• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.372-380
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• 1999

The purpose of this study was to investigate the distribution of calcitonin gene-related peptide(CGRP) containing nerve fivers after pulp exposure in rats. The Spague-Dawley rats weighing about 250 - 300g were used. The animals were devided into normal control group and experimental groups. Experimental animals were sacrified on 2, 4, 7, 10 days after pulp exposure. The maxillary teeth and alveolar bone were removed and immersed in the 4% paraformaldehyde plus 0.1M phosphate buffer (pH 7.4). Serial frozen $50{\mu}m$ thick sections were cut with a cryostat. In the immunohistochemical staining procedure, the rabbit CGRP antibody was used as a primary antibody. The sections were incubated for 48 hours at $4^{\circ}C$, and placed into biotinylated anti-rabbit IgG as a secondary antibody and incubated in ABC (avidin-biotin complex), The sections were visualized by 0.05% 3.3 diaminobenzidine tetrahydrochloride. The results of this study were as follows: 1. In control group, CGRP containing nerve fibers ran parallel to the long axis of root and reached the coronal pulp. They were distributed on Raschkow plexus under the odontoblastic layer. 2. In 2 day group after pulp exposure, tissue necrosis and acute inflammation occurred and CGRP containing nerve fibers increased. In 4 day group, the necrotic tissue extended to the pulp and CGRP containing nerve fibers were distributed around the inflammation zone. 3. In 7 day group after pulp exposure, pulp necrosis occurred, and in 10 day group, the abscess under the necrotic pulp extended to the root apex area and CGRP containing nerve fibers were not observed in root canals. 4.The sprouting of CGRP nerve fibers was most remarkable at the pulp chamber under injury in 4 day group, and it was found at inflammation zone under the necrotic tissue in 7 day group and the remaining root pulp tissue in 10 day group. As mentioned above, CGRP nerve fibers had a tendency to increase around the inflammatory zone, especially around the acute inflammation tissue, when compared with control group. It is suggested that CGRP nerve fibers maybe related to the control of inflammatory response of pulp tissue.

• Journal of Chest Surgery
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• v.54 no.6
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• pp.551-553
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• 2021

Although it is attractive, a limitation of aortic valve (AV) replacement (AVR) through a mini-thoracotomy approach (mini-AVR) is the limited exposure of the AV. Here, we present a simple exposure technique named "suspending commissural sutures" for a more efficient mini-AVR. The technique involves making 3 half-depth stitches with 1-0 silk at each of the commissures, which are anchored to each corresponding pericardial surface. These stitches are tightened up so that the aortic root is axially expanded and is pulled upward. The technique of suspending commissural stitches seems to offer reasonable exposure of the AV in mini-AVR, and shows excellent early surgical outcomes.

• The Korean Journal of Applied Statistics
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• v.24 no.2
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• pp.279-292
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• 2011

Credibility theory is one of the most important theories of actuarial science to calculate the proper insurance premium. In this paper, the rule of relative exposure volume, the square root rule, the B$\"{u}$hlmann credibility and B$\"{u}$hlmann-Straub credibility with the basic concept of credibility have been introduced, Also, we estimate new premiums based on these methods for real data. As a result, the rule of relative exposure volume provides the highest accuracy.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.538-548
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• 1995

Calcium hydroxide has been used not only as pulp capping and pulpotomy agents in the operative dentistry, but dressing and temporary filling materials in root canal treatment. Calcium hydroxide was known to stimulate odontoblast to produce new reparative dentin and to eliminate microorganims effectively in the infected root canals. The purpose of this study was to evaluate the effect of calcium hydroxide solution on cultured L929 cells and its antibacterial effect on several streptococci. Calcium hydroxide solution (0.121g/100ml) was added to L929 cells and cell viability was measured using 3-(4,5-dimethylthiazol-2-yl) -2,5-dimethyltetrazolium bromide (MTT) and neutral red (NR) dye. Calcium hydroxide solution (20, 40, 60, 80, 100 and $150{\mu}l$) was added to L929 cells in 96-well microplates for 1, 4 and 24 hours respectively. Cell viability was gradually decreased when the volume and exposure time of calcium hydroxide solution were increased. When $150{\mu}l$ of calcium hydroxide was applied to L929 cells for 24 hours, there was more than fifty percent reduction of cell viability. Calcium hydroxide solution (20g/100ml) showed antibacterial effect against S. uberis, S. intermedius and S. mitis after thirty-second exposure. But 0.121g/100ml concentration of cacium hydroxide solution exhibited no antibacterial effect on six streptococci after one-hour exposure.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.26-32
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• 1998

Three major trails of campus forest in Chungnam National University were selected to investigate the use impacts on environmental deterioration of trail according to the different amount of use. Rook-exposed, root-exposed, deepening, widening, diverged points as the deterioration types of trail which were surveyed at total of 92 points in major trail of campus forest in Chungnam National University. Major deterioration types of trail were widening, rock-exposure, root-exposure, in order of frequency. And trail conditions (trail slope and maximum depth) of deteriorated points were significantly different from those of non-deteriorated points.

• Imaging Science in Dentistry
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• v.47 no.3
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• pp.189-197
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• 2017

Purpose: To quantify artifacts from different root filling materials in cone-beam computed tomography (CBCT) images acquired using different exposure parameters. Materials and Methods: Fifteen single-rooted teeth were scanned using 8 different exposure protocols with 3 different filling materials and once without filling material as a control group. Artifact quantification was performed by a trained observer who made measurements in the central axial slice of all acquired images in a fixed region of interest using ImageJ. Hyperdense artifacts, hypodense artifacts, and the remaining tooth area were identified, and the percentages of hyperdense and hypodense artifacts, remaining tooth area, and tooth area affected by the artifacts were calculated. Artifacts were analyzed qualitatively by 2 observers using the following scores: absence (0), moderate presence (1), and high presence (2) for hypodense halos, hypodense lines, and hyperdense lines. Two-way ANOVA and the post-hoc Tukey test were used for quantitative and qualitative artifact analysis. The Dunnet test was also used for qualitative analysis. The significance level was set at P<.05. Results: There were no significant interactions among the exposure parameters in the quantitative or qualitative analysis. Significant differences were observed among the studied filling materials in all quantitative analyses. In the qualitative analyses, all materials differed from the control group in terms of hypodense and hyperdense lines (P<.05). Fiberglass posts did not differ statistically from the control group in terms of hypodense halos(P>.05). Conclusion: Different exposure parameters did not affect the objective or subjective observations of artifacts in CBCT images; however, the filling materials used in endodontic restorations did affect both types of assessments.

• Journal of Sericultural and Entomological Science
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• v.32 no.1
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• pp.1-4
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• 1990

The resistance against drying of mulberry (Morus alba L.) graftages lifted in the fall and spring was examined by measuring water loss, survival, and regrowth. The graftages were exposed on the ground an4 covered with 2 sheets of straw mat for 0, 1, 3, 6, 10, and 15 days. 1. Temperatures in the mat ranged from 13 to -6.5$^{\circ}C$ in fall and 24 to -2.8$^{\circ}C$ in spring. Relative humidity was 37 to 100% in fall and 20 to 100% in spring. 2. Water loss from the graftages was less than 10% after 10 days exposure in fall, whereas there was 9.8% loss with 1 day exposure in spring. 3. Six days exposure in the spring caused the root hairs to dry and the root surface to become wrinkled longitudinally and turn yellowish-red. 4. Maximum exposure which allowed 100% survival and regrowth after planting was 6 days in fall and 3 days in spring under 2 sheets of straw mat.

• Journal of Korean Neurosurgical Society
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• v.55 no.1
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• pp.64-65
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• 2014

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.76-86
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• 2018

Turfgrass species were evaluated for their rooting and foliar characteristics, and their interaction with the soil. The rooting system was divided into three compartments, one above another, such that the top and bottom compartments of the root system could be supplied with a nutrient deprived solution. Exposure of parts of the roots to nitrate deprivation caused a localised retardation of root initiation and extension, compared with zones receiving the full supply of nutrients. This resulted in considerable modification to root form, coupled with a significant depression in foliar growth. The extension of roots was the least affected by the deprivation of potassium. Phosphate and calcium deprivations gave rise to similar responses in root and foliar formation. Results from this study showed that external concentrations of nitrogen, phosphorus, potassium and calcium are required by the root system in varying amounts for optimal growth of roots. Turfgrass coverage and turf quality ratings further reinforced these findings. No significant difference was observed between the different grasses examined here. All three species responded similarly to the deprivation of the various nutrients. Results from this study confirmed that targeted fertilization programs are beneficial and can help reduce cost, chemical usage and prevent leachate and contamination.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.782-791
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• 1997

Glial fibrillary acidic protein(GFAP) are a group of intermediate filaments that are distributed in the cytoplasm of many type of glial cells. The purpose of this study was to determine change of GFAP immunoreactivity(GFAP-IR) in rat trigeminal ganglion satellite cells in response to pulp exposure. The immunohistochemistry was carried out using the avidinbiotin-peroxidase complex(ABC) method and subsequently stained with AEC(3-aminoethyl-9-carbasol). 1. Contol group; Central root astrocytes had strong GFAP-IR, but ganglion satellite cells occasionlly had GFAP-IR. This reaction patterns of ganglion satellite cells was not concenturated in any specific region of trigeminal ganglion. 2. Three day pulp exposure group; There was a highly GFAP-IR in satellite cells of trigeminal ganglion in maxillary region. GFAP-IR in neighboring mandibular and ophthalmic regions was less intense compared to maxillary region. 3. Seven day pulp exposure group; In this group, GFAP-IR that was increased compared to control group was seen in the maxillary region. But GFAP-IR was less intense compared to three day pulp exposure group. These results suggest that GFAP in satellite cell increase in specific region of trigeminal ganglion after pulp exposure and offer useful tool in trigeminal pain research.