• Title/Summary/Keyword: 개발 방법

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Mitral Valvuloplasty using New Mitral Strip (Mitracon^{(R)}$) (새로운 Strip (Mitracon^{(R)}$)을 이용한 승모판막 성형술)

  • Kang, Seong-Sik;Kim, Sang-Pil;Song, Meong-Gum
    • Journal of Chest Surgery
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    • v.41 no.3
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    • pp.320-328
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    • 2008
  • Background: Numerous surgical devices for mitral repair have been used in the past with good results. In this study we describe a simple annuloplasty technique with using a new device ($Mitracon^{(R)}$). The aim of this study was to assess its efficacy and surgical results with using $Mitracon^{(R)}$. Material and Method: From May 2003 to October 2005, 46 patients (21 women and 25 men (mean age of $51.4{\pm}17.8$ years) with mitral regurgitation from various causes were treated with either the $Mitracon^{(R)}$ (the $Mitracon^{(R)}$ group) or the Capentier Edward rigid ring (the CE group). The median follow-up duration was 18.9 months. Result: The mean grade of mitral regurgitation before and immediately after surgery in the $Mitracon^{(R)}$ group and the CE group decreased from $3.2{\pm}0.8$ to $0.6{\pm}0.7$ and $3.4{\pm}0.7$ to $0.3{\pm}0.5$, respectively. There were no significant changes in the ejection fraction either between the two groups or before and immediately after surgery. No deaths were seen in either group. Early postoperative echocardiography of all 46 patients showed only trivial mitral regurgitation or none at all. Echocardiography at a median of 18.9 months also showed no progression in mitral regurgitation. The mean grade of mitral regurgitation in the $Mitracon^{(R)}$ group at this time point decreased from $3.2{\pm}0.8$ to $0.8{\pm}0.7$ (p<0.05). The CE group also showed a similar degree of decrease from $3.4{\pm}0.7$ to $0.3{\pm}0.6$ (p<0.05). The mitral valve area in the $Mitracon^{(R)}$ group at 1 year follow-up was $3.3{\pm}0.9cm^2$. The mitral valve area in the CE group was $2.7{\pm}0.6cm^2$. The mean mitral pressure gradient in the $Mitracon^{(R)}$ group at 1 year follow-up was $3.1{\pm}1.3$ mmHg. The mean pressure gradient in the CE group was $4.5{\pm}2.1$ mmHg, although any statistical significant difference for this between the groups was not reached. Conclusion: The present study showed the described technique to be safe and effective in the intermediate term. Because long term results are unavailable, a more extensive prospective randomized multicenter trial may be warranted to determine whether this procedure should be generally applied for repair of mitral valve disease.

Clinical Usefulness and the Accuracy of Korean Reference Equation for Diffusing Capacity (한국인 폐확산능 정상예측식의 임상적 유용성과 정확성)

  • Ra, Seung Won;Park, Tai Sun;Hong, Yoonki;Hong, Sang-Bum;Shim, Tae Sun;Lim, Chae-Man;Lee, Sang-Do;Koh, Younsuck;Kim, Woo Sung;Kim, Dong-Soon;Kim, Won Dong;Oh, Yeon-Mok
    • Tuberculosis and Respiratory Diseases
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    • v.64 no.2
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    • pp.80-86
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    • 2008
  • Background: Park et al. developed the Korean reference equation for the measurement of diffusing capacity in 1985. However, the equation has not been widely used in Korea and foreign reference equations have been popularly used. We intended to compare the clinical usefulness and the accuracy of the the Korean reference equation (Park's equation) with that of the foreign equation (Burrows' equation) that is commonly used in Korea. Methods: 1. Evaluation of clinical usefulness; Among 1,584 patients who underwent diffusing capacity ($D_LCO$) at the Asan Medical Center from July to December 2006, group A subjects included 276 patients who had different interpretations of $D_LCO$ in trials employing Burrows' equation and Park's equation. Clinical assessment was decided by consensus of two respiratory physicians. In order to evaluate the clinical usefulness of Burrows' equation and Park's equation, agreement of clinical assessment and $D_LCO$ interpretation were measured. 2. Evaluation of accuracy; Group B subjects were 81 patients with interstitial lung disease (ILD) and 39 normal subjects. The 81 ILD patients were diagnosed following a surgical lung biopsy. The accuracy of diagnosing ILD as well as sensitivity and specificity were evaluated according to the use of the reference equations (Burrows' equation and Park's equation) for $D_LCO$. Results: Agreement between clinical assessment and interpretation of $D_LCO$ was 22% for the use of Burrows' equation and 78% for the use of Park's equation. The sensitivity and specificity of the Burrows' equation for diagnosing ILD were 64.2% and 100%. The sensitivity and specificity of the Park's equation for diagnosing ILD were 90.1% and 100%. The sensitivity of the Park's equation for diagnosing ILD was significantly higher than that of Burrows' equation (p<0.001). Conclusion: The Korean reference equation (Park's equation) was more clinically useful and had higher sensitivity for diagnosing ILD than the foreign reference equation (Burrows' equation).

Assessment of Demand and Use of Fresh-Cut Produce in School Foodservice and Restaurant Industries (학교급식 및 외식업체에서의 신선편이 농산물 사용실태 및 요구도 평가)

  • Sun, Shih-Hui;Kim, Ju-Hee;Kim, Su-Jin;Park, Hye-Young;Kim, Gi-Chang;Kim, Haeng-Ran;Yoon, Ki-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.6
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    • pp.909-919
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    • 2010
  • The purpose of this study was to investigate the demand and use of fresh-cut produce in school foodservice and restaurant industries. The subjects of this survey study were 200 school nutritionists and 70 cooks or managers in the restaurant industry nationwide. The data were collected by means of self-administered or e-mail questionnaires. Data analysis was completed using the SPSS window (ver. 12.0) program including frequency, $\chi^2$-test and t-test. Survey questions assessed the general characteristic of respondents, and the supply, use, and demand of fresh-cut produce in school foodservice and restaurant industries. Over 74% of the subjects have used fresh-cut produce. Most of the school foodservice (84.0%) kept fresh-cut produce for one day, while restaurant industry (28.3%) kept them up to three days. The nutritionists of school foodservice and managers of restaurant industry considered origin and date of production as the most important factor, respectively, when fresh-cut produce were being used. Fresh-cut root vegetable, such as potato and carrot was used mostly. The main reason not to use the fresh cut produce was due to the distrust of the fresh-cut produce safety in school foodservice and cost in restaurant industry. The main problem in fresh-cut produce use was the need of rewashing (29.9%) in school foodservice and irregular size (39.0%) in restaurant industry. These results indicate that the quality standard and size specification must be prepared with production guideline of safe fresh-cut produce.

Wearable Art-Chameleon Dress (웨어러블 아트-카멜레온 드레스)

  • Cho, Kyoung-Hee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.12
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    • pp.1837-1847
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    • 2008
  • The goal of this study is to express the image of chameleons-that change their colors by light, temperature and its mood-into the sexy styles of corresponding coquettish temperamental people in Wearable Art. The method used in this study was experimenting various production mediums, including creating the textured stretch fabric, in the process of expressing the conceptual characteristics of the chameleon in Wearable Art. The concept of the work was a concoction of 'tempting', 'splendid', 'brilliant', 'fascinating', etc. that highlighted the real disposition of the chameleon. The futuristic preference of the researcher was also implicated. "Comfortable" and "enjoyable" concepts via motions were improved with the its completeness. The point of the design and production is to express symbolically the chameleon in real life, analyzing its sleek body lines, conditional colors changing, outer skins and the cubic textures. The coquettish temperamental image, the conceptual image of the chameleon, was also expressed by implication into the whole work. The entire line of this work is body-conscious silhouette. It was symbolically selected to image the outline of the chameleon that has the slim and sleek body. The exposed back is intended to express symbolically the projected back bones of the chameleon. The hood of gentle triangle line expresses the smooth-lined head part. The irregular hemlines represent the elongated chameleon's tale. The chameleon with its colors of vivid tones is characterized the colors changing by its conditions. This point was importantly treated in the working process by trying the effects that the colors are seen slightly different according to the light and angles. The material was given the effect that its surface colors are seen different in lights and angles because of the wrinkles protruded lumpy-bumpy. The various stones of red and blue tones are very similar to the skin tones of the real chameleon, and their gradation makes the effect that the colors are visibly changed with each move. The textures of the chameleon were produced via the wrinkle effect of smoke-shape, which is the result of using the elastic threads on the basic mediums stitched with 50/50 chiffon and polyester along with velvet dot patterns. The stretching fabric by the impact of the elastic threads is as much suitable for making the body-conscious line. The stones are composed of acrylic cabochon and gemstone. They are symbolically expressed the lumpy and bumpy back skin of the chameleon and produced the effect of the colors visibly different. The primary technique used in this dress is the draping utilizing the biased grains. The front body piece is connected to the hood and joined to the back piece without any seam. For the irregular hemline flares, leaving the several rectangular pieces with bias grains, they were connected by interlocking. What defines the clothes is the person in action. Therefore, what decides the completeness of clothes might be its comfortable and enjoyable feeling by living and acting people. The chameleon dress could also reach its goal of comforting and pleasing Wearable Art in the process of studying the techniques and effects that visibly differentiate the colors. It is considered as a main point of the Wearable Art, which is a comfortable enjoyable clothing tempered with the artistic beauty.

Development for Fishing Gear and Method of the Non-Float Midwater Pair Trawl Net (II) - Opening Efficiency of the Model Net according to Front Weight and Wing-end Weight - (무부자 쌍끌이 중층망 어구어법의 개발 (II) - 추와 날개끝 추의 무게에 따른 모형어구의 전개성능 -)

  • 유제범;이주희;이춘우;권병국;김정문
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.3
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    • pp.189-196
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    • 2003
  • In this study, the vertical opening of the non-float midwater pair trawl net was maintained by controlling the length of upper warp. This was because the head rope was able to be kept linearly and the working depth was not nearly as changed with the variation of flow speed as former experiments in this series of studies have demonstrated. We confirmed that the opening efficiency of the non-float midwater pair trawl net was able to be developed according to the increase in front weight and wing-end weight. In this study, we described the opening efficiency of the non-float midwater pair trawl net according to the variation of front weight and wing-end weight obtained by model experiment in circulation water channel. We compared the opening efficiency of the proto type with that of the non-float type. The results obtained can be summarized as follows:1. The hydrodynamic resistance was almost increased linearly in proportion to the flow speed and was increased in accordance with the increase in front weight and wing-end weight. The increasing rate of hydrodynamic resistance was displayed as an increasing tendency in accordance with the increase in flow speed. 2. The net height of the non-float type was almost decreased linearly in accordance with the increase in flow speed. As the reduced rate of the net height of the non-float type was smaller than that of the net height of the proto type against increase of flow speed, the net height of the non-float type was bigger than that of the proto type over 4.0 knot. The net width of the non-float type was about 10 m bigger than that of the proto type and the change rate of net width varied by no more than 2 m according to the variation of the front weight and wing-end weight. 3. The mouth area of the non-float type was maximized at 1.75 ton of the front weight and 1.11 ton of the wing-end weight, and was smaller than that of the proto type at 2.0∼3.0 knot, but was bigger than that of the proto type at 4.0∼5.0 knot. 4. The filtering volume was maximized at 3.0 knot in the proto type and at 4.0 knot in the non-float type. The optimal front weight was 1.40 ton.

The difference of image quality using other radioactive isotope in uniformity correction map of myocardial perfusion SPECT (심근 관류 SPECT에서 핵종에 따른 Uniformity correction map 설정을 통한 영상의 질 비교)

  • Song, Jae hyuk;Kim, Kyeong Sik;Lee, Dong Hoon;Kim, Sung Hwan;Park, Jang Won
    • The Korean Journal of Nuclear Medicine Technology
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    • v.19 no.2
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    • pp.87-92
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    • 2015
  • Purpose When the patients takes myocardial perfusion SPECT using $^{201}Tl$, the operator gives the patients an injection of $^{201}Tl$. But the uniformity correction map in SPECT uses $^{99m}Tc$ uniformity correction map. Thus, we want to compare the image quality when it uses $^{99m}Tc$ uniformity correction map and when it uses $^{201}Tl$ uniformity correction map. Materials and Methods Phantom study is performed. We take the data by Asan medical center daily QC condition with flood phantom including $^{201}Tl$ 21.3 kBq/mL. After postprocessing with this data, we analyze CFOV integral uniformity(I.U) and differential uniformity(D.U). And we take the data with Jaszczak ECT Phantom by American college of radiology accreditation program instruction including $^{201}Tl$ 33.4 kBq/mL. After post processing with this data, we analyze spatial Resolution, Integral Uniformity(I.U), coefficient of variation(C.V) and Contrast with Interactive data language program. Results In the flood phantom test, when it uses $^{99m}Tc$ uniformity correction map, Flood I.U is 3.6% and D.U is 3.0%. When it uses $^{201}Tl$ uniformity correction map, Flood I.U is 3.8% and D.U is 2.1%. The flood I.U is worsen about 5%, but the D.U is improved about 30% inversely. In the Jaszczak ECT phantom test, when it uses $^{99m}Tc$ uniformity correction map, SPECT I.U, C.V and contrast is 13.99%, 4.89% and 0.69. When it uses $^{201}Tl$ uniformity correction map, SPECT I.U, C.V and contrast is 11.37%, 4.79% and 0.78. All of data are improved about 18%, 2%, 13% The spatial resolution was no significant changes. Conclusion In the flood phantom test, Flood I.U is worsen but Flood D.U is improved. Therefore, it's uncertain that an image quality is improved with flood phantom test. On the other hand, SPECT I.U, C.V, Contrast are improved about 18%, 2%, 13% in the Jaszczak ECT phantom test. This study has limitations that we can't take all variables into account and study with two phantoms. We need think about things that it has a good effect when doctors decipher the nuclear medicine image and it's possible to improve the image quality using the uniformity correction map of other radionuclides other than $^{99m}Tc$, $^{201}Tl$ when we make other nuclear medicine examinations.

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Genome Type Analysis of Adenovirus Serotypes 1, 2 and 5 Isolated from Children with Lower Respiratory Tract Infections in Korea (하기도 감염 환아에서 분리된 Adenovirus 1, 2, 5 혈청형의 유전체형 분석)

  • Park, Ki-Won;Choi, Eun-Hwa;Choun, Ji-Tae;Lee, Hoan-Jong;Park, Ki-Ho
    • Pediatric Infection and Vaccine
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    • v.12 no.2
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    • pp.166-177
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    • 2005
  • Purpose : The purpose of this study was to examine the molecular epidemiology and genetic variability of adenovirus(Ad) serotypes Ad1, Ad2, and Ad5 over 14 years in Korea. Methods : A total of 382 adenoviral strains isolated from the nasopharyngeal aspirates of children with lower respiratory tract infections in Seoul, Korea from November 1990 to February 2003 were serotyped by neutralization assay with type-specific antisera. Viral DNAs were extracted from infected cell lysates by the modified Hirt procedure. Genome type(GT) was determined by DNA restriction analysis with 12 restriction enzymess(BamHI, BclI, BglI, BglII, BstEII, EcoRI, HindIII, HpaI, SalI, SmaI, XbaI, and XhoI). To evaluate the genetic relatedness, pairwise comigrating restriction fragments(PCRF) analysis was performed. Results : Of 382 strains, 33 strains(9%) were Ad1, 45 strains(12%) were Ad2, and 24 strains(6%) were Ad5. Eighteen GTs(Ad1p1-Ad1p7, Ad1a, Ad1b, Ad1b1-Ad1b3, Ad1c, Ad1d, Ad1e, Ad1e1, Ad1e2, Ad1f) among Ad1, 24(Ad2p1-Ad2p11, Ad2a, Ad2a1-Ad2a6, Ad2b, Ad2c, Ad2d, Ad2e, Ad2e1-Ad2e3) among Ad2, and 10(Ad5p1, Ad5p2, Ad5a, Ad5a1-Ad5a7) among Ad5 strains were identified. One or two strains of the vast majority of GTs were isolated during the study period while a few GTs were identified sporadically with more than 2 strains. It is notable that some GTs such as Ad1p5 and Ad5a1 appeared in cluster during a short period. In analysis of genetic relatedness, the degree of PCRFs(pairwise comigrating restriction fragments) for Ad1 varied from 79 to 99%, for Ad2, 82 to 99%, and for Ad5, 85 to 99%. Conclusion : This study established the comprehensive nomenclature systems of Ad1, Ad2, and Ad5. Diverse GTs identified in this study have crucial implications in the genomic diversity and epidemiological characteristics of Ad1, Ad2, and Ad5.

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In Vitro Properties and Biodistribution of Tc-99m and Re-188 Labeled Monoclonal Antibody CEA79.4 (Re-188과 Tc-99m 표지 단일클론항체 CEA79.4의 생체외 특성과 생체내 분포)

  • Hong, Mee-Kyoung;Jeong, Jae-Min;Yeo, Jeong-Seok;Kim, Kyung-Min;Chang, Young-Soo;Lee, Yong-Jin;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul;Lee, Seung-Jin
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.6
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    • pp.516-524
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    • 1998
  • Purpose: Radiolabeled CEA79.4 antibody has a possibility to be used in radioimmunoscintigraphy or radioimmunotherapy of cancer. We investigated the in vitro properties and biodistribution of CEA79.4 antibody labeled with Re-188 or Tc-99m. Materials and Methods: CEA79.4 was reduced by 2-mercaptoethanol to produce-SH residue, and was labeled with Re-188 or Tc-99m. For direct labeling of Tc-99m, methylene-diphosphonate was used as transchelating agent. CEA79.4 in 50 mM Acetate Buffered Saline (ABS, pH 5.3) was labeled with Re-188, using stannous tartrate as reducing agent. In order to measure immunoreactivity and the affinity constant of radiolabeled antibody, cell binding assay and Scatchard analysis using human colon cancer cells SNU-C4, were performed. Biodistribution study of labeled CEA79.4 was carried out at 1, 14 and 24 hr in ICR mice. Results: Labeling efficiencies of Tc-99m and Re-188 labeled antibodies were $92.4{\pm}5.9%$ and $84.7{\pm}4.6%$, respectively, In vitro stability of Tc-99m-CEA79.4 in human serum was higher than Re-188-CEA79.4. Immunoreactivity and affinity constant of Tc-99m-CEA79.4 were 59.2% and $6.59{\times}10^9\;M^{-1}$, respectively, while those of Re-188-CEA79.4 were 41.6% and $4.2{\times}10^9\;M^{-1}$, respectively. After 24 hr of administrations of Re-188 and Tc-99m labeled antibody, the remaining antibodies in blood were 6.32 and 9.35% ID/g respectively. The biodistribution of each labeled antibody in other organs was similar because they did not accumulate in non-targeted organs. Conclusion: In vitro properties and biodistribution of Re-188-CEA79.4 were similar to those of Tc-99m-CEA79.4. It appears that Re-188-CEA79.4 can be used as a suitable agent for radioimmunotheraphy.

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Estimation of Genetic Variations and Selection of Superior Lines from Diallel Crosses in Layer Chicken (산란계종의 잡종강세 이용을 위한 유전학적 기초연구와 우량교배조합 선발에 관한 연구)

  • 오봉국;한재용;손시환;박태진
    • Korean Journal of Poultry Science
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    • v.13 no.1
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    • pp.1-14
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    • 1986
  • The subject of this study was to obtain some genetic information for developing superior layer chickens. Heterosis and combining ability effects were estimated with 5,759 progenies of full diallel crosses of 6 strains in White Leghorn. Fertility, hatchability, brooder-house viability, rearing- house viability, laying-house viability, age at 1st egg laying, body weight at 1st egg laying, average egg weight, hen-day egg production, hen-housed egg production, and feed conversion were investigated and analyzed into heterosis effect, general combining ability, specific combining ability and reciprocal effect by Grilling's model I. The results obtained were summarized as follows; 1. The general performance of each traits was 94.76% in fertility, 74.05% in hatchability, 97.47% in brooder-house viability, 99.72% in rearing-house viability, 93.81% in laying-house viability, 150 day in the age at 1st egg laying, 1,505g in the body weight at 1st egg laying, 60.08g in average egg weight, 77.11% in hen-day egg production, 269.8 eggs in hen-housed egg Production, and 2.44 in feed conversion. 2. The heterosis effects were estimated to -0.66%, 9.58%, 0.26%, 1.83%, -3.87%, 3.63%, 0.96%, 4.23%, 6.4%, and -0.8%, in fertility, hatchability, brooder-house viability, laying-house viability, the age at 1st egg laying, the body weight at 1st egg laying, average egg weight, hen-day egg Production, hen-housed egg production and feed conversion, respectively. 3. The results obtained from analysis of combining ability were as follows ; 1) Estimates of general combining ability, specific combining ability and reciprocal effects were not high in fertility. It was considered that fertility was mainly affected by environmental factors. In the hatchability, the general combining ability was more important than specific combining ability and reciprocal effects, and the superior strains were K and V which the additive genetic effects were very high. 2) In the brooder-house viability and laying-house viability, specific combining ability and reciprocal effects appeared to be important and the combinations of K${\times}$A and A${\times}$K were very superior. 3) In the feed conversion and average egg weight, general combining ability was more important compared with specific combining ability and reciprocal effects. On the basis of combining ability the superior strains were F, K and B in feed conversion, F and B in the average egg weight. 4) General combining ability, specific combining ability and reciprocal effects were important in the age at 1st egg laying and the combination of V ${\times}$F, F${\times}$K and B${\times}$F were very useful on the basis of these effects. In the body weight at 1st egg laying, general combining ability was more important than specific combining ability and reciprocal effects, relatively. The K, F and E strains were recommended to develop the light strain in the body weight at 1st egg laying. 5) General combining ability, specific combining ability and reciprocal effects were important in the hen-day egg production and hen-housed egg production. The combinations of F${\times}$K, A${\times}$K, and K${\times}$A were proper for developing these traits. 4. In general, high general combining ability effects were estimated for hatchability, body weight at 1st egg laying, average egg weight, hen-day egg production, hen-housed egg production, and feed conversion and high specific combining ability effects for brooder-house viability, laying house viability, age at 1st egg laying, hen-day egg production and hen-housed egg production, and high reciprocal effects for the age at 1st egg laying.

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The Comparative Imaging Study on Mn-phthalocyanine and Mangafodipir trisodium in Experimental VX2 Animal Model (실험적으로 유발시킨 VX2 동물모델에서의 Mn-phthalocyanine과 Mangafodipir trisodium의 비교영상)

  • Park Hyun-Jeong;Ko Sung-Min;Kim Yong-Sun;Chang Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.1
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    • pp.32-41
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    • 2004
  • Purpose : To measure the NMR relaxation properties of MnPC, to observe the characteristics of liver enhancement patterns on MR images in experimentally implanted rabbit VX2 tumor model, and to estimate the possibility of tissue specific contrast agent for MnPC in comparison with the hepatobiliary agent. Materials and Methods : Phthalocyanine (PC) was chelated with paramagnetic ions, manganese (Mn). 2.01 g (5.2 mmol) of phthalocyanine was mixed with 0.37 g (1.4 nlmol) of Mn chloride at $310^{\circ}C$ for 36 hours and then purified by chromatography ($CHCl_3:\;CH_3OH=98:2$, volume ratio) to obtain 1.04 g $(46\%)$ of MnPC (molecular weight = 2000 daltons). The T1/T2 relaxivity (R1/R2) for MnPC were determined at a 1.5 T (64 MHz) MR spectrometer. VX2 tumor model was experimentally implanted in the liver parenchyma of rabbits. All MR studies were performed on 1.5 T. The human extremity radio frequency coil of a bird cage type was employed. MR images were acquired at 17 to 24 days after VX2 carcinoma implantation.4 mmol/kg MnPC and 0.01 mmol/kg Mn-DPDP were injected via the ear vein of rabbits. T1-weighted images were obtained with spin-echo (TR/TE=516/14 msec) and fast multiplanar spoiled gradient recalled (TR/TE : 80/4 msec, $60^{\circ}$ flip angle) pulse sequence. Fast spin-echo (TR/TE=1200/85 msec) was used to obtain the T2-weighted images. Results : The value of T1/T2 relaxivity (R1/R2) of MnPC was $7.28\;mM^{-1}S^{-1}$ and $55.56\;mM^{-1}S^{-1}$ respectively at 1.5 T (64 MHz). Because the T2 relaxivity of MnPC that bonded strongly, covalently manganese with phthalocyanine was very high, the signal intensity of liver parenchyma was decreased on postcontrast T2-weighted images and we could easily distinguish the VX2 carcinoma within the liver parenchyma. When MnPC was administrated intravenously, the tumor margin delineation was more remarkable than Mn-DPDP-enhanced images. The enhancement of liver parenchyma with MnPC persisted at relatively high levels over at least one hour after injection of the contrast agents. Conclusion : The hepatic uptake and biliary excretion of MnPC, which are similar to Mn-DPDP, suggest that this agent is a new liver-specific agent. Also, MnPC seems to be used as a dual contrast agent (T1 and T2) with high T2 relaxivity. However, it is warranted that MnPC needs further investigation as a potential contrast agent for MR imaging of the liver. That is, further characterizations of MnPC are needed in vivo and in vitro before clinical trials. The diagnostic potential of MnPC will also have to be examined more in the animal models of additional types.

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