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A Study on the Countermeasures Taken By the Korean Healthcare and Life Sciences Industry Regarding U.S. Import Refusals: Focus on the Analysis of FDA Violation Codes (한국 바이오헬스 산업의 미국 수입거부 대응 방안 연구 : FDA 위반코드 분석을 중심으로)

  • Yu-Han Lee;Hag-Min Kim
    • Korea Trade Review
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    • v.48 no.3
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    • pp.131-150
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    • 2023
  • The purpose of this study was to find a countermeasure to the U.S. import refusals for the Korean healthcare and life sciences industry. To this end, an analysis of trends during the pandemic was conducted using the KITA Border Rejection Database, which includes information on items and types of import refusals. The reason for rejection was also analyzed according to the FDA violation codes. The degree of countermeasure for import refusals was identified by measuring the unit rejection rate (URR). The results of the analysis showed that the major U.S. import refusals for the Korean healthcare and life sciences industry had expanded from contact lenses to COVID-19 diagnostic kits and drugs after the pandemic broke out. The major reasons for import refusals were non-compliance with the Predicate Device and Drugs Act and non-approval by the FDA for products and facilities. On the other hand, the unit rejection rate (URR) of major items in the Korean healthcare and life sciences industry was measured higher than the industry average. The results therefore showed a low level of response to U.S. import refusals. The results of the analysis of reasons for import refusals by item according to FDA violation codes were as follows. First of all, the main violation for contact lenses and COVID-19 diagnostic kits corresponded to misbranding. This was often due to the fact that Korean companies did not provide the relevant notices and information required by the FDA. Many cases also failed to demonstrate a substantial equivalency compared to predicate devices already on the market. On the other hand, applications for new unapproved drugs were not accepted as they had yet to pass relevant regulations that would prove their safety and efficacy. In conclusion, import refusals for the Korean healthcare and life sciences industry were found to be closely related to technical barriers to trade (TBT).

A Study on the Improvement of the Employee Stock Ownership Plans (우리사주제의 개선에 대한 연구)

  • Kwon, Yong-man;Shin, Won-chul
    • Journal of Venture Innovation
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    • v.3 no.2
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    • pp.95-109
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    • 2020
  • The source of value-added creation in modern times has been transformed from material to man's value-added generating power, and ownership of the means of production has been converted from a particular landlord, capitalist to a person with value-added capacity, and a system of capital participation is needed beyond the profit-sharing system or performance incentive system in which workers of an enterprise participate in simple profits if they significantly increase the added value of the company. It is also necessary to introduce our private stock system as a means of addressing the problem of capital bias and for the stable development of capitalism. The purpose of Employee Stock Ownership Plans is to improve the economic and social status of workers and promote labor-management cooperation by allowing workers to acquire and hold shares of the stock company in which the employee ownership association is established through the employee ownership association, but the reality is that our stock ownership system has failed to achieve its purpose due to insufficient protection against the employee. In terms of welfare, the acquisition of our company shares should include active government support for the welfare of workers' ownership on a social welfare level rather than on the logic of the capital market, and in terms of investment, it would not be appropriate to apply the regulation for investor protection to see workers' acquisition of our company shares as 'investment' in the view of workers' willingness to own shares on the stock market. Therefore, as a way to support and deregulate employee's stock acquisition, 1. Expanding direct support, such as tax support, 2. As employee's stock ownership association is being discussed as a division's nature, it is less effective in terms of various management, not investment, and 3. Those who own stocks with 1% of the company's shares and 300 million won in face value will be classified as major shareholders. As a way to reduce the risk of management of our company owners and cooperative funds, As a measure to reduce the risk of management of our company owners and cooperative funds, only our employee shareholders' association shall manage the fund in a long-term deposit, and even though our employee's stock is managed by the association or company after the end of the deposit period, the management of each employee shall be allowed and In terms of improving the utilization of our company's stock and fund, 1. Employee's stockholders are prohibited from lending during the deposit period, but it is necessary to improve profitability by allowing them to borrow under strict restrictions, 2. It is necessary to make the use of the employee's welfare funds available for the preservation of losses, and to stipulate the redemption obligations of unlisted companies in order to improve the redemption system of our company.

Empirical Analysis of Accelerator Investment Determinants Based on Business Model Innovation Framework (비즈니스 모델 혁신 프레임워크 기반의 액셀러레이터 투자결정요인 실증 분석)

  • Jung, Mun-Su;Kim, Eun-Hee
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.1
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    • pp.253-270
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    • 2023
  • Research on investment determinants of accelerators, which are attracting attention by greatly improving the survival rate of startups by providing professional incubation and investment to startups at the same time, is gradually expanding. However, previous studies do not have a theoretical basis in developing investment determinants in the early stages, and they use factors of angel investors or venture capital, which are similar investors, and are still in the stage of analyzing importance and priority through empirical research. Therefore, this study verified for the first time in Korea the discrimination and effectiveness of investment determinants using accelerator investment determinants developed based on the business model innovation framework in previous studies. To this end, we first set the criteria for success and failure of startup investment based on scale-up theory and conducted a survey of 22 investment experts from 14 accelerators in Korea, and secured valid data on a total of 97 startups, including 52 successful scale-up startups and 45 failed scale-up startups, were obtained and an independent sample t-test was conducted to verify the mean difference between these two groups by accelerator investment determinants. As a result of the analysis, it was confirmed that the investment determinants of accelerators based on business model innovation framework have considerable discrimination in finding successful startups and making investment decisions. In addition, as a result of analyzing manufacturing-related startups and service-related startups considering the characteristics of innovation by industry, manufacturing-related startups differed in business model, strategy, and dynamic capability factors, while service-related startups differed in dynamic capabilities. This study has great academic implications in that it verified the practical effectiveness of accelerator investment determinants derived based on business model innovation framework for the first time in Korea, and it has high practical value in that it can make effective investments by providing theoretical grounds and detailed information for investment decisions.

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From a Defecation Alert System to a Smart Bottle: Understanding Lean Startup Methodology from the Case of Startup "L" (배변알리미에서 스마트바틀 출시까지: 스타트업 L사 사례로 본 린 스타트업 실천방안)

  • Sunkyung Park;Ju-Young Park
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.5
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    • pp.91-107
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    • 2023
  • Lean startup is a concept that combines the words "lean," meaning an efficient way of running a business, and "startup," meaning a new business. It is often cited as a strategy for minimizing failure in early-stage businesses, especially in software-based startups. By scrutinizing the case of a startup L, this study suggests that lean startup methodology(LSM) can be useful for hardware and manufacturing companies and identifies ways for early startups to successfully implement LSM. To this end, the study explained the core of LSM including the concepts of hypothesis-driven approach, BML feedback loop, minimum viable product(MVP), and pivot. Five criteria to evaluate the successful implementation of LSM were derived from the core concepts and applied to evaluate the case of startup L . The early startup L pivoted its main business model from defecation alert system for patients with limited mobility to one for infants or toddlers, and finally to a smart bottle for infants. In developing the former two products, analyzed from LSM's perspective, company L neither established a specific customer value proposition for its startup idea and nor verified it through MVP experiment, thus failed to create a BML feedback loop. However, through two rounds of pivots, startup L discovered new target customers and customer needs, and was able to establish a successful business model by repeatedly experimenting with MVPs with minimal effort and time. In other words, Company L's case shows that it is essential to go through the customer-market validation stage at the beginning of the business, and that it should be done through an MVP method that does not waste the startup's time and resources. It also shows that it is necessary to abandon and pivot a product or service that customers do not want, even if it is technically superior and functionally complete. Lastly, the study proves that the lean startup methodology is not limited to the software industry, but can also be applied to technology-based hardware industry. The findings of this study can be used as guidelines and methodologies for early-stage companies to minimize failures and to accelerate the process of establishing a business model, scaling up, and going global.

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Text Mining-Based Emerging Trend Analysis for e-Learning Contents Targeting for CEO (텍스트마이닝을 통한 최고경영자 대상 이러닝 콘텐츠 트렌드 분석)

  • Kyung-Hoon Kim;Myungsin Chae;Byungtae Lee
    • Information Systems Review
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    • v.19 no.2
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    • pp.1-19
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    • 2017
  • Original scripts of e-learning lectures for the CEOs of corporation S were analyzed using topic analysis, which is a text mining method. Twenty-two topics were extracted based on the keywords chosen from five-year records that ranged from 2011 to 2015. Research analysis was then conducted on various issues. Promising topics were selected through evaluation and element analysis of the members of each topic. In management and economics, members demonstrated high satisfaction and interest toward topics in marketing strategy, human resource management, and communication. Philosophy, history of war, and history demonstrated high interest and satisfaction in the field of humanities, whereas mind health showed high interest and satisfaction in the field of in lifestyle. Studies were also conducted to identify topics on the proportion of content, but these studies failed to increase member satisfaction. In the field of IT, educational content responds sensitively to change of the times, but it may not increase the interest and satisfaction of members. The present study found that content production for CEOs should draw out deep implications for value innovation through technology application instead of simply ending the technical aspect of information delivery. Previous studies classified contents superficially based on the name of content program when analyzing the status of content operation. However, text mining can derive deep content and subject classification based on the contents of unstructured data script. This approach can examine current shortages and necessary fields if the service contents of the themes are displayed by year. This study was based on data obtained from influential e-learning companies in Korea. Obtaining practical results was difficult because data were not acquired from portal sites or social networking service. The content of e-learning trends of CEOs were analyzed. Data analysis was also conducted on the intellectual interests of CEOs in each field.

Studies on the Germination Characteristics of Sesame (Sesamum indicum L.) (참깨의 발아특성(發芽特性)에 관(關)한 연구(硏究))

  • Kim, Choong Soo
    • Korean Journal of Agricultural Science
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    • v.10 no.1
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    • pp.28-60
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    • 1983
  • This study was carried out to define the effects of external factors including temperature, moisture, oxygen and light quality on the germination of sesame seeds and to investigate the change of major chemical constituents of seeds during germination. The results obtained are summarized as follows: 1. The average germination ratio was from 95.8% to 97.2% when it was tested every $5^{\circ}C$ intervals from $20^{\circ}C$ to $35^{\circ}C$ and no significant difference in germination ratio was found within $20^{\circ}C$ to $35^{\circ}C$. But the germination ratio dropped rapidly to 32.2% when seeds were germinated at $15^{\circ}C$ and the coefficient of variation become greater(77%) 2. The days required for germination ranged from 1.16 to 1. 64 at the temperatures of $35^{\circ}C$ to $25^{\circ}C$ and they were 3.07 and 10.4 at the temperatures of $20^{\circ}C$ and $15^{\circ}C$, respectively. 3. Considering the germination ratio and days needed, $15^{\circ}C$ was assumed to be the minimum temperature for germination practically and this temperature is recommended for testing low temperature tolerance of seed germination of sesame cultivars. 4. The varieties shown the highest low temperature tolerance were Shirogoma and Turkey. The next varieties shown some degree of low temperature germination were Suweon #29, Naebok and IS 58. The varieties with 70 to 80% of germination ratio were Maepo, Suweon #14, Kimpo, Moondeok, and Haenam. Among the 90 varieties tested, the varieties with comparatively high degree of low temperature tolerance were about 10%, and 70% of the low temperature tolerant varieties were domestic varieties. 5. At $12^{\circ}C$ the Shirogoma was the only variety which showed over 50% of germination ratio, 71.4% of the varieties showed less than 20% of germination ratio. When the temperature was raised to $27^{\circ}C$ 18 days after placement at $12^{\circ}C$ all the varieties showed over 90% of germination ratio within 2days. 6. The amounts of water imbibition needed for seed germination were 0.48 to 0.62 times of the seed dry weight at $25^{\circ}C$ and were significantly different among sesame cultivars. About 63% of water required for germination was imbibed in 2 hours after placement of seeds under the germination condition. 7. Under saturated moisture condition the average germination ratio was 0.42%. In the soil of which water potential was -0.4bar 64.8% of the seeds germinated and the most adequate soil water potential for sesame seed germination was about -0.4 to -5.5 bar. The germination ratio decreased as the soil water potential declined below -5.5 bar. 8. Six out of 10 varieties were not influenced by 5% of oxygen in air germination chamber, while varieties such as Yecheon, PI 158073, IS 103 and Euisangcheon showed 64 to 91% of germination under the 5% oxygen content. Under anaerobic condition, cotyledones were not emerged but only hypocotyl was emerged and elongated. The germination ratio of IS 103 decreased significantly under anaerobic condition. 9. When the seeds were dried for 24 hours after 12 hours imbibition of water, the seeds of Cheongsong did not lose their germination ability and 27.5% was germinated but Suweon #9 and Early Russian failed to germinate. However, the germination ratio of IS 103 decreased when the seed were dried 24 hours after 4 hours imbibition of water and the germination ability of IS 103 was maintained even though the seeds were dried for 24 hours after 24 hours imbibition of water. 10. During germination, sugar content of sesame seed increased rapidly and activity of ${\alpha}$-amylase increased gradually while starch content decreased significantly. The rates of increase in sugar content and enzyme activity and decrease in starch content were significantly lower at $15^{\circ}C$ compared with those at $25^{\circ}C$. 11. During germination of sesame seeds, lipid content in the seeds dropped rapidly and the activity of alkaline lipase increased significantly at early stage of germination. The rate of decrease in lipid content and increase in emzyme activity was lower at $15^{\circ}C$ than at $25^{\circ}C$. 12. Four out of 6 varieties were not affected in germination by light wave length. But Suweon #8 was inhibited in germination by 600-650nm. and IS 103 by 600 to 650nm and 500 to 550nm of light wave length. Suweon #8 showed high germination ratio under 650 to 760 nm and 500 to 560nm, and IS 103 under 400 to 470nm and complete darkness. 13. The germination ratios increased significantly in the seeds of which 1000 grain weight is heavier. When the seeds were placed at soil 4cm deep, Cheongsong and Early Russian failed to emerge their cotyledones, but Suweon #9 and IS 103 showed 32.5 and 50% cotyledone emergence, respectively. The extracts from sesame plant and soil where the sesame was cultivated previously did not affect in the-germination of sesame seeds. 14. The covering by black or transparent polyethylene films increased germination ratio compared with uncovered seeds. The covering was effective in shortening the days needed for germination and in improving the early seedling growth, number of capsules per plant and grain yield. Difference was not so seizable between the two polyethylene films but the transparent film appeared somewhat more effective than the black one. 15. Simcheon, Cheongsong. Suweon #9. PI 158073 and IS 103 showed lower rate of water absorbtion by seed during germination and Suweon #8, Suweon #26, Orotall and Euisangcheon showed high increase in seed weight after water absorbtion by seed.

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The Effect of the Gap between College Students' Perception of the Importance of Coffee Shops and Their Satisfaction after Patronizing Coffee Shops on Their Purchasing Behavior (대전원교학생대가배점중요성적감지화타문광고가배점지후적만의도지간적차거대타문구매행위적영향(大专院校学生对咖啡店重要性的感知和他们光顾咖啡店之后的满意度之间的差距对他们购买行为的影响))

  • Lee, Won-Ok
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.4
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    • pp.1-10
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    • 2009
  • The purpose of this study was to categorize the gap between coffee shop 'importance' (as perceived by customers before patronizing the coffee shop) and 'satisfaction' (perception of customers after patronizing the coffee shop) as positive or negative and to analyze the effect of these gaps on purchasing behavior. To do this, I used the gap between importance and satisfaction regarding the choice of a coffee shop as the explanatory variable and performed an empirical analysis of the direction and size of the effect of the gap on purchasing behavior (overall satisfaction, willingness-to-revisit) by applying the Ordered Probit Model (OPM). A previous study that used IPA to evaluate the effects of gaps estimated the direction and size of a quadrant but failed to analyze the effect of gaps on customers. In this study, I evaluated the effects of positive and negative gaps on customer satisfaction and willingness-to-revisit. Using OPM, I quantified the effect of positive and negative gaps on overall customer satisfaction and willingness-to-revisit. Per-head expenditure, frequency of visits, and coffee-purchasing place had the most positive effects on overall customer satisfaction. Frequency of visits, followed by per-head expenditure and then coffee-purchasing place, had the most positive impact on willingness-to-visit. Thus per-head expenditure and frequency of visits had the greatest positive effects on overall satisfaction and willingness-to-revisit. This finding implies that the higher the actual satisfaction (gap) of customers who spend KRW5,000 or more once or more per week at coffee shops is, the higher their overall satisfaction and willingness-to-revisit are. Despite the fact that economical efficiency had a significant effect on overall satisfaction and willingness-to-revisit, college and university students still use coffee shops and are willing to spend KRW5,000 because they do not only purchase coffee as a product itself, but use the coffee shop for other activities, such as working, meeting friends, or relaxing. College and university students also access the Internet in coffee shops via personal laptops, watch movies, and study; thus, coffee shops should provide their customers with the appropriate facilities and services. The fact that a positive gap for coffee shop brand had a positive effect on willingness-to-revisit implies that the higher the level of customer satisfaction, the greater the willingness-to-revisit. A negative gap for this factor, on the other hand, implies that the lower the level of customer satisfaction, the lower the willingness-to-revisit. Thus, the brand factor has a comparatively greater effect on satisfaction than the other factors evaluated in this study. Given that the domestic coffee culture is becoming more upscale and college/university students are sensitive to this trend, students are attentive to brands. In most upscale coffee shops in Korea, the outer wall is built out of glass that can be opened, the interiors are exotic with an open kitchen. These upscale coffee shops function as landmarks and match the taste of college/university students. Coffee shops in Korea have become a cultural brand. To make customers feel that coffee shops are upscale, good quality establishments and measures to provide better services in terms of brand factor should be instituted. The intensified competition among coffee shop brands in Korea as a result of the booming industry indicates that provision of additional services is needed to differentiate competitors. These customers can also use a scanner free of charge. Another strategy that can be used to boost brands could be to provide and operate a seminar room for seminars and group study. If coffee shops adopt these types of strategies, college/university students would be more likely to consider the expenses they incur worthwhile and, subsequently, they would be more likely to be satisfied with the brands of these coffee shops, with an associated increase in their willingness-to-revisit. Gender and study year had the most negative effects on overall satisfaction and willingness-to-revisit. Female students were more likely to be satisfied and be willing to return than male students, and third and fourth-year students were more likely to be satisfied and willing-to-return than first or second-year students. Students who drink coffee, read books, and use laptops alone at coffee shops are easily noticeable. High-grade students tend to visit coffee shops alone in order to use their time efficiently for self-development and to find jobs. The economical efficiency factor had the greatest effect on overall satisfaction and willingness-to-revisit in terms of a positive gap. The higher the actual satisfaction (gap) of students with the price of the coffee, the greater their overall satisfaction and willingness-to-revisit. Economical efficiency with a negative gap had a negative effect on willingness-to-revisit, which implies that a less negative gap will result in a greater willingness-to-revisit. Amid worsening market conditions, coffee shops located around colleges/universities are using strategies, such as a point or membership card, strategic alliances with credit-card companies, development of a set menu or seasonal menu, and free coffee-shot services to increase their competitive edge. Product power also had a negative effect in terms of a negative gap, which indicates that a higher negative gap will result in a lower willingness-to-revisit. Because there are many more customers that enjoy coffee in this decade, as compared to previous decades, the new generation of customers, namely college/university students, want various menu items in addition to coffee, and coffee shops should, therefore, add side menu items, such as waffles, rice cakes, cakes, sandwiches, and salads. For example, Starbucks Korea is making efforts to enhance product power by selling rice cakes flavored in strawberry, wormwood, and pumpkin, and providing coffee or cream free of charge. In summary, coffee shops should focus on increasing their economical efficiency, brand, and product power to enhance the satisfaction of college/university students. Because shops adjacent to colleges or universities enjoy a locational advantage, providing differentiated services in terms of economical efficiency, brand, and product power, is likely to increase customer satisfaction and return visits. Coffee shop brands should, therefore, be innovative and embrace change to meet their customers' desires. Because this study only targeted college/university students in Seoul, comparative studies targeting diverse regions and age groups are required to generalize the findings and recommendations of this study.

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Weaning Following a 60 Minutes Spontaneous Breathing Trial (1시간 자가호흡관찰에 의한 기계적 호흡치료로부터의 이탈)

  • Park, Keon-Uk;Won, Kyoung-Sook;Koh, Young-Min;Baik, Jae-Jung;Chung, Yeon-Tae
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.3
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    • pp.361-369
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    • 1995
  • Background: A number of different weaning techniques can be employed such as spontaneous breathing trial, Intermittent mandatory ventilation(IMV) or Pressure support ventilation(PSV). However, the conclusive data indicating the superiority of one technique over another have not been published. Usually, a conventional spontaneous breathing trial is undertaken by supplying humidified $O_2$ through T-shaped adaptor connected to endotracheal tube or tracheostomy tube. In Korea, T-tube trial is not popular because the high-flow oxygen system is not always available. Also, the timing of extubation is not conclusive and depends on clinical experiences. It is known that to withdraw the endotracheal tube after weaning is far better than to go through any period. The tube produces varying degrees of resistance depending on its internal diameter and the flow rates encountered. The purpose of present study is to evaluate the effectiveness of weaning and extubation following a 60 minutes spontaneous breathing trial with simple oxygen supply through the endotracheal tube. Methods: We analyzed the result of weaning and extubation following a 60 minutes spontaneous breathing trial with simple oxygen supply through the endotracheal tube in 18 subjects from June, 1993 to June, 1994. They consisted of 9 males and 9 females. The duration of mechanical ventilation was from 38 hours to 341 hours(mean: $105.9{\pm}83.4$ hours). In all cases, the cause of ventilator dependency should be identified and precipitating factors should be corrected. The weaning trial was done when the patient became alert and arterial $O_2$ tension was adequate($PaO_2$ > 55mmHg) with an inspired oxygen fraction of 40%. We conducted a careful physical examination when the patient was breathing spontaneously through the endotracheal tube. Failure of weaning trial was signaled by cyanosis, sweating, paradoxical respiration, intercostal recession. Weaning failure was defined as the need for mechanical ventilation within 48 hours. Results: In 19 weaning trials of 18 patients, successful weaning and extubation was possible in 16/19(84.2 %). During the trial of spontaneous breathing for 60 minutes through the endotracheal tube, the patients who could wean developed slight increase in respiratory rates but significant changes of arterial blood gas values were not noted. But, the patients who failed weaning trial showed the marked increase in respiratory rates without significant changes of arterial blood gas values. Conclusion: The result of present study indicates that weaning from mechanical ventilation following a 60 minutes spontaneous breathing with $O_2$ supply through the endotracheal tube is a simple and effective method. Extubation can be done at the same time of successful weaning except for endobronchial toilet or airway protection.

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Comparative growth and development of the metacercariae of Fibricola seorszensis (Trematoda: Diplostomidae) in vitro, in vivo and on the chick chorioallantois (Fibricolu seoulensis (Trematoda: Diplostomidae) 피낭유충의 in vitro, in vivo 및 닭 장뇨막 상에서의 생존 및 발육 성장 비교)

  • 서병설
    • Parasites, Hosts and Diseases
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    • v.27 no.4
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    • pp.231-248
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    • 1989
  • The growth and development of the metacercariae of F. seoulensis cultivated in vitro or on the chick chorioallantois were assessed by comparison with the optimum process of maturation in albino rats and new born chickens. The process of maturation was divided for convenience into six stages: Stage 1 ; cell multiplication, Stage 2; body shaping, Stage 3; separation of genital anlagen, Stage :1 organogeny, Stage 5; gametogony, and Stage 6: oviposition. In Hank's and Tyrode's .solutions, the metacercariae were alive up to 200 days or more at $4^{\circ}C$ without any development. The in vivo maturation process in rats or chicks was as follows: stage 1 from 6 hours; stage 2 from 24 hours; stage 3 from 48 to 72 hours; stage 4 from 3 to 4 days; stage 5 from 4 to 5 days; and stage 6 from 5 to 8 days. Despite unsuccessful infection of the metacercariae to 12 day old chicks, fully mature worms of stage 5 or 6 were recovered from new born chicks (1 to 2 days old), The metacercariae of F. seoulensis grown in vitro were up to stage 3 and no further maturation was observed. Of various media employed, the medium NCTC 109 (Gibco) or NCTC 135(Gibco) supplemented with 20% egg yolk or 20% whole egg macerate or 0.5% yeast was basically required for the earlier development of the fluke. It took 16.1 days(in average) to reach the stage 3 after cultivation. The metacercariae cultivated on the chorioallantoic membranes of 6∼13 day old chick embryo at 37∼38℃ showed their full development up to stage 5 or 6. However, the worms were in general remarkably retarded, compared with those grown in rats or chickens. In the experiments of worm transplant, although the transfer was failed from in vitro culture to in vivo of rats(Per os), the transplants from in vitro culture to the chorioallantois and from the choriollantois to in vivo of rat host were successful with or without development of the transferred worms. In the present study, it was observed that the metacercariae of F, seoulensis can be maintained in vitro media with poor development as well as fully matured in 1 to 2 day-old chicks or on the chorioallantois at a very low rate.

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Second allogeneic hematopoietic stem cell transplantation in children to overcome graft failure or relapse after initial transplant (조혈모세포이식 후 생착 실패나 재발한 소아환자에서 2차 이식의 의의)

  • Kim, Dong-Yeon;Kim, Do Kyun;Kim, Soo Young;Kim, Seok Joo;Han, Dong Gyun;Baek, Hee Jo;Kook, Hoon;Hwang, Tai-Ju
    • Clinical and Experimental Pediatrics
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    • v.49 no.12
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    • pp.1329-1339
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    • 2006
  • Purpose : Failure of hematopoietic stem cell transplantation(HSCT) may be encountered in practice because of either relapse of the malignancy or dysfunction of the graft. Second HSCT may be the only option for some patients whose initial HSCT failed. Methods : From May, 1991 to December, 2004, 115 HSCTs were performed at the Pediatric Blood & Marrow Transplantation Center, Chonnam National University. This study was a retrospective analysis of the medical records of 15 patients who received the second HSCT after initial graft. Results : Among eight patients with nonmalignant diseases, two patients underwent the second HSCT because of primary graft failure and five because of late graft rejection. The remaining Fanconi anemia patient was re-transplanted due to development of AML. Two patients died and one experienced primary graft failure, but is still alive. The Kaplan-Meier 5-year overall survival rate was 75 percent and the disease free survival rate was 62.5 percent in nonmalignant diseases. All malignant patients underwent second transplants because of relapses. Four died of relapse and one of treatment-related complications. The Kaplan-Meier 2-year overall and event free survival rate was 28.6 percent each in malignant diseases. Conclusion : Second HSCT for graft dysfunction of nonmalignant disease seems to be feasible and should be considered as a standard practice. The relapse of malignant diseases remains a big obstacle even after the second HSCT, although a small portion of patients might be salvaged. Further investigation of novel therapeutic strategies, as well an the understanding of the biology should be explored.