백서에서 Depulpin®과 Formocresol에 대한 치수와 치근단 조직의 반응

문형인,김선호,황윤찬,오병주,황인남,김선헌,정선와,윤창,오원만 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.4

One fifth dilution of formocresol is usually for pulpotomy of the primary teeth and emergency pulpotomy of the permanent teeth. However, the use of formaldehyde has been subjected to criticism because it may be absorbed into the blood stream and become distributed systemically, it may also alter the pulp tissue rendering it immumologically active, and have carcinogenic potential. Recently Depulpin®(VoCo., Germany) gains popularity as a devitalizing agent during root canal therapy in spite of high concentration of 49% paraformaldehyde because it facilitate devitalization of pulp and make root canal therapy easier. But there have been not enough publications about the reaction of pulp and periapical tissue caused by Depulpin. This study was performed to evaluate the histological changes in pulp and periapical tissue of rats after pulpotomy using formocresol and Depulpin and to elucidate the toxic effects of these agents. Thirty six Sprague-Dawley rats were anesthetized by intraperitoneal injection of ketamine. Maxillary first molar teeth were used for pulpotomy with formocresol and Depulpin. Rats were sacrificed after 2 days, 4 days, 1 week, 2 weeks, 3 weeks and 4 weeks respectively. Specimens were histologically observed by light microscope changes in pulp and periapical tissue. The obtained results were as follows. 1. Formocresol group A zone of fixed tissue, in which odontoblasts could clearly be defined, was present directly underneath the pulpotomy dressing in almost all teeth of this group. This was followed by an area of necrotic tissue which resembled dried out fibrous tissue with no cellular detail except some pyknotic nuclei. In the specimens of after 2 days, 4 days, 1 week, 2 weeks in which vital tissue was present. it was separated from the fibrous area by a zone of inflammation. In the specimens of after 3 weeks and after 4 weeks, inflammatory infiltrate was in the periodontal ligament adjacent to the apical foramina of the teeth. 2. Depulpin® group The area of necrotic tissue which had no cells and fibers , was present adjacent to the dressing. This was followed by dried out fibrous tissue with no cellular details except some pyknotic nucleli. A short stump of vital pulp with odontoblasts was present at the end of the canal after 2 days. Inflammatory infiltrate was in the periodontal ligament after 4 days and after 1week. Severe root resorption and necrosis of periapical tissue opposite the root resorption site were defined after 2 weeks and after 3 weeks. Periapical lesion which consist of necrotic tissue surrounded by a fibrous connective wall. was found after 4 weeks. The results indicated that Depulpin can cause more adverse reaction to the dental pulp and periapical tissue than formocresol, and further studies are needed for its clinical use with safety.

제2형 당뇨병 환자에서 Voglibose와 Acarbose의 비교임상연구

정인경,정재훈,민용기,이명식,이문규,김광원,정윤이,박중열,홍성관,이기업 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.26 No.2

연구배경:아카보스와 보글리보스는 ­glucosidase inhibitors로써 비록 약리학적 작용이나 부작용에 있어서 두 약물간에 차이가 있다는 것은 잘 알려져 있으나 당뇨병 환자를 대상으로 아직 이에 대한 두 약물간에 직접적인 비교에 대해 연구된 바는 없었다. 이에 저자등은 국내 2형 당뇨병 환자에 대해 유효성과 부작용 발현에 대해 두 약제를 비교하고자 무작위법에 의한 위약 대조군의 이중 맹검법 연구를 시행하였다. 방법:시험 약제 투여 4주간의 관찰기를 설정하여 공복혈당의 변화가 30㎎/dL 이하이고, 식후 혈당이 200㎎/dL 이상인 환자로 기타 제외 기준에 해당하지 않은 환자 53명을 대상으로 하여 보글리보스 군(24명)과 아카보스 군(29명)으로 무작위로 나누었다. 치료기간은 총 8주로 하였으며, 4주간 간격으로 혈청학적 검사와 부작용을 분석하여 치료 효과가 부작용을 평가하였다. 결과:1)혈당 변화:보글리보스군은 식후 1시간 혈당이 치료 후 4주, 8주째 의미 있게 감소하였도, 아카보스군은 식후 1시간과 2시간 혈당이 치료 후 4주, 8주째 의미있게 감소하였다. 또한 관찰기 혈당에 대한 치료 4주째 감소량은 아카보스군에서 더 큰 경향을 보였으나, 치료 8주째에는 두 군 간의 강하정도에 의미있는 차이가 없었다(p=0.569). 2)인슐린 치의 변화:보글리스 군은 식후 1시간 인슐린 치가 치료 전에 비해 치료 4주, 8주째 감소하는 경향을 보였고, 공복 인슐린이나 식후 2시간 인슐린치는 치료전 후에 의미 있는 차이가 없었다. 아카보스군에서는 치료 전후로 공복 인슐린, 식후 1시간과 2시간 인슐린치에 의미 있는 차이를 보이지 않았다. 두약제 간에 치료 전과 치료 8주사이의 식후 2시간 인슐린의 감소량이 보글리보스 군에서 의미있게 높았다(p=0.040). 3)당화혈색소:보글리보스 군은 치료 전에 비해 치료후 당화혈색소가 감소하는 경향을 보였고, 아카보스군은 치료 전에 비해 의미있게 감소하였다. 당화혈색소 변화량은 두 군간에 의미 있는 차이는 없었다(p=0.412). 4)지질대사의 변화:중성지방, 콜레스테롤, 고밀도 진단백 콜레스테롤에 대해 두 군간에 의미 있는 차이는 없었다. 5)부작용:소화기계 부작용의 빈도는 치료 4주째 보글리보스 군에서 의미 있게 낮았으나(p=0.028), 치료 8주째 부작용의 빈도는 두 군간에 의미 있는 차이가 없었다(p=0.215). 결론:2형 당뇨병 환자에서 보글리보스와 아카보스의 두 약제의 임상적 유효성과 부작용발현에 대해 비교한 결과 치료 후 8 주 후 혈당강화효과는 두 약제간에 유사한 효과를 보였으나 보글리보스군에서 4주째의 초기 위장관 부작용이 적었다. Background : Acarbose and voglibose are alpha-glucosidase inhibitors. Although different pharmacological effects and adverse abdominal events associated with the two drugs have been reported, no study directly compared acarbose and voglibose in diabetes has been undertaken. To compare the pharmacological effects and gastrointestinal adverse events between two drugs, a randomized, placebo-controlled, double-bind study was performed in type 2 diabetes patients. Methods : The period of study was 12 weeks(observation period: 4 weeks; treatment period: 8 weeks). Fifty-three patients were randomized into two groups(the acarbose group: 24 patients; the voglibose group: 29 patients). The serum glucose, insulin, fructosamine, HbA_1c, cholesterol, triglyceride and the incidence of adverse events were measured. Results : 1) The reduction of glucose from before treatment to 4 weeks after treatment was significantly higher in the acarbose group, but the change before treatment and 8 weeks after treatment in the two groups was similar(p=0.569). 2) The insulin significantly decreased after voglibose treatment(p=0.040). 3) HbAa_1c level tended to decrease in voglibose group, and there was a significant decrease after acarbose treatment. However, the change in HbA_1c level before and after treatment was similar between the two groups(p=0.412). 4) The two drugs did not cause any other changes in the total, HDL-cholesterol and triglyceride. 5) The number of patients with gastrointestinal adverse events was significantly low 4 weeks after voglibose treatment (p=0.049), but the incidence in the two groups was similar after 8 weeks(p=0.215). Conclusions : Acarbose and voglibose significantly improved postprandial hyperglycemia in diabetes. The incidence of gastrointestinal adverse events was low 4 weeks after voglibose treatment(J Kor Diabetes 26:134~145, 2002).

초음파 전파 및 산란 문제의 유한요소 해석

정현조,박문철,박윤원 한국비파괴검사학회 2002 한국비파괴검사학회지 Vol.22 No.4

초음파의 전파와 결합에 의한 산란장의 정확한 해석은 초음파 비파괴평가에서 중요한 역할을 한다. 수치해석법은 매개변수에 대한 연구를 간단하고 값싸게 할 수 있으므로 결함 탐지 확률을 높이고 결과적으로 검사의 신뢰도를 개선시키는데 도움이 된다. 본 연구에서는 초음파 전파와 산란장의 계산을 위하여 유한요소법(finite element method)을 사용하였으며, 대표적인 몇 가지 문제에 대하여 시뮬레이션을 실시하여 해석의 타당성을 검증하였다. 상용 FEM 프로그램을 이용하여 안정적인 수치해를 얻기 위한 유한요소 격자 크기와 시간 근사 스텝을 먼저 결정하였다. 2-D등방성 및 이방성 재료에서의 전파와 산란 문제를 다루었으며, 이론적 정해 또는 실험 결과가 알려진 문제를 선정하여 FEM 해석 결과와 비교, 분석하였다. The accuate analysis of ultrasonic wave propagation and scatttering plays an important role in many aspects of nondestructive evaluation. A numeracal analysis makes it possible to perform parametic studies, and in this way the probability of detection and reliability of test results can be improved. In this study, a finite element method was developed for the analysis fo ultrasonic fields, and the accuracy of results was checked by solving several representative preblems. The size of element and the integral time step, which are the critical components for the convergence of numerical results, were determineed in a commercial finite element code. Several propagation and scattering problems in 2-D isotropic and anisotropic materials were solved and their results were compared with known analytical or experimental results.

PC U형의 단면을 사용한 포스트텐션된 넓은 보-기둥 내부접합부의 비탄성 거동

최윤철,임재형,문정호,이리형,권기혁 대한건축학회 2005 大韓建築學會論文集 : 構造系 Vol.21 No.1

Post-tensioned precast concrete system(PPS) consists of U-shaped precast wide beams and concrete columns. The continuity of beam-column joint is provided with the topping concrete on the PC shell beam and post-tensioning. The purpose of this paper is to evaluate the response of PPS interior beam-column joint subjected to cyclic lateral loading. To this end, the experimental investigation was performed with three half-scale specimens of interior connection. The design parameter is the ratio of beam width to column width. Test results showed that cracks were distributed well and plastic hinges spread toward midspan without any significant degradation of strength and ductility. And the specimens sufficiently resisted up to the limiting drift ratio of 0.035 given by ACI of acceptance criteria for concrete special moment frames.

소구경 미세홈 고속가공시 가공환경변화에 따른 가공성 평가

정연행,이채문,강명창,이득우,김정석 한국공작기계학회 2002 한국공작기계학회 춘계학술대회논문집 Vol.2002 No.-

High speed machining is one of most effective technologies to improve productivity. It can give great advantage for manufacture of die and Moulds. However, when the high speed machining of materials, especially in machining of micro groove, a severely thermal demage was generated on workpiece and tool. Generally, the cutting fluid is used to improve penetration, lubrication, and cooling effect. In order to rise the performance of lubrication, it contains extreme pressure agents (CI, S, P). But the environment of work room go bad by those additive. Therefore, the compressed chilly air with Oil mist system was developed to replace the conventional cutting fluid system. This paper carried out the tests to evaluate the machinability by the cutting environment in high speed micro groove machining of NAK80 (HRC40). Compressed chilly air with oil mist was ejected on the contact area between cutting edge and workpiece. The effectiveness of this developed compressed chilly air with oil mist system was evaluated in terms of tool life. The results showed that the tool life of carbide tool coated TiAIN with compressed chilly air mist cooling was much longer than with dry and flood coolant when cutting the material.

가을보리 재배기간중의 기상변화

심교문,이정택,윤성호,황규홍 한국농림기상학회 2000 한국농림기상학회지 Vol.2 No.3

The northward shift of the cultivation region of winter barley has been considered because of consecutive warm winters from the middle of 1980's. There was 1.02℃ rise in mean air temperature during winter barley cropping season from 1975 to 1998. During this period, the maximum air temperature affected the mean air temperature rise rather than the minimum air temperature. The amount of mean precipitation was 513.3mm during winter barley cropping season from 1975 to 1998 and was least in 1992. Sunshine hours has increased little by little in the all regions except rural regions. The air temperature during winter barley cropping season from 1987 to 1999 in which the winter was warm was higher than the normal air temperature(1961∼1990). On the other hand, the air temperature during winter barley cropping season from 1974 through 1986 was similar to the normal air temperature. The amount of mean precipitation during winter barley cropping season from 1987 through 1999 was similar to the normal precipitation except April. During this period, the amount of mean precipitation of April was lower by 26mm than the normal year(1961∼1990). Sunshine hours during winter barley cropping season from 1987 to 1999 decreased generally in comparison with a normal year. Considering the air temperature rise during wintering from 1987 to 1998, it might be possible to extend the cropping area of winter barley northward.

미혼 남녀의 결혼관에 대한 연구

김양희,문영소,박정윤 중앙대학교 생활과학연구소 2003 생활과학논집 Vol.17 No.-

While most of adults in the past thought that marriage was compulsory, now marriage is considered not as compulsory but as optional, which is being on a decreasing trend. Accordingly, their intention to marry, time and motive of marriage depend on the individual situation or preference rather than the standardized and uniform way. This study was conducted to analyze the intention of unmarried men and women to marriage more concretely and in depth. The survey of 316 students who took a course of 'Marriage and Family' in Chung-Ang University was conducted with a way of self-description as a method for a qualitative survey to analyze their consciousness to marriage more deeply, classifying into a total of four questions. The findings of the survey were as follows. First, in terms of the intention to marriage, 93.0% of the responders answered "I will marry", indicating the majority of the students were considering marriage positive. In addition to it, in terms of the connection of love and marriage, 61.0% of the responders answered love and marriage were connected with each other, compared to 34.0% who answered seperate. Second, in terms of the motive of marriage, realization of love topped, followed by a valuable thing, emotional stability, providing for their old age, economic stability, independence from their parents and happy married life of their parents. Third, in terms of the reason to choose single, freedom topped, following by concern at change of love, unnecessity of marriage, burden on a new family, negative image to marriage, description and escape from reality, economic responsibility and the cumbersome processes of marriage.

철근콘크리트 연속보에서 부분프리스트레스 도입에 의한 휨보강 효과에 관한 연구

한병찬,윤현도,박완신,황선경,임재형,문정호 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

A strengthening technique for reinforced concrete beams using external unbonded reinforcement offers advantages in speed and simplicity of installation over other, established, strengthening techniques. The purpose of this paper is to investigate the capabilities of a new retrofitting technique, namely external prestressing(Bow), for flexural strengthening of beams. The paper provides a general description of structural behavior of beams strengthened using the technique. Results of 2 physical tests on strengthened reinforced concrete continuous beams are reported and compared. It is shown that the technique can provide greater strength enhancement to lightly reinforced sections and that provision of deflectors enhances efficiency.

토끼의 간뇌에서 NPY 분비세포에 대한 면역조직화학적 연구

정주현,문정석,김종중,장인엽,정윤영,김흥중 조선대학교 1994 The Medical Journal of Chosun University Vol.19 No.2

The distributions of neuropeptide Y(NPY) in the diencephalon of the adult rabbit was investigated using indirect immunohistochemistry. The method showed that neuropeptide Y had a widespread distributions and was present in extremely high concentration in the hypothalamic nuclei of the rabbit. A few number of NPY-containing perikarya was found in the arcuate nucleus, paraventricular nucleus. medial to the fornix. Neuropeptide Y-immunoreactive axons and terminals in the hypothalamus were found in most hypothalamic nuclei. The highest concentrations of neuropeptide Y-containing fibers were found in the arcuate nucleus. paraventricular nucleus. and alao the supraoptic nucleus. dorsomedial hypothalamic nucleus. preoptic area showed relatively high concentration of neuropeptide Y-immunoreactive fibers. The extremely high concentations of neuropeptide Y in the bypothalamus indicate important role in many brain functions

포스트-텐션 프리캐스트 외부 넓은 보-기둥 접합부의 비탄성 거동

박상욱,최윤철,김영찬,김대중,임재형,권기혁,문정호,이리형 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

Experimental results from the cycle lateral load tests for post-tensioned precast wide beam-column connections were presented. Six exterior beam-column assemblages of half scale were tested in the laboratory. The specimens consist of U-shaped precast wide beams and concrete columns. The continuity at the beam-column joint is achieved with the topping concrete and post-tensioning. The specimens were designed with parameters of the beam-to-column depth ration and the number of tendons within column core. The test results showed that the post-tensioned precast wide beam-column connection satisfied the provisional standard by ACI of acceptance criteria for concrete special moment frames.