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Studies on the Factors Affecting Barley Injury Caused by Herbicides in Drained Paddy Field (제초제에 의한 답리작맥 약해발생 요인구명에 관한 연구)

  • Whan-Seung Ryang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.14
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    • pp.147-157
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    • 1973
  • I. The effect of excessive soil moisture(at the time of germination) on germination of barley and crop damage of herbicides was investigated. Machete(Butachlor) and TOK(Nitrofen) were treated, respectively, at the rate of 150g ai/10a on each pot whose different soil moisture content was controlled by suppling 30, 40, 50 and 60ml of water per 100gr of air-dried soil, respectively. The results are summarized as follows: 1. Excessive soil moisture beyond field moisture capacity caused great inhibition, from 20 to 100%, of the germination of barley even at untreated pots(check pots). Also, further development of root and growth of barley were greatly inhibited even though the seeds germinated. 2. The same tendency in inhibition of germination and growth as at untreated pots was observed at treated pots, too. As a whole, however, the damage were heavier at treated pots. II. Wanju naked spring barley was seeded on four different soils and covered with soil to a depth of 1 em, and then Machete, TOK, Saturn and HE-314 were treated at the rate of 180, 150 and 200, 150, and 250g ai/10a, respectively, and the effect of soil texture on crop damage of the herbicides was investigated. The results are summarized as follows: 1. Machete(emulsion and granule, at 180g ai/10a) The degree of crop damage was quite different from one soil texture to another: while almost no crop damage was observed on a clay loam soil regardless of the type of formulation, the damage became heavier as the soil texture became sandier as sandy clay loam, volcanic ash loam and sandy loam, and great inhibition of growth was observed on sandy loam soil. In general heavier damage was caused by the application of emulsion than by granular formulation. 2. TOK(Wettable powder, at 150, 250g ai/l0a) Almost the same tendency as in the application of Machete was observed, and the damage became heavier as the application rate increased. 3. Saturn(at l50g ai/l0a) No great difference in crop damage among soil textures was observed. 4. HE-3l4(at 250g ai/l0a) Almost no difference in crop damage among soil textures was observed at this rate of 250g ai/l0a. III. To study a difference of crop damage on soil covering depth(4 levels), 9 herbicides(TOK, MO, HE-3l4, Machete, Saturn, Simetryne, Simazine, Gesaran, Lorox) were treated on the pots with two different soils, and the effect of soil covering depth on crop damage of the herbicides was investigated. The results obtained in this experiment are summarized as follows: Light Clay Soil 1. The growth of barley in relation to depth of soil covering at check pots followed the order vigorous to weak; lcm>1.5cm>0.5cm>0cm. And in case of 0 and 0.5cm covering the growth of barley was very poor. 2. The damage at 0 and 0.5cm covering at treated pots was very severe, but Saturn, Machete, MO and TOK at 100 to l50g ai/l0a, respectively and He-3l4 at 250 to 375g ai/l0a were relatively safe to barley at the depths of lcm and above. 3. Simazine, Lorox and Simetryne caused slight damage even at 1.5cm covering. Sandy Loam Soil The growth of barley in relation to depth of soil covering at untreated pots followed the order, from vigorous to weak; 1.5cm 0.5cm 3cm 5cm. While MO was safe to barley at 1.5cm covering, for other chemicals more than 3cm covering was require for safe use. Machete and Saturn at 100g ai/l0a, and HE-3l4 at 250g ai/l0a was relatively safe at more than 3cm covering. Simazine, Lorox, Simetryne and Gesaran were unsafe on sandy soil regardless of covering depth.

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Characterization and Evaluation of Melanocortin 4 Receptor (MC4R) Gene Effect on Pork Quality Traits in Pigs (돼지 Melanocortin 4 Receptor (MC4R) 유전자의 육질연관성 분석)

  • Roh, Jung-Gun;Kim, Sang-Wook;Choi, Jung-Suk;Choi, Yang-Il;Kim, Jong-Joo;Choi, Bong-Hwan;Kim, Tae-Hun;Kim, Kwan-Suk
    • Journal of Animal Science and Technology
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    • v.54 no.1
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    • pp.1-8
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    • 2012
  • This study aimed to investigate the single nucleotide polymorphisms (SNPs) of the porcine MC4R gene and validate the effect of the MC4R genotype for marker assisted selection (MAS). Six amplicons were produced to analyze the entire base sequences of the porcine MC4R gene and six SNPs were detected (c.-780C>G, c.-135C>T, c.175C>T-Leu59Leu, c.707A>G-Arg236His, c.892A>G-Asp298Asn, and c.*430A>T). Linkage disequilibrium (LD) of the six SNPs was analyzed by performing haploid analysis. There was a perfect linkage disequilibrium in c.-780C>G, c.-135C>T, c.175C>T-Leu59Leu, c.707A>G-Arg236His, and c.*430A>T. Only the c.892A>G (Asp298Asn) SNP showed a very low LD with an $r^2$ value of 0.028 and the D' value of 0.348. As a result, the two SNPs-c.707A>G (Arg236His) and c.892A>G (Asp298Asn)-were selected to extract the genotype frequencies from the 5 pig breeds by using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) genotype analysis method. The SNP frequency of c.707A>G (Arg236His) indicated the presence of the A (His) allele only in Yorkshire, while the G allele was fixed in the KNP, Landrace, Berkshire, and Duroc. Association analysis was carried out in 484 pigs with the c.707A>G (Arg236His) SNP and the meat quality traits of four different pig cross populations: a significant association was noted in crude fat, sirloin moisture, meat color, and the degree of red and yellow coloration. The frequency of the c.892A>G(Asp298Asn) SNP genotype varied among the breeds; while Duroc showed the highest frequency of the A (Asn) allele, KNP showed the highest frequency of the G (Asp) allele. Association analysis was carried out in 1126 pigs with the c.892A>G (Asp298Asn) SNP and the meat quality traits of four pig populations: a highly significant linkage was noted in the back-fat thickness (P<0.002). It was found that the back-fat thickness was higher in individuals with the AA genotype than in those with the AG or GG genotype. Thus, in this study, we verified that the c.892A>G (Asp298Asn) SNP in the pig MC4R gene has a sufficient effect as a gene marker for MAS in Korean pork industry.

The Results of Combined External Radiotherapy and Chemotherapy in the Management of Esophageal Cancer (식도암의 방사선-항암화학 병용치료결과)

  • Lee Hyun Joo;Suh Hyun Suk;Kim Jun Hee;Kim Chul Soo;Kim Sung Rok;Kim Re Hwe
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.17-23
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    • 1996
  • Purpose : To evaluate the role of combination therapy of external radio-therapy and chemotherapy in the management of advanced esophageal cancer as a primary treatment compared with radiation therapy alone. Materials and Methods : A retrospective review of evaluable 55 esophageal cancer patients referred to the Department of Therapeutic Radiology, Paik Hospital for the external radiotherapy between Jul, 1983 and Dec. 1994 was undertaken. Combined therapy patients (A group) were 30 and radiation alone patients (B group) were 25. Median age was 60 years old in A group (ranges : 42-81) and 65 years old in B group (ranges : 50-81). The male patients were 53. The fifty patients had squamous cell carcinomas. Radiation doses of 2520-6480c0y were delivered over a period of 4-7weeks, using 4MV LINAC. Chemotherapy was administered in bolus injection before, after, or during the course of external radiotherapy. The local control rate and patterns of failure according to both treatment modalities and 1, 2 year survival rates according to prognostic factors (stage, tumor length, radiation dose etc.) were analysed. Resuts : Median follow up Period was 7 months (range : 2-73 months). Median survival was 7.5 months (20 days-29 months) in A group and 5 months (20 days-73 months) in B group. The 1, 2 YSRs were $26.7\%$, $8.9\%$ in A group, $12.7\%$, $4.3\%$ in B group (p>0.05), respectively. The 1, 2 YSRs according to stage(II/III), tumor length (5cm more or less). radiation dose (5000cGymore or less) of A and B group were analyzed and the differences of survival rates of both treatments were not statistically significant. But among group B, patients who received 5000cGy or more showed significant survival benefits (p<0.05). The treatment response rates of A and B group were $43.8\%$. $25.0\%$, respectively. Complete response rate of $25.0\%$ in A and $8.3\%$ in B were achieved. The local failure and distant metastsis were $52.4\%$. $23.8\%$ in A group, $64.3\%$, $14.3\%$ in 8 group, respectively. The combination therapy revealed more frequent leukopenia and nausea/vomiting than radiation alone group, but degree of side effects was only mild to moderate. Conclusion : The combined external radiotherapy and chemotherapy for advanced esophageal cancer appears to improve the response rate, local control rate and survival rate, but the improvement was not statistically significant. The side effects of combined modalities were mild to moderate without significant morbidity. Therefore it may be worthwhile to continue the present combined external radiotherapy and chemotherapy in the management of advanced esophageal cancer to confirm our result.

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An Analysis of the Moderating Effects of User Ability on the Acceptance of an Internet Shopping Mall (인터넷 쇼핑몰 수용에 있어 사용자 능력의 조절효과 분석)

  • Suh, Kun-Soo
    • Asia pacific journal of information systems
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    • v.18 no.4
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    • pp.27-55
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    • 2008
  • Due to the increasing and intensifying competition in the Internet shopping market, it has been recognized as very important to develop an effective policy and strategy for acquiring loyal customers. For this reason, web site designers need to know if a new Internet shopping mall(ISM) will be accepted. Researchers have been working on identifying factors for explaining and predicting user acceptance of an ISM. Some studies, however, revealed inconsistent findings on the antecedents of user acceptance of a website. Lack of consideration for individual differences in user ability is believed to be one of the key reasons for the mixed findings. The elaboration likelihood model (ELM) and several studies have suggested that individual differences in ability plays an moderating role on the relationship between the antecedents and user acceptance. Despite the critical role of user ability, little research has examined the role of user ability in the Internet shopping mall context. The purpose of this study is to develop a user acceptance model that consider the moderating role of user ability in the context of Internet shopping. This study was initiated to see the ability of the technology acceptance model(TAM) to explain the acceptance of a specific ISM. According to TAM. which is one of the most influential models for explaining user acceptance of IT, an intention to use IT is determined by usefulness and ease of use. Given that interaction between user and website takes place through web interface, the decisions to accept and continue using an ISM depend on these beliefs. However, TAM neglects to consider the fact that many users would not stick to an ISM until they trust it although they may think it useful and easy to use. The importance of trust for user acceptance of ISM has been raised by the relational views. The relational view emphasizes the trust-building process between the user and ISM, and user's trust on the website is a major determinant of user acceptance. The proposed model extends and integrates the TAM and relational views on user acceptance of ISM by incorporating usefulness, ease of use, and trust. User acceptance is defined as a user's intention to reuse a specific ISM. And user ability is introduced into the model as moderating variable. Here, the user ability is defined as a degree of experiences, knowledge and skills regarding Internet shopping sites. The research model proposes that the ease of use, usefulness and trust of ISM are key determinants of user acceptance. In addition, this paper hypothesizes that the effects of the antecedents(i.e., ease of use, usefulness, and trust) on user acceptance may differ among users. In particular, this paper proposes a moderating effect of a user's ability on the relationship between antecedents with user's intention to reuse. The research model with eleven hypotheses was derived and tested through a survey that involved 470 university students. For each research variable, this paper used measurement items recognized for reliability and widely used in previous research. We slightly modified some items proper to the research context. The reliability and validity of the research variables were tested using the Crobnach's alpha and internal consistency reliability (ICR) values, standard factor loadings of the confirmative factor analysis, and average variance extracted (AVE) values. A LISREL method was used to test the suitability of the research model and its relating six hypotheses. Key findings of the results are summarized in the following. First, TAM's two constructs, ease of use and usefulness directly affect user acceptance. In addition, ease of use indirectly influences user acceptance by affecting trust. This implies that users tend to trust a shopping site and visit repeatedly when they perceive a specific ISM easy to use. Accordingly, designing a shopping site that allows users to navigate with heuristic and minimal clicks for finding information and products within the site is important for improving the site's trust and acceptance. Usefulness, however, was not found to influence trust. Second, among the three belief constructs(ease of use, usefulness, and trust), trust was empirically supported as the most important determinants of user acceptance. This implies that users require trustworthiness from an Internet shopping site to be repeat visitors of an ISM. Providing a sense of safety and eliminating the anxiety of online shoppers in relation to privacy, security, delivery, and product returns are critically important conditions for acquiring repeat visitors. Hence, in addition to usefulness and ease of use as in TAM, trust should be a fundamental determinants of user acceptance in the context of internet shopping. Third, the user's ability on using an Internet shopping site played a moderating role. For users with low ability, ease of use was found to be a more important factors in deciding to reuse the shopping mall, whereas usefulness and trust had more effects on users with high ability. Applying the EML theory to these findings, we can suggest that experienced and knowledgeable ISM users tend to elaborate on such usefulness aspects as efficient and effective shopping performance and trust factors as ability, benevolence, integrity, and predictability of a shopping site before they become repeat visitors of the site. In contrast, novice users tend to rely on the low elaborating features, such as the perceived ease of use. The existence of moderating effects suggests the fact that different individuals evaluate an ISM from different perspectives. The expert users are more interested in the outcome of the visit(usefulness) and trustworthiness(trust) than those novice visitors. The latter evaluate the ISM in a more superficial manner focusing on the novelty of the site and on other instrumental beliefs(ease of use). This is consistent with the insights proposed by the Heuristic-Systematic model. According to the Heuristic-Systematic model. a users act on the principle of minimum effort. Thus, the user considers an ISM heuristically, focusing on those aspects that are easy to process and evaluate(ease of use). When the user has sufficient experience and skills, the user will change to systematic processing, where they will evaluate more complex aspects of the site(its usefulness and trustworthiness). This implies that an ISM has to provide a minimum level of ease of use to make it possible for a user to evaluate its usefulness and trustworthiness. Ease of use is a necessary but not sufficient condition for the acceptance and use of an ISM. Overall, the empirical results generally support the proposed model and identify the moderating effect of the effects of user ability. More detailed interpretations and implications of the findings are discussed. The limitations of this study are also discussed to provide directions for future research.

How Enduring Product Involvement and Perceived Risk Affect Consumers' Online Merchant Selection Process: The 'Required Trust Level' Perspective (지속적 관여도 및 인지된 위험이 소비자의 온라인 상인선택 프로세스에 미치는 영향에 관한 연구: 요구신뢰 수준 개념을 중심으로)

  • Hong, Il-Yoo B.;Lee, Jung-Min;Cho, Hwi-Hyung
    • Asia pacific journal of information systems
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    • v.22 no.1
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    • pp.29-52
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    • 2012
  • Consumers differ in the way they make a purchase. An audio mania would willingly make a bold, yet serious, decision to buy a top-of-the-line home theater system, while he is not interested in replacing his two-decade-old shabby car. On the contrary, an automobile enthusiast wouldn't mind spending forty thousand dollars to buy a new Jaguar convertible, yet cares little about his junky component system. It is product involvement that helps us explain such differences among individuals in the purchase style. Product involvement refers to the extent to which a product is perceived to be important to a consumer (Zaichkowsky, 2001). Product involvement is an important factor that strongly influences consumer's purchase decision-making process, and thus has been of prime interest to consumer behavior researchers. Furthermore, researchers found that involvement is closely related to perceived risk (Dholakia, 2001). While abundant research exists addressing how product involvement relates to overall perceived risk, little attention has been paid to the relationship between involvement and different types of perceived risk in an electronic commerce setting. Given that perceived risk can be a substantial barrier to the online purchase (Jarvenpaa, 2000), research addressing such an issue will offer useful implications on what specific types of perceived risk an online firm should focus on mitigating if it is to increase sales to a fullest potential. Meanwhile, past research has focused on such consumer responses as information search and dissemination as a consequence of involvement, neglecting other behavioral responses like online merchant selection. For one example, will a consumer seriously considering the purchase of a pricey Guzzi bag perceive a great degree of risk associated with online buying and therefore choose to buy it from a digital storefront rather than from an online marketplace to mitigate risk? Will a consumer require greater trust on the part of the online merchant when the perceived risk of online buying is rather high? We intend to find answers to these research questions through an empirical study. This paper explores the impact of enduring product involvement and perceived risks on required trust level, and further on online merchant choice. For the purpose of the research, five types or components of perceived risk are taken into consideration, including financial, performance, delivery, psychological, and social risks. A research model has been built around the constructs under consideration, and 12 hypotheses have been developed based on the research model to examine the relationships between enduring involvement and five components of perceived risk, between five components of perceived risk and required trust level, between enduring involvement and required trust level, and finally between required trust level and preference toward an e-tailer. To attain our research objectives, we conducted an empirical analysis consisting of two phases of data collection: a pilot test and main survey. The pilot test was conducted using 25 college students to ensure that the questionnaire items are clear and straightforward. Then the main survey was conducted using 295 college students at a major university for nine days between December 13, 2010 and December 21, 2010. The measures employed to test the model included eight constructs: (1) enduring involvement, (2) financial risk, (3) performance risk, (4) delivery risk, (5) psychological risk, (6) social risk, (7) required trust level, (8) preference toward an e-tailer. The statistical package, SPSS 17.0, was used to test the internal consistency among the items within the individual measures. Based on the Cronbach's ${\alpha}$ coefficients of the individual measure, the reliability of all the variables is supported. Meanwhile, the Amos 18.0 package was employed to perform a confirmatory factor analysis designed to assess the unidimensionality of the measures. The goodness of fit for the measurement model was satisfied. Unidimensionality was tested using convergent, discriminant, and nomological validity. The statistical evidences proved that the three types of validity were all satisfied. Now the structured equation modeling technique was used to analyze the individual paths along the relationships among the research constructs. The results indicated that enduring involvement has significant positive relationships with all the five components of perceived risk, while only performance risk is significantly related to trust level required by consumers for purchase. It can be inferred from the findings that product performance problems are mostly likely to occur when a merchant behaves in an opportunistic manner. Positive relationships were also found between involvement and required trust level and between required trust level and online merchant choice. Enduring involvement is concerned with the pleasure a consumer derives from a product class and/or with the desire for knowledge for the product class, and thus is likely to motivate the consumer to look for ways of mitigating perceived risk by requiring a higher level of trust on the part of the online merchant. Likewise, a consumer requiring a high level of trust on the merchant will choose a digital storefront rather than an e-marketplace, since a digital storefront is believed to be trustworthier than an e-marketplace, as it fulfills orders by itself rather than acting as an intermediary. The findings of the present research provide both academic and practical implications. The first academic implication is that enduring product involvement is a strong motivator of consumer responses, especially the selection of a merchant, in the context of electronic shopping. Secondly, academicians are advised to pay attention to the finding that an individual component or type of perceived risk can be used as an important research construct, since it would allow one to pinpoint the specific types of risk that are influenced by antecedents or that influence consequents. Meanwhile, our research provides implications useful for online merchants (both online storefronts and e-marketplaces). Merchants may develop strategies to attract consumers by managing perceived performance risk involved in purchase decisions, since it was found to have significant positive relationship with the level of trust required by a consumer on the part of the merchant. One way to manage performance risk would be to thoroughly examine the product before shipping to ensure that it has no deficiencies or flaws. Secondly, digital storefronts are advised to focus on symbolic goods (e.g., cars, cell phones, fashion outfits, and handbags) in which consumers are relatively more involved than others, whereas e- marketplaces should put their emphasis on non-symbolic goods (e.g., drinks, books, MP3 players, and bike accessories).

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Analysis of Neurological Complications on Antegrade Versus Retrograde Cerebral Perfusion in the Surgical Treatment of Aortic Dissection (대동맥 박리에서 전방성 뇌 관류와 역행성 뇌 관류의 신경학적 분석)

  • Park Il;Kim Kyu Tae;Lee Jong Tae;Chang Bong Hyun;Lee Eung Bae;Cho Joon Yong
    • Journal of Chest Surgery
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    • v.38 no.7 s.252
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    • pp.489-495
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    • 2005
  • In the surgical treatment of aortic dissection, aortic arch replacement under total circulatory arrest is often performed after careful inspection to determine the severity of disease progression. Under circulatory arrest, antegrade or retrograde cerebral perfusion is required for brain protection. Recently, antegrade cerebral perfusion has been used more, because of the limitation of retrograde cerebral perfusion. This study is to compare these two methods especially in the respect to neurological complications. Material and Method: Forty patients with aortic dissection involving aortic arch from May 2000 to May 2004 were enrolled in this study, and the methods of operation, clinical recovery, and neurological complications were retrospectively reviewed. Result: In the ACP (antegrade cerebral perfusion) group, axillary artery cannulation was performed in 10 out of 15 cases. In the RCP (retrograde cerebral perfusion) group, femoral artery Cannulation was performed in 24 out of 25 cases. The average esophageal and rectal temperature under total circulatory arrest was $17.2^{\circ}C\;and\;22.8^{\circ}C$ in the group A, and $16.0^{\circ}C\;and\;19.7^{\circ}C$ in the group B, respectively. Higher temperature in the ACP group may have brought the shorter operation and cardiopulmonary bypass time. However, the length of period for postoperative clinical recovery and admission duration did not show any statistically significant differences. Eleven out of the total 15 cases in the ACP group and thirteen out of the total 25 cases in the RCP group showed neurological complication but did not show statistically significant difference. In each group, there were 5 cases with permanent neurological complications. All 5 cases in the ACP group showed some improvements that enabled routine exercise. However all 5 cases in RCP group did not show significant improvements. Conclusion: The Antegrade, cerebral perfusion, which maintains orthordromic circulation, brings moderate degree of hypothermia and, therefore, shortens the operation time and cardiopulmonary bypass time. We concluded that Antegrade cerebral perfusion is safe and can be used widely under total circulatory arrest.

The Comparision of Right Anterolateral Thoracotomy and Median Sternotomy in the Atrial Septal Defect Repair. (심방중격결손증 수술에서 우전측부개흉술과 정중흉골절개술의 비교)

  • Kim, Hyuck;Kim, Sang-Heon;Kim, Young-Hak;Chung, Won-Sang;Kang, Jung-Ho;Lee, Chul-Beom;Jee, Heng-Ok;Kim, Nam-Soo;Kim, Kyung-Soo
    • Journal of Chest Surgery
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    • v.36 no.1
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    • pp.1-6
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    • 2003
  • Currently, atrial septal defect repair has been considered low risk operation duo to the development of open heart surgery Not only the operation itself, but also the cosmetic aspect is now focused. Though many methods exist as minimally invasive cardiac surgery in atrial septal defect repair, some surgeons advocate that right anterolateral thoracotomy is better than the others in the cosmetic aspect and we compared right anterolateral thoracotomy with median sternotomy. Material and Method: From January 1999 to August 2002, 43 patient underwent atrial septal defect repair by one operator, including 15 patients through right anterolateral thoracotomy(group A) and 15 patients through median sternotomy(group B) in Hanyang university Hospital. The data were randomized and operation outcomes were analyzed between these two groups. Result: The mean weight of group A was 38.77$\pm$15.57kg and 38.21$\pm$21.82kg in group B. In group A, mean operation (OP) time was 197.6$\pm$61.40min, mean cardiopulmonary bypass(CPB) time was 48.66$\pm$13.02min and mean fibrillation time or aortic cross clamp(ACC) time was 30$\pm$11.64min. In group B, mean OP time was 212.33$\pm$31.95min, mean CPB time was 55$\pm$12.10min, and mean fibrillation or ACC time was 29.33$\pm$9.04min. There was no significant differences in these two groups. In group A, mean mechanical ventilation time was 3.78$\pm$0.78 hours, mean postoperative ICU stay was 1.2$\pm$0.47 days and mean postoperative hospital stay was 10.20 41.08 days. In group B, mean mechanical ventilation time was 5.95$\pm$3.73 hours, mean post operative ICU stay was 1.41$\pm$0.61 days, and mean postoperative hospital stay was 12.20$\pm$3.55 days. There was no any significant difference in two groups. Group A had significantly lower mean thoracic and pleuropericardial drainage than group B (175.33$\pm$90.54cc vs 352.33$\pm$239.43cc, p<0.05). Complication was seen in one case in group B, transient 2nd degree A-V block. Conclusion: Right anterolateral thoracotomy was better than median sternotomy not only in cosmetic aspect but also in postoperative thoracic and pleuropericardial drainage, using the same instrument(p.0.05). But, right anterolateral thoracotomy was more technically difficult due to narrow operative field and we should be careful of aortic cannulation.

Synthesis and Preliminary Evaluation of $9-(4-[^{18}F]Fluoro-3-hydroxymethylbutyl)$ Guanine $([^{18}F]FHBG)$ in HSV1-tk Gene Transduced Hepatoma Cell (9-(4-$[^{18}F]Fluoro-3-hydroxymethylbutyl)$guanine $([^{18}F]FHBG)$의 합성과 헤르페스 단순 바이러스 티미딘 키나아제 이입 간암 세포주에서의 기초 연구)

  • Moon, Byung-Seok;Lee, Tae-Sup;Lee, Myoung-Keun;Lee, Kyo-Chul;An, Gwang-Il;Chun, Kwon-Soo;Awh, Ok-Doo;Chi, Dae-Yoon;Choi, Chang-Woon;Lim, Sang-Moo;Cheon, Gi-Jeong
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.4
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    • pp.218-227
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    • 2006
  • Purpose: The HSV1-tk reporter gene system is the most widely used system because of its advantage that direct monitoring is possible without the introduction of a separate reporter gene in case of HSV1-tk suicide gene therapy. In this study, we investigate the usefulness of the reporter probe (substrate), $9-(4-[^{18}F]Fluoro-3-hydroxymethylbutyl)$guanine ($[^{18}F]FHBG$) for non-invasive reporter gene imaging using PET in HSV1-tk expressing hepatoma model. Materials and Methods: Radiolabeled FHBG was prepared in 8 steps from a commercially available triester. The labeling reaction was carried out by NCA nucleophilic substitution with $K[^{18}F]/K2.2.2.$ in acetonitrile using N2-monomethoxytrityl-9-14-(tosyl)-3-monomethoxytritylmethylbutyl]guanine as a precursor, followed by deprotection with 1 N HCl. Preliminary biological properties of the probe were evaluated with MCA cells and MCA-tk cells transduced with HSV1-tk reporter gene. In vitro uptake and release-out studies of $[^{18}F]FHBG$ were performed, and was analyzed correlation between $[^{18}F]FHBG$ uptake ratio according to increasing numeric count of MCA-tk cells and degree of gene expression. MicroPET scan image was obtained with MCA and MCA-tk tumor bearing Balb/c-nude mouse model. Results: $[^{18}F]FHBG$ was purified by reverse phase semi-HPLC system and collected at around 16-18 min. Radiothemical yield was about 20-25%) (corrected for decay), radiochemical purity was >95% and specific activity was around >55.5 $GBq/{\mu}\;mol$. Specific accumulation of $[^{18}F]FHBG$ was observed in HSV1-tk gene transduced MCA-tk cells but not in MCA cells, and consecutive 1 hour release-out results showed more than 86% of uptaked $[^{18}F]FHBG$ was retained inside of cells. The uptake of $[^{18}F]FHBG$ was showed a highly significant linear correlation ($R^2=0.995$) with increasing percentage of MCA-tk numeric cell count. In microPET scan images, remarkable difference of accumulation was observed for the two type of tumors. Conclusion: $[^{18}F]FHBG$ appears to be a useful as non-invasive PET imaging substrate in HSV1-tk expressing hepatoma model.

The study of food habit and degree of depression in nursing home and privite home living elderly (시설노인과 재가노인의 식습관과 정신건강 상태에 관한 실태조사)

  • Han, Myung-Joo;Koo, Sung-Ja;Lee, Young-Soon
    • Journal of the Korean Society of Food Culture
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    • v.13 no.5
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    • pp.475-486
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    • 1998
  • The dietary habit, health condition and the cognition concerning the health food have been surveyed with the help of the 151 old people living in In-Cheon and Seoul. In this study, the old are classified as an institution for the aged and the old in their own home. The preference and mental health condition influenced on dietary habits have been surveyed as wall. Their dietary habits such s three meals a day and a regular meal time have show) that they have generally good eating habits. Psychologically, the old in an institution for the aged think their health condition is not so good in comparison with the old in their own home. The old in their own home have good condition in that they can go up the stairs, exercise often and walk relatively well. Moreover, men's health condition is better than women. The old generally like meats(especially beef) and prefer sesame oil, perilla oil, soy been oil to Western oil. They like sweat flavor the most and hot, salty taste in order. Thier favorite cooking method is a pot stew, soup and season. The difference between dietary habit and mental health based on an academic career, an allowance and a residential condition shows that the old who live alon have relatively terrible eating habit and the more learned, the better. The more pocket money they have, the better dietary habits they have. The old feel glommy in general and the old in an institution are more depressed and it is statistically significant.

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The Analysis of Dose in a Rectum by Multipurpose Brachytherapy Phantom (근접방사선치료용 다목적 팬톰을 이용한 직장 내 선량분석)

  • Huh, Hyun-Do;Kim, Seong-Hoon;Cho, Sam-Ju;Lee, Suk;Shin, Dong-Oh;Kwon, Soo-Il;Kim, Hun-Jung;Kim, Woo-Chul;K. Loh John-J.
    • Radiation Oncology Journal
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    • v.23 no.4
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    • pp.223-229
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    • 2005
  • Purpose: In this work we designed and made MPBP(Multi Purpose Brachytherapy Phantom). The MPBP enables one to reproduce the same patient set-up in MPBP as the treatment of the patient and we tried to get an exact analysis of rectal doses in the phantom without need of in-vivo dosimetry. Materials and Methods: Dose measurements were tried at a point of rectum 1, the reference point of rectum, with a diode detector for 4 patients treated with tandem and ovoid for a brachytherapy of a cervix cancer. Total 20 times of rectal dose measurements were made with 5 times a patient. The set-up variation of the diode detector was analyzed. The same patient set-ups were reproduced in self-made MPBP and then rectal doses were measured with TLD. Results: The measurement results of the diode detector showed that the set-up variation of the diode detector was the maximum $11.25{\pm}0.95mm$ in the y-direction for Patient 1 and the maximum $9.90{\pm}4.50mm,\;20.85{\pm}4.50mm,\;and\;19.15{\pm}3.33mm$ in the z-direction for Patient 2, 3, and 4, respectively. Un analyzing the degree of variation in 3 directions the more variation was showed in the z-direction than x- and y-direction except Patient 1. The results of TLD measurements in MPBP showed the relative maximum error of 8.6% and 7.7% at a point of rectum 1 for Patient 1 and 4, respectively and 1.7% and 1.2% for Patient 2 and 3, respectively. The doses measured at R1 and R2 were higher than those calculated except R point of Patient 2. this can be thought to related to the algorithm of dose calculation, whcih corrects for air and water but is guessed not to consider the correction for the scattered rays, but by considering the self-error (${\pm}5%$) TLD has the relative error of values measured and calculated was analyzed to be in a good agreement within 15%. Conclusion: The reproducibility of dose measurements under the same condition as the treatment could be achieved owing to the self-made MPMP and the dose at the point of interest could be analyzed accurately. If a treatment is peformed after achieving dose optimization using the data obtained in the phantom, dose will be able to be minimized to important organs.