• Archives of Pharmacal Research
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• v.27 no.6
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• pp.646-652
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• 2004

The objective of this study was to determine the acute effect of trimetazidine (TMZ) on the pre-fatigue, fatigue and post-fatigue contractile characteristics and tension-frequency relationships of isolated rat diaphragm muscle. Muscle strips were taken from the ventral-costal aspects of the diaphragm muscle of rats killed by decapitation. The muscle strips were suspended in organ baths containing Krebs solution, with a gas mixture of 95% $O_2$ and 5% $CO_2$ at $37^{\circ}C$ and pH 7.35-7.45. After determining the thermoregulation and optimum muscle length the muscles were subjected to direct supramaximal stimulation with 0.05 Hz frequency square pulses for periods of 0.5 msec to obtain control values. After adding $5{\times}10^{-6}{\;}and{\;}5{\times}10^{-5}$ M trimetazidine solution to the respective bath media, the contractile parameters of the muscles were recorded. The contractile parameters were also recorded for both the trimetazidine and tri-metazidine-free media after application of the high frequency fatigue protocols. Later, the tension-frequency relationship was determined by applying stimulating pulses of 10, 20, 50 and 100 Hz to the muscle strips. Whilst the twitch tension obtained from the $5{\times}10^{-6}{\;}and{\;}5{\times}10^{-5}$ M trimetazidine media showed numerical increases compared to that of the controls, these were not statistically significant (p>0.05). The contraction time exhibited a dose dependent increase (p<0.001), whilst the contraction and relaxation rates did not differ significantly. The isometric contraction forces obtained with the different stimulating frequencies showed a significant increase in the tetanic contraction only at 100 Hz (p<0.05). A comparison of the pre- and post-fatigue twitch tensions in the trimetazidine media showed the post- fatigue twitch tensions to be significantly higher than those of the pre-fatigue contraction forces (p<0.05). In the $5{\times}10^{-6}{\;}and{\;}5{\times}10^{-5}$ M trimetazidine media the increases in the post-fatigue contraction force were 22 and 30%, respectively. These results demonstrated that in isolated rat diaphragm muscle, TMZ significantly limited the mechanical performance decrease during fatigue. It is our opinion that trimetazidine contributed to the observed fatigue tolerance by eliminating the factors of fatigue, due to preservation of intracellular calcium homeostasis, provision of the ATP energy levels needed by ATPase dependent pumps and especially by keeping the intracellular pH within cer-tain limits.

• Korean Journal of Psychosomatic Medicine
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• v.7 no.2
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• pp.263-273
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• 1999

Headache is a symptom with varied etiologies and extraordinarily frequent. Headaches can be a symptom of another diseases, such as meningitis, subarachnoid hemorrhage or brain tumor, may represent the disease entity itself as the case in migraine. The international Headache Society criteria were the first to distinguish between primary and secondary headache disorders. When evaluating a patient who presents with headache, the physician abviously needs to identify or exclude the myriad conditions that can cause secondary headache and initial diagnostic workup should be considered. If patient meets the criteria for a primary headache disorder, treatment commonly initiated without additional neurodiagnostic tests. The headache type, its associated feature, and the duration and the intensity of the pain attack all can influence the choice of acute therapy in migraine. Pharmacologically, such as NSAIDs, combination analgesics, vasoactive antimigraineous drugs, neuroleptics, antidepressants, or corticosteroids. Other approches to managing headache include a headache diary to identify triggers, biofeedback, relaxation technique and behavioral modification. Daily preventive medication should be considered by his attack frequency and intensity, and maintained for 4 to 6 months. Tension-type headaches are distinguished between episodic and chronic tension-type headache, but physician must make sure that patient is not drug-overuse or independent during symptomatic abortive therapy or preventive medication. The most difficult headache patients to treat are those with chronic daily headache. They often have physical dependency, low frustration tolerance, sleep problems, and depression. So discontinuation of overused medication is crucial. New developments in migraine therapy are broadening the scope of abortive and prophylactic treatment choices available to the physician. The enhanced ease of the use of sumatriptan and DHE will likely increase patient compliance and satisfaction.

• Journal of Korean Society of Steel Construction
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• v.22 no.1
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• pp.33-42
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• 2010

Patterning with a geodesic line is essential for economical or efficient usage of membrane materialsin fabric tension membrane structural engineering and analysis. The numerical algorithm to determine the geodesic line for membrane structures is generally classified into two. The first algorithm finds a non-linear shape using a fictitious geodesic element with an initial pre-stress, and the other algorithm is the geodesic line cutting or searching algorithm for arbitrarily curved 3D surface shapes. These two algorithms are still being used only for the three-node plane stress membrane element, and not for the four-node element. The lack of a numerical algorithm for geodesic lines with four-node membrane elements is the main reason for the infrequent use of the four-node membrane element in membrane structural engineering and design. In this paper, a modified numerical algorithm is proposed for the generation of a geodesic line that can be applied to three- or four-node elements at the same time. The explicit non-linear static Dynamic Relaxation Method (DRM) was applied to the non-linear geodesic shape-finding analysis by introducing the fictitiously tensioned 'strings' along the desired seams with the three- or four-node membrane element. The proposed algorithm was used for the numerical example for the non-linear geodesic shape-finding and patterning analysis to demonstrate the accuracy and efficiency, and thus, the potential, of the algorithm. The proposed geodesic shape-finding algorithm may improve the applicability of the four-node membrane element for membrane structural engineering and design analysis simultaneously in terms of the shape-finding analysis, the stress analysis, and the patterning analysis.

• Tuberculosis and Respiratory Diseases
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• v.41 no.3
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• pp.231-238
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• 1994

Backgroud: Since the demonstration of the fact that vascular relaxation by acetylcholine(Ach) results from the release of relaxing factor from the endothelium, the identity and physiology of this endothelium-derived relaxing factor(EDRF) has been the target for many researches. EDRF has been identified as nitric oxide(NO). With the recent evidences that EDRF is an important mediator of vascular tone, there have been increasing interests in defining the role of the EDRF as a potential mediator of hypoxic pulmonary vasoconstriction. But the role of EDRF in modulating the pulmonary circulation is not compeletely clarified. To investigate the endothelium-dependent pulmonary vasodilation and the role of EDRF during hypoxic pulmonary vasoconstriction, we studied the effects of $N^G$-monomethyl-L-arginine(L-NMMA) and L-arginine on the precontracted pulmonary arterial rings of the rat in normoxia and hypoxia. Mothods: The pulmonary arteries of male Sprague Dawley(300~350g) were dissected free of surrounding tissue, and cut into rings. Rings were mounted over fine rigid wires, in organ chambers filled with 20ml of Krebs solution bubbled with 95 percent oxygen and 5 percent carbon dioxide and maintained at $37^{\circ}C$. Changes in isometric tension were recorded with a force transducer(FT.03 Grass, Quincy, USA) Results: 1) Precontraction of rat pulmonry artery with intact endothelium by phenylephrine(PE, $10^{-6}M$) was relaxed completely by acetylcholine(Ach, $10^{-9}-10^{-5}M$) and sodium nitroprusside(SN, $10^{-9}-10^{-5}M$), but relaxing response by Ach in rat pulmonary artery with denuded endothelium was significantly decreased. 2) L-NMMA($10^{-4}M$) pretreatment inhibited Ach($10^{-9}-10^{-5}M$)-induced relaxation, but L-NMMA ($10^{-4}M$) had no effect on relaxation induced by SN($10^{-9}-10^{-5}M$). 3) Pretreatment of the L-arginine($10^{-4}M$) significantly reversed the inhibition of the Ach ($10^{-9}-10^{-5}M$)-induced relaxation caused by L-NMMA($10^{-4}M$) 4) Pulmonary arterial contraction by PE($10^{-6}M$) was stronger in hypoxia than normoxia but relaxing response by Ach($10^{-9}-10^{-5}M$) was decreased, 5) With pretreatment of L-arginine($10^{-4}M$), pulmonary arterial relaxation by Ach($10^{-9}-10^{-5}M$) in hypoxia was reversed to the level of relaxation in normoxia. Conclusion: It is concluded that rat pulmonary arterial relaxation by Ach is dependent on the intact endothelium and is largely mediated by NO. Acute hypoxic pulmonary vasoconstriction is related to the suppression on NO formation in the vascular endothelium.

• Journal of Oriental Neuropsychiatry
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• v.24 no.3
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• pp.257-262
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• 2013

Objectives : Aripiprazole is unique drug among the SGA (Second generation antipsychotics) in its pharmacology and pharmacokinetics,but is similar in clinical efficacy. Aripiprazole acts as a partial agonist at dopamine D2 receptors, activating the receptor but eliciting a reduced response compared to the natural neurotransmitter. There are some side effects of aripiprazole, the most common side effects of aripiprazole are headache, nausea, vomiting, insomnia, tremor, constipation and EPS. Difficulty in opening eyes is not defined EPS yet, but it is a rare but important side-effect symptom of aripiprazole. Methods : This article is about a case of side-effect symptom of aripiprazole, 26-year-old single female suffering from schizophrenia had difficulty in opening eyes while she was taking antipsychotics. During the hospitalization, the relaxation therapy is helpful not only to reduce tension in the eyelids but also to headache. Results : It is important that early recognition of aripiprazole-induced oculogyric dystonia can prevent life-threatening complications. Education medical staff to this easily treatable reaction will improve overall quality of health care. Conclusions : This case notifies the need for awareness of the risk of acute oculogyric dystonia in adolescent female patients receiving aripiprazole.

• The Korean Journal of Physiology
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• v.24 no.1
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• pp.77-90
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• 1990

There have been conflicting reports concerning the effect of Panax ginseng on the contractility of vascular smooth muscle, i.e., Panax ginseng extract has been reported to cause relaxation, contraction or to have no effect on the tension of vascular smooth muscle. A further investigation of $Ca^{++}$ stores which supply $Ca^{++}$ for contraction of vascular smooth muscle is needed to understand the underlying mechanisms of this conflicting effect of ginseng alcohol extract (GAE). The present study was intended to examine the sources of calcium mobilized for contraction of vascular smooth muscle by GAE. Aortic ring preparations were made from the rabbit thoracic aorta and endothelial cells were removed from the ring. The contractility of the aortic ring was measured under various experimental conditions and $Ca^{++}$ flux across the membrane of aortic ring and the sarcoplasmic reticulum and mitochondria were measured with a calcium selective electrode. The result were summarized as follows; 1) At low concentration of extracellular $Ca^{++}$, GAE increased the contractility of vascular smooth muscle in dose-dependent fashion except high concentration $Ca^{++}$ (1 mM). 2) In the presence of ryanodine, GAE still increased contractility of vascular smooth muscle as much as control group, but in the presence of caffeine, GAE increased it significantly. i.e. Their effects seemed to be additive. 3) In the presence of verapamil+lanthanum, and verapamil+lanthanum+ryanodine, the contractility of the vascular smooth muscle was decreased, but a dose dependent increase in vascular tension was still demonstrated by GAE although total tension was low. 4) GAE increased $Ca^{++}$ efflux from vascular smooth muscle cells, but have no effect on $Ca^{++}$ influx. 5) GAE increased $Ca^{++}$ efflux from sarcoplasmic reticulum and mitochondria vesicles. From the above results, it may be concluded that GAE increased the release of $Ca^{++}$ from sarcoplasmic reticulum, mitochondria or other intracellular $Ca^{++}$ stores of vascular smooth muscle, but it does not increase $Ca^{++}$ influx across the plasma membrane.

• Proceedings of the Korean Society of Computer Information Conference
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• 2009.01a
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• pp.169-172
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• 2009

본 논문은 SOM을 이용하여 비행슈팅게임을 하는 게이머의 긴장과 이완상태를 학습한다. 학습된 SOM을 이용해 게이머의 새로운 심박데이터가 입력되었을 때 긴장과 이완 상태에서 플레이하는 게이머의 인식을 제안한다. 게이머들은 비행슈팅게임을 플레이하면서 게임 환경들의 패턴들에 익숙해진다. 게이머들은 반복하면서 지루해지면서 자연스럽게 긴장감도 떨어지게 된다. 만약 긴장이완 정도를 알 수 있다면 게이머의 상태에 맞게 게임환경을 조절하여 긴장감을 유지할 수 있을 것이다. 본 연구에서는 비행슈팅게임을 하는 게이머의 심박신호를 이용하여 게이머의 긴장이완상태를 신경망 SOM으로 분류한다. SOM은 주어진 입력패턴에 정확한 답을 정해주지 않고 자기 스스로 학습하여 해답을 찾는 신경망중의 하나이다. 따라서 게이머의 심박신호는 SOM 학습을 통해 게이머의 긴장과 이완상태들을 군집화 할 수 있다. 비행슈팅게임을 20회 반복 플레이하여 SOM으로 게이머의 심박신호를 입력해 본 결과 긴장이완상태를 인식 할 수 있었다.

• The Korean Journal of Pharmacology
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• v.26 no.1
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• pp.13-23
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• 1990

Methylene Blue (MeB) and gentian violet $(10^{-6}{\sim}10^{-4}\;M)$ produced contractions in isolated thoracic aortic preparations of rabbits in a dose-dependent fashion, while other dyes, evans blue and eosine yellowish, did not affect the basal tension in the same range of doses. Porcine mesenteric arterial rings also responded to MeB with dose-dependent contractions. Single dose of $10^{-4}$ M MeB produced a biphasic response: contraction followed by relaxation. The contraction developed slowly within $2{\sim}4$ min and peaked in about 20 minutes and then slowly relaxed to the basal level. Tyramine $(10^{-4}\;M)$ also induced contraction but it developed faster and was more persistent than that of MeB. While the tyramine-induced tension was reproducible, the MeB-induced one wat not reiterable until 3 to 5 hours after washing out the MeB. Adding $10^{-4}$ M MeB further potentiated the contraction induced by $10^{-4}$ M tyramine. However, the MeB contraction was not affected by further addition or tyramine. Both tyramine- and MeB-induced tensions were abolished or significantly inhibited by pretreatment with various drugs acting on the sympathetic nervous system. The tyramine-induced tension was more sensitive to guanethidine and 6-hydroxydopamine than the MeB-induced tension, while the latter was more sensitive to $Ca^{2+}-free$ PSS and reserpine. But they have similar sensitivity to prazosin. The MeB-induced tension was significantly inhibited but not abolished by 6-hydroxydopamine pretreatment. However, either tyramine or 6-hydroxydopamine could not affect the basal tension of the ring that MeB once had been tested. These results suggest that MeB-induced contractions of rabbit thoracic aorta and porcine mesenteric artery result from a release of endogenous norepinephrine from adrenergic nerve endings and are dependent in part on extracellular calcium, and that the potency of MeB to release or to deplete norepinephrine is greater than that of either tyramine or 6-hydroxydopamine.

• Journal of East-West Nursing Research
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• v.7 no.1
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• pp.68-81
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• 2002

The purpose of this study is to analyze the type of ego states and stress coping style on female college students who are in the course of nursing study. This study is performed in the view of Transactional Analysis and designed to scrutinize descriptive correlations between the type of ego states and stress coping style. The subject is consists of 144 freshmen and sophomore, 138 junior and senior students group, who are students of K nursing college located in Seoul. The sampling investigation period is on Sept. 14, 2002 to Oct. 26, 2002. The measuring instrument used for Transactional Analysis ego state is 50 items Ego-gram research paper devised by Dusay(1997). For studying coping style, Folkman & Lazarus's measurement(1984) was adopted, which is translated and modified by Han, and Oh,(1990). Health states is adopted by standardized health inspecting instrumental table (Cornell Medical Index:CMI) which is designed for Korean people by Ko and Park(1980) Statistic average and standard deviation were generated by using SPSS PC+, t=test and Pearson correlation. The results were as follows: 1) In the type of ego states on both groups indicated the arithmetic apex NP(maximum value), then the point A was high and the data made a down slope to point AC. In the comparison to type of ego states between two groups, only at point CP, the data value of upper year students represented higher than that of lower year ones by c(t=2.28, p=.023). 2) Stress coping style of whole students were highly and affirmatively dedicated to research. Especially hopeful aspect(t=.67, p=.05), relaxation of tension(t=-2.16, p=.03) made significant difference each other in the view of arithmetic calculation. 3) In view of nursing students' physical health states, there is significant difference in past history(t=2.50, p=.013) and in case of mental health states, there are considerable discrepancies between lower group(73.52) and upper group(75.11)(p<.05). In view of all field, state of tension(t=2.13, p=.048) has difference. 4) While verifying coping style in terms of ego states level between lower and upper students group, In type CP, high level ego states group indicated significant difference on stress coping style area than low leveled group and made such sequences as the central point of problem, In type NP, sequences such as the central point of problem, In type A, the central point of problem, In type FC, hopeful aspect and In type AC, hopeful aspect and indifference were derived significantly different (p<.05). 5) While verifying health state differences in the level of lower and upper ego states, In type FC, low level group(150.29) marked higher point than upper group(145.19), there is remarkable discrepancy and so did whole health state(p=.014), In type AC both mental state(p=.000) and whole health state (p=.015) showed differences. 6) When analyzing correlations between whole students' ego states, copying style and health state, all type of ego state showed differences(p<.001). In correlations between ego state and health state, in type FC physical state had an apex and there are inverse correlations among the other types. Especially, type FC showed inverse correlations with great discrepancies(p<.05). In mental state, type NP(${\gamma}=.198$, p<.001) and type A(${\gamma}=.166$, p<.05) represented straight correlations with remarkable differences. Especially, In type AC showed inverse correlations(${\gamma}=.282$, p<.001). In case of correlations between copying style and health state, indifference(${\gamma}=-.157$) and relaxation of tension(${\gamma}=-.158$) presented great difference(p<.05). In mental state, central point of problem and search for social support showed straight correlations with great discrepancies(p<.05), hopeful aspect and indifference showed inverse correlations with considerable differences(p<.001).

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.3
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• pp.21-29
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• 2023

In this study, the stress characteristics of temporary fixed steel rods were analyzed in the "temporary fixing system using internal prestressing tension", which is mainly applied to the construction of superstructures by FCM. It was difficult to confirm the changes in initial tensile force in this system because the steel rod was internally connected to the pier and the PSC BOX. Therefore, measurement was performed before and after the completion of each segment using an FBG sensor to measure the change in the micro length of the steel rod. The results of the analysis showed that 75% to 90% of the maximum vertical contraction of the steel rod that occurred until the completion of the cantilever segment occurred in the fixing ~ 1segment, and the maximum loss of initial prestressing force was 39%. Such excessive loss of tension force to 1 segment means that tension is needed to improve the precision of construction during the fixation, and re-tension is needed to secure stability for conduction of cantilever segments after the completion of 1segment. In the 2 ~ last segment, the stress of the steel rod decreased gradually, and in the summer, the decrease in stress tended to partially recover due to the increase in the length of the steel rod corresponding to the increase in the vertical volume of PSC BOX. The dominant factor in the stress change in 2~ last segment in this phenomenon is judged to be the change in the length of the steel rod according to the temperature. Unlike the change in length, the relaxation was 1.2-2.7%, which was mostly offset by the opposite stress corresponding to the temperature stress. Therefore, a plan was proposed to improve the internal stress, such as adjusting the fixation time.