• Tuberculosis and Respiratory Diseases
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• v.64 no.4
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• pp.259-265
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• 2008

Background: Patients with diabetes mellitus are highly sensitive to infections, including tuberculosis, and the longer the duration of DM, the greater is the prevalance of tuberculosis. We studied the difference of the clinical manifestations, radiologic findings, resistance and others factors of patients with diabetic and non-diabetic pulmonary tuberculosis. Methods: The patients we enrolled in this study were newly diagnosed with pulmonary tuberculosis from January 2003 to December 2005. Results: 159 patients were enrolled in this study. There were 30 pulmonary tuberculosis patients with diabetic mellitus (DMTB) and 129 pulmonary tuberculosis patients without diabetic mellitus (non-DMTB). There was no difference in the basic characteristics and clinical manifestation between both the groups. For the chest X-ray findings, the moderately advanced tuberculosis patients were the most common (43.3% in the DMTB group and 49.6% in the non-DMTB group). There was no relation between the severity of tuberculosis activity on chest x-ray and the presence of diabetes. The prevalence of cavitory lesions in the DMTB group was significantly higher than that in the non-DMTB group, but the prevalence of atelectasis was higher in the non-DMTB group (p<0.05). There was no difference in the incidence of lower lung involvement, the number of involved lobes, the number of treatment days and the radiological sequelae in both groups. Conclusion: The DMTB patients had a higher incidence of cavitory lesions and a higher incidence of atelectasis than the non-DMTB patients.

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.147-158
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• 2004

Laboratory dynamic tests are carried out to assess the liquefaction potential of saturated sands in most countries. However, simple results such as the maximum cyclic shear stress and the number of cycles at initial liquefaction are used in the experimental assessment of liquefaction potential, even though various results can be obtained from the dynamic test. In addition, it seemed to be inefficient because more than three dynamic tests with different stress ratio have to be carried out to draw a liquefaction resistance experimental curve. To improve the present assessment method fur liquefaction potential, a new critical resistible characteristic far soil liquefaction is proposed and verified through conventional cyclic triaxial tests with Jumunjin sand. In the proposed method, various experimental data such as effective stress path, stress-strain relationship, and the change of excess pore water pressure can be used in the determination of cumulative plastic shear strains at every 1/4 cycle. Especially, the critical cumulative plastic shear strain to initiate liquefaction can be defined in a specific point called a phase change point in the effective stress path and it can be calculated from a hysteric curve of stress-strain relationship up to this point. Through this research, it is found that the proposed cumulative plastic shear strain can express the dissipated energy to resist dynamic loads and consider the realistic soil dynamic behavior of saturated sands reasonably. It is also found that the critical plastic shear strain can be used as a registible index of soils to represent the critical soil dynamic state, because it seems to include no effect of large deformation.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.1
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• pp.1-11
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• 2008

Statement of problem: Over the past decade, increased demand for esthetically pleasing restorations has led to the development of all-ceramic systems. Recent reports suggest that the all-ceramic crowns have excellent physical properties, wear resistance, and color stability. In addition, numerous ceramics have excellent biocompatibility, a natural appearance, and improved physical bonding with resin composite luting agents. However, the brittle nature of ceramics has been a major factor in their restriction for universal usage. Functional occlusal loading can generate stress in the luting agent, and the stress distribution may be affected by the marginal geometry at the finish line. Tooth preparation for fixed prosthodontics requires a decision regarding the marginal configuration. The design dictates the shape and bulk of the all ceramic crowns and influences the fit at the margin. Purpose: The purpose of this study was to evaluate the stress distribution within marginal configurations of all- ceramic crowns (90-degree shoulder, 110-degree shoulder, 135-degree shoulder). Material and methods: The force is applied from a direction of 45 degrees to the vertical tooth axis. Three-dimensional finite element analysis was selected to determine stress levels and distributions. Results and conclusion: The result of stress level for the shoulder marginal configuration was more effective on stress distribution at 135-degree shoulder margin. But the stresses concentrated around at 135-degree shoulder margin. The stress decreased apically at the surface between cements and alumina core, and increased apically at the surface between alumina core and veneering porcelain.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.3
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• pp.746-763
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• 1996

An alternative design to conventional class II cavity preparation for proximal carious lesions is the tunnel preparation. It preserves the marginal ridge intact, thus making it possible to maintain the natural contact relationship with the adjacent tooth and minimize tooth reduction. This in vitro study was purposed to evaluate the effect of the materials' elastic constants and shear-bond strength on the marginal ridge fracture resistance of teeth restored by the tunnel technique, and to find the materials of choice for tunnel restorations. $Resinomer^{(R)}$, $Ketac-silver^{(R)}$, $Miracle-Mix^{(R)}$, and Tytin were used as restorative material. The elastic constants of each restorative material were evaluated by ultrasonic pulse measurement. Young's modulus and bulk modulus of the restorative materials were evaluated in three specimens for each material type. The shear-bond strength of the restorative materials to the dentin surface was measured after thermocycling 400 times between 6 and $60^{\circ}C$, using ten specimens for each material type. For measuring marginal ridge strength, 60 sound extracted molar teeth were distributed into six groups by size. Sound molar teeth were used as a Control group and unfilled prepared teeth were grouped as Unrestored. Another four groups were named Resinomer group, Ketac-Silver group, Miracle Mix group, and Tytin group by type of restorative material. Tunnel cavity preparation was done with ' 1/2, 2, and 4 round burs in sequence. Initial access to proximal surface was made through an occlusal access preparation started at least 2mm from the marginal ridge, and the proximal opening was formed about 2.5mm below the marginal ridge. After restoration and thermocycling, marginal ridge strength was measured using a universal testing machine. The results were as follows: 1. The Young's modulus of $Tytin^{(R)}$ was 63.95 GPa, followed by $Ketac-Silver^{(R)}$ 27.60 GPa, $Miracle-mix^{(R)}$ 18.48 GPa, and $Resinomer^{(R)}$ 10.74 GPa showing significant differences between the groups(P<0.05). The bulk modulus of the materials showed the same order as Young's modulus. The value of $Tytin^{(R)}$ showed 59.57 GPa indicating that it will deform less than other materials under the same stress. It was followed by $Ketac-Silver^{(R)}$ 23.57 GPa, Miracle $Mix^{(R)}$ 12.50 GPa, and $Resinomer^{(R)}$ 11.60 GPa. 2. The Resinomer group had a shear-bond strength of 7.41 MPa which was significantly higher than those of the Ketac-Silver group (1.80 MPa) and the Miracle Mix group (2.84 MPa) (P<0.01). All the specimens of Tytin group detatched from the dentin surface during thermocycling. 3. The mean marginal ridge strength of the Unrestored group(46.14 kgf) was significantly lower than that of the Control group (84.24 kgf) (P<0.01). The marginal ridge strength of teeth restored by the tunnel technique was, in order, Ketac-Silver group 74.06 kgf, Miracle Mix group 73.36 kgf, Resinomer group 63.47 kgf, and Tytin group 58.76 kgf. The Ketac-Silver, Miracle Mix, and Resinomer groups showed no significant difference with the Control group (P>0.05), but the Tytin group showed significantly lower strength compared to the Control group(P<0.05). The results showed that the marginal ridge strength of the teeth restored by the tunnel technique was not significantly lower than that of sound teeth. They also demonstrated that the bonding strength of the restorative material to the tooth surface should be high and the modulus of elasticity should not be lower than that of the tooth in order to restore the marginal ridge strength to its natural condition.

• Neonatal Medicine
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• v.18 no.1
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• pp.49-58
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• 2011

Purpose: The purpose of this study was to evaluate the relationship between cord blood adiponectin and insulin-like growth factor (IGF)-I and their effect on fetal growth and insulin resistance in mothers with gestational diabetes mellitus (GDM). Methods: Cord blood adiponectin and IGF-I were compared between mothers with GDM (GDM group, N=53) and controls (non-GDM group, N=101). Neonates were classified into three groups of small for gestational age (SGA, N=26), appropriate for gestational age (AGA, N=97), and large for gestational age (LGA, N=31) by birth weight. The association between cord adiponectin and IGF-I levels was evaluated in relation to maternal and neonatal clinical data. Results: Cord adiponectin was lower in the GDM group than in the non-GDM group (P<0.001). There was no significant difference in cord adiponectin among the SGA, AGA, and LGA groups in the GDM group (P=0.228). The cord adiponectin of AGA in the GDM group was significantly lower than that in the non-GDM group (P<0.001). The most powerful predictor affecting cord adiponectin was the result of maternal 75 g oral glucose tolerance test. The cord IGF-I values between the GDM group and the non-GDM group were not different (P=0.834). Neonates with the heavier birth weight had the higher cord IGF-I levels. The most powerful predictor affecting cord IGF-I was birth weight and the next was maternal parity. Conclusion: Both cord blood adiponectin and IGF-I were associated with fetal growth, but IGF-I was a more general and direct factor affecting fetal body size, and adiponectin seemed to have more association with insulin sensitivity than growth.

• The korean journal of orthodontics
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• v.41 no.6
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• pp.399-410
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• 2011

Objective: The purpose of this study was to evaluate the difference in frictional resistance among metal, ceramic, self-ligation brackets and coated or non-coated Ni-Ti archwires at various bracket-archwire angulations during the sliding movement of an orthodontic archwire, using an orthodontic sliding simulation device. Methods: Four types of bracket (Micro-arch Perpect Clear2 Clippy-C and Damon3 and 5 types of orthodontic archwire (0.014", 0.016", and 0.016" ${\times}$ 0.022" inch coated Ni-Ti, and 0.016" and 0.016" ${\times}$ 0.022" inch Ni-Ti) were used. Further, the bracket- archwire angles were set at 4 different angulations: $0^{\circ}$, $3^{\circ}$, $6^{\circ}$, and $9^{\circ}$. Results: The frictions from all the experimental groups were found to be significantly increased in order of self-ligation brackets, Micro-arch and Perpect Clear2 ($p$ < 0.001). The presence of a coat had no effect on the friction of the same sized archwires at $0^{\circ}$ and $3^{\circ}$ bracket-archwire angles ($p$ < 0.001). Coated archwires had significantly higher frictions than the same sized non-coated archwires at $6^{\circ}$ and $9^{\circ}$ bracket-archwire angles ($p$ < 0.001). The frictions increased significantly as the bracket-archwire angles were increased ($p$ < 0.001). Conclusions: The use of self-ligation brackets will be beneficial in clinical situations where a low frictional force is required. Further, in cases where crowding is not severe, the use of coated archwires should not cause problems. However, more additional explanation is required considering the fact that the damage of coated archwire and exposure of the metal portion in case of binding and notching and the effects of saliva were not taken into account.

• Journal of Wetlands Research
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• v.22 no.3
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• pp.194-199
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• 2020

Unlike in the past, the world is facing water shortages due to climate change and difficulties in simultaneously managing the risks of flooding. The Four Major Rivers project was carried out with the aim of realizing a powerful nation of water by managing water resources and fostering the water industry, and the construction period was relatively short compared to the unprecedented scale. Therefore, the prediction and analysis of how the river environment changes after the Four Major Rivers Project is insufficient. Currently, part of the construction section of the Four Major Rivers Project is caused by repeated erosion and sedimentation due to the effects of sandification caused by large dredging and flood-time reservoirs, and the head erosion of the tributaries occurs. In order to solve these problems, the riverbed maintenance work was installed, but it resulted in erosion of both sides of the river and the development of new approaches and techniques to keep the river bed stable, such as erosion and excessive sedimentation, is required. The water agent plays a role of securing a certain depth of water for the main stream by concentrating the flow so much in the center and preventing levee erosion by controlling the flow direction and flow velocity. In addition, Groyne products provide various ecological environments by forming a natural form of riverbeds by inducing local erosion and deposition in addition to the protection functions of the river bank and embankment. Therefore, after reviewing the method of determining the shape of the Groyne structure currently in use by utilizing the mobile limit flow rate and marginal reflux force, a new Critical Movement Velocity(${\bar{U}}_d$) and a new resistance coefficient formula considering the mathematical factors applicable to the actual domestic stream were developed and the measures applicable to Groyne installation were proposed.

• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.51-57
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• 1983

Properties and glue shear strength of each water soluble rues-phenol copolymer adhesive and phenolic resin adhesive were examined as a high temperature curing binder through the manufacture of plywood made of Kapur veneer. The former has different molar ratio and the latter was made from different catalyst method. The results are summarized as follows: 1) Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.67 to 0.82 and their moisture contents met the K.S. standard 2) In dry and wet shear strength, adhesives with 60 percent of non volatile content showed higher values than those with 50 percent except phenolic resin. Urea-phenol copolymer resin with 20 percent of phenol content exhibited the highest, and that with 70 percent the lowest. Filling effect of wood flour on the bonding strength is great in urea-phenol copolymer resin with more than 50 percent of phenol content, especially significant in 50 percent of non volatile content including alkali catalyst phenolic resin. Alkali and acid catalyst methods were the highest among the adhesive manufacture methods. In wet strength, urea resin belongs to the lowest group. 3) In glue shear strength after boiling and drying test, no method for manufacturing phenolic formaldehyde resin adhesive was stronger than alkali and acid catalyst methods. Phenolic resin made from alkali catalyst method needs a wood flour filler to improve the bonding quality. Urea-phenol copolymer resin with 10 percent of phenol content showed the reasonable water resistance.

• Journal of Yeungnam Medical Science
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• v.25 no.1
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• pp.31-40
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• 2008

Background/Aims : Entecavir is a synthetic nucleoside analogue, cyclopentyl guanine nucleoside, which has a potent antiviral effect and the least viral breakthrough in hepatitis B virus (HBV) replication. Entecavir has been available in Korea since 2007 but there are few reports on its effects. The aim of this study was to evaluate the virological response (VR) and biochemical response (BR) to entecavir in HBV patients at 3, 6 and 9 months after treatment with entecavir. Materials and Methods : Thirty-three chronic hepatitis B patients who took entecavir for at least 9 months were enrolled. We investigated VR and BR by retrospectively reviewing medical records. Patients who satisfied the following criteria were chosen: 1) initial alanine aminotransferase (ALT) levels = 1.5upper limit of normal (ULN) and 2) initial HBV DNA levels = $5\;log_{10}\;copies/ml$. We measured ALT levels every 3 months until month 9. HBV DNA was measured every 2 or 3 months by polymerase chain reaction (PCR) method. Results : Most patients taking entecavir showed good BR (ALT < 40 IU/L). The BR rates were 61%, 73% and 67% at months 3, 6 and 9, respectively. VR (HBV DNA < $5\;log_{10}\;copies/ml$ or 2 log lower than initial HBV DNA) rates were 82%, 91% and 91% at months 3, 6 and 9, respectively. Undetectable HBV DNA (HBV DNA < 4 log10 copies/ml) rates were 49%, 73% and 85% at months 3, 6 and 9, respectively. Two patients presented with virological breakthrough without adverse effects until month 9. Conclusions : Entecavir showed good BR and VR from month 3 and these effects continued through the 9-month observation period. This suggests that entecavir is also a good choice for the first line treatment of chronic hepatitis B (CHB). Further studies are needed to determine the long-term efficacy and drug resistance of entecavir in Korean CHB patients.

• Radiation Oncology Journal
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• v.17 no.2
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• pp.151-157
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• 1999

Purpose : By sequencing the Erpressed Sequence Tags of human 걸ermal papilla CDNA library, we identified a clone named K872 of which the expression decreased during differentiation of HL6O cell line. Materials and Methods : K872 plasmid DNA was isolated according to QIA plasmid extraction kit (Qiagen GmbH, Germany). The nucleotide sequencing was performed by Sanger's method with K872 plasmid DNA. The most updated GenBank EMBL necleic acid banks were searched through the internet by using BLAST (Basic Local Alignment Search Tools) program. Nothern bots were performed using RNA isolated from various human tissues and cancer cell lines. The gene expression of the fusion protein was achieved by His-Patch Thiofusicn expression system and the protein product was identified on SDS-PAGE. Results : K872 clone is 1006 nucleotides long, and has a coding region of 675 nucleotides and a 3' non-coding region of 280 nucleotides. The presumed open reading frame starting at the 5' terminus of K872 encodes 226 amino acids, including the initiation methionine residue. The amino acid sequence deduced from the open reading frame of K872 shares $70\%$, identity with that of rat glutathione 5-transferase kappa 1 (rGSTKl). The transcripts were expressed in a variety of human tissues and cancer cells. The levels of transcript were relatively high in those tissues such as heart, skeletal muscle, and peripheral blood leukocyte. It is noteworthy that K872 was found to be abundantly expressed in coloreetal cancer and melanoma cell lines. Conclusion : Homology search result suggests that K872 clone is the human homolog of the rGSTK1 which is known to be involved in the resistance of cytotoxic therapy. We propose that meticulous functional analysis should be followed to confirm that.