응축압이 치과용 아말감합금의 소성변형에 미치는 영향

김철위,이인학 대한치과기재학회 1984 대한치과재료학회지 Vol.11 No.1

The purpose of this paper to study the effect of condensation pressure on plastic deformation of five dental amalgams. Three conventional lathe cut alloys which were made in Korea and admixed alloy which was made by Caulk Company in U.S.A. and high copper alloy which was made in Korea were used for this study. After each amalgam alloy and mercury measured exactly by the balance was triturated by the mechanical amalgamater (Tooth Master Model 300, Samkisa). The triturated mass was inserted into the cylinderical metal mold which was 6 mm in diameter and a plunger which was 6 mm in diameter was inserted into the cylinderical metal mold and was pressed by a Universal Compressive Testing Machine with 11㎏ for 15 second, the plunger which was 6 mm in diameter was removed from the cylinderical metal mold and a guide cap was inserted into the cylinderical metal mold and a plunger which ws 4 mm in diameter was inserted into the cylinderical metal mold and was pressed by a Universal Compressive Testing Machine with 14㎏, 18㎏ and 23㎏ for one minute. The specimen was removed from the cylinderical metal mold. The deformation depth of speciman was measured with a Depth Indicator. The results were as follows; 1. The plastic deformation of dental amalgam alloy decreases with increased time from the end of trituration. 2. When condensation pressure increases from 14㎏ to 23㎏, the plastic deformation of dental amalgam alloy increases. 3. In plastic deformation of dental amalgam the conventional lathe cut and the admixed amalgam alloy were higher than anyone else. The atomized high copper alloy was higher than fine cut of conventional lathe cut alloy.

긴 관동맥병변에서 긴 스텐트삽입에 대한 임상경과 및 재협착율

김영학,박성욱,정상식,박훈기,이상곤,이일수,이철환,김재중,홍명기,박승정 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.6

성공적인 경피적 승모판 교련절개술 후 임상 경과와 재협착율

김영학,강덕현,송재관,최기준,이철환,홍명기,김재중,박성욱,박승정 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.2

사람의 개체발생중 간에서 적혈구모세포의 성숙 - 전자현미경적 연구

김경용,엄학영,양현철,이원복 대한해부학회 1997 Anatomy & Cell Biology Vol.30 No.1

청소년의 방사선조사 식품 '이해(understanding)'에 관한 전국조사 연구

김학수,박성철 한국식생활문화학회 2002 韓國食生活文化學會誌 Vol.17 No.2

This study provides a national examination on youths' 'understanding' of irradiated food. The 1,200 subjects of the survey were randomly sampled from male and female students throughout the nation, between grades five and eleven. The survey was conducted toward these samples in November 2000. The number of respondents with exposure to irradiated food was so small, amounting to only 4.0 percent of the whole sample. The core concept used in this study is 'impression'. An impression is information about a specific subject, which carries significance to an individual. The results show that the higher the grade was, the more value the contents of impression contained. Furthermore, impressions concerning atomic or nuclear energy, and radioactivity increased greatly among students in middle school and above. Providing information of effects and advantages of irradiated food was focused to increase positive impressions and decrease the negative ones more greatly than providing simple factual information. Youths showed less value-centered impressions of irradiated food and more impressions centered on fragmented facts than adults. Respondents previously exposed irradiated food were shown to acquire the most of their information from the television and newspaper media. Among six information sources presented in the survey, youths pointed out 'science and technology research institutes' as the most credible. International organizations and environmental/ consumer organizations were evaluated as having relatively high credibility. Providing simple factual information of irradiated food did not seem to bring about any difference to the intention of purchasing irradiated food. On the other hand, respondents provided with effects-included information showed an increase in such intention. Our research results of the youth show a notable difference with that of the adults. Thus, programs and strategies to enhance youths' understanding should differ from those concerning adults.

IMT-2000 위성시스템의 다중경로 페이딩 채널에서 STTD기법 성능분석

김홍철,김학성,서상우,박운용,신요안,이원철 崇實大學校 2000 論文集 Vol.30 No.1

Recently various types of transmit diversity schemes on time, frequency and space domains to overcome multipath fading have been studied. In particular, an open loop transmit diversity scheme called space-time transmit diversity (STTD) which is based on space-time block codes, is adopted in 3GPP IMT-2000 terrestrial system standard. In this paper, we apply the STTD to IMT-2000 satellite system and investigate its performance. We show that significant performance improvement can be achieved by applying the STTD to two visible satellites in IMT-2000 satellite systems.

2형 당뇨병에서 Repaglinide의 유용성에 대한 연구

박철영,김영설,이현철,장학철 대한당뇨병학회 2001 임상당뇨병 Vol.2 No.4

연구배경 : 제2형 당뇨병 환자의 치료에 새로운 약제인 repaglinide와 기존에 상용하던 gliclazide를 비교하여 repaglinide의 유효성 및 안정성을 비교 평가 하고자 하였다. 방법 : 154명의 환자를 1:1 비율로 repaglinide와 gliclazide군으로 무작위 배정하였다. 약제 투여 전에 탈락된 2명을 제외한 152명의 환자 중 127명의 환자가 투약을 마쳤다. 투약 방법은 2주간의 약제 중지 기간 후에 4주동안 약제 용량 결정 기간을 통해 결정된 용량을 8주간 지속적으로 투여 하였다. 약제 용량은 repaglinide는 0.5mg, 1mg 또는 2mg 1정을 매 주식사 전에 경구 투여하였으며, gliclazide는 80mg 1정 또는 1/2정으로 시작해 제품 설명서에 따라 투여하였다. 치료 전 후의 당화혈색소, 공복혈당, 식후혈당 및 지질대사 지표 등의 검사로 유효성을, 여러 가지 생화학적,혈액학적 검사 및 저혈당빈도 등으로 안정성을 각각 평가하였다. 결과 : 12주 투여 후 repaglinide군과 gliclazide군 모두에서 당화혈색소 및 공복혈당의 유의한 감소를 보였다. 그러나 당화혈색소 및 공복혈당의 감소 정도는 두 군간의 유의한 차이는 없었다. 60분 및 90분의 식후혈당의 변화값의 평균은 repaglinide군에서는 기저치와 비교하여 유의하게 감소하였지만, gliclazide군에서는 유의한 감소를 보이지 않았다. 그러나 두 군의 60분, 90분 및 120분에서의 식후혈당 감소 정도는 두 치료군간에 유의한 차이는 없었다. 총콜레스테롤의 값의 유의한 감소가 gliclazide군에서 있었지만 변화 정도는 두 치료군간의 차이가 없었다. 체중변화는 두 군간 통계학적으로 유의한 차이가 없었다. 두 군모두 우려할 만한 약제 이상반응은 없었다. 저혈당 증상은 gliclazide군이 repaglinide군보다 많았지만 두 군간에 유의한 차이는 없었다. 결론 : 제2형 당뇨병 환자에서 repaglinide는 혈당조절에 대하여 gliclazide와 동등한 유효성을 가지고 있으며 안전한 것으로 사료된다. Background : This study was designed to compare the efficacy and safety of repag linide with gliclazide in a 12-week open-labelled, randomized, parallel group, multi-center study of outpatients with type 2 diabetes. Methods : A total of 182 patients were screened . 154 patients were randomized in a 1:1 ratio of repaglinide (78 patients) and gliclazide (76 patients). Two randomized patients withdrew from the trial prior to receive any trial medication. At the end of trial, 127 patients completed. The study protocol included a screening visit to assess patient eligibility; a washout period of 2 weeks, a titration period of 4 weeks, and a subsequent 8 week maintenance period. Repaglinide was a dministered preprandially with the three main meals, and gliclazide was taken according to the product labeling . Results : After 12 weeks treatment, both repaglinide and gliclazide resulted in significant reductions in HbA_(1c) (p<0.001; both treatment groups) and fasting blood glucose (FBG) values (p<0 .001; both treatment groups). Significant reductions in postprandial blood glucose (PPBG) values were found in the repaglinide group at 60 minutes (p<0.05) and at 90 minutes (p<0.05). However, no significant treatment differences in HbA 1c, FBG, or PPBG were observed. Both number of patients and frequency of reported hypoglycemic events appeared to be lower in the repaglinide group than in the gliclazide group (not significant). Conclusion: Overall, the results showed that repaglinide is well-to lerated and equally effective in controlling HbA_(1c), FBG and PPBG as gliclazide.

Histochemistry에 의한 Muscle Study와 임상적 의의

張淳喆,李載澤,金柱鎬,鄭鶴仁 대한임상병리사협회 1984 임상병리사회지 Vol.16 No.1

태권도경기시 상대산소섭취량에 관한 연구

박철호,김우규,윤영학 東亞大學校附設스포츠科學硏究所 1998 스포츠科學硏究論文集 Vol.16 No.-

The purpose of this study was to investigate the distribution of VO₂max in Taekwondo competition. Subjects as a T group were seven well-trained Taekwondo players. Control group was composed of seven healthy male students who taking Taekwondo club in D university. With K4b²telemetry, VO₂max was determined for each subject by administering as treadmill exercise test(5% slope, start speed: 120m/min, increased 20m/min each 2min). Data were analyzed by ANOVA with post hoc-test The 0.05 level of significance was as critical level for the study The study has shown that covering all round in the Taekwondo competition, the Taekwondo player group was over 81% VO₂max 55.88%, 71~80% VO₂max 17.20%, below 70%, VO₂max 26.92%, and the control group was over 81% VO₂max 47.35%, 71~80% VO₂max 14.55%, below 70% VO₂max 38.10%. Putting the above-mentioned together, we can assume that in the Taekwondo competition, energy recruitment is anaerobic 55% or so, aerobic 45%. To develop performance of Taekwondo, it is fit that training have to be composed of 60% over 81% VO₂max at least. In the future, I think that it will be necessary to find how to classify the ratio of ATP-PC system which was brought about in the Teakwondo competition, that of lactate system and aerobic on the metabolism.

Styryl diphenyl phosphine oxide의 가수분해 반응메카니즘에 관한 연구

신갑철,김학진,이광일 慶尙大學校 1985 論文集 Vol.24 No.1

The rate constants for the hydrolysis of p-substituted styryl diphenyl phosphine oxide(p-H, p-Cl, p-CH_3, p-OCH_3) were determined at various pH and rate equations which can be applied over wide pH range were obtained; below pH 5.0 the rate of hydrolysis of p-substituted styryl diphenyl phosphineoxide were catalyzed by hydronium ion and above pH 8.0, the specific base catalysis were observed. However, in the range of pH 5.0-8.0 the rate of hydrolysis were independent on the pH change andno general base catalysis were observed at pH 4.75. The substituent effects on the hydrolysis of styryl diphenyl phosphine oxide derivatives were also studied. On the basis of these results, the hydrolysis mechanism of p-substituted styryl diphenyl phosphine oxide were proposed.