of the duct were positive for PAS stain. The tracheal eithelium showed different immunoreactivity between cartilageous and membranous portions. In general, CK7 and 5D3 were expressed in surface cells, AE8 in intermediate cells, and MNFl16 and AE3 in the cells of all layers. At 14 weeks of gestation, the tracheal epithelium immunoreacted for CK7, AE8, 5D3, MNFl16 and AE3. The premordium of tracheal gland was positive for 5D3, MNFl16 and AE3. The tracheal epithelium at 26 and 32 weeks of gestation showed same staining properties to those at 14 weeks of gestation. The duct cells at 26 weeks of gestation were immunoreactive for CK7, 8, 14, 18, AE8, 5D3, MNFl16 and AE3, and those at 32 weeks of gestation were immunoreactive for CK7, 14, 5D3, MNFl16 and AE3. The acinar cells at 26 and 32 weeks of gestation were positively stained for CK7, 8, 18, 5D3, MNFl16 and AE3. These results suggest that CK7 and 5D3 may serve as useful markers for mature cilated cells, AE8 (CKl3) for immature ciliated cells, and CKl4 for duct cells in tracheal epithelium and gland.
Acinar Cells
;
Antibodies
;
Epithelium*
;
Fetus*
;
Gestational Age
;
Humans*
;
Immunohistochemistry
;
Keratins*
;
Phenobarbital
;
Pregnancy
;
Trachea
3.Two cases of tick bites caused by ixodes nipponensis.
Nam Joon CHO ; Dong Sik BANG ; Baik Kee CHO ; Young Jin OH ; Won Koo LEE
Korean Journal of Dermatology 1991;29(4):533-537
No abstract available.
Ixodes*
;
Tick Bites*
;
Ticks*
4.Electron microscopic study on the brain capillary and pericapillary structures of the head-irradiated rats.
E Tay AHN ; Choong Nam OH ; Nam Gil YANG ; Jeong Sik KO ; Kyung Ho PARK ; Jin Gook KIM
Korean Journal of Anatomy 1993;26(3):311-325
No abstract available.
Animals
;
Brain*
;
Capillaries*
;
Rats*
5.EFFECT OF TIME AND TEMPERATURE ON THE MARGINAL FIT OF PROVISIONAL RESIN CROWN DURING POLYMERIZATION.
Seung Hwan YOUN ; Nam Sik OH ; Il Kyu KIM ; Sung Seop OH ; Jin Ho CHOI ; Wang Sik KIM ; Young Il RIM
The Journal of Korean Academy of Prosthodontics 2001;39(5):514-525
The purpose of this study was to compare the marginal fit of provisional restorations by differentiating the removal time and setting temperature during resin polymerization. After mixing autopolymerizing methyl metharcrylate resin, the material was placed in a preformed resin shell crown. The crown was seated on a die with 1mm shoulder margin. Crowns were removed after 3,4,5,6 minutes and polymerization was continued under the following conditions : 25degrees C air,30degrees C, 40degrees C, 50degrees C,60degrees C,70degrees C water. After polymerization, the crown was sectioned. The marginal & occlusal discrepancies were measured. The mean marginal discrelpancies at 3 minutes, 4 minutes, 5 minutes and 6 minutes of removing time were 96.6micrometer,84.6micrometer, 86.7micrometer and 105.6micrometer.The mean occlusal discrepancies at 3 minutes, 4 minutes, 5 minutes and 6 minutes of removing time were 106.7micrometer, 89.3micrometer, 98.6micrometer and 127.7micrometer.There was significant difference between 4 minutes group and 6 minutes group in occlusal discrepancies. The mean marginal & occlusal discrepancies for crowns polymerized in 25degrees C air were 98.2micrometer and 124.1micrometer. The crowns polymerized in 50degrees C water demonstrated the smallest marginal & occlusal discrepancies. The mean value of marginal & occlusal discrepancies in 50degrees C water were 73.1micrometer and 77.5micrometer. These values were smaller than that of 25degrees C air.There were significant differences in the occlusal discrepancies between 25degrees C air and water conditions of 50degrees C water (alpha=0.05) but, no significant differences in marginal discrepancies. There was no significant difference in the interaction between time and temperature. 4 minutes waiting time & 50degrees C water polymerizing condition produces the best fit at the margin of the provisional crown.
Crowns*
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Polymerization*
;
Polymers*
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Shoulder
;
Water
6.The optimal design of connectors in all ceramic fixed partial dentures manufactured from alumina tape.
Nam Sik OH ; Han Sung KIM ; Myung Hyun LEE ; Keun Woo LEE
The Journal of Korean Academy of Prosthodontics 2004;42(2):125-132
STATEMENTS OF PROBLEM: All ceramic fixed partial denture cores can be made by the slip casting method and the advanced alumina tape method. The fracture resistance of these core connector areas is relatively low. PURPOSE: The purpose of this study is to standardize the appropriate volumetric figure and location of the connectors in the alumina core fabricated in alumina tape to be used in fixed partial dentures by way of topology optimization. MATERIAL AND METHOD: A maxillary anterior three-unit bridge alumina core with teeth form and surrounding periodontal apparatus model was used to ultimately design the most structurally rigid form of the connector. Loadings from a 0 degree, 45 degrees and 60 degrees to the axis of each tooth were applied and analyzed with the 3-D finite element analysis method. Using the results from these experiments, the topology optimization was applied and the optimal reinforcement layout of connector was obtained and the detail shape in the fixed partial denture core was designed. RESULTS: The modified prosthesis with the form of a bulk in the lower lingual surface of the connector in the event, reduced the stress concentration up to 20% in the 3-D FEA. CONCLUSION: The formation of a bulk in the lower lingual connector area of an alumina core for a fixed partial denture decreases the stress to a clinically favorable measure but does not harm the esthetic point of view. This result illustrates the possibility of clinical application of the modified form designed by the topology optimization method.
Aluminum Oxide*
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Axis, Cervical Vertebra
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Ceramics*
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Denture, Partial, Fixed*
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Finite Element Analysis
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Prostheses and Implants
;
Tooth
7.Two cases of Goldenhar syndrome.
Moo Young SONG ; Min Sik KIM ; Nam Soo PARK ; Un Jun HYOUNG ; Jin Oh LEE ; Eun Ryoung KIM
Journal of the Korean Pediatric Society 1991;34(5):730-735
No abstract available.
Goldenhar Syndrome*
8.Rupture of the Extensor Pollicis Longus Tendon at the Proximal Screw of Volar Plate Fixation for Distal Radius Fracture: A Case Report.
Dong Ju SHIN ; Seung Oh NAM ; Hun Sik CHO
Journal of the Korean Fracture Society 2013;26(4):338-342
As volar plate fixation of distal radius fracture becomes more common, reports of ruptured extensor pollicis longus tendon by a protruding distal screw tip are also increasing steadily. Authors have experienced a rare case of ruptured extensor pollicis longus tendon at the prominent proximal screw of fixed volar plate for distal radius fracture, and we report it herein with a review of the literature.
Radius Fractures
;
Radius
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Rupture
;
Tendons
;
Palmar Plate*
9.The problems of rural interhospital transfer of injured patients to a referal emergency center.
Kyoung Soo LIM ; Young Sik KIM ; Moo Eob AHN ; Sung Oh HWANG ; Nam Cheon CHO ; Sung Joon KANG
Journal of the Korean Society of Emergency Medicine 1992;3(1):44-53
No abstract available.
Emergencies*
;
Humans
10.COMPARISON OF SHEAR BOND STRENGTH AND MARGINAL LEAKAGE OF RESIN MODIFIED GLASS IONOMER CEMENTS.
Hye Yang PARK ; Nam Sik OH ; Keun Woo LEE ; Ho Yong LEE
The Journal of Korean Academy of Prosthodontics 1997;35(4):647-661
The resin modified glass ionomer cements(RMGICs) have been used for years since 1989. Recently it has been developed for luting of fixed restorations. To evaluate the bond strength and marginal leakage of RMGICs for luting usage, the 80 extracted human molars which had uniform area of exposed dentin were cemented with 3 types of RMGICs(Fuji Duet, Advance, Vitremer), a conventional Glass Ionomer Cement(GIC-Fuji I), and a resin cement (Panavia 21) to base metal alloy(Ni-Cr-Be). After thermocycling the specimens were immersed in basic fuschin dye for measuring marginal leakage. The shear bond strength was measured with Instron and the maximum dye penetration was measured to 0.1mm. The type of fractured patterns were determined with stereoscope (x7.5). The results are as follows. 1. The difference between 3 RMGICs and a conventional GIC in shear bond strength was not statistically significant. It seemed that RMGICs had lower shear bond strength than resin cement. (p<0.01) 2. The mean scores of marginal leakage had no significant difference between the resin cement and 3 RMGICs but it was much higher in conventional GIC than the RMGICs (p<0.05) 3. It was determined that the manufacturer and the methods of dentin pretreatment determined the pattern of fracture surface and the frequency of adhesive failure between teeth and 3 RMGICs standed as in following order - Vitremer, Advance, Fuji Duet. (p<0.01) When the fracture pattern was analyzed, it could be said that the materials and the method of dentin pretreatment have much effect on bonding states. This means that the dentin bonding agents should be improved. But the limited products in this experiment can not evaluate the physical properties of the entire RMGICs. Therefore a further study which can evaluate various RMGICs should be in progress to develop better cements.
Adhesives
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Dentin
;
Dentin-Bonding Agents
;
Glass Ionomer Cements*
;
Glass*
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Humans
;
Molar
;
Resin Cements
;
Tooth