• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.135-144
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• 1990

The vascular responses to the vasoactive drugs were evaluated using aortic ring preparations obtained from propylthiouracil (PTU)-treated rats. The body weights and the levels of serum thyroxine $(T{_4})$ and triiodothyronine $(T{_3})$ were significantly decreased in propylthiouracil-treated rats as compared with those in age-matched control rats. The contractile responses to norepinephrine and potassium and calcium ions were significantly attenuated in aortic rings of PTU-treated rats 4 weeks after when compared with those from age-matched control animals. By the PTU treatment, however, the sensitivity to norepinephrine but not to calcium was decreased while the maximal responses to norepinephrine and calcium were reduced together. The attenuated contractile responses to the vasoconstrictors in PTU-treated rats are ascribed to the decreased ability of the muscle cells to contract. On the other hand, the relaxation responses induced by acetylcholine and histamine (endothelium-dependent relaxants) and isoproterenol and sodium nitroprusside (endothelium-independent relaxants) had tendencies to be augmented in aortic rings of PTU-treated rats when compared with those of age-matched control animals. However, the sensitivities to the endothelium-independent relaxants were different between PTU-treated and control rats whereas those to the endothelium-dependent relaxants were not. These results suggest that the altered vascular responsiveness in the PTU-treated rats seems to be due to the alteration of smooth muslce cells rather than the Influence of endothelium, and that this change is slowly progressive after hypothyroidism is evident.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.677-683
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• 2008

The purpose of study was to compare the prevalences of severe early childhood caries(S-ECC) using two different diagnostic criteria. The subjects of this study included 401 preschool children from 36 to 71 months of the randomly selected seven nurseries in Iksan city. Severe early childhood caries was defined as (1) 1 or more cavitated, missing (due to caries), or filled smooth surfaces in primary maxillary anterior teeth or (2) a decayed, missing, or filled score of ${\geq}$4 (age 3), ${\geq}$5 (age 4), or ${\geq}$6 (age 5) surfaces. The prevalence determined by maxillary anterior caries and the prevalence determined by dmfs were 26.7%, 28.9% in 3 years, 32.4%, 30.4% in 4 years, 39.4%, 41.3% in 5 years, and 35.4%, 35.9% in all, respectively. The results suggest that the two diagnostic criteria of the severe early childhood caries yield almost the same results.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.58.1-59
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• 2021

Exploration of asteroids' internal structure is essential for understanding their evolutional history. It also provides a fundamental information about the history of coalescence and collision of the solar system. Among several models of the internal structures, the rubble-pile model, confirmed by the near-Earth asteroid (25143) Itokawa by Hayabusa mission [1], is now widely regarded as the most common to asteroids with size ranging from 200 m to 10 km [2]. On the contrary, monolithic and core-mantle structures are also possible for small asteroids [3]. It is, however, still challenging to look through the interior of a target object using remote-sensing devices. In this presentation, we introduce our ongoing research conducted at Seoul National and propose an idea to infer the internal structure of Apophis using available instruments. Itokawa's research provides an important benchmark for Apophis exploration because both asteroids have similar size and composition [4][5]. We have conducted research on Itokawa's evolution in terms of collision and space weathering. Space weathering is the surface alteration process caused by solar wind implantation and micrometeorite bombardment [6]. Meanwhile, resurfacing via a collision acts as a counter-process of space weathering by exposing fresh materials under the matured layer and lower the overall degree of space weathering. Therefore, the balance of these two processes determine the space weathering degrees of the asteroid. We focus on the impact evidence on the boulder surface and found that space weathering progresses in only 100-10,000 years and modifies the surface optical properties (Jin & Ishiguro, KAS 2020 Fall Meeting). It is important to note that the timescale is significantly shorter than the Itokawa's age, suggesting that the asteroid can be totally processed by space weathering. Accordingly, our result triggers a further discussion about why Itokawa indicates a moderately fresh spectrum (Sq-type denotes less matured than S-type). For example, Itokawa's smooth terrains show a weaker degree of space weathering than other S-type asteroids [7]. We conjecture that the global seismic shaking caused by collisions with >1 mm-sized interplanetary dust particles induces granular convection, which hinders the progression of space weathering [8]. Note that the efficiency of seismic wave propagation is strongly dependent on the internal structure of the asteroid. Finally, we consider possible approaches to investigate Apophis's internal structure. The first idea is studying the space weathering age, as conducted for Itokawa. If Apophis indicates a younger age, the internal structure would have more voids [9]. In addition, the 2029 close encounter with Earth provides a rare natural opportunity to witness the contrast between before and after the event. If the asteroid exhibits a slight change in shape and space weathering degree, one can determine the physical structure of the internal materials (e.g., rubble-pile monolithic, thick or thin regolith layer, the cohesion of the materials). We will also consider a possible science using a seismometer.

• Tuberculosis and Respiratory Diseases
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• v.63 no.3
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• pp.289-293
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• 2007

Lymphangioleiomyomatosis (LAM) is a rare disease that affects females of reproductive age. It is characterized by the abnormal proliferation of smooth muscle cells in the lung and along the axial lymphatics. We report a case of lymphangioleiomyomatosis presenting as a lung mass. The patient visited the emergency room because of dyspnea upon exertion. The chest X-ray showed a lung mass in the right lower lung field and a pneumothorax in the left lung. Chest computed tomography revealed a $5{\times}3cm$ sized mass in the right lower lobe and multiple thin-walled small cysts scattered in both lungs. Transbronchial biopsy of the lung mass was performed. The biopsy specimen showed atypical smooth muscle cell proliferation and cystic dilatation of the terminal bronchioles, which confirmed the diagnosis of lymphangioleiomyomatosis. To the best of our knowledge, this is the first case of lymphangioleiomyomatosis presenting as a lung mass.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.3
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• pp.176-183
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• 2011

Introduction: Very high aggressiveness and recurrence are important clinical characteristics of ameloblastoma compared to the other benign tumors. Therefore, an accurate diagnosis and treatment plan is important. This study examined the association of the clinical findings and recurrence based on the radiological findings of ameloblastoma. In recurrent cases, these results are expected to help in the diagnosis and treatment of ameloblastoma to examine the relevance with the clinical characteristics and radiological features. Materials and Methods: For a clinical (gender, age) and radiological (location, internal pattern, size, perforation, border pattern, impacted tooth, root resorption) evaluation, this study examined 156 cases of 147 patients diagnosed with ameloblastoma, who had been treated and in most cases regularly checked at the department of oral and maxillofacial surgery, Kyungpook National University Hospital, between January 1993 and December 2009. For a recurrent rate evaluation, a more than 3 years follow-up period is needed. Accordingly, 116 patients diagnosed with ameloblastoma between January 1994 and December 2007 were investigated. Results: The recurrence rate in all cases was 6.1% but was 7.8% in cases with follow-up periods more than 3 years. The male-to-female ratio was 3:2, showing a slight male predilection. Ameloblastoma had a peak occurrence in the second decade of life followed by the fourth decade of life. The mandibular angle area is the most frequent site of ameloblastoma (50.8%) in the jaws. Six cases of unilocular (7.8%) and 3 cases of multilocular (7.7%) ameloblastomas recurred. Seven cases of smooth (10%) and 2 cases of irregular (4.3%) ameloblastomas recurred. No cases of ameloblastomas without perforation of the cortical bone (0%) and 9 cases with a perforation of cortical bone (11.1%) recurred. Four cases of the ameloblastomas with impacted teeth (11.4%) and 5 cases of ameloblastomas without impacted tooth (6.2%) recurred. Seven cases of ameloblastomas with root resorption (10.9%) and 2 cases of ameloblastomas without root resorption (3.8%) recurred. Conclusion: A multiple smooth margin, unilocular ameloblastoma with an impacted tooth, root resorption tends to recur more easily. Therefore, they need to be treated more carefully and require a a longer follow-up.

• Journal of Korean Dental Hygiene Science
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• v.3 no.2
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• pp.9-18
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• 2020

This study analyzed 183 for dental hygienists working at dental hospitals and clinics in Daegu to survey organizational socialization of them. The adversity index of the study subjects averaged 58.60±9.16 points out of a total score of 100, with the highest individual initiative of 16.58±3.09 points, and a low of 13.86±3.66 points for continuity of the situation. Organizational socialization averaged 123.40±12.82 points out of 190, with the highest personal characteristics of 30.37±3.71 points, and the lowest occupational identity of 10.34±1.94. The adversity index of the participants was significantly higher in graduate school or higher (F=3.112, p=0.047), the lower the intensity of their work (F=2.860, p=0.060), and the more often the degree of turnover (F=5.196, p<0.006). In organizational socialization, age (F=9.290, p<0.001), educational background (F=8.655, p<0.001), and higher position (F=5.425, p=0.005) were significantly higher when working in hospitals (F=4.534, p=0.012). The higher the position (F=5.425, p=0.005), the higher the work experience (F=5.320, p=0.002), the lower the turnover (F=22.935, p<0.001), and the highrer the intensity of the work(F=7.02, p<0.001). The study subjects' organizational socialization showed a significant correlation with the adverse event index (r=0.395, p<0.000). The regression analysis using organizational socialization as a dependent variable showed that the degree of turnover (β=0.300, p<0.001) had a significant effect on organizational socialization. The total explanatory power of this variable was 41.6%, with significant effects on individual initiative (β=0.255, p<0.000) and personal control (β=0.180, p<0.009) among the adverse events index. The above findings confirmed that a high adverse event index of dental hygienists has the effect of increasing organizational socialization. Dental hygienists' adversity index is average, meaning they live a smooth life in smooth conditions, however, when major adversity arises, organizational socialization is highly necessary. In addition, to strengthen the organizational socialization of new dental hygienists, as well as experienced dental hygienists, a customized program should be administered to raise the adverse index of dental hygienists, and provide a human management tool through regular confirmation of the program.

• Korean Journal of Biological Psychiatry
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• v.13 no.4
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• pp.279-288
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• 2006

Objectives : We investigated the association of SNP A and P1763 polymorphisms on dystrobrevin binding protein 1(DTNBP1) gene with smooth pursuit eye movement(SPEM) abnormality in Korean schizophrenic patients. Methods : We measured SPEM function in 217 Korean schizophrenics(male 116, female 101) and divided them into two groups, one is a good SPEM function group and the other is a poor SPEM function group. We then analyzed SNP A polymorphism and P1763 polymorphism on DTNBP1 gene from their DNAs extracted from their blood. We compared the differences of genotype and allele distributions of the two polymorphisms on DTNBP1 gene between the two groups. Results : The Ln S/N ratio(mean${\pm}$SD) of the good SPEM function group was $4.39{\pm}0.33$ and the ratio of poor SPEM function group was $3.17{\pm}0.71$. There were no statistically significant differences of age and male/female ratio between the two groups. There were no significant differences of genotype or allele distributions of the SNP A polymorphism and P1763 polymorphism on DTNBP1 gene between the two schizophrenic groups divided by SPEM function. Conclusion : The results suggest that SNP A polymorphism and P1763 polymorphism on DTNBP1 gene might not be related to SPEM function abnormality in schizophrenia.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1208-1214
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• 2007

Three male Gayal, two years of age and with a mean live weight of $203{\pm}26$ kg, and three adult Yunnan Yellow Cattle, with a mean live weight of $338{\pm}18$ kg were fed a ration of pelleted lucerne hay and used to collect rumen fluid for in vitro measurements of digestibilities and gas production from fermentation of a range of forages. The forages were: bamboo stems, bamboo twigs, bamboo leaves, rice straw, barley straw, annual ryegrass hay, smooth vetch hay and pelleted lucerne hay. There were significant (p<0.05) effects of the source of rumen fluid on in vitro dry matter digestibility (IVDMD) and gas production during fermentation of forage. For the roughage of lowest quality (bamboo stems and rice straw), gas production during fermentation was higher (p<0.05) in the presence of rumen fluid from Gayal than Yunnan Yellow Cattle. Differences for these parameters were found for the better quality roughages with gas production being enhanced in the presence of rumen fluid from Yunnan Yellow Cattle. Moreover, the IVDMD of investigated roughages was significantly higher (p<0.05) in Gayal than Yunnan Yellow Cattle. The results offer an explanation for the positive live weight gains recorded for Gayal foraging in their natural environment where the normal diet consists of poor quality roughages.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.5
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• pp.431-436
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• 2010

Purpose: It is estimated that the odontogenic keratocyst (OKC) makes up 10% to 12% of all developmen-tal odontogenic cysts. The lesion has been of particular interest because of its specific histopathologic fea-ture, high recurrence rate, and aggressive behavior. Materials and Methods: We investigated 266 OKCs of Korean patients for the sex of patient, the age of the patient, the location of OKC, the recurrence rate related to radiographic impression. Results: The male-to-female ratio was 1.47:1, showing a slight male predilection. Odontogenic keratocysts had a peak of occurrence in the third decade of life. The mandibular angle and ascending ramus area (49.6%) is the most frequent site of OKCs in the jaws. Fourteen cases of unilocular (12%) and 5 cases of multilocular (20%) OKCs recurred. Thirteen cases of smooth (12.9%) and 6 cases of lobulated (14.6%) OKCs recurred. Seventeen cases of OKCs without perforation of cortical bone (12.5%) and 2 cases of OKCs with perforation of cortical bone (33.3%) recurred. Fifteen people of patients with single lesion (12.2%) and 4 people of patients with multiple lesions (66.7%) recurred. Conclusion: In this resul, we consider multiple odontogenic keratocysts can recur more easily. So we have to treat them more carefully and need long-time follow-ups.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.639-643
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• 2010

Purpose: Cryptotia is a congenital deformity in which the upper third of the auricle is buried under the temporal skin. It is rare in Caucasians, yet it is more common in Asians. Although a variety of methods to treat cryptotia have been introduced, there is still no acceptable single procedure that can successfully manage this deformity in its entity. We present a triangular V-Y advancement flap and rhomboid flap for correcting cryptotia that can overcome the diverse shortcomings of the conventional methods. Methods: This operative method was used to correct 18 auricles in patients ranging in age from 4 to 33 years. A triangular flap was prepared over the auricle by making a skin incision according to Ohmori's method. Then a rhomboid flap with a side length of about 8 to 10 mm that sets the lower portion as a pedicle in the anterior region was prepared to supplement the contracted portion of the helix. The cartilage deformity was corrected by the banner flap or the radiating cartilage incisions with cartilage graft or high density polyethylene graft. Results: We have treated 16 patients with severe cryptotia using this method and have obtained good aesthetic results. All cases showed widened scaphoid fossa and smooth triangular fossa of antihelix. There were no major postoperative complications, such as necrosis or infection of the flaps. Conclusion: Correction of cryptotia using the triangular V-Y advancement flap and rhomboid flap is useful a method for certain conditions, when a severe contraction of the helix is present.