• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1996년도 The 9th KACG Technical Annual Meeting and the 3rd Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.258-292
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• 1996

In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

• Journal of Yeungnam Medical Science
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• 제17권2호
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• pp.137-145
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• 2000

간세포암에 대한 방사선 치료의 효과를 평가하고자 1984년 1월부터 2000년 1월까지 영남대학교 의과대학 부속병원에서 간세포암으로 진단된 환자들 중에서 방사선 치료 단독 혹은 간동맥 색전술과 병합요법을 한 18명의 환자들의 의무기록과 방사선 사진을 검토하여 다음과 같은 결과를 얻었다. 남자가 15명, 여자가 3명이었으며 평균 나이는 51세였다. 복수가 4명(22.2%)에서 있었으며 간경변이 11명(61.1%)에서 있었다. 간기능은 Child-Pugh class A, B, C가 각각 6명, 3명, 2명이었다. 14명(77.8%)에서 HBs 항원 양성이었으며 anti-HCV 양성은 없었다. 사망원인은 간성혼수를 포함한 간부전이 2명(11.1%), 위장관출혈이 1명(5.6%), 암사망이 1명(5.6%), 현재 생존이 4명(22.2%)였으며 10명(55.6%)은 불명이었다. 종양의 위치는 간우염이 10례 좌염이 3례 양쪽 모두가 5례였으며, 종양의 형태는 결절형이 4례, 괴상형이 7례, 미만형이 7례였다. 8례(44.4%)에서 동정맥우회(shunt)가 있었으며 간문맥혈전증이 4례(22. 2%)에서 있었다. 병기는 I기, II기, III기, IV기 각각 0례, 5례, 4례, 9례였다. 종양의 크기(volume percentage)는 4025%(5-96)였다. 치료에 대한 반응은 partial response가 2례(11.1%), minimal response가 4례(22.2%), no change가 11례(61.1%), progressive disease가 1례(5.6%)였다. 평균 생존률은 97개월(2-25)로 반응율(response rate)은 33.3%였다. 3개월, 6개월, 12개월, 24개월 생존률은 각각 81.3%, 43.8%, 18.8%, 6.3%였다. 결론적으로, 간세포암에 있어서 방사선 치료는 생존률을 향상시키지는 못하더라도 종양의 크기를 줄이는데 효과가 있었다. 간동맥 색전술과의 병합치료가 치료효과를 강화하는 것으로 생각되나 방사선 단독 치료의 효과를 알기 위해서는 더 많은 연구가 필요할 것으로 생각된다.

• Childhood Kidney Diseases
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• 제16권2호
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• pp.73-79
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• 2012

목적: 일부 사구체 질환 그리고 말기 신부전 환자를 대상으로 한 연구들에서 특정 부위의 돌연변이와 deletion 그리고 미토콘드리아 DNA copy 수 등이 예후적인 경과와 관련이 있다는 주장이 제기되었다. 연구자들은 소아 IgA 신병증 환자를 대상으로 혈소판을 이용한 미토콘드리아 DNA 전체 염기서열 분석을 실시하였다. 방법: 인제의대 부산백병원 소아청소년과에서 신생검을 실시하여 IgA 신병증으로 확진된 7명의 환자를 대상으로 하였다. 대상 환아들은 동반된 전신질환이 없고 가족력상 신장질환이 없는 경우로 국한 하였다. 신생검 당시 혈청 크레아티닌 치와 사구체 여과율은 모두에서 정상 범위였으며, 각각의 연령 대에 정상 범위의 혈압을 보였다. 환자의 성별은 남자 4명 여자 3명 이었다. 환자들은 단백뇨의 정도에 따라 두 군으로 분류하였다. 결과: 신생검 당시 환자들의 평균 나이는 $11.5{\pm}2.2$세 였으며 최종 추적검사 당시의 나이는 평균 $17.9{\pm}3.2$세 였다. 환자들의 평균 추적관찰 기간은 평균 $7.8{\pm}3.1$년 이었다. 환자들은 입원당시 단백뇨의 정도에 따라 2군으로 분류하였다. 1군은 입원당시 단백뇨가 동반되지 않았던 환자들이며 2군은 신증후군의 임상 양상을 보인 환자들이었다. 최종 추적 관찰 당시 양군의 혈청 크레아티닌 치, BUN은 모두 정상 범위였다. 혈청 알부민 치는 2군에서 $3.7{\pm}0.6g/dL$로 1군의 $4.7{\pm}0.2g/dL$에 비해 유의하게 낮았으며(P=0.0241), 혈청 콜레스테롤치는 2군에서 $222.7{\pm}35.7mg/dL$로 1군의 $148.3{\pm}29.1mg$ 보다 유의하게 높았다(P=0.0283). 24시간 채집뇨상의 총단백량도 2군에서 $1,466.0{\pm}742.5\;gm$으로 1군의 $122.5{\pm}48.1\;gm$에 비해 유의하게 높았다(P=0.0135). 단회 소변을 이용한 단백/크레아티닌 비는 2군에서 $1.8{\pm}1.6$으로 1군의 $0.2{\pm}0.2$에 비해 높았으나(P=0.0961), 통계적인 유의성은 없었다. 2명의 환자에서 8,272-8,281(CCCCCTCTA) 부위 염기서열 누락을 관찰되었다. 단백뇨 정도에 따라 분류한 두군 모두에서 각각 한명씩 염기 서열의 누락이 있었다. 누락된 부위는 미토콘드리아 유래 발현되는 단백질 서열 등에 관련 없는 비부호화부위(non coding region) 이었다. 8,272-8,281 부위를 제외한 미토콘드리아 DNA 염기서열은 모두 정상이었다. 결론: 소아 IgA 신병증에서도 mtDNA common deletion이 증명됨으로해서 향후 소아 IgA 신병증에서 미토콘드리아의 기능 이상이 진행성 임상적 경과에 어떠한 영향을 미칠 수 있는 지에 대한 추가 연구가 필요하다고 생각한다.

• 패션비즈니스
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• 제13권6호
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• pp.125-136
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• 2009

The main objective of this research was to understand the characteristics of complementary color scheme through the analysis of contemporary women's fashion color coordination as they appear in the 'Collections'. Data collection of 115 was done through review of 'pr$\hat{e}$t-$\grave{a}$-porter Collections' of four cities; Milan, London, New York, Paris. Statistical analysis of frequency and also qualitative interpretation of characteristics of complementary color harmony characteristics which appeared in four collections were completed. The main findings were as followed; (1) Only 115 complementary color schemes out of 4968 two color combinations appeared. Compared the comparative ratios of appearance frequency between the two color combination and the complementary color harmony, London showed the highest, and followed by New York, and Milan and Paris. (2)The combined color type of 'red+green' was the most frequently appeared, and followed by 'violet+yellow' and 'orange+blue'. For the type of tone harmony, the contrast tone showed the most, and followed by the similarity and identity. According to the type of complementary color combination, the type of tone harmony used differently. Some differences showed in the types of color harmony and tone harmony between collections. (3) The complementary color scheme which shown in four collections harmonized two opposite colors mainly through the strong tone contrast and this could cause tension along with interest in the image. The complementary colors intensified and brought out the attributes each other. More details, high contrast of two complementary colors of yellow and violet created a vibrant look especially when used at higher saturation. Sometimes, however, some tone variations of two hues neutralized the strong effect and sometimes enhanced each other. When they used in similarity tones or identity tones in light colors, the tension was reduced and became softened but still presented nice harmony. In the type of 'red+green' color harmony, the various color combinations were demonstrated, mostly through tone manipulation of green color. The similarity tone harmony, which used the most, could effect a better sense of harmony and present more sophisticated looks. When used in contrast tone harmony, some changes in its own color which have only one color of two the excessive intensity led a good harmony. The 'orange+blue' color harmony was shown the least and used three tone harmony almost the same ratio. In this color harmony, blue amplified its energy and brilliance of orange and seemed to work better when one color was at a lower intensity than the other. In harmony with a similarity and an identity tone, this color harmony produces a stable and calm image. (4) The complementary scheme appeared more frequently in the S/S collections than in A/W collections and showed some differences in the types of color harmony and tone harmony between seasons, however, no big differences between collections.

• The Korean Journal of Physiology
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• 제27권2호
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• pp.185-197
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• 1993

The rostral ventrolateral medulla (RVLM) includes vasopressor neurons, which transmit activation signals to the intermediolateral nucleus (IML) of the spinal cord, where the preganglionic sympathetic nucleus is located, to raise arterial blood pressure (BP). However, controversy exists as to the possible depressor area in the RVLM and the pathway involved. The present study persued evidence far the location of depressor neurons and the pathway by simultaneously observing changes in BP and the firing rate (FR) of cardiovascular neurons (CVNs) in the RVLM during the somatosympathetic reflex (SSR) elicited by peripheral nerve stimulation, since CVNs are known to contribute to the generation of the sympathetic nerve discharge. In 42 cats, anaesthetized with $\alpha-chloralose$, single unit recording was performed, using carbon filament electrodes inserted into the RVLM, enabling estimation of the post R wave unit histogram (PR-UNlT) and the spike triggered average of sympathetic nerve discharge (STA-SND), allowing identification of CVNs. Antidromic stimulation of spinal $T_2$ segment was followed to determine whether the identified CVN projects axonal endings to the spinal cord (reticulospinal neuron). The sciatic nerve was electrically stimulated at $A\delta-intensity$ (1 mA, 0.1 ms), 1 Hz and C-intensity (10 mA, 0.5 ms), 20 Hz to elicit the depressor, and pressor responses of the SSR, respectively. Simultaneous measurement of CVN firing rate was made. Experimental results are summarized as follows. 1) 20 out of 98 CVNs had axonal projections to the spinal cord and 17 out of 98 CVNs showed FR changes during SSR. 2) Response patterns of FR and BP during SSR were classified into 8 types. 3) These 8 different response patterns could be further classified into those from pressor and depressor neurons. These results demonstrate that some CVNs were identifiable as reticulospinal neurons responding to anti-dromic stimulation and that CVNs operating as depressor neurons as well as pressor neurons exist in the RVLM, both of which are involved with SSR mediation. Therefore, evidence was found that an independent depressor pathway might be involved in the mediation of SSR.

• 한국환경복원기술학회지
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• 제11권6호
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• pp.26-37
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• 2008

The purpose of the study was to evaluate the effect of pervious pavements on reducing the surface runoff caused by rainfall. The surface runoff from twelve steel experimental beds with different pavement had been recorded every minute from May to September 2008, by the measuring system of tipping buckets(0.1mm/count) and data aquisition systems(National Instrument's Labview and DAQ boards & Autonics PR12-4). The dimension of the experimental bed was $1.5m(W){\times}2.0m(L){\times}0.6m(D)$ and eleven different kinds of vegetational(grass, grass+cubic stone, grass+hole brick), modular(brick, cubic stone, small cubic stone, wood block, interlocking block, clay brick, granular clay brick) and granular(naked soil, gravel) paving materials and concrete were applied for the comparison. Six rain events with depth over 30mm were selected and compared. The maximum depth of the rainfall selected was 137.5mm for 28 hours, and the minimum 30mm for 5 hours. The maximum rainfall per hour was 23mm/hr and the minimum 11.4mm/hr. The major findings were as follows; 1. All pervious pavement applied reduced over 75% of the surface runoff compared with concrete pavement. The grassy and porous pavements were relatively efficient in reducing surface runoff. 2. The grass was the more efficient as intercepting average 69.5mm of initial surface runoff, and maximum 77.8mm at the condition of 13.5mm/hr rainfall. The next was gravel intercepting maximum 65.5mm at the condition of 13.5mm/hr and the 40.9mm at 19.1mm/hr, average 55.7mm. 3. The modular pavements common in urban area were not good in intercepting the runoff except the 'clay granular brick' compared with others. The 'clay granular brick' showed relatively efficient intercepting average 14.1mm, which was the bigger amount than the 'grass+hole brick'. 4. The 'naked soil' were more effective than the 'concrete', 'brick', and 'interlocking block' in reducing the surface runoff, but less efficient than other materials. The capacity of the 'naked soil' to intercept the initial rainfall was similar to the 'brick'. As summary, the more grassy and porous pavement shows more effective in reducing surface runoffs.

• 한국수정란이식학회지
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• 제17권3호
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• pp.171-177
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• 2002

Glucocorticoid는 비유기 동물의 유선세포 pro-lactin receptor(PRL-R) 발현을 증가시키며, 전반적인 유선세포의 유합성 작용을 활성시킴으로 유합성 능력을 증진시킨다. 유선세포 PRL-R 발현량 증가는 유생산량 향상과 밀접한 관계를 갖는다. 본 실험은 비유중기의 재래산양의 유합성 능력을 향상시키고자, 0.05. 0.1과 0.2 g hydrocortisone을 5ml의 생리식염수에 현탁하여, 정맥투여하고 유선세포 PRL-R와 $\alpha$-유단백 질 mRNAs 발현 량을 조사하였다. 대조구로는 5$m\ell$의 생리식염수를 정맥투여 하였다. 24시간 후 유선조직을 채취하여 $\alpha$-유단백질과 PRL-R mRNA 발현량을 competitive PCR(polymerase chain reaction)로 발현량을 조사하였다. Hydrocortisone 처리 24시간 후 재래산양 유선세포의 PRL-R mRNA 발현량은 대조구의 PRL-R mRNA 발현량과 유의한 차이가 없었다. $\alpha$-유단백질 mRNA 발현은 대조구에 비하여 0.05g hydrocortisone투여구는 37%, 0.1g hydrocortisone 투여구는 630%, 0.2g hydrocortisone 투여구는 386% 증가하였다. Hydrocortison 처리에 의한 유선세포 PRL-R mRNA 발현에 변화가 없었으나 $\alpha$-유단백질 mRNA 발현 증가는 세포 내 기능성 단백질 발현과 세포 외부로 분비되는 단백질의 시간에 따른 발현양상의 차이인 것으로 사려된다. 본 연구에서 비유중기 재래산양에 hydrocortisone 투여는 $\alpha$-유단백질 mRNA 발현을 증가시키는 것으로 나타났다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.7-7
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• 2011

Quantum beam technology has been expected to develop breakthroughs for nanotechnology during the third basic plan of science and technology (2006~2010). Recently, Green- or Life Innovations has taken over the national interests in the fourth basic science and technology plan (2011~2015). The NIMS (National Institute for Materials Science) has been conducting the corresponding mid-term research plans, as well as other national projects, such as nano-Green project (Global Research for Environment and Energy based on Nanomaterials science). In this lecture, the research trends in Japan and NIMS are firstly reviewed, and the typical achievements are highlighted over key nanotechnology fields. As one of the key nanotechnologies, the quantum beam research in NIMS focused on synchrotron radiation, neutron beams and ion/atom beams, having complementary attributes. The facilities used are SPring-8, nuclear reactor JRR-3, pulsed neutron source J-PARC and ion-laser-combined beams as well as excited atomic beams. Materials studied are typically fuel cell materials, superconducting/magnetic/multi-ferroic materials, quasicrystals, thermoelectric materials, precipitation-hardened steels, nanoparticle-dispersed materials. Here, we introduce a few topics of neutron scattering and ion beam nanofabrication. For neutron powder diffraction, the NIMS has developed multi-purpose pattern fitting software, post RIETAN2000. An ionic conductor, doped Pr2NiO4, which is a candidate for fuel-cell material, was analyzed by neutron powder diffraction with the software developed. The nuclear-density distribution derived revealed the two-dimensional network of the diffusion paths of oxygen ions at high temperatures. Using the high sensitivity of neutron beams for light elements, hydrogen states in a precipitation-strengthened steel were successfully evaluated. The small-angle neutron scattering (SANS) demonstrated the sensitive detection of hydrogen atoms trapped at the interfaces of nano-sized NbC. This result provides evidence for hydrogen embrittlement due to trapped hydrogen at precipitates. The ion beam technology can give novel functionality on a nano-scale and is targeting applications in plasmonics, ultra-fast optical communications, high-density recording and bio-patterning. The technologies developed are an ion-and-laser combined irradiation method for spatial control of nanoparticles, and a nano-masked ion irradiation method for patterning. Furthermore, we succeeded in implanting a wide-area nanopattern using nano-masks of anodic porous alumina. The patterning of ion implantation will be further applied for controlling protein adhesivity of biopolymers. It has thus been demonstrated that the quantum beam-based nanotechnology will lead the innovations both for nano-characterization and nano-fabrication.

• 생물정신의학
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• 제7권2호
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• pp.191-197
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• 2000

Objectives : Risperidone is a new antipsychotic drug developed to overcome the therapeutic limitation of conventional antipsychotics. It responses to negative as well as positive symptoms by blocking both dopaminergic and serotonergic receptors, causing no significant side effects such as agranulocytosis and seizure. It is, however, not known whether it induces any serious cardiovascular side effects as evoked by other conventional antipsychotic drugs. The aims of this study were to evaluate the effect of risperidone on cardiovascular function, and to discuss the factors affecting the cardiovascular function. Methods : For 42 patients(22 males and 20 females) diagnosed as schizophrenia, schizophreniform disorder or schizoaffective disorder according to the DSM-IV classification, the cardiovascular fuctions such as heart rate, systolic and diastolic blood pressure, PR interval, QRS interval and QT interval were successively checked before and after 2 weeks and 4 weeks risperidone administration. Furthermore, variables such as body weight, Brief Psychiatric Rating Scale(BPRS), Clinical Global Impression(CGI), Extrapyramidal Symptom Rating Scale(ESRS), Anticholinergic Rating Scale(ARS), serum cholesterol level, serum triglyceride level, serum high-density-lipoprotein level, serum WBC, serum Hb, serum platelet level, prothrombin time and partial thromboplastin time were also analyzed before and after 2 weeks and 4 weeks risperidone administration. Results : 1) Risperidone treatment resulted in a significantly decreased heart rate and increased QT interval after 4 weeks administration(p<0.005 respectively). 2) The scores of BPRS and CGI were significantly decreased after 2 weeks and 4 weeks risperidone administration as compared with baseline(p<0.001 respectively). The scores of ESRS and ASRS were significantly increased after 2 weeks and 4 weeks risperidone administration as compared with baseline(p<0.001 respectively). 3) There were positive correlations between heart rate after 4 weeks and total dose(P<0.05). Blood pressure was significantly(p<0.05) correlated with sex(higher in male) and significantly(p<0.05) positive correlated with body weight. QT interval was significantly(p<0.05) correlated with sex(longer in female) and smoking history(shorter in smokers). Conclusions : Risperidone could induce significant change in heart rate and Q-T interval. Therefore, the cardiovascular safety for risperidone should be reconsidered according to the duration and dosage increase.

• 대한핵의학회지
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• 제26권1호
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• pp.72-81
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• 1992

Pharmacologic coronary vasodilation in conjunction with myocardial scintigraphy has become an accepted alternative to dynamic exercise testing for the diagnosis of coronary artery disease. Although dipyridamole has traditionally been used for this purpose, it causes frequent side effect, which at times can be life-threatening. Moreover, dipyridamole dose not elicit maximal coronary vasodilation in a substantial number of patients receiving the usual i.v. dose. Adenosine is an endogenously produced compound that has significant effects as a coronary vasodilator and rapid onset action and extremely short half-life (< 10 seconds). The diagnostic accuracy and safety profile of adenosine $^{99m}Tc-MIBI$ myocardial scintigraphy were evaluated and comparison with exercise $^{99m}Tc-MIBI$ was performed. Twenty-eight subjects underwent $^{99m}Tc-MIBI$ imaging after adenosine infusion and exercise $^{99m}Tc-MIBI$ imaging. Adenosine was infused intravenously at a dose of 0.14mg/kg/body weight per minute for 6 min and MIBI was injected at 3 minute. Adenosine caused an incerease in heart rate ($64{\pm}12$ at baseline versus $74{\pm}16$ beats/min at peak effect, p<0.001), a mild decrease in systolic and diastolic blood pressure and a slightly increase in PR interval(p; NS). Side effects were reported in 92% of patients and were mostly mild in nature and promptly resolved within 1 or 2 minutes of termination of adenosine infusion. Facial flushing (53%), chest pain (36%), mild dyspnea (39%), headache (21%), throat discomfort (21%) were frequent symptoms. ST segment depression (> 1 mm) and second degree AV block in electrocardiography occured in 11% of the patients, respectively. The overall sensitivity and specificity for individual coronary stenoses in 16 patients underwent coronary angiography were 88% and 95%, respectively. The agreement ratio of segmental perfusion between adenosine and exercise images was 92% (Kappa index=0.82). In conclusion, $^{99m}Tc-MIBI$ myocardial perfusion scintigraphy with intravenous adenosine is a feasible, safe and highly accurate noninvasive technique for the detection of coronary artery disease and results are at least comparable with those of exercise $^{99m}Tc-MIBI$ scintigraphy.