• Title/Summary/Keyword: Material life

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Effect of Aprotinin on Changes in Plasma Thromboxane $B_2$ and Endothelin-1 Concentratin after Extracorporeal Circulation (체외순환후 혈중 Thromboxane $B_2$와 Endothelin-1 농도 변화에 미치는 Aprotinin의 효과)

  • Lim, Cheong;Yun, Tae-jin;Kim, Yeon-seung;Kim, Seung-hoo;Lee, Jae-dam;Rho, Joon-Ryang;Song, Meong-Gun
    • Journal of Chest Surgery
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    • v.33 no.3
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    • pp.221-229
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    • 2000
  • Background: Thromboxane A2 and endothelin-1 are the potent vasoconstrictors affecting pulmonary pathophysiology in response to whole body inflammatin following CPB. Aprotinin, as an antiiflammatory agent, may decrease the release of such vasoactive substance from pulmonary tissues, preventing pulmonary hypertension after cardiopulmonary bypass. Material and Method: Ten mongrel dogs(Bwt. ac. 20kg) were subjected to cardioupulmonary bypass for 2 hours and postbypass pulmonary vascular resistance(0, 1, 2, 3 hours) were compared with prebypass level. The dogs were divided into 2 groups; control group(n-5) and aprotinin group(n=5). In the aprotinin group, aprotinin was administered as follows; 50,000 KIU/kg mixed in pump priming solution, 50,000 KIU/kg prebypass intravenous infusion over 30 minutes, 10,000 KIU/kg/hour postbypass continuous infusion. Prebypass and postbypass 0, 1, 2, 3 hour pulmonary vascular resistance were measured. At prebypass and postbypass 0, 90, 180 minutes, blood samples were obtained from pulmonary arterial and left atrial catherers for the assay of plasma thromboxane B2 a stable metabolite of thromboxane A2, and endothelin-1 concentrations. Result: The ratios of pustbypass over prebypass pulmonary vascular at postbypass 0, 1, 2, 3 hours were 1.28$\pm$0.20, 1.82$\pm$0.23, 1.90$\pm$0.19, 2.14$\pm$0.18 in control group, 1.58$\pm$0.18, 1.73$\pm$0.01, 1.66$\pm$0.10, 1.50$\pm$0.08 in aprotinin group ; the ratios gradually increased in control group while decreased or fluctuated after postbypass 1 hour in aprotinin group. There was statistically significant difference between control group and aprotinin group at postbypass 3 hours(P=0.014). Pulmonary arterial plasma concentration of thromboxane B2(pg/ml) at prebypass, postbypass 0, 90, 180 minutes were 346.4$\pm$61.9, 529.3$\pm$197.6, 578.3$\pm$255.8, 493.3$\pm$171.3 in control group, 323.8$\pm$118.0, 422.6$\pm$75.6, 412.3$\pm$59.9, 394.5$\pm$154.0 in aprotinin group. Left atrial concentrations were 339.3$\pm$89.2, 667.0$\pm$65.7, 731.2$\pm$192.7, 607.5$\pm$165.9 in control group, 330.0$\pm$111.2, 468.4$\pm$190.3, 425.4$\pm$193.6, 4.7.3$\pm$142.8 in aprotinin group. These results showed decrement of pulmonary thromboxane A2 generation in aprotinin group. Pulmonary arterial concentrations of endothelin-1(fmol/ml) at the same time sequence were 7.84$\pm$0.31, 13.2$\pm$0.51, 15.0$\pm$1.22, 16.3$\pm$1.73 in control group, 7.76$\pm$0.12, 15.3$\pm$0.71, 22.6$\pm$6.62, 14.9$\pm$1.11 in aprotinin group. Left atrial concentrations were 7.61$\pm$17.2, 57.1$\pm$28.4, 18.9$\pm$18.2, 31.5$\pm$20.5 in control group, 5.61$\pm$7.61, 37.0$\pm$26.2, 28.6$\pm$21.7, 37.8$\pm$30.6 in aprotinin group. These results showed that aprotinin had no effect on plasma endothelin-1 concentration after cardiopulmonary bypass. Conclusion: Administration of aprotinin during cardiopulmonary bypass could attenuate the increase in pulmonary vascular resistance after bypass. Inhibition of pulmonary thromboxane A2 generation was thought to be one of the mechanism of this effect. Aprotinin had no effect on postbypass endothelin-1 concentration.

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Risk Factor, Mortality and Infection Rate of Mediastinum After Delayed Sternal Closure in Congenital Heart Surgery Patients (선천성 심장수술 후 지연 흉골 봉합시 사망률 및 종격동 감염률 그리고 위험인자)

  • 이진구;박한기;홍유선;박영환;조범구
    • Journal of Chest Surgery
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    • v.35 no.7
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    • pp.517-522
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    • 2002
  • Background: Congenital heart surgery may lead to myocardial swelling and hemodynamic instability. Delayed sternal closure may be beneficial in this setting. The purpose of this study was to assess mortality and mediastinal infection rate associated with delayed sternal closure after congenital heart surgery and to evaluate the risk factors which affect mortality and mediastinal infection rate. Material and Method: We retrospectively reviewed 40 patients who underwent delayed sternal closure after repair of congenital heart disease at Yonsei Cardiovascular Hospital, from January 1994 to May 2001. In these patients, we assessed the mortality and mediastinal infection rate, and evaluated their risk factors including operation time, bypass time, aortic cross clamp time, duration to sternal closure and postoperative artificial ventilation time. Mediastinal infection was defined to have positive culture in mediastinum. Result: Hemodynamic instability was the most common indication for delayed sternal closure(n=36) and other indications included postoperative bleeding(n=2) and conduit compression(n=2). The median age at operation was $14.4{\pm}33.4$months old(range, 2days-12years). The patients with postoperative bleeding and conduit compression were much older than the others. The sternum was left open for $4.5{\pm}3.4$ days(range, 1-20days). Overall mortality was 25%(10/40) and mediastinal infection occured in 24.3%(9/37) (3 patients were excluded in mediastinal infection for early death). In risk factor analyses, only aortic cross clamp time had statistical significance for mortality in univariate analyses. However, multivariate analyses revealed that there were no significant predictors for risk of mortality and mediastinal infection. Conclusion: Delayed sternal closure after repair of congenital cardiac disease had relatively high mortality and mediastinal infection rate. But, in patients with hemodynamic instability, postoperative bleeding and conduit compression after repair of congenital cardiac disease, delayed sternal closure may be an effective life saving method.

20-Year Experience of Surgical Treatment for Postpneumonectomy Empyema (전폐절제술 후 사강에 발생한 농흉의 치료)

  • 김형렬;김영태;성숙환;김주현
    • Journal of Chest Surgery
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    • v.35 no.7
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    • pp.542-547
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    • 2002
  • Background: Postpneumonectomy empyema(PPE) is an infrequent but potentially life-threatening complication. To date, various surgical efforts have been made to manage this complication. We reviewed our 20-year surgical experience of PPE and long-term follow-up data. Material and Method: Total of 37 patients who were treated for PPE between fan, 1980 and Jun, 2000 were included. Various clinical factors such as micro-organism, operative method and timing, presence of bronchopleural fistula(BPF), underlying disease and fate of empyema cavity were retrospectively reviewed and analyzed. Result: Majority of patients(34) underwent Eloesser operation for effective drainage. There was only one operative mortality. The causative organisms were Staphylococcus species and Pseudomonas species in 46% BPF was found in 20 cases, among which spontaneous closures took place in 4 cases. The chest wall was closed in 40%(8/20) of patients with BPF, compared to 59%(10/17) without BPF. The closure rate was statistically better in patients without BPF(p=0.006). Even though the patients with benign disease showed higher closure rate(50%) than those with lung cancer (31%), the difference was not significant(p=0.25). Conclusion: Eloesser procedure was an effective method for initial drainage of PPE cavity with low operative mortality. Given the findings of low spontaneous closure rate of BPF, aggressive approach to close the BPF is mandatory to achieve the final goal of chest wall closure. It was found that majority of patients still left their chest cavity opened, even after controlling the active inflammation of the empyema cavity. More aggnessive approach for chest wall closure is recommended in all patents with benign disease and in selective patients with lung cancer if there is no evidence of recurrence at several years after the initial operation.

The Efficacy of Endovascular Treatment for Deep Vein Thrombosis (하지 심부정맥 혈전증에서 중재적 치료의 유용성)

  • Kim, Seon-Hee;Chung, Sung-Woon;Kim, Chang-Won
    • Journal of Chest Surgery
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    • v.43 no.3
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    • pp.266-272
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    • 2010
  • Background: Deep vein thrombosis (DVT) is a serious disease that causes life-threatening pulmonary embolism and chronic venous insufficiency. Anticoagulation is the standard therapy for DVT. However, the results of standard anticoagulation for treating DVT have been disappointing, so endovascular treatment is commonly performed nowadays. The aim of this study was to evaluate the efficacy of an endovascular procedure for treating patients with DVT. Material and Method: We retrospectively evaluated the clinical data of 29 DVT patients who underwent an endovascular procedure between December 2006 and July 2008. We compared the results of the 29 patients with the results of another 45 patients who were treated with only aspirin and heparin. Result: The patient’s mean age was 55.4 years in the intervention group and 53.7 years in the control group. DVT occurred more frequently in the females. Catheter-directed thrombolysis was performed in 22 patients (75.8%). Aspiration thrombectomy was performed in 18 patients (62%) and a endovascular stent was placed in 25 patients (86.2%). Fifteen patients (51.7%) underwent percutaneous insertion of a retrievable IVC filter for the prevention of pulmonary embolism. In the control group, thirty nine patients (86.7%) were treated with low-molecular heparin, and seven patients (15.6%) who were contraindicated for warfarin were treated with aspirin. No bleeding complications occurred during thrombolysis or anticoagulation. We analyzed the statistical data according to recurrence of DVT and the incidence of post-thrombotic syndrome (PTS) during the follow-up period. The intervention group had a significantly lower incidence of PTS (p-value=0.008), but they had the same result as the control group for the recurrence of DVT. In addition, death from the DVT did not occur in the intervention group. Thus, we obtained better clinical outcomes in the intervention group as compared to those in the anticoagulation only group. Conclusion: Endovascular procedures are effective alternative modalities, as compared to systemic anticoagulation, for the treatment of DVT. But more studies are needed to determine the specific indications and to validate the long-term efficacy of endovascular procedures for the treatment of DVT.

The Clinical Outcome of Pulmonary Thromboendarterectomy for the Treatment of Chronic Pulmonary Thromboembolism (만성 폐동맥 색전증 환자에서의 폐동맥 내막절제술의 임상적 결과)

  • Bang, Jeong-Hee;Woo, Jong-Soo;Choi, Pil-Jo;Jo, Gwang-Jo;Park, Kwon-Jae;Kim, Si-Ho;Yie, Kil-Soo
    • Journal of Chest Surgery
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    • v.43 no.3
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    • pp.254-259
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    • 2010
  • Background: Diagnosing chronic pulmonary embolism at an early stage is difficult because of the patient’s nonspecific symptoms. This condition is not prevalent in Korea, and in fact, there have been only a few case reports on this in the Korean medical literature. We analyzed the surgical outcome of performing pulmonary thromboendarterectomy in patients with chronic pulmonary embolism. Material and Method: The study subjects included those patients who underwent surgery for chronic pulmonary embolism from 1996 to 2008. For making the diagnosis, echocardiography, chest CT and a pulmonary perfusion scan were performed on the patients who complained of chronic dyspnea. Result: Pulmonary endarterectomy was performed as follows: by incision via a mid-sternal approach (7 patients); by incision via a left posterolateral approach (1 patient); using the deep hypothermic circulatory arrest technique (4 patients); under ventricular fibrillation (3 patients); and under cardioplegic arrest (1 patient). The postoperative systolic pulmonary artery blood pressure significantly decreased from a preoperative value of $78.9{\pm}14.5\;mmHg$ to $45.6{\pm}17.6\;mmHg$ postoperatively (p=0.000). The degree of tricuspid regurgitation was less than grade II after surgery. Two patients died early on, including one patient who had persistent pulmonary hypertension without improvement and right heart failure. Conclusion: Patients who have chronic pulmonary embolism are known to have a poor prognosis. However, we think that early surgical treatment along with making the proper diagnosis before the aggravation of right heart failure can help improve the quality of a patient's life.

Clinical Appilication of Endobornchial Cryoablation That's Performed through Flexible Bronchoscope for Treating Tracheobronchial Ostruction (기관 및 기관지 폐색환자에서 굴곡형 기관지내시경을 이용한 냉동수술의 임상적용)

  • Lee, Sung-Ho;Kim, Kwang-Taik;Chung, Jae-Ho;Chung, Won-Jae;Kang, Moon-Chul;Kang, Eun-Hae;Lee, Eun-Joo;In, Kwang-Ho
    • Journal of Chest Surgery
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    • v.41 no.4
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    • pp.457-462
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    • 2008
  • Background: Emergency airway access is essential when a patient has dyspnea that's due to tracheal or bronchial obstruction. Such methods as laser therapy and PDT are now being used for the treatment of tracheal obstruction that's due to benign diseases or nonsurgical malignant diseases. Cryotherapy is a method that uses extreme hypothermia for freezing a tumor to cause necrosis. In this study, we have evaluated the clinical effectiveness of performing endobronchial cryoablation through a flexible bronchoscope. Material and Method: 10 patients with tracheal obstruction that was due to endotracheal tumors were evaluated between May 2005 and May 2007. Eight were male and the mean age of the 10 patients was $59.4{\pm}18.4$ years. Three cases of tracheal obstruction were due to benign tumors and 7 were due to malignant tumors. The obstruction sites were 3 at the trachea, 3 at the carina and 4 at the bronchus. A flexible bronchoscope was inserted and the tumor was eliminated using a flexible cryoprobe. Follow up bronchoscopy was performed at 1 week and 1 month after cryoablation, and then we evaluated the decrease of dyspnea, the improvement of the performance and the complications of the procedures. Result: Complete remission was achieved in 4 patients and partial remission was achieved in 6 patients. Complications such as hemoptysis (100%), and cough (50%) were noted. Hemoptysis was spontaneously resolved in 3 to 8 days (mean: 4.9 days). A decrease in dyspnea and improvement in the performance was noted in all patients. Conclusion: Endobronchial stenosis plays a detrimental role in the life quality of a terminal cancer patient. Due to its simplicity and effectiveness for controlling bleeding, endobronchial cryoablation is considered to be a safe method that is clinically applicable to a wide range of tumors, including the removal of large tumors. We concluded that endobronchial cryoablation through a flexible bronchoscope is a safe, effective method for treating tracheobroncheal obstructions.

Study on the Antioxidant Effects of Nano-Selenium Microcapsule (Nano-Selenium Microcapsule의 항산화에 관한 연구)

  • Jeong, Hun;Yoo, Il-Su;Kim, Kyung-Sun;Lee, Soon-Young;Mun, Yeun-Ja;Jeon, Byoung-Kook;Ryu, Moon-Hee;Choi, Kyung-Soon
    • The Korean Journal of Food And Nutrition
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    • v.25 no.3
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    • pp.564-569
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    • 2012
  • Selenium was initially considered toxic to humans, but it was then discovered that selenium is essential for normal life processes. Selenium plays important roles in antioxidants. It is expected that chitosan microcapsules containing nano-selenium will be able to be used as a key material in bio-medical and cosmetic applications. The high concentration of chitosan derivatives guarantees increased antioxidative activity. Both inorganic and organic forms of selenium can be nutritional sources. The antioxidant properties of selenoproteins help prevent cellular damage from free radicals. The objective of this experiment was to study the antioxidative activity of chitosan nano-selenium. Our experiments were divided into five groups, in the presence of various concentrations(0.1%, 0.3%, 0.5%, 0.7%, and 0.9%) of chitosan. We performed an assessment of the antioxidant properties and cytotoxicity of respective concentrations of chitosan nano-selenium. The antioxidant activity was examined by the free radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl(DPPH) assay. The cytotoxicity effect was measured by means of 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. As a result, the electron donating abilities of 0.1%, 0.3%, 0.5%, 0.7%, and 0.9% of chitosan nano-selenium exhibited effective andioxidant scavenging activity at 12.5 ${\mu}g/m{\ell}$ against DPPH radicals. 0.3% chitosan nano-selenium did not show cytotoxicity on human keratinocytes. In general, the cytotoxicity of 0.1% and 0.9% chitosan nano-selenium showed the lowest effects. Though low cytotoxicity of 0.5% and 0.7% chitosan nano-selenium exhibited 29.67% and 38.4% against human keratinocytes on adding 100 ${\mu}g/m{\ell}$ and 50 ${\mu}g/m{\ell}$, respectively, cell vitality was recovered with 200 ${\mu}g/m{\ell}$. These findings support the notion that chitosan nano-selenium may be useful as a new active ingredient source for bioactive compounds.

Oral health status and treatment need of institutionalized elderly patients (노인요양시설에 있는 노인환자의 구강실태 및 치료수요도)

  • Yang, Soon-Bong;Moon, Hong-Suk;Han, Dong-Hoo;Lee, Ho-Yong;Chung, Moon-Kyu
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.5
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    • pp.455-469
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    • 2008
  • Statement of problems: In the area of dental care, the institutionalized elderly have placed the most vulnerable state, and we cannot find their subjective need of dental treatment because of the physical and mental disabilities, But we have no basic investigation of their oral health conditions. Purpose: The aims of the current study were to investigate the oral health status of institutionalized elderly patients who are in the least benefited side of dental service, and to analyze their dental treatment needs. Material and methods: The survey of the oral status was carried out on 758 institutionalized elderly, and 212 elderly who was more than 65 years old from D dental office, and it was based on the Guidelines of Oral Health Research of year 2000 in Republic of Korea. Results and conclusion: The DMFT index of the institutionalized elderly appeared higher than that of the same ages in control group, and it increased with age. The number of residual teeth of the institutionalized elderly appeared lower than that of the same ages in control group, and it decreased with age (P < .05). The number of fixed partial denture in institutionalized elderly was lower than that of the same ages in control group (P < .05). The percentage wearing removable partial denture was not significant between the elderly in institutions and the control group, and was not different according to age between the two groups. The percentage of institutionalized elderly wearing complete denture appeared lower than that of the same ages in control group, and it increased with age. The percentage of institutionalized elderly needing complete denture was higher than that of control group, and the percentage of elderly needing complete denture on the maxilla was higher than that of the mandible. 16.35% of the institutionalized elderly was living without denture in spite of their fully edentulous state. The need for complete denture increased rapidly with age. The number of valued teeth and dental prostheses in shortened dental arch concept and number of occluding pairs of teeth of institutionalized elderly were lower than that of the control group (P < .05). In institutionalized elderly, the number of residual teeth, the number of fixed partial dentures, and the percentage wearing removable partial dentures were higher in the mandible, and the percentage wearing complete dentures was higher in the maxilla (P < .05). The rate of institutionalized elderly needing prosthodontic treatment appeared to be 67.82%, where the number of occluding pairs of teeth was less than 10. When it is difficult to evaluate the subjective need of dental treatment as with the institutionalized elderly, estimation using the number of occluding pairs of teeth can be a useful indicator that can project treatment needs. For the oral health care of institutionalized elderly, it is essential to increase the awareness of nurses and caregivers who take care of them, about the importance of the oral health. Since the average life span and number of residual teeth are increasing gradually, the welfare policy should be changed to implementing regular dental examinations, preservative treatment forms and oral health control of dentulous patients where the traveling-treatment system and visit system are supplemented. And principles should be set that the present denture project of edentulous patients should be done by specialists who'll also be responsible for postmanagement. Through this research of institutionalized elderly, the oral health status which is worsened by aging could be confirmed. And the interest and positive participation of dental society on the elderly should come first in order to solve the rising treatment needs of the elderly patients.

Demands for Health Education through Internet in Middle and High School Students (중.고등학교 학생들의 인터넷을 이용한 보건교육 요구도)

  • Kang, Pock-Soo;Choi, Yeun-Hwa;Lee, Kyeong-Soo;Hwang, Tae-Yoon
    • Journal of Yeungnam Medical Science
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    • v.21 no.1
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    • pp.23-39
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    • 2004
  • Background: It is important to provide health education to students to ensure a healthy life. Using the internet for health education may be a way to overcome the practical barriers to health education such as time and content. This study was conducted to investigate the demands for health education using the internet. Subjects and methods: Six hundreds and twenty-four and male female students in middle and high schools, who lived on Gyeongju-si and Seongju-gun in Gyeongsangbuk-do province, were interviewed by means of structured questionnaires, from March 5 to March 28, 2003. Results: More than 90% of the subjects had their own computers, and nearly 38% of those possessing their own computers had accessed internet sites related to health and medicine. Middle school students and in particular, female students were more desirous for health education through e-mail. Regarding content, the three major topics which the respondents wanted to learn about were healthy lifestyles, growth and development, and disease prevention. In terms of the interval for providing educational materials, over half of the students wanted information once a week. Most of the students wanted to have the quantity of the material be one page. In addition, there were numerous additional topics requested by the students such as sleep and health, contraception and family planning, safety education, cancer prevention, emotional instability of juveniles, the utilization of medical care facilities, stress management, etc. Conclusion: The students had a desire for health education through the use of e-mail, and methods and materials should be developed for appropriate health education using the internet.

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Limitations on Exclusive Rights of Authors for Library Reprography : A Comparative Examination of the Draft Revision of Korean Copyright Law with the New American Copyright Act of 1976 (저작권법에 준한 도서관봉사에 관한 연구 -미국과 한국의 저자재산권의 제한규정을 중시으로-)

  • 김향신
    • Journal of Korean Library and Information Science Society
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    • v.11
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    • pp.69-99
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    • 1984
  • A dramatic development in the new technology of copying materials has presented us with massive problems on reconciling the conflicts between copyright owners and potential users of copyrighted materials. The adaptation to this changing condition led some countries to revise their copyright laws such as in the U. S. in 1976 and in Korea in 1984 for merging with the international or universal copyright conventions in the future. Copyright defined as exclusive rights given to copyright owners aims to secure a fair return for an author's creative labor and to stimulate artistic creativity for the general public good. The exclusive rights on copyrightable matters, generally for reproduction, preparation of derivative works, public distribution, public performance, and public display, are limited by fair use for scholarship and criticism and by library reproduction for its preservation and interlibrary loan. These limitations on the exclusive rights are concerned with all aspects of library services and cause a great burden on librarian's daily duty to provide balance between the rights of creators and the needs of library patrons. The fair use as one of the limitations on it has been coupled with enormous growth of a new technology and extended from xerography to online database systems. The implementation of the fair use and library reprography in Korean law to the local practices is examined on the basis of the new American copyright act of 1976. Under the draft revision of Korean law, librarians will face many potential problems as summarized below. 1. Because the new provision of 'life time plus 50 years' will tie up substantial bodies of material longer than the old law, until that date librarians would need permissions from the owners and should pay attention to the author's death date. 2. Because the copyright can be sold, distributed, given to the heirs, donated, as a whole or a part, librarians should chase down the heirs and other second owners. In case of a derivative work, this is a real problem. 3. Since a work has its protection from the moment of its creation, the coverage of copyrightable matter would be extended to the published or the unpublished works and librarian's work load would be heavier. Without copyright registration, no one can be certain that a work is in the public domain. Therefore, librarians will need to check with an authority. 4. For implementation of limitations on exclusive rights, fair use and library reproduction for interlibrary loan, there can be no substantial aggregate use and there can be no systematic distribution of multicopies. Therefore, librarians should not substitute reproductions for subscriptions or purchases. 5. For the interlibrary loan by photocopying, librarians should understand the procedure of royalty payment. 6. Compulsory licenses should be understood by librarians. 7. Because the draft revision of Korean law is a reciprocal treaty, librarians should take care of other countries' copyright law to protect foreign authors from Korean law. In order to solve the above problems, some suggestions are presented below. 1. That copyright clearinghouse or central agency as a centralized royalty payment mechanism be established. 2. That the Korean Library Association establish a committee on copyright. 3. That the Korean Library Association propose guidelines for each occasion, e.g. for interlibrary loan, books and periodicals and music, etc. 4. That the Korean government establish a copyright office or an official organization for copyright control other than the copyright committee already organized by the government. 5. That the Korean Library Association establish educational programs on copyright for librarians through seminars or articles written in its magazines. 6. That individual libraries provide librarian's copyright kits. 7. That school libraries distribute subject bibliographies on copyright law to teachers. However, librarians should keep in mind that limitations on exclusive rights are not for an exemption from library reprography but as a convenient access to library resources.

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