• Journal of Radiation Protection and Research
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• v.28 no.3
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• pp.233-237
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• 2003

It has been known that ATM plays a central role in response of cells to ionizing radiation by enhancing DNA repair. We have investigated the feasibility of increasing radiosensitivity of tumor cells with the use of ATM inhibitors such as caffeine, pentoxifylline and wortmannin. Human colorectal cancer RKO.C cells and RKO-ATM cells (RKO cells overexpressing ATM) were used in the present study. The clonogenic cell survival in vitro indicated that RKO-ATM cells were markdely radioresistant than RKO.C cells. Treatment with 3 mM of caffeine significantly increased the radiosensitivity of cells, particulary the RKO-ATM cells, so that the radiosensitivity of RKO.C cells and RKO-ATM cells were almost similar. The radiation induced G2/M arrest in RKO-ATM cells was noticeably longer than that in RKO.C cells and caffeine treatment significantly reduced the length of the radiation induced G2/M arrest in both RKO.C and RKO-ATM cells. Pentoxifylline and wortmannin were also less effective than caffeine to radiosensitize RKO.C or RKO-ATM cells. However, wortmannin was more effective than caffeine against human lung adenocarcinoma A549 cells indicating the efficacy of ATM inhibitor to increase radiosensitivity is cell line dependent. For in vivo study, RKO.C cells were injected s.c. into the hind-leg of BALB/C-nuslc nude mice, and allowed to grow to 130mm3 tumor. The mice were i.p. injected with caffeine solution or saline and the tumors irradiated with 10 Gy of X-rays. The radiation induced growth delay was markedly increased by 1-2 mg/g of caffeine. It was concluded that caffeine increases radiosensitivity of tumor cells by inhibiting ATM kinase function, thereby inhibiting DNA repair, that occurs during the G2/M arrest after radiation.

• Journal of The Korean Association For Science Education
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• v.38 no.3
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• pp.407-417
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• 2018

The purpose of this study is to analyze the roles of classroom activities in science lessons and student learning motivation in achieving students' scientific competencies, and to suggest implications for science lessons to develop scientific competencies. For this, based on the PISA 2015 data of Korean high school students, we analyzed how classroom activities in science influenced students' scientific competencies through learning motivation variables. As a result of the path analysis, the activities emphasizing interaction and a link to real life predicted intrinsic motivation, instrumental motivation, and science efficacy significantly. On the other hand, the activities that emphasize the student-led inquiry process did not show any effect on learning motivation. In addition, the higher the motivation to learn the science, the higher their scores in three scientific competencies: explaining phenomenon scientifically, evaluating and designing scientific inquiry, and interpreting data and evidence scientifically. The practices of school science lessons indirectly influenced the achievement of scientific competence through learning motivation. Specifically, the activities emphasizing interaction influenced achieving scientific competencies through intrinsic motivation, and the activities emphasizing linkage to real life influenced it through all learning motivation variables. Finally, we discussed some implications for the roles and practices of school science class for enhancing students' scientific competencies.

• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.4
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• pp.257-274
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• 2001

To properly prepare teeth, dentists require a direct view of the working area and are often placed in a difficult position, moreover, a high proportion of dentists suffer from headache and back pain. Dentists who make use of the dental mirror and position their patients carefully to gain a proper view report less headache, pain and discomfort in the shoulders. It is recommended that dentists learn the "Home Position(H.P.)" which among the various "Random Position(R.P.)" methods, enables dentists to approach their patients in a stable posture. The purpose of this study was to compare tooth preparation in the H.P. and the R.P., and evaluate the clinical efficacy of the H.P.. Tooth preparation for a full cast crown was performed on the maxillary left 1st molar using the H.P. and the R.P., and the shapes of the prepared tooth surfaces at the two different operating positions were compared. The amount of occlusal reduction, marginal width, height, and axial taper were measured and analyzed. A T-test was performed separately to compare the results of the H.P. and the R.P. with respect to the accuracy of the corresponding tooth reduction. The results were as follows. ; 1. The amount of occlusal reduction was excessive on the mesiobuccal cusp(P<0.05), and deficient on the lingual cusp in the H.P.(P<0.01). In the R.P., this was excessive on the buccal cusp and deficient on the fossa and distolingual cusp(P<0.01). 2. The amounts of marginal width were excessive in all areas except on the lingual and mesial surfaces in the H.P. and lingual surface in the R.P.(P<0.01). 3. The marginal heights were achieved more accurately in the R.P. than the H.P.(P<0.01). 4. Axial surface taper was excessive in all areas in the H.P.(P<0.01). But the axial taper of measured areas was even, and tooth is more like to retain its original axis after reduction. In the R.P., axial surface taper was excessive on the mesial and buccal area, and deficient on the distolingual area(P<0.01), and therefore, the axis of the prepared teeth was tipped in the distolingual direction. 5. The times needed for preparation were 12 minutes and 49 seconds in the H.P., and 11 minutes and 35 seconds in the R.P., and the R.P. was statistically faster(P<0.01). The tooth preparation in the H.P. achieved its goal, in that it enabled the operator to make even tooth reduction. In conclusion, the H.P. system offers an improved method that can be used in clinic after specific training.

• The Journal of Korean Academic Society of Nursing Education
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• v.2
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• pp.56-74
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• 1996

In order to prepare for the coming twenty-first century and to meet changing social demands and health needs, it is necessary to improve the curriculum through development of new conceptual frameworks. The purposes of this study were : 1) to assess the needs of the curriculum of the students, the faculty, the graduates, and the nursing supervisors and head murses ; 2) to develop the conceptual framework which includes philosophy and goals of nursing education based upon needs assessment ; 3) to develop level objectives ; 4) to identigy the contents of the curriculum ; 5) and to develop the faculty. The curriculum was assessed and developed from April, 1995 to March, 1996 through twenty four weekly meetings, two seminars, and two workshops. The process and results of this study are as follows : 1. A needs assessment of the present curriculum was done of the 194 students, 177 graduates, 14 faculty members, and 60 nursing administrators in 5 main areas (objectives, planning and organization, teaching-learning process and methods, evaluation, revision of curriculum). The results showed that there were many descrepancies between expectations and actual situations in all the groups and in all the areas. This implies that there was a necessity for total curriculum revision. 2. To develop the conceptual framework, 1) the core concepts were identified(man, health, environment, and nursing) on the basis of the existing educational philosophy and educational objectives of our school, elicited by group discussions using the nominal group method, one of the needs assessment methods, the philosophy and objectives were restated. 2) Six essential componednts were indentified for the conceptual framework from the restated philosophy and objectives ; nursing process, communication, professional roles, client, health, and nursing. The vertical theread consists of the client and health/nursing ; and the horizontal thread consists of nursing process, communication, and professional roles. 3. The contents of the curriculum were selected on the basis of the educational objectives and organized according to the conceptual framework. 4. The level objectives were then restated. It is expected that the objectives of our school will be accomphished through developing the courses, choosing and Implementing, more effective teaching-learning methods, and evaluating the efficacy of changes implemented. The most important factor will be to continually upgrade the faculty and their teaching skills.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.815-821
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• 1997

Background : Salmeterol, a new ${\beta}_2$-adrenergic receptor agonist, is a long-acting bronchodilator and benefits patients with asthma who have nocturnal symptoms. We wished to assess the efficacy of inhaled salmeterol ($50{\mu}g$ bid) compared to inhaled salbutamol ($200{\mu}g$ qid) for the treatment of bronchial asthma, particularly nocturnal asthma. Method : We randomly assigned 35 patients (25 female and 10 male patients, 15 to 50 years old) to one of two treatment groups : one group received $50{\mu}g$ of salmeterol twice daily and another did $200{\mu}g$ salbutamol four times per day. And this study was performed as an open-label and the 6 weeks inhalation period. Results : Analysis of symptam score ; Day and night time symptom score showed significant difference between salmeterol and salbutamol Group (p<0.05). Number of days for additional bronchodilator requirements; The number of days and puffs for additional bronchodilator were lower in the salmeterol group in either day and night time (p<0.05). Pulmonary function test ; $FEV_1$ showed significant increase in salmeterol group compared to salbutamol group after 2 and 4 weeks inhalation period. Adverse effects ; We found no evidence of tolerance to the bronchodilating effects of salmeterol, and adverse reactions to all the treatments were infrequent and mild. Conclusion : For the management of bronchial asthma, salmeterol given twice daily is superior to salbutamol given four times daily.

• Tuberculosis and Respiratory Diseases
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• v.61 no.4
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• pp.339-346
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• 2006

Background: There has no known epidemiologic survey on the frequency of complementary-alternative medicine (CAM) use in the treatment of adult asthma in Korea. This study examined the current use of CAM by asthma patients in Korea. Methods: One hundred adults with asthma, who had been admitted to Kyunghee university hospital between January 2000 and December 2003, were enrolled in this survey. They received a structured questionnaire interview and a clinical assessment of prevalence and pattern of CAM use. Results: 53% patients had an experience of at least one type of CAM during their asthma management. Users of CAM had more hospital visits than those who had never used CAM($1.46{\pm}0.68$ vs. $2.11{\pm}1.20$, p=0.001). Those in their $50^{th}$ decades had more experience of CAM (80%) than the other age groups. The methods of CAM used by our patients are as follows: Diet/nutritional therapy in 35 patients(69%), herbal therapy in 28 patients(53%), acupuncture in 9 patients(17%), moxa treatment in 6 patients(11%), breathing exercises in 1 patient(2%). Conclusions: More than 50% of patients with bronchial asthma have used CAM. A more detailed and large scaled study will be needed to define the actual status of the use of CAM in the treatment for asthma. Inaddition, further research on the scientific validation of the clinical efficacy of CAM in asthma management should be followed.

• Tuberculosis and Respiratory Diseases
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• v.68 no.1
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• pp.6-9
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• 2010

Background: The efficacious use of interventional bronchoscope for patients with central airway obstruction due to malignant or benign lesions has been proven. Among many therapeutic bronchoscopic procedures, endobronchial cryotherapy is an established recanalization method for the obstruction of the respiratory tract. Recently, the use of this procedure has been increasing in Korea. However, limited data are available in the literature regarding its efficacy in Korea. Methods: Thirty patients, who had been treated with a flexible cryoprobe for cryotherapy were enrolled; clinical characteristics and treatment outcomes were analyzed. The patients had been treated with the technique using nitrous oxide as a cryogen under local anesthesia. Objective outcomes were 3 different degrees of therapeutic success by use of follow-up bronchoscopic findings as follows: successful, partially successful, and unsuccessful response. Subjective outcomes were evaluated as an improvement in symptoms. Results: The mean age of enrolled patients was $59{\pm}11$ years and there was a male (22/30) dominance. Twenty-three patients had malignant tumor and 7 patients had benign lesions with central airway obstruction. Successful recanalization was achieved in 11 (37%) patients, and partially successful response was achieved in 15 (50%) patients. Dyspnea was improved in 84.2% (16/19) of patients. At least one respiratory symptom was resolved in 91.3% (21/23) patients. Seven patients (23.3%) needed additional bronchoscopic electrocautery because of the bleeding as a complication of cryotherapy. Conclusion: Endobronchial cryotherapy is an effective and less expensive procedure for the management of central airway obstruction. However, the procedure should be performed under the preparing for an emergency situation, such as massive bleeding.

• Journal of Technologic Dentistry
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• v.31 no.1
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• pp.55-61
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• 2009

Passive fitting of meso-structure and super-structures is a predominant requirement for the longevity and clinical success of osseointegrated dental implants. However, precision and passive fitting has been unpredictable with conventional methods of casting as well as for corrective techniques. Alternative to conventional techniques, electro discharge machining(EDM) is an advanced method introduced to dental technology to improve the passive fitting of implant prosthesis. In this technique material is removed by melting and vaporization in electric sparks. Regarding the efficacy of EDM, the application of this technique induces severe surface morphological and elemental alterations due to the high temperatures developed during machining, which vary between $10,000{\sim}20,000^{\circ}C$. The aim of this study was to investigate the morphological and elemental alterations induced by EDM process of casting dental gold alloy and non-precious alloy used for the production of implant-supported prosthesis. A conventional clinical dental casting alloys were used for experimental specimens patterns, which were divided in three groups, high fineness gold alloy(Au 75%, HG group), low fineness gold alloy(Au 55%, LG group) and nonprecious metal alloy(Ni-Cr, NP group). The UCLA type plastic abutment patterns were invested with conventional investment material and were cast in a centrifugal casting machine. Castings were sandblasted with $50{\mu}m\;Al_2O_3$. One casting specimen of each group was polished by conventional finishing(HGCON, LGCON, NPCON) and one specimen of each group was subjected to EDM in a system using Cu electrodes, kerosene as dielectric fluid in 10 min for gold alloy and 20 min for Ni-Cr alloy(HGEDM. LGEDM, NOEDM). The surface morphology of all specimens was studied under an energy dispersive X-ray spectrometer (EDS). The quantitative results from EDS analysis are presented on the HGEDM and LGEDM specimens a significant increase in C and Cu concentrations was found after EDM finishing. The different result was documented for C on the NPEDM with a significant uptake of O after EDM finishing, whereas Al, Si showed a significant decrease in their concentrations. EDS analysis showed a serious uptake of C and Cu after the EDM procedure in the alloys studied. The C uptake after the EDM process is a common finding and it is attributed to the decomposition of the dielectric fluid in the plasma column, probably due to the development of extremely high temperatures. The Cu uptake is readily explained from the decomposition of Cu electrodes, something which is also a common finding after the EDM procedure. However, all the aforementioned mechanisms require further research. The clinical implication of these findings is related with the biological and corrosion resistance of surfaces prepared by the EDM process.

• CELLMED
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• v.3 no.3
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• pp.24.1-24.5
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• 2013

Pharmacopuncture, or herbal acupuncture, is a new form of therapy derived from combinations of two traditional therapeutic methods, herbal medicine and acupuncture therapy. To compare the efficacy between dexamethasone-pharmacopuncture (DP) and dexamethasone-oral administration (DO), the effect of DP was investigated in murine models. Anti-anaphylactic effects of dexamethasone treatments were investigated in compound 48/80-induced systemic anaphylactic reaction, ear swelling response, and passive cutaneous anaphylaxis (PCA). DP treatment significantly inhibited the compound 48/80-induced systemic anaphylactic reaction, ear swelling response, and PCA. The effects between DP and DO were on a similar level. These results indicate that DP can be used as an alternative method for DO in case of emergency.

• Journal of Aquaculture
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• v.18 no.4
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• pp.272-279
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• 2005

The efficacy of lidocaine hydrochloride and Clove oil as anaesthetics was evaluated in the Korean rose bitterling, Rhodeus uyekii (Mori, 1935) and oily bitterling, Acheilognathus koreensis (Kim and Kim, 1990) at four different temperatures of $10^{\circ}C,\;15^{\circ}C,\;20^{\circ}C$ and $25^{\circ}C$. When complete anaesthesia was acquired less than 3 min and recovery was acquired less than 10 min, the optimal dose range of lidocain hydrochloride at $20^{\circ}C$ was 250${\~}$550 ppm in Korean rose bitterling, and 150${\~}$550 ppm in oily bitterling, respectively. In case of Clove oil, the optimal dose range at $20^{\circ}C$ was 40${\~}$200 ppm in Korean rose bitterling and 80${\~}$240 ppm in oily bitterling, respectively. Both of lidocaine hydrochloride and Clove oil resulted in a negatively dose-dependent manner for anaesthesia induction time in these two species. Recovery times were more variable in relation to anaesthetic doses, but in general higher anaesthetic doses resulted in similar or longer recovery time. As expected, the lower temperature resulted in longer anaesthesia induction and recovery time. The study demonstrated that lidocaine hydrochloride and Clove oil can be used as effective anaesthetics in these two species. The results from this study could be useful for aquaculturists industry and other related husbandry practices that require anaesthesia of Korean rose bitterling and oily bitterling.