• Journal of Life Science
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• v.12 no.1
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• pp.1-8
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• 2002

Antlers from deer species are alternative animal by-products. Due to the oriental trade, the velvet antler industry is rapidly emerging in North America. The unique biological property of antler wish a deciduous natural phenomenon offers the valuable model of biomedical research. Growing antlers showed different structures according to cell populations consisting of mesenchymes, chondroblasts, chondrocytes and osseous tissues from distal to proximal portions of main beam. Their structures were different from two tissues, cartilage and bone, in growing antlers. Zone of maturing ants calcifying chondrocytes referred as upper section was invaded by osteoblasts indicating the occurrence of endochondral ossification. The cartilaginous tissues were gradually replaced by osseous tissues downward. The bony tissues referred as the middle and base sections in this thesis contained spongy bone and cortical bone structure in the difference of the degree of mineralization antral the thickness of cortical bony in adjacent to outer velvet layer. In addition, the endocrinological regulators such as testosterone, prolactin, growth hormones and other growth factors are actively involved in the unique deciduous nature shown in the growth and development of antler.

• Radiation Oncology Journal
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• v.13 no.3
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• pp.277-283
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• 1995

Purpose : This study was performed to measure dose alteration at the air-tissue interface resulting from rebuild-up to the loss of charged particle equilibrium in the tissues around the air-tissue interfaces. Materials and Methods : The 6 and 10-MV photon beam in dual energy linear accelerator were used to measure the surface dose at the air-tissue interface The polystyrene phantom sized $25{\times}25{\times}5\;cm^3$ and a water phantom sized $29{\times}29{\times}48\;cm^3$ which incorporates a parallel-plate ionization chamber in the distal side of air gap were used in this study. The treatment field sizes were $5{\times}5\;cm^2,\;10{\times}10\;cm^2\;and\;20{\times}20\;cm^2$. Air cavity thickness was variable from 10 mm to 50 mm. The observed-expected ratio (OER) was defined as the ratio of dose measured at the distal junction that is air-tissue interface to the dose measured at the same point in a homogeneous phantom. Results : In this experiment, the result of OER was close or slightly over than 1.0 for the large field size but much less (about 0.565) than 1.0 for the small field size in both photon energy. The factors to affect the dose distribution at the air-tissue interface were the field size, the thickness of air cavity. and the photon energy. Conclusion : Thus, the radiation oncologist should take into account dose reduction at the air-tissue interface when planning the head and neck cancer especially pharynx and laryngeal lesions, because the dose can be less nearly $29{\%}$ than predicted value.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.559-564
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• 2009

Purpose: Surgical reconstruction of an ischial soft tissue defect presents a challenging problem owing to a high rate of recurrence, especially paraplegic patients. Although various muscle, musculocutaneous and fasciocuta - neous flaps have been used in the reconstruction of ischial soft tissue defect, it is still debated which type of flaps are the best. We had performed a relatively durable adductor magnus perforator island flap based on the perforators originated from the first medial branch of the profunda femoris artery for coverage of ischial soft tissue defect where was not a region universally reconstructed by perforator flap. Methods: From August 2005 until January 2008, the adductor magnus perforator island flap had been used for resurfacing of the ischial soft tissue defects in a series of 6 patients (4 male and 2 female). Ages ranged from 26 to 67 years (mean, 47.5 years), and follow - up period from 13 to 26 months (mean, 16.7 months). Causes were 4 pressure ulcers, 1 cellulitis and 1 suppurative keratinous cyst. Results: The sizes of these flaps ranged from 12 to 18 cm in length and 7 to 9 cm in width. The flaps survived in all patients. Marginal loss over the distal area of the flap by infection was noted in one patient, which was treated successfully with a subsequent split - thickness skin graft. Average thickness of the flap was 0.94 cm, which was more thicker than other perforator flaps. Long term follow - up showed a good flap durability. Conclusion: In planning a reconstructive option of ischial soft tissue defect, the adductor magnus perforator island flap is a relatively large cutaneous flap with a durable thickness. With proper patient selection, careful vascular dissection and postoperative management, we recommend this flap is a good and suitable option for coverage of the ischial soft tissue defect.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.285-296
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• 2010

This study was implemented among 100 students of C College of Public Health who have healthy permanent dentition in order to measure the morphology and sizes of clinical crowns of permanent maxillary molars. The following are conclusions of this study. 1. The cusp height, crown width, crown thickness of clinical crowns appeared to be bilaterally symmetrical. 2. The strong development of the buccal groove showed to be superior in the right first molar. The appearance rate of the buccal pit was high in the right first molar also. 3. The type 4th cusp appeared as 100% in the left and right first molars, and 78%, 75% in the left and right second molars respectively. 4. The distal lingual cusp(DLC) size were bilaterally symmetrical in the type 4th cusp. 5. As for the distance between two cusp tips, it was large between mesial cusp tips in all of the first and second molars at both sides. 6. Development of the Carabelli's cusp was high in both the left and right first molars. 7. The appearance rate of the oblique ridge was 87.0% in the right first molar, 73.0% in the right second molar, 88.0% in the left first molar, and 73.0% in the left second molar. This is considered to be caused by people who have mild dental crown caries in their first molars. 8. The appearance rate of the mesial marginal ridge tubercle(DMRT) was high in both of the left and right first molars. That of the distal tubercle was 16.0% in the right first molar, 26.0% in the right second molar, 14.0% in the left first molar, and 21% in the left second molar.

• Clinics in Shoulder and Elbow
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• v.15 no.2
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• pp.109-116
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• 2012

Purpose: The aim of this study was to evaluate preoperative ultrasonographic findings and usefulness in ulnar neuropathy around elbow. Materials and Methods: Twenty-two patients with ulnar neuropathy were performed preoperative ultrasonogram. The route, location, thickness of the ulnar nerve and space occupying lesion through longitudinal scan were evaluated. Cross-sectional areas of the ulnar nerve were measured at the level of medial epicondyle and 3 cm proximal and distal to the medial epicondyle through axial scan. Correlations between swelling ratio of ulnar nerve and eletrophysiologic study and preoperative Dellon's assessment were checked. Results: In 21 cases (95.6%) of total 22 cases, diffuse swelling of the ulnar nerve around elbow were identified. 4 cases had space occupying lesions including 3 ganglionic cysts and 1 heterotopic ossification. Cross sectional areas at the level of medial epicondyle were significantly larger than at the level of 3 cm proximal and distal to the medial epicondyle (p<0.05). There were no statistically significant correlations between swelling ratio of ulnar nerve and eletrophysiologic study and preoperative clinical assessment (p>0.05). Conclusion: This study showed that ultrasonography was helpful to detect etiology of ulnar neuropathy around elbow such as space occupying lesion, morphological change or dislocation of ulnar nerve. It could be useful tool for diagnosis and treatment in patients with ulnar neuropathy at elbow.

• Journal of Periodontal and Implant Science
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• v.43 no.4
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• pp.153-159
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• 2013

Purpose: The level of the implant above the marginal bone and flap design have an effect on the bone resorption during the healing period. The aim of this study is to detect the relationship between the level of the implant at the implant placement and the bone level at the healing period in the mesial and distal side of implants placed with flapless (FL) and full-thickness flap (FT) methods. Methods: Twenty-two nonsubmerged implants were placed with the FL and FT technique. Periapical radiographs were taken of the patient at implant placement, and at 6 and 12 weeks. By using computer software, bone level measurements were taken from the shoulder of the healing cap to the first bone implant contact in the mesial and distal side of the implant surface. Results: At 6 weeks, the correlation between the crestal bone level at the implant placement and crestal bone level of the FT mesially was significant (Pearson correlation coefficient=0.675, P<0.023). At 12 weeks, in the FT mesially, the correlation was nonsignificant (Spearman correlation coefficient=0.297, P<0.346). At 6 weeks in the FT distally, the correlation was nonsignificant (Pearson correlation coefficient=0.512, P<0.107). At 12 weeks in the FT distally, the correlation was significant (Spearman correlation coefficient=0.730, P<0.011). At 6 weeks in the FL mesially, the correlation was nonsignificant (Spearman correlation coefficient=0.083, P<0.809). At 12 weeks in the FL mesially, the correlation was nonsignificant (Spearman correlation coefficient= 0.062, P<0.856). At 6 weeks in the FL distally, the correlation was nonsignificant (Spearman correlation coefficient=0.197, P<0.562). At 12 weeks in the FL distally, the correlation was significant (Pearson correlation coefficient=0.692, P<0.018). Conclusions: A larger sample size is recommended to verify the conclusions in this preliminary study. The bone level during the healing period in the FT was more positively correlated with the implant level at implant placement than in the FL.

• Applied Microscopy
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• v.15 no.2
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• pp.111-129
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• 1985

The morphology and histology of the gastrointestinal mucosa of the mole, Talpa micrura coreana (Thomas), were studied using light and scanning electron microscopes. Tissue specimens were taken from body and pyloric portions of the stomach, and from the initial, proximal, middle, distal and terminal portions of the intestine. For light microscopy, tissue blocks were fixed in 10% buffered neutral formalin, embedded in paraffin wax, and sectioned at a thickness of $5{\mu}m$. These sections were stained with hematoxylin-eosin. For scanning electron microscopy, tissue blocks were fixed in 1% glutaraldehyde-1.5% paraformaldehyde, and postfixed in 1% osmium tetroxide, dehydrated in graded alcohol, transferred to isoamylacetate and dried by the critical point drier(Polaron E 3000). Subsequently, specimens were coated with gold and observed with a JSM-35C scanning electron microscope. The results were as follows: The mucous membrane of the body portion of the stomach had numerous irregular folds and the pyloric mucosa formed the strawberry-shaped folds, and general histological structures of each portion were similar to those of man. The intestine could not be differentiated macroscopically and microscopically into small and large intestines. There was no cecum, appendix, taenia coli, haustra coli or appendices epiploicae. In the initial portion (4 mm long), conical or tongue-shaped villi with the height of $143.3{\pm}10.7{\mu}m$ were present, and large mucous glands were seen in the submucosa. In the proximal, middle and distal portions, wavy folds composed of the epithelium and lamina propria were densely and transversely arranged, and their heights were $440.4{\pm}45.5{\mu}m,\;454.4{\pm}19.9{\mu}m\;and\;205.2{\pm}33.5{\mu}m$, respectively. The mucosa of the terminal portion (3 cm long) formed several longitudinal folds, and the intestinal glands were directly opened on the smooth surface of the folds. Aggregated lymphoid follicles were observed in the major portions of the intestine except the initial and terminal portions. There was no circular or semilunar fold throughout the intestine.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.3
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• pp.194-201
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• 2010

Purpose: The purpose was to compare the marginal fidelity and the fracture resistance of the zirconia crowns according to the various coping designs with different thicknesses and cement types. Materials and methods: Zirconia copings were designed and fabricated with various thicknesses using the CAD/CAM system (Everest, KaVo Dental GmbH, Biberach., Germany). Eighty zirconia copings were divided into 4 groups (Group I: even 0.3 mm thickness, Group II: 0.3 mm thickness on the buccal surface and the buccal half of occlusal surface and the 0.6 mm thickness on the lingual surface and the lingual half of occlusal surface, Group III: even 0.6 mm thickness, Group IV: 0.6 mm thickness on the buccal surface and the buccal half of occlusal surface and the 1.0 mm thickness on the lingual surface and the lingual half of occlusal surface) of 20. By using a putty index, zirconia crowns with the same size and contour were fabricated. Each group was divided into two subgroups by type of cement: Cavitec$^{(R)}$ (Kerr Co, USA) and Panavia-$F^{(R)}$ (Kuraray Medical Inc, Japan). After the cementation of the crowns with a static load compressor, the marginal fidelity of the zirconia crowns were measured at margins on the buccal, lingual, mesial and distal surfaces, using a microscope of microhardness tester (Matsuzawa, MXT-70, Japan, ${\times}100$). The fracture resistance of each crown was measured using a universal testing machine (Z020, Zwick, Germany) at a crosshead speed of 1 mm/min. The results were analyzed statistically by the two-way ANOVA and oneway ANOVA and Duncan's multiple range test at $\alpha$=.05. Results: Group I and III showed the smallest marginal fidelity, while group II demonstrated the largest value in Cavitec$^{(R)}$ subgroup (P<.05). For fracture resistance, group III and IV were significantly higher than group I and II in Cavitec$^{(R)}$ subgroup (P<.05). The fracture resistances of Panavia-$F^{(R)}$ subgroup were not significantly different among the groups (P>.05). Panavia-$F^{(R)}$ subgroup showed significantly higher fracture resistance than Cavitec$^{(R)}$ subgroup in group I and II (P<.05). Conclusion: Within the limitation of this study, considering fracture resistance or marginal fidelity and esthetics, a functional ceramic substructure design of the coping with slim visible surface can be used for esthetic purposes, or a thick invisible surface to support the veneering ceramic can be used depending on the priority.

• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.45-50
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• 1983

According to the worldwide decreasing tendency in raw materials and increase in wood demands since 1970, the efficient utilization of raw materials was required internationally. Therefore this study dealt with the dimensional characteristics of branchwood fiber of Quercus serrata Thunb for the complete utilization of whole tree. According to the branch individuals, parts and positions within a tree, fiber length, width and wall-thickness were measured. The results obtained are as follows: 1) As the height of individual branchwood increases from ground toward, fiber length and width, and wall-thickness decreased linearly and their regression equations obtained, were Y=770.03-22.643X, Y=27.444-0.71385X and Y=12.308-0.57320X respectively 2) From the main stem to branch in distal direction, fiber length, width and wall-thickness linearly decreased and their regression equations obtained were Y=752.70-0.6724X, Y=26.152-0.0084867X and Y=11.258-0.006205X, respectively. 3) As the radial direction from pith to hark increases, fiber length, width and wall-thickness increased linearly and their regression equations obtained were Y=679.73+11.231X Y=25.382+0.0925X and Y=10.521+0.11787X, respectively. 4) Mean value of fiber length, width and wall-thickness were 625-765, 26 and $11{\mu}m$, respectively.

• Korean Journal of Ichthyology
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• v.17 no.1
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• pp.36-42
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• 2005

Histological observations on the barbels of catfish (Siluridae) in Korea are reported. The mandibular barbel of Far Eastern catfish, Silurus asotus, has epidermis and dermis surrounding an axial rod of cartilage. The stratified epidermis embodies mucous cells, club cells, and taste buds. The mucous cells, which are thin rims of basophilic cytoplasm, and the taste buds, which are basophilic, are located at the surface and the distal portion of the epidermis, respectively. The basement membrane lies between the epidermis and dermis except in places of dermal papillae. The dermis is made up of loose connective tissue fibers enclosing nerve bundles and blood vessels. The central region of cartilage is innermost and enclosed within muscle layers. The mandibular barbel of slender catfish, S. microdorsalis, has an identical structure to those of the Far Eastern catfish however, the percentage thickness of epidermis in the upper and lower parts of the barbel and the number of taste buds in the upper and middle parts of the barbel are different from those of Far Eastern catfish. This study shows that the mandibular barbels in Far Eastern catfish and slender catfish are of a stiff and flexible type.