• Korean Journal of Acupuncture
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• v.21 no.4
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• pp.101-115
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• 2004

Objective : The present studies investigated the effects of 120 Hz high frequency electroacupuncture (EA) on the stress-induced stomach dysfunction in relation to its effect on the level of stress hormones and gastric mucosal damages. The gastric mucosal injury was induced by cold-restraint stress and two acupoints corresponding to Zusanli and Sanyinjiao in man were used. Methods : Cold-restraint stress produced typical gastric lesions in all rats of the stressed groups, but the number of ulcers as well as the mean ulcer diameter were reduced by 120 Hz EA pre-treatment. Results : The degranulation value of gastric mast cell was significantly higher in cold-restrained rats than in control ones. However, with the significant reduction of degranulation values of gastric mast cells in EA pre-treated rats compared with cold-restrained rats. Cold-restarint stress induced an elevated mRNA expression of pro-inflammatory gene such as cyclooxygenases-2 and tumor necrosis factor $(TNF)-{\alpha}$, but these expression were down-regulated in EA pre-treated rats. Immunohistochemical analysis showed that while the $inhibitory-{\kappa}B{\alpha}$ and $TNF-{\alpha}$ immunorection in the surface epithelium of the stomach tended to increase, both reactions in the EA pre-treated rats showed similar pattern as observed in controls. Conclusion : These results suggest that 120 Hz EA may act as a therapeutical means for gastric mucosal damages through an activation of pituitary adrenal system. It could be concluded that 120 Hz high frequency electroaucupuncture affords a good protective potential against stress-induced gastrointestinal dysfunction.

• Journal of Welding and Joining
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• v.33 no.6
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• pp.6-12
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• 2015

Thermal fatigue life of the automobile exhaust manifold is directly affected by the restraint force according to the structure of exhaust system and bead shape of the welded joints. In the present study, the microstructural changes and precipitation behavior during thermal fatigue cycle of the 18wt% Cr ferritic stainless steel weld heat affected zone (HAZ) considering restraint stress were investigated. The simulation of weld HAZ and thermal fatigue test were carried out using a metal thermal cycle simulator under complete constraint force in the static jig. The change of the restraint stress on the weld HAZ was simulated by changing the shape of notch in the specimen considering the stress concentration factor. Thermal fatigue properties of the weld HAZ were deteriorated during cyclic heating and cooling in the temperature range of $200^{\circ}C$ to $900^{\circ}C$ due to the decrease of Nb content in solid solution and coarsening of MX type precipitates, laves phase, $M_6C$ with coarsening of grain and softening of the matrix. As the restraint stress on the specimen increased, the thermal fatigue life was decreased by dynamic precipitation and rapid coarsening of the precipitates.

• IMMUNE NETWORK
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• v.16 no.4
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• pp.242-248
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• 2016

Thymic atrophy is a complication that results from exposure to many environmental stressors, disease treatments, and microbial challenges. Such acute stress-associated thymic loss can have a dramatic impact on the host's ability to replenish the necessary naïve T cell output to reconstitute the peripheral T cell numbers and repertoire to respond to new antigenic challenges. We have previously reported that treatment with the orexigenic hormone ghrelin results in an increase in the number and proliferation of thymocytes after dexamethasone challenge, suggesting a role for ghrelin in restraint stress-induced thymic involution and cell apoptosis and its potential use as a thymostimulatory agent. In an effort to understand how ghrelin suppresses thymic T cell apoptosis, we have examined the various signaling pathways induced by receptor-specific ghrelin stimulation using a restraint stress mouse model. In this model, stress-induced apoptosis in thymocytes was effectively blocked by ghrelin. Western blot analysis demonstrated that ghrelin prevents the cleavage of pro-apoptotic proteins such as Bim, Caspase-3, and PARP. In addition, ghrelin stimulation activates the Akt and Mitogen-activated protein kinases (MAPK) signaling pathways in a time/dose-dependent manner. Moreover, we also revealed the involvement of the FoxO3a pathway in the phosphorylation of Akt and ERK1/2. Together, these findings suggest that ghrelin inhibits apoptosis by modulating the stress-induced apoptotic signal pathway in the restraint-induced thymic apoptosis.

• Herbal Formula Science
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• v.32 no.3
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• pp.263-275
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• 2024

Background : Recent studies have shown that stress fundamentally influences the functional modulation of organ and stress-related disease causes high morbidity and mortality rates. Objective : The present research investigated the effect of restraint stress on psychological and physiological responses. Results : Body weight and food intake were changed in stress group. Body weight has continuously decreased, and food intake has been slightly altered. As a result of measuring each tissue's weight, the liver and kidney's weight loss was greater than that of other organs. The lipid profile of stressed animals showed significant increases in cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels compared to control. As hepatic marker enzymes, serum glutamic pyruvic transaminase (GPT; alanine aminotransferase), glutamic oxalacetic transaminase (GOT; aspartate aminotransferase), and lactic dehydrogenase (LDH) were increased in the stress group. However, levels of serum cortisol and corticosterone did not affect. Results of the behavioral tests show that the stress group has increased activity, sluggish movements, and anxiety in the central part compared with the control group through the open field test. In the forced swim test, the stress group models had a longer duration of slowing movement, and its rate also increased. Also, in immunoblotting, stress increased the inflammatory factors Inducible Nitric Oxide Synthase (iNOS), cyclooxygenase-2 (COX-2) and activated the mitogen-activated protein kinase (MAPK) pathway. Conclusions : We observed that mouse model were affected behavioral response and liver injury when exposed to restraint stress, indicating the importance of the restraint stress in the development of psychological and physiological processes.

• Herbal Formula Science
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• v.15 no.2
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• pp.9-19
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• 2007

Nineteen Medicaments of Mutual Antagonism currently belong to pharmaceutical incompatibility and some of them cannot be used in a same prescription: if they are used in a prescription, the treatment effect is rather reduced or toxic response may be produced. Therefore. inthisstudy, it was intended to look about how Nineteen Medicaments of Mutual Antagonism were defined through survey of literatures and to review the meaning and clinical potential. According to "Sinnongbonchogyeong," "Medicaments contain the substance that suppress toxins and the toxins may be removed with use of mutual restraint or mutual detoxication substances" and they have been used in terms of this concept. Since Tang and Song era, mutual restraint and mutual inhibition were confused and were difficult to be distinguished. In terms of pharmaceutical incompatibility, the original meaning of mutual restraint was deteriorated in "Sinnongbonchogyeong". That is. mutual restraint has been used as the concept of mutual inhibition or incompatibility. When various literatures were reviewed. it could be found that Nineteen Medicaments of Mutual Antagonism were firstly included in the phrases of songs and then in "seven emotion." It could be supposed that Nineteen Medicaments of Mutual Antagonism was created based on the clinical experiences of the author and the influence of doctors. Such supposition means indicates that the interactions among medicaments could effectively be applied and mutual restraint did not belong to pharmaceutical incompatibility. However. many doctors used mutual restraint and mutual inhibition in clinical practice with no distinguishment since Song era and. especially, it is supposed that. when medicaments were used with mixing. the pharmaceutical incompatibility of "Nineteen Medicaments of Mutual Antagonism" or "Eighteen Incompatible Medicaments" were emphasized and influenced on the efficacy of pharmaceutical preparations or acted as an obstacle in treating diseases. That is. an error was transferred: mutual restraint and mutual inhibition were not distinguished and were discretionally added or deleted through common people or professionals with no specific verification. The pharmaceutical preparations that belong to Nineteen Medicaments of Mutual Antagonism belong to pharmaceutical incompatibility but. when reviewed various literatures and clinical reports. they are not thought to be the ones that can never be used. Therefore. systematic literature review and experimental research should be performed.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.5
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• pp.441-446
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• 2013

In the present study, the anti-depressant like effect of methyl gallate (MG) isolated from the stem bark of Acer barbinerve was examined in ICR mice. Body weight (BDW) and blood glucose (BDG) levels significantly decreased in the repeated restraint stress (RRS) group (2 h/day for 14 days) compared to the no stress (NS) group. To examine the effect of MG on RS-induced BDW loss and hypoglycemia, MG (10 mg/kg) and the anti-depressant fluoxetine (10 mg/kg) were administered daily for 14 days. Orally administered MG and fluoxetine significantly attenuated the RS-induced BDW loss and hypoglycemia. Interestingly, MG administered mice showed increased BDG levels in the normal and glucose feeding condition. Chronic RS-subjected mice showed immobilized and depressed behaviors. The effect of MG on the depressed behaviors was evaluated using the tail-suspension test (TST) and the forced swimming test (FST). In both tests, RS-induced immobilized behaviors were significantly reversed in MG and fluoxetine administered groups. Taken together, MG significantly attenuated the RS-induced BDW loss, hypoglycemia, and depressed behaviors. Considering that decreased BDG levels (hypoglycemia) can cause depression, MG may exert its anti-depressant like effect by preventing hypoglycemia. Our results suggest that MG isolated from A. barbinerve can exert anti-depressant like effect, and could be used as a new and natural anti-depressant therapy.

• Proceedings of the KWS Conference
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• 2001.05a
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• pp.165-167
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• 2001

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.2
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• pp.205-215
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• 1992

Load tests for fourteen small-scale foundation models combined with geotextile, sand mat and rigid mat were conducted to study the effect of geotextile(G/T), sand mat(S/M), and foundation types on deformation of foundation soils. In addition, the experimental results were compared with those obtained from numerical analysis using a software program. The main conclusions were summarized as follows: 1. The restraint effect on G/T is more outstanding on the lateral displacement than on the vertical one. 2. The single use of S/M has better effect on the restraint of vertical displacement than lateral one. 3. The use of both S/M and G/T is required for the restraint of lateral and vertical displacement. 4. Multi-layered foundation with large rigidity shows similar tendency to that of foundation reinforced with S/M and G/T.

• Structural Engineering and Mechanics
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• v.61 no.6
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• pp.711-719
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• 2017

This study investigates the effects of reinforcing bar diameter and cover depth on the shrinkage behavior of restrained ultra-high-performance fiber-reinforced concrete (UHPFRC) slabs. For this, twelve large-sized UHPFRC slabs with three different rebar diameters ($d_b=9.5$, 15.9, and 22.2 mm) and four different cover depths (h=5, 10, 20, and 30 mm) were fabricated. In addition, a large-sized UHPFRC slab without steel rebar was fabricated for evaluating degree of restraint. Test results revealed that the uses of steel rebar with a large diameter, leading to a larger reinforcement ratio, and a low cover depth are unfavorable regarding the restrained shrinkage performance of UHPFRC slabs, since a larger rebar diameter and a lower cover depth result in a higher degree of restraint. The shrinkage strain near the exposed surface was high because of water evaporation. However, below a depth of 18 mm, the shrinkage strain was seldom influenced by the cover depth; this was because of the very dense microstructure of UHPFRC. Finally, owing to their superior tensile strength, all UHPFRC slabs with steel rebars tested in this study showed no shrinkage cracks until 30 days.

• Steel and Composite Structures
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• v.1 no.1
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• pp.145-158
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• 2001

An experimental study was conducted to evaluate the effects of loading sequence and lateral bracing on the behavior of reduced beam section (RBS) steel moment frame connections. Four full-scale moment connections were cyclically tested-two with a standard loading history and the other two with a near-fault loading history. All specimens reached at least 0.03 radian of plastic rotation without brittle fracture of the beam flange groove welds. Two specimens tested with the nearfault loading protocol reached at least 0.05 radian of plastic rotation, and both experienced smaller buckling amplitudes at comparable drift levels. Energy dissipation capacities were insensitive to the types of loading protocol used. Adding a lateral bracing near the RBS region produced a higher plastic rotation; the strength degradation and buckling amplitude were reduced. A non-linear finite element analysis of a one-and-a-half-bay beam-column subassembly was also conducted to study the system restraint effect. The study showed that the axial restraint of the beam could significantly reduce the strength degradation and buckling amplitude at higher deformation levels.