• Journal of Yeungnam Medical Science
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• v.16 no.1
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• pp.76-84
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• 1999

The differentiation between malignancy-related ascites(MRA) and non-malignant ascites (NMA) is important for further diagnostic and therapeutic purposes. Although many parameters were investigated, none has provided a complete distinction between MRA and NMA. We investigated several ascitic fluid parameters to determine the differential power, and to differentiate malignant-related from nonmalignant-related ascites with a sequence of sensitive parameters followed by specific parameters. For the present study, 80 patients with ascites were divided into two groups: MRA and NMA, The MRA group was consisted of 27 patients with proven malignancy by image study, biopsy, and follow up: 21 of these patients had peritoneal carcinomatosis, but the remaining 6 showed no evidence of peritoneal carcinomatosis. The NMA group was consisted of 53 patients with no evidence of malignancy: among these patients, one had SLE, and others had liver cirrhosis, The samples of blood and ascites were obtained simultaneously, and then the levels of ascites cholesterol, CEA. protein and LDH, cytology, albumin gradient, ascites/serum concen-tration ratios of LDH(LDH A/S), and ascites/serum concentration ratios of protein(protein A/S) were measured. Applying cut-off limits for determined parameters, we estimated the diagnostic efficacy of each parameter, Among the eight parameters investigated, ascites fluid cholesterol yielded the best sensitive value of 93%(cut-off value 30mg/dl), and cytologic examination and the protein A/S(cut-off value 0.5) showed the most specific value of 100% and 96%, respectively. Based on the above results, the diagnostic sequence with cholesterol as a sensitive parameter followed by the combination of cytologic examination and protein A/S as specific parameters, was tested in 80 patients. This diagnostic sequence identified 81.5% of patients with malignancy, and all patients with peritoneal carcinomatosis were classified as malignancy-related ascites. In spite of many limitations, this proposed diagnostic sequence may permit a cost-effective and simple differentiation of malignancy-related ascites from nonmalignant ascites.

• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.3
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• pp.257-265
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• 2014

The aim of this study was to establish the appropriate guidelines in the sedation techniques and to organize the continuing education programs for the sedation in future under the direction of Committee on Sedation, Education and Research under the Korean Academy of Pediatric Dentistry(KAPD). The surveys on the sedation technique were performed on 111 organizations which practices the sedation and responded to the survey via online and e-mail by February 2014. The collected survey were analyzed. The purpose of sedation was mainly to manage the children's behavior and its uses were primarily on 3~4 years old children. The most frequent duration of treatment was 1~2 hours to treat both maxillary and mandible. The preferred dosages of sedative drugs were chloral hydrate(CH) 50~70 mg/kg, hydorxyzine(Hx) 1~2 mg/kg, and intramuscular midazolam(Mida IM) 0.1~0.2 mg/kg. The preferred combination of the sedative drugs were CH + Hx + $N_2O/O_2$(67.6%), CH + Hx + Mida submucosal administration (SM) + $N_2O/O_2$(29.7%), and Mida IM + $N_2O/O_2$(23.4%). The administration of additional sedatives was carried out at 48%, mainly using Midazolam. 87.5% of the respondents experienced the adverse effects of the sedation such as vomiting/retching, agitation during recovery, subclinical respiratory depression, staggering, and etc. Among them, only 20% periodically retrain the emergency management protocol. About the discharge criteria for patients after the sedation, the respondents either showed a lack of clear criteria or did not follow the recommended discharge criteria. 86% of the respondents expressed the interests in taking a course on the sedation and they wanted to learn mostly about the sedation-related emergency management, the safe dosage of the sedative drugs, and etc. The use of sedation in pediatric dentistry must be consider a patient's safety as top priority and each dentist must show the evidence of sound practices for the prevention of any possible medical errors. Therefore, KAPD must establish the proper sedation guidelines and it needs to provide the systematic technical training program of sedation-related emergency management for pediatric dentists.

• Journal of Oral Medicine and Pain
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• v.34 no.2
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• pp.207-216
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• 2009

Trigeminal neuralgia is defined "a sudden, usually unilateral, severe, brief, stabbing, recurrent pain in the distribution of one or more branches of the fifth cranial nerve". The initial treatment of choice for trigeminal neuralgia is medical therapy. In patients with medically intractable pain or intolerable medication side effects, invasive therapeutic approaches are often necessary. Based on the amount of evidence and estimated efficacy, carbamazepine is the drug of choice in the management of trigeminal neuralgia. In case of insufficient or no response to carbamazepine, second-line drugs can be added. In this study, the author tried to review and analyzed the cases of 90 patients whom had visited for treatment of trigeminal neuralgia at the Department of Oral Medicine, Kyungpook National University Hospital from 2003 to 2008. The results were as follows: 1. Trigeminal neuralgia was significantly more common with advancing age, and nearly twice as common in women than men (ratio of 2.1:1) 2. The maxillary branch of the trigeminal nerve involved most often (51.1%), and the right side of the face is affected more commonly than the left (ratio of 2.9:1). 3. 85(94.4%) patients had experiences visiting medical or dental specialties before being referred to the Department of Oral Medicine. 4. 40(44.4%) patients with trigeminal neuralgia had systemic diseases. 5. Treatment with carbamazepine monotherapy was satisfactory initially in 69(76.7%) the patients, and the mean daily dose of carbamazepine was 402.9mg. On the other hand, 16(17.8%) patients expressed effectiveness after combination therapy of carbamazepine and other drugs. 6. Of the 69 patients who had a good initial response to carbamazepine monotherapy, 18 patients became resistant, so that combination therapy of carbamazepine and other drugs were necessary. 7. 54(60%) patients developed side effects such as dizziness, drowsiness, nausea, vomiting, blood dyscrasias, skin rash and constipation, and 11 of the patients decided to stop tmedicaion due to side effects.

• Journal of Environmental Policy
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• v.13 no.4
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• pp.3-49
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• 2014

Growing interest of stakeholders on corporate responsibilities for environment and tightening environmental regulations are highlighting the importance of environmental management more than ever. However, companies' awareness of the importance of environment is still falling behind, and related academic works have not shown consistent conclusions on the relationship between environmental performance and economic performance. One of the reasons is different ways of measuring these two performances. The evaluation scope of economic performance is relatively narrow and the performance can be measured by a unified unit such as price, while the scope of environmental performance is diverse and a wide range of units are used for measuring environmental performances instead of using a single unified unit. Therefore, the results of works can be different depending on the performance indicators selected. In order to resolve this problem, generalized and standardized performance indicators should be developed. In particular, the performance indicators should be able to cover the concepts of both environmental and economic performances because the recent idea of environmental management has expanded to encompass the concept of sustainability. Another reason is that most of the current researches tend to focus on the motive of environmental investments and environmental performance, and do not offer a guideline for an effective implementation strategy for environmental management. For example, a process improvement strategy or a market discrimination strategy can be deployed through comparing the environment competitiveness among the companies in the same or similar industries, so that a virtuous cyclical relationship between environmental and economic performances can be secured. A novel method for measuring eco-efficiency by utilizing Data Envelopment Analysis (DEA), which is able to combine multiple environmental and economic performances, is proposed in this report. Based on the eco-efficiencies, the environmental competitiveness is analyzed and the optimal combination of inputs and outputs are recommended for improving the eco-efficiencies of inefficient firms. Furthermore, the panel analysis is applied to the causal relationship between eco-efficiency and economic performance, and the pooled regression model is used to investigate the relationship between eco-efficiency and economic performance. The four-year eco-efficiencies between 2010 and 2013 of 23 companies are obtained from the DEA analysis; a comparison of efficiencies among 23 companies is carried out in terms of technical efficiency(TE), pure technical efficiency(PTE) and scale efficiency(SE), and then a set of recommendations for optimal combination of inputs and outputs are suggested for the inefficient companies. Furthermore, the experimental results with the panel analysis have demonstrated the causality from eco-efficiency to economic performance. The results of the pooled regression have shown that eco-efficiency positively affect financial perform ances(ROA and ROS) of the companies, as well as firm values(Tobin Q, stock price, and stock returns). This report proposes a novel approach for generating standardized performance indicators obtained from multiple environmental and economic performances, so that it is able to enhance the generality of relevant researches and provide a deep insight into the sustainability of environmental management. Furthermore, using efficiency indicators obtained from the DEA model, the cause of change in eco-efficiency can be investigated and an effective strategy for environmental management can be suggested. Finally, this report can be a motive for environmental management by providing empirical evidence that environmental investments can improve economic performance.

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1083-1093
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• 1997

Background : So far, there have been numerous reports on organ damage due to cryptococcosis, however, cases of lung localization have been infrequently reported. Recently pulmonary cryptococcosis has been reported more frequently than before due to enhanced diagnostic techniques and increased underlying diseases. Method : The author, therefore, analyzed the clinical manifestations of 5 cryptococcosis cases that we experienced at Hanyang University Hospital from 1985 to 1996 and 9 cases reported in Korea from 1984 and 1996 retrospectively. The following results were obtained. Results : Cryptococcosis occurred frequently over sixth decade and the male to female ratio was 3.6 : 1. Underlying diseases included acute rejection after kidney transplantation, rheumatoid arthritis, autoimmune hepatitis, diabetes mellitus and state of bilateral adrenalectomy. Remaining 8 cases had no evidence of an underlying disease. Because the symptoms were subacute & nonspecific, and not improved by conventional antibiotics, 6 patients of 14 pulmonary cryptococcosis patients were treated as pulmonary tuberculosis before correct diagnosis was made. There were three asymptomatic cases. According to the results of CXR, solitary alveolar consolidation was the most common finding(8 cases) followed by diffuse infiltration(5 cases). It also showed pleural effusion, hilar lymphadenopathy and cavity formation that was rarely reported in world literature. The diagnasis was made through fine needle aspiration biopsy in 10 cases, open thoracotomy in 2 cases, transbronchial lung biopsy in 1 case. and thoracentesis with pleural biopsy in 1 case. Only one case showed positive result in sputum stain and culture, serum latex agglutination test for cryptococcus neoformans. Treatment modalities were various such as fluconazole, amphotericin B, flucytosine, ketoconazole, surgery and it's combination. After 1990 year, there was a trend that fluconazole or ketoconazole are more used than other therapeutic modalities. Conclusion : Because the symptoms are subacute & nonspecific and not improved by conventional antibiotics, pulmonary cryptococcosis is likely to misdiagnosis as pulmonary tuberculosis in Korea. Because the diagnosic yield of sputum stain, culture and serologic test for pulmonary cryptococcosis is low, histologic diagnosis is need in most pulmonary cryptococcosis.

• Journal of Korea Technology Innovation Society
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• v.20 no.1
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• pp.1-33
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• 2017

In the last decades, technology-oriented small firms, i.e. venture businesses, have been increasingly engaged in R&D collaborations with external parties as strategic means for technological innovation. Despite ample evidence on the benefit of such collaborations for the firms, there has been less attention to examining whether and how the firms' social interactions with cooperating partners and their managerial characteristics contribute to that benefit. Drawing on the theories of social capital and entrepreneurial orientation, this study is to remedy this gap. The theory of social capital, referring to a sum of the value and potential resources embedded in social relationships of collectives, provides an integrated view of social factors among cooperating partners, e.g. strong ties, network stability, trust, reciprocity, shared vision and value. It categorizes these factors into structural, relational, and cognitive dimensions of social capital. Entrepreneurial orientation theory captures firms' managerial characteristics as a combination of innovativeness, proactiveness, and risk-taking. This addresses firms' managerial process to utilize and combine internal and external resources for wealth creation and opportunity realization. Against this background, this study investigates what roles social capital among cooperating R&D partners and entrepreneurial orientation of the collaborating firms play for collective performance improvement in R&D collaborations. In terms of the collective performance, this study adopts two indicators: technological competitiveness and business performance. Technological competitiveness refers to the contribution of a technology developed by a cooperative R&D project to competitive advantage of a firm while business performance is defined as the financial and economic outcome of a collaboration. Using a sample of 218 Korean ventures engaging in R&D collaboration with external parties, the author finds the significant effects of social capital (i.e. structural, relational, and cognitive dimensions) and entrepreneurial orientation (i.e. innovativeness, proactiveness, and risk-taking) on both of the technological competitiveness and the business performance. Further, the higher the social capital among R&D partners, the more likely it is to foster the entrepreneurial orientation at firm-level. Most importantly, the entrepreneurial orientation at firm-level is an significant mediator of the relationship between social capital and collective performance. Beyond these novel empirical findings, this study contributes to the literature on R&D collaboration. The findings' implications for management and policy are deeply discussed in the conclusion.

• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.227-240
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• 2011

New concepts and ideas often result from extensive recombination of existing concepts or ideas. Both researchers and developers build on existing concepts and ideas in published papers or registered patents to develop new theories and technologies that in turn serve as a basis for further development. As the importance of patent increases, so does that of patent analysis. Patent analysis is largely divided into network-based and keyword-based analyses. The former lacks its ability to analyze information technology in details while the letter is unable to identify the relationship between such technologies. In order to overcome the limitations of network-based and keyword-based analyses, this study, which blends those two methods, suggests the keyword network based analysis methodology. In this study, we collected significant technology information in each patent that is related to Light Emitting Diode (LED) through text mining, built a keyword network, and then executed a community network analysis on the collected data. The results of analysis are as the following. First, the patent keyword network indicated very low density and exceptionally high clustering coefficient. Technically, density is obtained by dividing the number of ties in a network by the number of all possible ties. The value ranges between 0 and 1, with higher values indicating denser networks and lower values indicating sparser networks. In real-world networks, the density varies depending on the size of a network; increasing the size of a network generally leads to a decrease in the density. The clustering coefficient is a network-level measure that illustrates the tendency of nodes to cluster in densely interconnected modules. This measure is to show the small-world property in which a network can be highly clustered even though it has a small average distance between nodes in spite of the large number of nodes. Therefore, high density in patent keyword network means that nodes in the patent keyword network are connected sporadically, and high clustering coefficient shows that nodes in the network are closely connected one another. Second, the cumulative degree distribution of the patent keyword network, as any other knowledge network like citation network or collaboration network, followed a clear power-law distribution. A well-known mechanism of this pattern is the preferential attachment mechanism, whereby a node with more links is likely to attain further new links in the evolution of the corresponding network. Unlike general normal distributions, the power-law distribution does not have a representative scale. This means that one cannot pick a representative or an average because there is always a considerable probability of finding much larger values. Networks with power-law distributions are therefore often referred to as scale-free networks. The presence of heavy-tailed scale-free distribution represents the fundamental signature of an emergent collective behavior of the actors who contribute to forming the network. In our context, the more frequently a patent keyword is used, the more often it is selected by researchers and is associated with other keywords or concepts to constitute and convey new patents or technologies. The evidence of power-law distribution implies that the preferential attachment mechanism suggests the origin of heavy-tailed distributions in a wide range of growing patent keyword network. Third, we found that among keywords that flew into a particular field, the vast majority of keywords with new links join existing keywords in the associated community in forming the concept of a new patent. This finding resulted in the same outcomes for both the short-term period (4-year) and long-term period (10-year) analyses. Furthermore, using the keyword combination information that was derived from the methodology suggested by our study enables one to forecast which concepts combine to form a new patent dimension and refer to those concepts when developing a new patent.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.1
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• pp.1-11
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• 2012

Purpose: The purpose of this study was to evaluate the bone regeneration capacity of silk fibroin (SF) when combined with beta tricalcium phosphate (${\beta}$-tricalcium phosphate [TCP]) and rh-bone morphogenetic protein (BMP) in vivo by micro-computed tomography (CT), soft x-ray, and histological analysis. Methods: A total of 56 critical size defects formed by a trephine bur made on 28 adult female Spague-Dawley rats were used for this study and the defect size was 5.0 mm in diameter. The defects were transplanted with (1) no graft material (raw defect), (2) autogenous bone, (3) SF ($10{\mu}g$), (4) SF-BMP ($10{\mu}g$, $0.8{\mu}g$ each), and (5) SF+${\beta}$-TCP ($10{\mu}g$). At 4 and 8 weeks after operation, the experimental animals were sacrificed. Samples were evaluated with soft x-ray, histological examinations and 3-dimensional micro-CT analysis. Results: In the 3-dimensional micro-CT evaluation, bone volume and bone surface data were higher in the SF-BMP ($12.8{\pm}1.5$, $138.6{\pm}45.0$ each) (P<0.05) and SF-TCP ($12.3{\pm}1.5$, $144.9{\pm}30.9$ each) group than in the SF group ($6.1{\pm}3.3$, $77.2{\pm}37.3$ each) (P<0.05), except for the autogenous group ($15.0{\pm}3.0$, $190.7{\pm}41.4$ each) at 4 weeks. At 8 weeks, SF-BMP ($16.8{\pm}3.5$, $173.9{\pm}34.2$ each) still revealed higher (P<0.05) bone volum and surface, but SF-TCP ($11.3{\pm}1.5$, $1132.9{\pm}52.1$ each) (P=0.5, P=0.2) revealed the same or lower amount compared with the SF group ($13.8{\pm}2.7$, $127.5{\pm}44.8$ each). The % of bone area determined by radiodensity was higher in the SF-TCP ($31.4{\pm}9.1%$) and SF-BMP ($36.2{\pm}16.2%$) groups than in the SF ($19.0{\pm}10.4$) group at the period of 4 weeks. Also, in the histological evaluation, the SF-BMP group revealed lower inflammation reaction, lower foreign body reaction and higher bone healing than the SF group at postoperative 4 weeks and 8 weeks. The SF-TCP group revealed lower inflammation at 4 weeks, but accordingly, as the TCP membrane was absorbed, inflammatory and foreign body reaction are increased at 8 weeks. Conclusion: The current study provides evidence that the silk fibrin can be used as an effective grafted material for tissue engineering bone generation through a combination of growth factor or surface treatment.

• Radiation Oncology Journal
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• v.8 no.1
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• pp.85-93
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• 1990

A series of 25 patients with residual, recurrent, and unresectable gastric cancer received various combination of surgery, radiotherapy (RT), chemotherapy (CT), and hyperthermia (HT). They were placed into 7 categories; 1) CT and HT-14 patients; 2) RT and HT-15 patients; 3) surgery, RT and HT-2 patients; 4) surgery, RT, HT and CT-1 patient; 5) RT, HT and CT -1 patient; 6) RT and CT-1 patient; 7) RT alone-1 patient. Three patients had curative resection. 21 patients received irradiation with tightly contoured portals to spare as much small bowel, kidney and marrow as possible. Hyperthermia was applied regionally once or twice a week for 23 patients using 8 MHz radiofrequency capacitive heating device (Thermotron RF-8). HT was given approximately 30 min after RT 7 patients were treated with CT: 4 patients received HT and concomitant Mitomycin-C; 3 patients received HT and sequential 5-FU+Adriamycin+Mitomycin-C. There was not any treatment related deaths. There was also no evidence of treatment related problems with liver, kidney, stomach, or spinal cord except only one case of transient diabetic ketoacidosis. The tumor response was evaluable in 22 patients. None achieved complete remission.11 ($50\%$) achieved partial remission. The response rate was correlated with total radiation dose and achieved maximum temperature. 9 of 14 ($64\%$) received more than 4000 cGy showed partial remission; especially, all 3 patients received more than 5500 cGy achieved partial response.8 of the 12 patients ($67\%$) who achieved maximal temperature more than $41^{\circ}C$ showed partial response in comparing with $25\%$ (2 of 8 patients, below $41^{\circ}C$). The numbers of HT, however, was not correlated with the response. 3 of the 25 patients ($12\%$) remain alive. The one who was surgically unresectable and underwent irradiation alone is in progression of the disease with distant metastases. The remaining two patients with curative resection are alive with free of disease, 24 and 35 months, respectively. The median survival by response are 11.5 months in responders and 4.6 months in non-responders.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.979-984
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• 2006

Although iron is essential for many physiological processes, excess iron can lead to tissue damage by promoting the generation of reactive oxygen species (ROS). There is increasing evidence that ROS might play an important role in the pathogenesis of cardiovascular disease. However, the effects of iron excess on platelet function and the thrombotic response to vascular injury are not well understood. We examined the effects of iron excess-induced oxidative stress and the antioxidants on platelet aggregation. Oxidative stress was accessed by either free iron $(Fe^{+2})$ or hydrogen peroxide $(H_2O_2)$, as well as their combination on washed rabbit platelets (WPs) in vitro. When WPs were stimulated with either $Fe^{+2}$ alone or a subthreshold concentration of collagen, which gave an aggregatory curve with a little effect, and a dose dependent increase in platelet aggregation was observed by increasing concentrations of $Fe^{+2}$ with $H_2O_2$. This aggregation was associated with the iron-catalyzed formation of hydroxyl radicals from $H_2O_2$, and were inhibited by NAD/NADP (proton acceptor), catalase $(H_2O_2\;scavenger)$, tiron (iron chelator), mannitol (hydroxyl radical scavenger), and indomethacin (cyclooxygenase inhibitor), but not by NADH/NADPH (proton donor), superoxide mutase, and aspirin. However, NADH/NADPH, an essential cofactor for the antioxidant capacity by the supply of reducing potentials, showed the effect of an enhanced radical formation, suggesting a role for NADH/NADPH-dependent oxidase. These results suggest that iron $(Fe^{+2})$ can directly interact with washed rabbit platelets and this aggregation be mediated by OH formation as in the Fenton reaction, inhibited by radical scavengers.