• Journal of Acupuncture Research
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• v.22 no.3
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• pp.13-22
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• 2005

By extracting the sample of Ulmus davidiana Planch(Ulmaceae), which was known to have the protection of damaged organ and the anti-inflammation action, it was experimented whether it is available for the application of treatment of osteoporosis. In the previous experiment, the extracts from Ulmus davidiana Planch(Ulmaceae) were confirmed to inhibit Cathepsin K through treating the cell of long bone, which contains osteoclast. Through this, it is suggested that Ulmus davidiana Planch(Ulmaceae) can play a role of prodrug as an inhibitor of absorbing bone ash in the treatment of osteoporosis. In the present experiment, a research in vitro Ulmus davidiana Planch(Ulmaceae) on the growth and sensibilization of osteoblast in a state that induced osteosis by using the cell tissue of MC3T3-El pre-osteoblastic was conducted. As a result, it could be confirmed that Ulmus davidiana Planch(Ulmaceae) has the strengthening function by enhancing the dosage and the activity of ALP depending on the time. The dosage was observed at the minimum of $50{\mu}g/m{\ell}$ and the maximum of $150{\mu}g/m{\ell}$. The enhancement in bone morphogenetic protein-2 at $100{\mu}g/m{\ell}$ UD could be observed, and it also increased the concentration of ALP mRNA within the cell of MC3T3-El. At $60{\mu}g/m{\ell}$ UD which indicated a little increase in Type I collagen mRNA for a long time of culture. However, it was shown to sharply inhibit the expression of gene in the culture between 15-20 days. These results suggest that Ulmus davidiana Planch(Ulmaceae) has an influence upon bone metabolism through thje sensibilization of osteoblast. Therefore, it could be known that utilized Ulmus davidiana Planch(Ulmaceae) can be positively applied for the general disease of bone metabolism through future studies.

• Journal of Oral Medicine and Pain
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• v.32 no.3
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• pp.337-346
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• 2007

This study aimed to evaluate a relation of bruxism with clinical effects of botulinum toxin type A(BTX-A) injection. 5 bruxers and 5 nonbruxers with bilateral masseter hypertrophy were participated in this study. After injecting 25 unit of BTX-A(Allergen Inc, $Botox^{(R)}$) into each masseter muscle, the thickness of masseter(Mm) and anterior temporalis(Ta) muscles was measured by ultrasonography and the maximum bite force was evaluated during a 9-month period. Self-estimation on the recovery of occlusal force during mastication was done as well. Regardless of presence of bruxsim, all subjects showed significantly reduced Ms thickness(p<0.001) and maximum bite force at $1^{st}$ molars(p=0.027) with their peak at 3 months after injection, which then started to return. No significant difference was observed in Ta thickness and the bite force at the central incisors. While self-estimated occlusal force was the least at 2 weeks after injection and then rapidly returned to the baseline level with full recovery at the time of 6 to 9 months after injection, the maximum bite force measured by bite force recorder did not recover the original value, particularly in the nonbruxer group. It is assumed that nocturnal bruxism can influence recovery of atrophic masseter and decreased occlusal force due to BTX-A injection. These findings suggest a need of occlusal appliance to control bruxism or clenching habit for longer clinical effect of BTX-A injection.

• Journal of the Korean GEO-environmental Society
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• v.15 no.5
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• pp.47-56
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• 2014

In winter season, the pore water inside the ground freezes and thaws repetitively due to the cold air temperature. When the freezing-thawing processes are repeated on the ground, the change in soil particle structure occurs and thus the damage of the infrastructure may be following. This study was performed in order to investigate the stiffness change of soils due to the freeze-thaw by using elastic waves. Sand-silt mixtures are prepared with in the silt fraction of 40 %, 60 % and 80 % in weight and in the degree of saturation of 40 %. The specimens are placed into the square freezing-thawing cell by the temping method. For the measurement of the elastic waves, a pair of the bender elements and a pair of piezo disk elements are installed on the cell, and a thermocouple is inserted into soils for the measurement of the temperature. The temperature of the mixtures is decreased from $20^{\circ}C$ to $-10^{\circ}C$ during freezing, is maintained at $-20^{\circ}C$ for 18 hours, is gradually increased up to the room temperature of $20^{\circ}C$ to thaw the specimens. The shear waves, the compressional waves and the temperature are measured during the freeze-thaw process. The experimental result indicates that the shear and the compressional wave velocities after thawing are smaller than those of before freezing. The velocity ratio of after thawing to before freezing of shear wave is smaller than that of the compressional wave. As silt fraction increases from 40 % to 80 %, the shear and compressional wave velocities are gradually increased. This study suggests that the freezing-thawing process in unsaturated soil loosens the soil particle structure, and the shear wave velocity reflects the effect of freezing-thawing more sensitively than the compressional wave velocity.

• Journal of The Korean Association For Science Education
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• v.18 no.4
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• pp.463-472
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• 1998

Biotechnology is the process of using biological system for the production of materials. Genetic engineering, a subset of biotechnology, is the process of altering biological systems by the purposeful manipulation of DNA It is a new field in biology and no topic in biology is more likely to impact our personal lives and is therefore more worthy of our attention and understanding. The purpose of this study was to investigate students' understanding of the concepts of biotechnology, and a test tool which is made up of 20 basic questions was developed for the study. The subject of this study was high school students and the sample size was 486. In order to find out the source of students' misunderstanding, we also analysed high school textbooks and teachers were given the same tool applied to students. Two-way ANOVA was used for the analysis. Major findings of this study are as following; 1. Mean score of students was 41, and there was a significant difference between the scores of boys and girls(p<0.05). Female students scored higher than male students. The variables "region" and "major" had no significant influence. 2. Students' the most misunderstood concepts were "monoclonal antibody" and "gene cloning". Many students thought that a plamid DNA originally has a useful DNA in it, which is apparently wrong. 3. Mean score of teachers was 82, and the variabes of gender and career did not have statistically significant influence on the result(p>0.05). 4. Teachers got the lowest scores on the concepts of "gene therapy", "the accomplishment of biotechnology in agriculture and medicine", and "plasmid DNA". The results of item analysis implied that teachers' misunderstanding might be a part of the sources of students' misunderstaning. 5. Out of 18 basic concepts selected in the study, only 10 concepts were explained well enough in most textbooks. The results of item analysis indicated that textbooks also could be a part of the source of students' misunderstanding.

• Tuberculosis and Respiratory Diseases
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• v.48 no.6
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• pp.837-852
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• 2000

Backgrounds : Today, tuberculosis cannot only be cured medically, but also controlled by public health. Despite the overall worldwide decline in tuberculosis, the disease continues to be a significant problem among developing countries and in the slums of large cities in some industrialized countries. Particularly, this communicable disease has come into the public health spotlight because of its resurgence in the 1990's. our country has been operating the Korean National Tuberculosis Control Program since 1962, focusing around public health centers. Therefore, this study aims to compare the effectiveness of tuberculosis control activities, one of the major public health activities in Korea, by producing indexes, such as the yearly registration rate per 100,000 population and treatment compliance of tuberculosis on in small areas (communities). Methods : This work was accomplished by constructing a time-series analytic model using data from "1980~2000: the Yearly Statistical Report" with patient registry data of 234 City. County. District public health centers and by identifying the factors influencing the tuberculosis indexes. Results : The trends of pulmonary tuberculosis positive point prevalence and pulmonary tuberculosis negative point prevalence on X-ray screening have declined steadily, beginning in 1981 and continuing to 1998 by region (city, county, district). Although the tuberculosis mortality rate steadily shows a declining trend by year and region, but Korea still ranks first among 29 OECD countries in 1998, with a tuberculosis mortality rate of 7.1 per 100,000 persons, according to the time-series analysis for fatal diseases. Conclusion : The results of the study will form the fundamental basis of future regional health care planning and the Korean Tuberculosis Surveillance System on 2000. Since the implementation of local autonomy through the Local Health Act of 1995, it has now become vita1 for each city, county, district public health centers to determine its own priorities for relevant health care management, including budget allocation and program goals.

• Tuberculosis and Respiratory Diseases
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• v.47 no.3
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• pp.365-373
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• 1999

Background: Despite widespread use of tracheostomy in intensive care unit, it is still controversial to define the best timing from endotracheal intubation to tracheostomy under prolonged mechanical ventilation. Early tracheostomy has an advantage of easy airway maintenance and enhanced patient mobility whereas a disadvantage in view of nosocomial infection and tracheal stenosis. However, there is a controversy about the proper timing of tracheostomy. Methods: We conducted a retrospective study of the 35 medical and 15 surgical ICU patients who had admitted to Ewha Womans University Mokdong Hospital from January 1996 to August 1998 with the observation of APACHE III score, occurrence of nosocomial infections, and clinical outcomes during 28 days from tracheostomy in terms of early (n=25) vs. late (n=25) tracheostomy. We defined the reference day of early and late tracheostomy as 7th day from intubation. Results: The number of patients were 25 each in early and late tracheostomy group. The mean age were $48{\pm}18$ years in early tracheostomy group and $63{\pm}17$ years in late tracheostomy group, showing younger in early tracheostomy group. The median duration of intubation prior to tracheostomy was 3 days and 13 days in early and late tracheostomy groups. Organs that caused primary problem were nervous system in 27 cases(54%), pulmonary 14(28%), cardiovascular 4(8%), gastrointestinal 4(8%) and genitourinary 1(2%) in the decreasing order. Prolonged ventilation was the most common reason for the purpose of tracheostomy in both groups. APACHE m scores at each time of intubation and tracheostomy were slightly higher in late tracheostomy group but not significant statistically. Day to day APACHE III scores were not different between two groups with observation upto 7th day after tracheostomy, Occurrence of nosocomial infections, weaning from mechanical ventilation, and mortality showed no significant difference between two groups with observation of 28 days from tracheostomy. The mortality was increased as the APACHE m score upto 7 days after tracheostomy increased, but there were no increment for the mortality in terms of the time of tracheostomy and the days of ventilator use before tracheostomy, Conclusion: The early tracheostomy seems to have no benefit with respect to severity of illness, nosocomial infection, duration of ventilatory support, and mortality. It suggests that the time of tracheostomy is better to be decided on clinical judgement in each case. And in near future, prospective, randomized case-control study is required to confirm these results.

• Proceedings of the KSCN Conference
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• 2003.11a
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• pp.1058-1059
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• 2003

학동기(만 6-12세)에 좋은 영양 공급은 일생의 성장 발육의 기초를 조성하여 지적, 사회적, 정서적 능력을 향상시킬 수 있다. 이에 초등학생의 영양문제와 식습관을 해결하는 방안의 하나로 최근 대두되고 있는 아침결식률을 낮추기 위한 ‘아침 안 거르기’ 사업을 학교와 연계 개발하여 프로그램을 진행하고 그 효과를 평가하였다. 이 연구는 서울시 강북구 관내에 위치한 4개 초등학교 5학년 학생 1026명(실험군 451명, 대조군 675명)을 대상으로 4∼9월까지 6개월간 5단계로 실시되었다. 프로그램의 효과평가를 위해 사전(실험군-학생 428명, 부모 416명, 대조군-학생 656명, 부모 589명), 사후(실험군-학생 427명, 부모 368명, 대조군-학생 608명, 부모 558명) 설문조사를 2회 실시하여 행동과 인식률 변화를 측정하였다. 프로그램은 매월 1회 담임교사가 진행하였고, 교육자료 및 홍보물은 아침먹기 캐릭터 가방걸이와 학부모의 참여를 높이고자 가정통신문과 교육내용을 함께 삽입하여 제작한 알림장, 아침먹기와 일찍자기를 실천할 실천스티커를 배포하였고 프로그램 종료 후 아침 먹기 실천달력을 제공하였다. 또 아동들 자신의 식생활을 바르게 꾸려 나갈 수 있도록 가공식품의 ‘영양표시’에 관한 교육을 함께 교육하였고, 설문조사를 통해 영양표시제에 관한 인식변화와 행동변화율을 측정하였다. 학생들의 아침식사 실천율은 매일 먹는 그룹이 실험군은 62.9%에서 69.6%로 7% 상승하였고, 전혀 먹지 않는 그룹은 11.2%에서 6.4%로 4.8% 감소하였다(p<0.001) 대조군의 경우 매일 먹는 그룹은 70.4%에서 70.2%로, 전혀 먹지 않는 그룹은 6.9%에서 6.5%로 나타났다(p<0.001). 아침식사가 건강에 미치는 영향에 대한 인식률 변화는 큰 영향이 있다고 답한 그룹이 실험군은 60.1%에서 64.8% (p<0.001)로, 대조군은 64.8%에서 57.2% (p<0.001)로 각각 변화하였다. 일찍 자기가 건강에 미치는 영향에 대한 인식률은 큰 영향이 있다고 답한 그룹이 실험군은 52.5%에서 70.7%(p<0.001), 대조군은 55.3%에서 60.2%로(p<0.001), 일찍 자기 실천에 대한 의지 변화는 11시 이전에 잘 계획이라는 그룹이 실험군은 31.9%에서 43.9%(p<0.001), 대조군은 35.5%에서 36.8%로 나타났다(p<0.001). 영양 표시에 관한 문항에서는 식품구매시 영양표시를 보고 구매한 경험이 없다는 군이 실험군에서는 58.2%에서 40.4%로 감소하였고(p<0.001), 대조군은 64%에서 53.6% (P<0.001)로 감소하였다. 영양소에 관한 지식 평가에서 짜지 않은 간식을 선택할 때 유의할 성분을 나트륨이라고 답한 그룹은 실험군은 31.7%에서 56.3%로, 대조군은 15.9%에서 23.0%로 나타나 그룹간 큰 차이를 보였다. 아침식사로 좋아하는 음식은 김치, 김치찌개, 밥, 피자, 고기, 빵, 된장찌개, 김, 햄, 계란후라이 순이었으며 싫어하는 아침음식은 피망, 고추, 양파, 김치, 시금치, 마늘, 콩, 파, 피자, 나물순으로 나타났다. 아침식사로 혼자서도 준비할 수 있는 음식은 밥, 라면, 계란후라이, 김치, 반찬, 볶음밥, 계란, 국, 햄, 씨리얼 순으로 나타났다. 부모의 인식률 변화는 가정내에 컴퓨터 설치장소로 적합하다고 생각되는 장소로 실험군의 경우 학생 방은 28.0%에서 21.6%로 6.4%감소하였고, 마루나 거실은 61.3%에서 66.0%로 5%증가하였다(p<0.001). 반면 대조군의 경우 학생 방은 28.8%에서 24.9%로 3.9% 감소, 마루나 거실은 63.4%에서 65.9%로 2.5%증가하여 실험군과 큰 차이를 보였다(p<0.001) 자녀의 늦은 취침시간과 아침식사에 관한 인식률 변화는 아침식사에 영향이 있다는 군은 실험군의 경우 78.1%에서 82.7%로 4.2% 증가하였고(p<0.05), 대조군의 경우 82.2%에서 80.5%로 감소하여 나타났다.(P<0.001) 연구결과 실험군의 경우 일주일 동안 아침을 전혀 먹지 않는 학생이 감소하고 매일 아침을 먹는 학생이 유의적으로 증가하여 아동의 아침식사 행동변화와 인식률 변화에 도움이 된 것으로 나타났다.

• The korean journal of orthodontics
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• v.30 no.4 s.81
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• pp.441-452
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• 2000

The present studies were performed to investigate the interaction of $17{\beta}$-estradiol and human growth hormone(hGH) on the proliferation of human periodontal ligament(WDL) cell. The independent effects of $17{\beta}$ estradiol and hGH on hPDL cell proliferation were investigated and the effects of hGH on hPDL cell proliferation after $17{\beta}$-estradiol pre-treatment were also investigated. Lastly, the change of hGH receptor expression in hPDL cell after $17{\beta}$-estradiol pre-treatment were investigated. The obtained results were as follows; 1. The treatment of $17{\beta}$-estradiol or hGH had no significant effects on hPDL cell proliferation. 2. After pre-treatment of $17{\beta}$-estradiol, hGH stimulated the proliferation of the hPDL cell, regardless of hHG concentration. 3. Although there was not hGH receptor in the hPDL cell, hGH receptors were expressed in hPDL cell after more than 6 hours pre-treatment of $17{\beta}$-estradiol. 4. The effect of hGH on hPDL cell proliferation was related to the hGH receptor expression. $17{\beta}$-estradiol pre-treaaent contributed to the hGH effects on the hPDL cell by stimulating hGHR expression.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.233-243
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• 2009

We have investigated the infrared spectra for CO adsorbed on silica supported nickel(Ni-Si$O_2$), silica supported copper(Cu-Si$O_2$), silica supported nickel-copper alloys(Ni/Cu-Si$O_2$) of several compositions with varying CO pressures(0.2 $torr{\sim}$50 torr) at room temperature and on pumping to vacumn at room temperature within the frequency range of 1500 $cm^{-1}{\sim}2500\;cm^{-1}$. Four bands(2059.6 $cm^{-1},\;{\sim}$2036.5 $cm^{-1},\;{\sim}$ 1868.7 $cm^{-1},\;{\sim}$ 1697.1 $cm^{-1}$) were observed for Ni-Si$O_2$, two bands($\sim$2115.5 $cm^{-1},\;{\sim}$1743.0 $cm^{-1}$) were observed for Cu-Si$O_2$ and five bands(${\sim}2123.2\;cm^{-1}$, 2059.6 $cm^{-1},\;{\sim}$2036.4 $cm^{-1},\;{\sim}$1899.5 $cm^{-1},\;{\sim}$1697.1 $cm^{-1}$) were observed for Ni/Cu-Si$O_2$. These absorption bands correspond with those of the previous reports approximately. The bands below 1800 $cm^{-1}$ were only observed with Ni metal or Ni/Cu alloy crystal plane containing step at room temperature and the ${\sim}1697.1\;cm^{-1}$ bands observed with Ni-Si$O_2$ and Ni/Cu-Si$O_2$ may be ascribed to CO molecule adsorbed on the adsorption sites near step. The bands below 2000 $cm^{-1}$ were rarely observed with Cu metal crystal plane at room temperature and the 1743.0 $cm^{-1}$ bands may be ascribed to CO molecule adsorbed on the adsorption sites near step. The band shifts of adsorbed CO with varing Cu contents from 0 to 0.5 mole fraction at the same CO pressure or at the same pumping time to vacumn were below 21 $cm^{-1}$. and comparatively small than those with other ⅠB metal addition. It may means ligand effect of Cu d electron is small.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.4
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• pp.337-349
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• 2008

Despite an improved bone reactions of Mg-incorporated implants in the animals, little yet has been carried out by the experimental investigations in functional loading conditions. This study investigated the clinical and histologic parameters of osseointegrated Mg-incorporated implants in delayed loading conditions. A total of 36 solid screw implants (diameter 3.75 mm, length 10mm) were placed in the mandibles of 6 beagle dogs. Test groups included 18 Mg-incorporated implants. Turned titanium Implants served as control. Gold crowns were inserted 3 months. Radiographic assessments and stabilitytests were performed at the time of fixture installation, $2^{nd}$ stage surgery, 1 and 3 months after loading. Histological observations and morphometrical measurements were also performed. Of 36 implants, 32 displayed no discernible mobility, corresponding to successful clinical function. There was no statistically significant difference between test implants and controls in marginal bone levels (p=0.413) and RFA values. The mean BIC % in the Mg-implants was $54.4{\pm}20.2%$. The mean BIC % in the turned implant was $48.9{\pm}8.0%$. These differences between the Mg-implant and control implant were not statistically significant (P=0.264). In the limitation of this study, bone-to-implant contact (BIC) and bone area of Mg-incorporated oxidized implant were similar to machine-turned implant. The stability analysis showed no significantly different ISQ values and marginal bone loss between two groups. Considering time-dependent bone responses of Mg-implant, it seems that Mg-implants enhanced bone responses in early loading conditions and osseointegrated similarly to cp Ti implants in delayed loading conditions. However, further investigations are necessary to obtain long-term bone response of the Mg-implant in human.