• The Journal of Korean Academy of Prosthodontics
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• v.38 no.6
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• pp.757-764
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• 2000

Statement of the problem. All-ceramic post-and-core restorations offer a number of advantages compared with systems that use metal build-ups. In certain clinical cases, however, fractures at the joint between the post and core build-up have been reported. Purpose. The objective, therefore, is to improve the joint between the post and the core build-up. Material and methods. Three different methods were used to prepare all-ceramic post-and-core restorations; pressing IPS Empress core build-ups to CosmoPost zirconia posts, cement-ing IPS Empress core build-ups to CosmoPost zirconia posts and Celay-milling of zirconia blanks. A series of ten restorations was prepared for each of the three methods. The post-and-core complexes were tested to failure with the load applied perpendicular to the post axis. The load and deflection at fracture were recorded. Results. The highest breaking load and highest deflection were recorded for the cementing technique with values of 25.3 N and $394{\mu}m$, respectively, The corresponding values for the pressed core build-ups and the milled zirconia core build-ups were 22 N and $301{\mu}m$, and 13 N and $160{\mu}m$, respectively. All the differences are statistically significant (p=0.05). Regarding the load-dependence of the deflection, the cemented core build-ups again demonstrated the highest value with $15.5{\mu}m/N$. The difference in the values of $13.6{\mu}m/N\;and\;13{\mu}m/N$ recorded for the pressed-on and milled core build-ups, respectively, were statistically insignificant. Conclusion. In regard to the high fracture resistance of zirconia post, adhesive cementing the core build-up to the post offers a viable alternative to the conventional pressing technique. The elastic bond between the rigid high-strength zirconia post and the core build-up presents an additional advantage.

• Journal of the Korean Ceramic Society
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• v.38 no.11
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• pp.973-979
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• 2001

Tin-doped indium oxide (ITO) thin films were deposited using r.f. magnetron reactive sputtering and the electrical properties, such as the resistivity, carrier concentration and mobility, were investigated as a function of the sample position under a given magnetron sputtering condition. The nonhomogeneity of the electrical properties with the sample position was observed under a given magnetron sputtering condition. The resistivity of ITO thin film on the substrate which corresponded to the center of the target had a minimum value, 2∼4$\times$10$\^$-4/$\Omega$$.$cm, and it increased symmetrically when the substrate deviated from the center. The density measurement result also showed that ITO thin film deposited at the center has a maximum density of 7.0g/cm$^3$, which was a relative density of about 97%, and the density decreased symmetrically as the substrate deviated from the center. The nonhomogeneity of electrical properties with the deposition position could be explained with the incidence angle of the source beam alpha, which is related with an atomic self-shadowing effect. It was confirmed experimentally that the density in film affect both the carrier mobility and the conductivity. In the case where the density of ITO thin film is 7.0g/cm$^3$, the magnitude of the mean free path was identical with that of the grain size(the diameter of column). However, in the other cases, the mean free path was smaller than the grain size. These results showed that the scattering of the free electrons at the grain boundary is the major factor for the electrical conduction in ITO thin films having a high density, and there exists other scattering sources such as vacancies, holes, or pores in ITO thin films having a low density.ing a low density.

• Korean Journal of Agricultural Science
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• v.6 no.1
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• pp.21-26
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• 1979

To compare the effect of dikegulac (sodium 2,3 : 4, 6-di-O-isopropylidene-2-keto-L-gulonate) and ancymidol (${\alpha}$-cyclopropyl-${\alpha}$-(4-methoxyphenyl)-5-pyrimidinemethanol) on the growth and flowering responses of Salvia splendens cv. Bonfire, foliar spray of dikegulac at rates of 0.06 and 0.12% and ancymidol at rates of 50 and 100 ppm, and soil drench of ancymidol at rates of 0.1 and 0.5 mg/pot were treated. Dikegulac reduced the plant height and induced the lateral shoot development by disrupting apical dominance, and thus increased the number of inflorescences and retarded flowering date. Dikegulac treatment greatly increased chlorophyll content of leaf, especially chlorophyll a. Ancymidol reduced the plant height without disrupting apical dominance and retarding flower ing date, but did not increase inflorescence number except soil drench at rate of 0.1 mg/pct. Ancymidol treatment significantly increased chlorophyll content of leaf, especially chlorophyll a. Dikegulac can be effectively used as a pinching agent and branching agent for salvia.

• Investigative Magnetic Resonance Imaging
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• v.7 no.2
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• pp.93-99
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• 2003

The different perceiving patterns of each picture, alphabetic words and Chinese characters, were widely investigated psychophysically. The more precise localisation can be done in terms of brain activity us-ing functional image technique such as PET and fMRI recently, Until now, there was no fMRI study to make direct comparison between perception of single Chinese character and simplified pictures (pictograph). We have made direct comparison of these two components using modern magnetic resonance techniques. We cannot confirm the right hemispheric dominance for perception of single Chinese character and pictographs. These two kinds of perceiving pattern can be underlying different mechanism.

• The Korean Journal of Zoology
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• v.39 no.4
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• pp.426-436
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• 1996

In previous studies, we have shown that lysosomal add phosphatase (LAP) activity increases at the dedifferentiation stage in the regenerating larval limbs of salamander, Hynobius leechii. Monoclonal antibodies against LAP were generated to determIne the spatial and temporal distribution of the protein In the regenerates.A total of 22 monoclonal antihodies recognizIng different epftopes of the protein were obtained, of which five strongly stained the regenerating limb by imunohistochemistry. in LAP immunohistochemical examination, LAP showed distribution coincident with the state of dedifferentiation, both spatially and temporally, in the limb regenerates. When unfractioned protein of regenerating salamander limbs were separated by gel electrophoresis and immunoblotted, the antibodies recognized a single protein band of 53 kl)a, which comigrates with a monomerlc subunit of IAR Using the anti-IAP antibodIes as probe, we investigated the cross-reactivities of LAPs from other sources. The immunoreadive bands on Western blots appeared to be the same In molecular mass-53 kl)a in axoloti and Xenopus, but no protein band was detected in mouse, Drosophila, or C. elegans.These results show that the antibodies generated in this study spedfically recognize Hynoblus leeclili IAp and that IAPs may be highiy conserved among amphibians. Furthermore, the distdbution of the protein is consistent with a role for LAP in the dedifferentiation process of limb regeneration.

• The Korean Journal of Zoology
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• v.39 no.4
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• pp.378-386
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• 1996

We have developed a couple of new luciferase reporter plasmida with very low background reporter actlvltlea. One can be used to measure the promoter strength, after insertion of some promoter fragment into the reporter plasmid, and the other, with very low basal promoter actlvltlea, allis In studying eukaryotic transcriptional regulators. The latter reporter plasmid contains such cli elements as a 17 nucleotide long inftlator, Spl.blndIng sftes, GAL4 binding sltea, and bInding sitea for a certain Drosophila homeodomain proteins. In an attempt to construct an improved reporter plaimid by fadlltating transcriptional termination and minimizing any interference by cryptic promoters which may be preaent in the reporter pleamld DNA, we have inserted transsrlptional termination-related signals, a three tandem repeat of SV4O polyadenylatlon signal (AAA) and the putative transcrtptional termination signal (UMS) of the mouse c-mos gene, Into just upstream of the initIator, and the promoter actlvitiea were measured by a transIent expression assay employing the Drosophila Schneider line 2 cells. As expected, the basal promoter activitIes decreased maximally when both transcription termination related elements were inserted. Moreover, the reporter plasmld with the two elements allowed more sensitive measurement of transcriptional activation than the reporter piasmid without them. Theae reporter plasmids can be used for studying transcriptional regulators of higher organisms Including mammals as well as Droiophlla melanogaiter.

• Journal of Korean Academy of Nursing
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• v.25 no.3
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• pp.538-548
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• 1995

Exercises are achievement oriented, the process is frequently perceived as hard and difficult Participants drop out from exercise programs in the middle of the training period. Dance movement, which is the deliberate and systematic use of movement, is enjoyable during the movement and provides opportunities for persons to express them-selves. Regular long term dance movement may in-duce a training effect with a decreased drop out rate. Dance movement could be one way to attain wellness, however, there have been few studies to evaluate both physiological and psychological aspects of dance movement. This study focused on evaluating the effects of dance movement training on body weight, resting blood pressure and heart rate, limb circumference and strength, stress response and subjective feelings. This quasi-experimental study was designed as a nonequivalent control group pre test -post test study. Ten healthy fe-male subjects, aged between 19 and 31 years volunteered for an eight week dance movement program. Ten healthy female subjects, between 19 and 21 years of age paticipated as controls. None of the subjects had performed regular physical activity for six months prior to the study. Dance movement was created with reference to Heber's movement guide. The Dance movement program consisted of approximately 30 minutes of dance, three days per week, for eight weeks. During each 30 minute work out, there were approximately 5 minutes of warm-up dancing, 20 minutes of conditioning dance and 5 minutes of cool-down dancing. The intensity for the conditioning phase was at between 60% and 65% of age-adjusted maximum heart rates. Body weight, resting blood pressure and heart rate, circumference of mid upper arm, mid thigh and mid calf, muscle strength of upper and lower limb, physical and psychological response to stress were measured prior to, and following the experimental treatment. Body weight was measured by digital weight scale(Kyung In Corp., Korea). Resting systolic and diastolic blood pressure were measured by sphygmomanometer, Resting heart rate was measured for one minute in a relaxed sitting position using the radial artery. Circumference of mid upper arm, mid thigh and mid calf was determined by tape measure. Muscle strength of the upper extremities was measured by a grip dynamometer (Takei Corp. No.1857, Japan) and that of the extremities was measured by the length of time the leg could be held at 45° Physical and psychological responses to stress were measured using the Symptoms of Stress (SOS)Scale. Paticipants in the dance movement were interviewed by the facilitator following the eight weeks, and their thematic responses about the dance movement were recorded. Following the eight week dance movement train-ing, body weight decreased significantly, circumference of mid thigh and mid calf increased. The length of time leg - raising could be held tended to increase following the dance movement training. Resting systolic and resting heart rate showed a tendency to decrease. Total mean score of stress response tended to de-crease, and mean score of habitual patterns, do-pression, anxiety / fear, anger and cognitive disorganization decreased remarkably following the eight week dance movement. Thematic responses about the dance movement were positive following the training.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.600-606
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• 2005

Neurofilament (NF) proteins constitute the major intermediate filament type in adult neurons. They are made up by the copolymerization of the neurofilament light (NF-L, 61 kDa), medium (NF-M, 90kDa), and heavy (NF-H, 115 kDa) proteins. Although neurofilaments play a crucial .ole in neuronal growth, organization, shape, and plasticity, their expression pattern and cellular distribution in the developing neurons remain unknown. In this study, we have produced a rabbit polyclonal antibody specific to NF-M and investigated expression of NF-M in cultured cortical neurons. Immunostaining of 12 and 24 h cultures revealed strong expression of NF-M in axonal growth cone and in the region of a soma toward the axon. Doublestaining of 4 and 14 DIV corical neurons with NF-M and PSD95 antibodies revealed that both axon and dendrites were stained intensely with NF-M antibody, and that NF-M immunostaining along dendrites is often punctate and colocalize with PSD95 puncta, indicating that the puncta represent postsynaptic spines. Presence of NF-M in the postsynaptic spine was also indicated by immunoblot analysis of the postsynaptic density fraction. Taken together, our results show intensive targeting of NF-M into axons in the early axonal development, and into spines in mature neurons, indicating its important functions in axon and spine development.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.607-612
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• 2005

Heat shock protein 70 (HSP70) is a multigene family composed of constitutively expressed members(Hsc70) and stress-inducible members (Hsp70). In the mammalian nervous system, a considerable amount of HSPs is also synthesized under normal conditions suggesting that they play an important role in the metabolism of unstressed cells. In this study we examined the expression of Hsp70 in the synapses of rat cerebellar neurons. Immunohistochemistry using specific antibodies revealed that both Hsp70 and Hsc70 are expressed in the cerebellar tissue, with strongest expression in Purkinje cells followed by granule cells. Neurons in deep cerebellar nuclei were also intensely stained by Hsp70 antibody. Immunocytochemical stainings of cultured cerebellar cells showed that Hsp70 is expressed in both Purkinje and granule cells. The expression was punctate in the soma and along dendritic trees, and the punctae were colocalized with those of PSD95, a postsynaptic marker. Immunoblotting also indicates that Hsp70 is associated with the postsynaptic density fraction. Taken together, our results indicate that the Hsp70 is expressed in cerebellar neurons in normal conditions, and that some are localized in the synapses.

• Journal of Environmental Health Sciences
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• v.6 no.1
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• pp.47-52
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• 1979

Up to the present there were the blood transfusion and the use of apparatus not to sterilize at surgical operation and medical treatments in well known infectious ways of hepatitis B virus. But all its ways were still not surely known. As the other ways of hepatitis B virus infection, it was suggested that contagion such as kissing, sexual contact, homosexuality, and varieties discharged out human body urine, stool, tear, salivary, menstrual blood, Vaginal discharge etc, and low economic status, unsanitary environmental life, alcohol and smoking related to hepatitis B virus infection. From 800 waitress who frequently contact with a lot of drinker with low economic status and unclear environmental life, this study were investigated HBs Ag (Hepatitis B surface antigen) known marker for hepatitis B virus infection in their serum, and a few conditions of their private life in order to known dangerous rate b~ing exposed to the source of hepatitis B virus infection as comparison with control group. The results were summarlized as following 1. The positive rate of HBs Ag (4.3%) was significantly higher in waitress than in control group(1.1%). 2. In waitress old, 20-24 ages group was the most as 59.5%, and positive rate of HBs Ag was trend of higher in twenties than thirties. 3. Among the waitress, one that it was less than a year were the most (62.4%) in the period to work at restaurant business, and positive rate of HBs Ag was trend of higher in propotion to period to work at there. 4. Among the waitress, one who entertained to beer hall was the most (46%), and they were trend of higher in positive rate of HBs Ag (6.3%) than other waitress. 5. Among the waitress, one to drink with smoking, and only to drink, and only to smoke, and not to drink and smoke 66.1%, 21.5%, 4.6% and 7.8%. Espically in one to drink with smoking, ther was trend of indicating the high positve rate of HBs Ag, and it was made suspicion of the relationship of alcohol smoking, contact with a lot of drinker, unclear environment to hepatitis B virus infection. In the above results, it was found that dangerous rate being exposed in hepatitis B virus infection was high in the waitress. Therefore there are required for active preventions against hepatitis B virus infection them. Also as it is possible to be infectious source in public health that waitress infected to viral hepatitis, it is thought that appropriate rules about them.