• Korean Journal of Organic Agriculture
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• v.27 no.3
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• pp.365-380
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• 2019

Total of 20 Holstein calves of 10 calves (3.90±0.26 month of age) born in spring (S) and 10 calves (4.10±0.30 month of age) born in fall (F) were reared in this study for 24 months and diets were divided into separate feeding of forage and concentrates (C) and TMR (T). Therefore, 4 treatments in this study were composed of CS, CF, TS and TF with the factors of diets and calving season. After parturition of heifers, all animals were fed the same diet and milk production was recorded monthly. DM intakes in growing period were influenced by calving season, and those of the animals calved in fall were higher than in those calved in spring (P<0.01), but there were no significant differences by feeding method. CP intakes and TDN intakes were significantly influenced by calving season (P<0.05) and feeding method (P<0.001), and the animals calved in fall were about 1.2% higher than those calved in spring, and the animals fed TMR were about 4.7% higher than those fed concentrates and forage separately. Average, 9th and 10th months' milk yields were significantly influenced by feeding method in which those in the treatments fed TMR (TS, TF) were higher than in separate feeding of concentrates and forage (CS, CF; average P<0.05; 9th and 10th months P<0.01). Average milk persistency was also significantly influenced by calving season (P<0.05) and feeding method (P<0.01) and those in the animals calved in fall were higher than in spring and those of the TMR fed animals were also higher than in separate feeding of concentrates and forage. Milk persistency was similar to the results of milk yield, showing statistically significant differences affected by the feeding method at 9th and 10th months of late lactation (P<0.01), and it was about 8% higher in the animals fed TMR, showing higher tendency at 7th (P=0.12) and 8th months of late lactation (P=0.09). Therefore, it is expected that postpartum milk yield and milk persistency would be higher when the hiefers are fed TMR in growing period and calved in fall. Average milk fat content was influenced by feeding method. Milk fat content of the animals fed TMR during growing period were 7.8% higher than those fed concentrates and forage separately (P<0.01). This suggests that feeding TMR during growing period influenced first postpartum eating behavior, which stabilized the rumen and resulted in the increased milk fat. At 3rd month after calving, milk fat content was lower in the animals calved in spring than in those calved in fall, suggesting that it might have been influenced by the seasonal differences. MUN showed significant differences by feeding method in which those in separate feeding of concentrates and forages were higher especially in average, 4th, 5th and 6th months (average and 4th P<0.01; 5th and 6th months P<0.05). SCC was higher in the animals fed TMR than in those fed concentrates and forage separately especially in average, 3rd and 4th months after calving (P<0.01). In conclusion, when feeding TMR during growing period and calving in fall, it was not influenced by the high temperature in summer, and it resulted in the improved milk yield, milk persistency and milk fat content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.147-154
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• 1969

The larvae of the ark shell Anadare broughtoni(Schrenck) were grown at room temporature (approximately $20.4^{\circ}C$), and fed laboratory-cultured Cyclotella nana. The egg of the ark shell produced in the laboratory measured about $54.9\mu$ in diameter. The embryos gradually developed into larvae up to $110.8\mu$ shell length, $83.9\mu$ shell height and with shell breadth of $58.2\mu$ even in the absence of the algal food. Beyond this sire, however, the growth of the larvae was considerably retarded. The larvae showed better growth rate when they were fed the algal food two days after spawning, i. e., early straight-hinge stage. Daily rate of food consumption varies according to the larval sizes. But the rate increases considerably when the larvae begin to form umbos. In general the rate Is indicated by the following formula: $Y=0.0025161\;X^{2.76459}$. The growth experiments of the larvae indicate that the efficiency of food conversion was higher when fed centrifuged food. Regarding to the difference in the slopes of growth curve, centrifuged food showed better growth rate as compared to those grown with the non-centrifuged food. The smaller the larval size, the greater will be the difference in growth. The larvae began settling when they reathed 261.7 to $289.6\;{\mu}$ in shell length, 199.2 to $221.7\mu$ in shell height and 147.6 to $170.8\mu$ in shell breadth. The time which elapsed from spawning to the larval settlement was about 28 days. The mean growth of the larvae is indicated with regression line and exponential curve equations as follows. Regression line shell length. 94.3 to $133.9\mu$ : Y==85.22857+3.35000X 141.6 to $269.3\mu$: Y=10.83036X-36.05357 296.8 to $373.2\mu$ : Y=19.10000X-279.30000 shell height: 72.7 to $89.7\mu$ : Y=67.11429+2.15714X 108.4 to $206.4\mu$ : Y=8.31607X-27.45357 228.6 to $282.1\mu$: Y=173.46700+13.37500X shell breadth: 45.3 to $77.8\mu$ : Y=38.08510X+2.73570X 87.4 to $157.7\mu$: Y=5.77320X-5.99640 175.4 to $214.0\mu$: Y=19.65000X-114.13300 Exponential curve shell length. 94.3 to $373.2\mu$: Y=72.45 $e^{0.04697x}$ shell height: 72.7 to $282.1\mu$: Y=54,96 $e^{0.04720x}$ shell breadth: 45.3 to $214.0\mu$ : Y=39.82 $e^{0.04927x}$ The relationships between the shell length and shell height and between the shell length and shell breadth are indicated as follows- shell height: 72.7 to $98.7\mu$ : Y=12.87780+0.63817X 108.4 to $206.4\mu$ : Y=0.90220+0.76456X 228.6 to $282.1\mu$ : Y=25.02630+0.69156X shell breadth: 45.3 to $77.8\mu$:Y=0.81373Xx-31.18914 87.4 to $157.7\mu$ : Y=13.37549+0.53230X 175.4 to $214.0\mu$: Y=30.24328+0.49545X

• Clinical and Experimental Pediatrics
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• v.48 no.3
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• pp.266-275
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• 2005

Purpose : Acute respiratory tract infections are the most common illnesses in children. The great majority of these infections involving lower respiratory tracts infections(LRTIs) are caused by respiratory viruses such as respiratory syncytial virus(RSV), parainfluenza virus(PIV), influenza virus (Flu), and adenovirus(ADV), etc. Our purpose was to determine seasonal epidemiology and clinical characteristic features of each viral infection. Methods : Nasopharyngeal aspirate(NPA)s were collected from 4,554 hospitalized children diagnosed as LRTIs on the first day of admission. The study period was from September 1998(Autumn) through May 2003(Spring). Respiratory viruses were detected in 881(19 percent) cases by isolation of the virus or by antigen detection method using indirect immunofluorescent staining. We reviewed the medical records of 837 cases retrospectively. Results : The identified pathogens were RSV in 485 cases(55 percent), PIV in 152 cases(17 percent), FluA in 114 cases(13 percent), ADV in 79 cases(9 percent) and FluB in 51 cases(6 percent). Outbreaks of RSV occurred every year, mostly in the November through December period and of PIV in the April through June period. LRTIs by FluA reached the highest level in January, 2002. FluB infection showed an outbreak in April, 2002. The clinical diagnoses of viral LRTIs were bronchiolitis in 395 cases(47 percent), pneumonia in 305 cases(36 percent), croup in 73 cases(9 percent) and tracheobronchitis in 64 cases(8 percent). Conclusion : Viruses are one of the major etiologic agents of acute LRTIs in chidren. Therefore, we must continue to study their seasonal occurrence and clinical features to focus on management, and also for reasons of prevention.

• The korean journal of orthodontics
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• v.27 no.2
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• pp.221-230
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• 1997

It has been known that head posture may influence directly and/or indirectly the growth and development of craniofacial morphology and can also be influenced by the funtional demand of physiologic activity. It was reported that facial morphology has close relationships with hyoid bone position and head posture. In many previous studies, Natural Head Posture(NHP) was guided, and also it was shown that NHP has high degree of reproducibility. Otherwise, There was few study about the relationship of head posture, with routine cephalometric film which is used for clinical orthodontic purpose. In this study, according to the Wits and ANB of initial cephalometric film which was taken with vertical pendulum as representative of true vertical reference line. We classified the subjects which is comprised of 60 adult female patients into Class I, II, III (Cl I, II, III)and we tried to find out the correlation of head posture and hyoid bone position according to the classification of malocclusion. As a result of our research, we found the followigs. 1. In comparison of vertical position of hyoid bone relative to the cranial base. the position of hyoid bone of Cl III was lower than that of Cl II. 2. In comparison of anteriorpostes or position of hyoid bone, relative to the cervical column. The position of hyoid bone of Cl III was more anterior than that of a II 3. in comparison of vertical position of hyoid bone relative to mandible. There was no significant correlation aumoug the groups of malocclusion. 4. ANB and Wits showed no significant correlation with hyoid bone position. 5. The relative extension of head, which was noted in Cl II, showed negative with Sum, ANB. 6. In Cl II and Cl III, Post to Ant facial height showed positive correlation with NSL/VER.

• Parasites, Hosts and Diseases
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• v.30 no.2
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• pp.113-124
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• 1992

Protective effects of monoclonal antibodies against n. fowleri were comparatively studied. nALB/c mice were treated with two types of monoclonal antibodies, Nf 2 and Nf 154, before and after the infection with N. fowleri. The mortality and mean survival times were then compared. Also, direct effect of the monoclonal antibodies on the N. fewleri trophozoites in vitro were observed. In vitro protective effects of the monoclonal antibodies were also studied in cells infected with N. fowleri. The observed results are summarized as follows: 1. Among mice pretreated twice before the infection with monoclonal antibody Nf 2 (McAb Nf 2), only 15.8% were killed, and the mean survival time was 17, 7 days. This was not much different from the mice pretreated once, as the mortality and mean survival time were 16.7% and 17 days. Those effects were compatible with monoclonal antibody Nf 154 (McAb Nf 154). The above findings contrast with the mortality and mean survival time of the control mice, which were 22.7% and 14.6 days respectively. 2. Mice which received twice the McAb Nf 2 following N. fowleri infection incurred a 19.4% mortality rate with 13.6 days survival time; 17.9% and 15.8 days with on time administration, in contrast to the 25% and 14.6 days in the control group. 3. Marked agglutination effect of McAb Nf 2 or McAb Nf 154 were observed on n. fowkwi, trophogoites. 4. When N, fowleri trophozoites were treated with McAb Nf 2 or McAb Mf 154 combined with comments, the proliferation rate was more significantly suppressed than in that the control, 5. N. fowleri trophozoites treated with McAb Nf 2 or McAb Nf 154 showed an increased number of swollen mitochondria, disfigured cisternal, lipid droplets, and osmiophilic granules in the cytoplasm. 6. A remarkable protective effect of monoclonal antibodies was noticed in CHO cells infected with N. fowleri. More than 90.6% of the infected CHO cells survived, contrasted with 27% of untreated cells. The overall results in this study suggest that N. fewleri treated with monoclonal antibodies against N. fowleri reduce the mortality and prolong the survivial time of the mice when the antibodies are administered before the infection. The protective effect of the monoclonal antibodies is surmised being caused by agglutination of the trophozoites.

• Reproductive and Developmental Biology
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• v.35 no.1
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• pp.33-45
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• 2011

Heat shock protein 90 (Hsp90) is ATPase-directed molecular chaperon and affects survival of cancer cell. Inhibitory effect of Hsp90 by inducing cell cycle arrest and apoptosis in the cancer cell was reported. However, its role during oocyte maturation and early embryo development is very insufficient. In this study, we traced the effects of Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), on meiotic maturation and early embryonic development in pigs. We also investigated several indicators of developmental potential, including structural integrity, gene expression (Hsp90-, cell cycle-, and apoptosis-related genes), and apoptosis, which are affected by 17-AAG. Then, we examined the roles of Hsp90 inhibitor on viability of primary cells in pigs. Porcine oocytes were cultured in the NCSU-23 medium with or without 17-AAG for 44 h. The proportion of GV arrested oocytes was significantly different between the 17-AAG treated and untreated group (78.2 vs 34.8%, p<0.05). After completion of meiotic maturation, the proportion of MII oocytes was lower in the 17-AAG treated group than in the control group (27.9 vs 71.0%, p<0.05). After IVF, the percentage of penetrated oocytes was significantly lower in the 17-AAG treated group (25.2%), resulting in lower normal pronucleus formation (2PN of 14.6%). Therefore, the inhibition of meiotic progression by Hsp90 inhibitor played a critical role in fertilization status. Porcine embryo were cultured in the PZM-3 medium with or without 17-AAG for 6 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without 17-AAG. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 17-AAG treated group compared with control (7.5 vs 4.4, respectively). Blastocysts that developed in the 17-AAG treated group had low structural integrity and high apoptotic nuclei than those of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. The mRNA expressions of cell cycle-related genes were down-regulated in the 17-AAG treated group compared with control. Also, the expression of the pro-apoptotic gene Bax increased in 17-AAG treated group, whereas expression of the anti-apoptotic gene Bel-XL decreased. However, the expression of ER stress-related genes did not changed by 17-AAG. Cultured pESF cells were treated with or without 17-AAG and used for MIT assay. The results showed that viability of pESF cells were decreased by treatment of 17-AAG ($2{\mu}M$) for 24 hr. These results indicated that 17-AAG decreased cell proliferation and increased cell death. Expression patterns Hsp90 complex genes (Hsp70 and p23), cell cycle-related genes (cdc2 and cdc25c) and apoptosis-related genes (Bax and Bcl-XL) were significantly changed by using RT-PCR analysis. The spliced form of pXbp-1 product (pXbp-1s) was detected in the tunicamycin (TM) treated cells, but it is not detected in 17-AAG treated cells. In conclusion, Hsp90 appears to play a direct role in porcine early embryo developmental competence including structural integrity of blastocysts. Also, these results indicate that Hsp90 is closely associated with cell cycle- and apoptosis-related genes expression in developing porcine embryos.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.105-110
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• 1984

Seven seed samples of corn obtained from Kangweon Provincial Office of Rural Development, Kerea were tested for seed-borne fungi, and found that all the samples tested were infected with Fusarium moniliforme to an extent of $6.0{\sim}79.5%$. Severely infected seed samples showed poor germination on blotter. Seed component plating showed that the fungus present not only in tip caps, pericarps and endosperms, but also in embryos. Heavy infection of the fungus caused severe seed rot and seedling blight in soil, but the damage was not severe and many plants grew without any symptoms when the seeds with light infection were sown in soil. However the fungus was frequently detected from inside of the stems of healthy looking seedlings. The results indicate that the fungus transmit from seed to plant systemically. In inoculation experiments, the fungus produced stem rots on corn plants of 110 days old. The cultivar of Hwangok 3 was revealed more susceptible to the fungus than that of Suweon 19.

• Journal of Korean Academy of Nursing
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• v.7 no.2
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• pp.11-21
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• 1977

Many in nursing look back on Nursing Research history and proudly point to the fact that emphasis in nursing research has changed from studying the nurse to studying nursing practice. In recent years, much emphasis has been placed on seeking a method of evaluating the quality of nursing care. In spite of these attempts, however, an instrument for evaluating the quality of nursing care that is actually applicable in the clinical area has not been found. The Purposes of this study are as follows: 1) To develop the instrument to be used in evaluating the quality of nursing care provided in the Neuro - Surgery Constant Care Unit of Severance Hospital 2) To evaluate the quality of nursing care in the clinical area. 3) To provide the necessary information for improvement of quality of nursing care. The instrument for evaluating the quality of nursing care, developed by the investigator, was composed of 7 nursing goals and divided into 65 standards of nursing performance. The 7 nursing goal are as follows : 1) Maintenance of airway 2) Maintenance of fluid at electrolyte balance 3) Maintenance of elimination 4) Personal hygiene 5) Optimum activity 6) Prevention of accidents 7) Emotional care The study population defined was composed of all the case (51) who were admitted in the Neuro- Surgery Constant Care Unit of Severance Hospital from May 7-13, 1976. The observation method was used and the data was subjected to the %, X²-test, T-test, F-test and Correlation. The results of tile study were as follows : 1. Levels of nursing performance regarding nursing goals. Seven different nursing care indices were constructed in terms of nursing goals. The index scores were grouped arbitrarily into ,j categories such as "excellent", "good", "moderate", "incomplete", and "poor"based upon the investigator′s personal judgement. a. The nursing index of maintaining airway showed that 78% of the patients fell within the "excellent" and 22% of the patients, fell within the "good" category. b. The nursing index of maintaining fluid & electrolyte balance showed that 95% of the patients fell within the "excellent" and 5 % of the patients fell within the "good" category. c. The nursing index of maintaining elimination showed that 100% of the patients fell within the "excellent" category. d. The nursing index of personal hygiene revealed that 49% of the patients fell within the "excellent" and 51% of the patients fell within the "good" category. e. The nursing index of optimum activity showed that 63% of the patients fell within the "excellent" and 32% of the patients fell within tile "good" and 5% of patients fell within the "moderate" category. f. The nursing index of prevention of accidents showed that 100% of the patients foil within the "excellent" category. g. The nursing index of emotional cart revealed that 27% of the patients fell within the "excellent", 24 % of the patients fell within tile "good", 29 % of the patients fell within the "incomplete" category. From these findings it is disclosed that the quality of nursing care provided in the Neuro- Surgery Constant Care Unit of Severance Hospital was excellent. h. There were statistically significant differences between the nursing index of physical care and emotional care. (t=8.73, D. F. =100. p<0.01) It is revealed that more physical care then emotional care was carried out by nurses. 2. Levels of nursing performance regarding general characteristics of the patients. No significant differences were observed statistically with the nursing indices of nursing goals according to the sex (t=0.084, D. F. =12, p>0.05). Age (F=0.1251, D. F. : 3.18. p 〉0.05), absence or presence of operating experiences (t=0.6032, D. F. =12, p〉0.05, levels of consciousness (F=0.31, D. F. :3. 18, p >0.05) 3. Relationship between the levels of consciousness and the nursing index of each nursing goal. There was negative correlation between the levels of consciousness and the nursing index of maintaining airway (r=-0. 5449, p<0.01) and personal hygiene (r= -0.4075, p<0.01) There was positive correlation between the levels of consciousness and the nursing index of optimum activity (r=0.3936, p <0.01) and emotional care (r=0.7819, p〈0.01). There was slight correlation between the levels of consciousness and the nursing index of maintaining fluid & electrolyte balance (r=-0.3418, 0.010.05) and preventing accidents (r=0.1441, p>0.05.

• Journal of Korean Academy of Nursing
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• v.18 no.1
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• pp.26-33
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• 1988

내담자와 상담자간의 관계형성 추진에 관한 연구가 C. Rogers에 의해 시작된 이래, 돕는자 또는 상담자가 가져야 할 주요 조건으로서 공감, 존중, 온정, 확고부동함, 진지성, 자기노출, 직면반응 등을 들고 있으며 이중 둘 또는 세 요소 등을 선택하여 그 효과를 보고 있으나 역시 가장 주요한 요소로써는 공감을 들고 있다. 공감에 관한 연구는 그 본질의 정서적 측면, 인지적 측면 또는 복합적인 측면을 강조하면서 시도되고 있으나 간호원은 돕는자로써 환자의 문제해결을 위한 전수자적 역할을 해야한다는 점을 고려할때 간호현상에서의 공감에 관한 연구는 복합적인 측면을 강조하는 공감이 어 야 한다고 생각한다. 간호학자들도 간호원의 돕는 행위중 주요 요소로써 공감을 들고 있으며 특히 Lamonica는 공감측정을 위한 도구를 개발하였으며 공감이란 환자가 간호원이 환자의 입장을 이해하고 도와준다는 사실을 인지하고 그 고마움을 표현하는 것을 의미한다고 하였다. 본 연구자는 간호원-환자간의 촉진적 관계형성을 위한 교육내용 개발에 대한 기본 연구로써 한국인의 공감 정도를 측정할 수 있는 도구개발의 중요성을 느껴 Lamonica 의 공감측정 도구를 번역하게 되었다. 본 연구의 구체적인 목적은 미국문화권에서 사용되는 공감측정 도구가 한국인에게 적합하고 의미있게 번역되었는지를 확인하고 또한 한국인이 인지한 공감에 대한 탐색을 하는데 있다. 위 목적달성을 위하여 횡문화적 연구과정을 통한 개념분석, 도구 개발에 대한 통계분석을 시도하였다. 한국인의 공감 개념 분석을 위하여 미국 텍사스 오스틴에 있는 한국인에게 공감의 뜻, 동의어, 어떤 경우에 공감을 느꼈는지, 어떤 경우에 비공감적임을 느꼈는지를 물은 결과 한국인이 갖는 공감의 의미는 미국인의 것과 유사하지만 그 표현방법의 차이가 있음을 알게 되었다. 따라서 두 국가에서 사용되는 공감의 의미가 유사하고 또한 간호학자인 Lamonica가 개발한 공감측정 도구를 한국인에게 사용하는데 무리가 없을 것으로 판단되었다. 도구의 번역은 텍사스 주립대학 박사과정 지원생인 임상 심리 학자에게 의뢰하고 그 정확성을 판단하기 위해 인간을 대상으로 하는 학문을 연구하는 한국인(간호학, 사회학, 신문방송, 광고학, 심리학 전공)에게 그 정확성 유무를 물어 최고 27점, 최하 9점중 22점 미만인 문항에 대해서는 미국 간호학자와 의논하여 수정ㆍ보완하였다. 그 후 일반인으로 간주되는 한국인에게 그 도구의 이해 여부를 확인한 후 통계분석을 시도하였다. 대상자는 미국 텍사스 오스틴에 거주하면서 한국을 떠난지 3년 미만인 성인 45명을 대상으로 하였다. 2차에 걸친 자료수집 과정상 5명의 자료는 분석 불가능하다고 판단되어 총 40명의 자료를 spss- X를 이용하여 cronbach's alpha, test-retest stability, intercorrelation matrix 분석을 통한 결과는 다음과 같다. 1) cronbach's alpha는 1차 .9353 2차 .9666으로써 문항의 동질성을 보였고, 3, 4주 간격으로 행한 test-retest stability는 .7619(p＝000)이였다. 2) 반면에 intercorrelation matrix에서는 역관계 또는 무관계를 보였으며 84문항중 26문항의 item-to-total correlation값이 .35미만이었고 이 중 16문항은 .30 미만이었다. 이들을 제외한 68문항과 58문항의 각각의 item-to-total correlation간은 .96이었고 test retest stability 역시 .76으로써 84문항 전체에 관한 값과 유사하였다. 3) 역상관 또는 무상관의 값을 보인 문항을 미국 간호학자와 재검토한 결과 본래 문항에서의 단어 의미가 복합적이거나 불분명한 것이었고 또는 미국 문화권에서 사용되는 특이한 용어임을 알 수 있었다. 따라서 한국인 공감 측정 도구의 타당성을 높이기 위해 역통역을 시도하였다. 그후 공감에 관한 연구를 하고 있는 미국 학자에게 그 정확성을 판단하여 최종적으로 58문항이 한국인 공감측정 도구로서 적합하다는 판단을 하였다. 위 결과를 통한 결론 및 제언은 다음과 같다. 인간의 행위는 조건화된 문화권에 따라 다를 수 있으며, 이것은 같은 현상을 인지하는데도 영향을 미치게 되며 본 연구와 같이 어떤 현상에 대한 횡문화적 연구는 그 행위를 이해하는데 도움을 준다. 그러나 한국에서 간호에 대한 연구가 한국적 토착화 과정에 있으므로 그 연구 방법이나 도구사용이 서구의 것을 도입해야 하는 입장을 고려할 때 도구번역 과정은 원래의 의미나 함축성을 내포한 번역이어야 하며 소홀히 해서는 안될 과정임을 재확인되었다. 또한 추후 연구로써 다양한 계층의 다수를 대상으로 한 한국인 공감 측정 도구의 타당성을 재확인해야 하며 요인분석을 시도할 필요성이 있다고 사려된다.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.3
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• pp.746-763
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• 1996

An alternative design to conventional class II cavity preparation for proximal carious lesions is the tunnel preparation. It preserves the marginal ridge intact, thus making it possible to maintain the natural contact relationship with the adjacent tooth and minimize tooth reduction. This in vitro study was purposed to evaluate the effect of the materials' elastic constants and shear-bond strength on the marginal ridge fracture resistance of teeth restored by the tunnel technique, and to find the materials of choice for tunnel restorations. $Resinomer^{(R)}$, $Ketac-silver^{(R)}$, $Miracle-Mix^{(R)}$, and Tytin were used as restorative material. The elastic constants of each restorative material were evaluated by ultrasonic pulse measurement. Young's modulus and bulk modulus of the restorative materials were evaluated in three specimens for each material type. The shear-bond strength of the restorative materials to the dentin surface was measured after thermocycling 400 times between 6 and $60^{\circ}C$, using ten specimens for each material type. For measuring marginal ridge strength, 60 sound extracted molar teeth were distributed into six groups by size. Sound molar teeth were used as a Control group and unfilled prepared teeth were grouped as Unrestored. Another four groups were named Resinomer group, Ketac-Silver group, Miracle Mix group, and Tytin group by type of restorative material. Tunnel cavity preparation was done with ' 1/2, 2, and 4 round burs in sequence. Initial access to proximal surface was made through an occlusal access preparation started at least 2mm from the marginal ridge, and the proximal opening was formed about 2.5mm below the marginal ridge. After restoration and thermocycling, marginal ridge strength was measured using a universal testing machine. The results were as follows: 1. The Young's modulus of $Tytin^{(R)}$ was 63.95 GPa, followed by $Ketac-Silver^{(R)}$ 27.60 GPa, $Miracle-mix^{(R)}$ 18.48 GPa, and $Resinomer^{(R)}$ 10.74 GPa showing significant differences between the groups(P<0.05). The bulk modulus of the materials showed the same order as Young's modulus. The value of $Tytin^{(R)}$ showed 59.57 GPa indicating that it will deform less than other materials under the same stress. It was followed by $Ketac-Silver^{(R)}$ 23.57 GPa, Miracle $Mix^{(R)}$ 12.50 GPa, and $Resinomer^{(R)}$ 11.60 GPa. 2. The Resinomer group had a shear-bond strength of 7.41 MPa which was significantly higher than those of the Ketac-Silver group (1.80 MPa) and the Miracle Mix group (2.84 MPa) (P<0.01). All the specimens of Tytin group detatched from the dentin surface during thermocycling. 3. The mean marginal ridge strength of the Unrestored group(46.14 kgf) was significantly lower than that of the Control group (84.24 kgf) (P<0.01). The marginal ridge strength of teeth restored by the tunnel technique was, in order, Ketac-Silver group 74.06 kgf, Miracle Mix group 73.36 kgf, Resinomer group 63.47 kgf, and Tytin group 58.76 kgf. The Ketac-Silver, Miracle Mix, and Resinomer groups showed no significant difference with the Control group (P>0.05), but the Tytin group showed significantly lower strength compared to the Control group(P<0.05). The results showed that the marginal ridge strength of the teeth restored by the tunnel technique was not significantly lower than that of sound teeth. They also demonstrated that the bonding strength of the restorative material to the tooth surface should be high and the modulus of elasticity should not be lower than that of the tooth in order to restore the marginal ridge strength to its natural condition.