• The Korean Journal of Physiology and Pharmacology
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• 제1권3호
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• pp.303-313
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• 1997

The role of the lower esophageal sphincter(LES) is characterized by the ability to maintain tone and to relax allowing the passage of a bolus. It is known that LES relaxation during swallowing may be induced by the cessation of the tonic neural excitation and the activation of non-adrenergic, non-cholinergic(NANC) inhibitory neurons. Furthermore, it is generally accepted that the relaxation of the smooth muscle is mediated primarily by the elaboration of adenosine 3',5'-cyclic monophosphate(cyclic AMP) and guanosine 3',5'-cyclic mono-phosphate(cyclic GMP) via activation of adenylate cyclase and guanylate cyclase, respectively. It is thus possible that cyclic nucleotides might be a second messenger involved in neural stimulation-induced relaxation of LES, although a relationship between relaxation and changes in cyclic nucleotides after neural stimulation has not been established. The present study was performed to define the participation of cyclic nucleotides in the relaxation of LES of dog in response to neural stimulation. Electrical field stimulation(EFS) caused relaxation of the canine isolated LES strips in a frequency-dependent manner, which was eliminated by pretreatment with tetrodotoxin$(1{\mu}M)$, but not by atropine$(100{\mu}M)$, guanethidine$(100{\mu}M)$ and indomethacin$(10{\mu}M)$. The nitric oxide synthase inhibitors, $N^G-nitro-L-arginine$, $N^G-nitro-L-arginine$ methyl ester and $N^G-monomethyl-L-arginine$ inhibited EFS-induced relaxation. Additions of sodium nitroprusside, a nitrovasodilator and forskolin, a direct adenylate cyclase stimulant, caused a dose-dependent relaxation of LES smooth muscle. Effects of sodium nitroprusside and forskolin were selectively blocked by the corresponding inhibitors, methylene blue for guanylate cyclase and N-ethylmaleimide(NEM) for adenylate cyclase, respectively. Dibutyryl cyclic AMP and dibutyryl cyclic GMP caused a concentration-dependent relaxation of the LES smooth muscle tone, which was not blocked by NEM or methylene blue, respectively. However, both NEM and methylene blue caused significant antagonism of the relaxation in LES tone in response to EFS. EFS increased the tissue cyclic GMP content by 124%, whereas it did not affect the tissue level of cyclic AMP. Based on these results, it is suggested that one of the components of canine LES smooth muscle relaxation in response to neural stimulation is mediated by an increase of cyclic GMP via the activation of guanylate cyclase. Additionally, an activation of cyclic AMP generation system was, in part, involved in the EFS-induced relaxation.

• Macromolecular Research
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• 제17권10호
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• pp.785-790
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• 2009

In this paper, the relaxation behavior of the regenerated silk fibroin (SF) films was investigated using dielectric thermal analysis (DETA), and compared with the dynamic mechanical behavior obtained from dynamic mechanical thermal analysis (DMTA), in order to gain a better understanding of the characteristics of dielectric behavior of SF film and identify the differences between the two analyses. Compared to DMTA, DETA exhibited a higher sensitivity on the molecular relaxation behaviors at low temperature ranges that showed a high $\gamma$-relaxation peak intensity without noise. However, it was not effective to examine the relaxation behaviors at high temperatures such as $\alpha-$ and ${\alpha}_c$-relaxations that showed a shoulder peak shape. On the contrary, DMTA provided more information regarding the relaxation behaviors at high temperatures, by exhibiting the changes in width, intensity and temperature shift of the $\alpha$-relaxation peak according to various crystallinities. Conclusively, DETA and DMTA can be utilized in a complementary manner to study the relaxation behavior of SF over a wide temperature range, due to the different sensitivity of each technique at different temperatures.

• 대한간호학회지
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• 제30권2호
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• pp.282-292
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• 2000

A meta-analysis of 14 quasi-experimental studies was conducted to compare the effect of size on various relaxation therapies applied to patients and health volunteer students. These studies were selected from theses, dissertations and papers that have been done between 1982 to 1993. Also They have a randomized or nonequivalent control group in a pre test-post test design. The studies were evaluated in different ways; 1) types of relaxation therapy, 2) total amount of time of relaxation therapy, and 3) types of outcome variables. For a group of homogenious studies, the weighted mean effect size and standard error were estimated. Some findings are summarized as follows : 1. Jacobson relaxation therapy had a larger effect on systolic and diastolic blood pressures than on state anxiety. 2. For the total time of relaxation therapy, (longer than 60 minutes) had a much larger effect in decreasing systolic and diastolic blood pressures than in the case of a time period shorter than 60 minutes. 3. Relaxation therapy applied to surgery patients also had a larger effect in decreasing state anxiety than when applied to other patients.

• 폴리머
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• 제37권2호
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• pp.135-140
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• 2013

Poly(methyl acrylate)-poly(acrylonitrile) 공중합체의 응력완화 실험은 용매기를 부착한 인장 시험기를 사용하여 여러 온도의 공기 중, 증류수, pH 3, 7, 11 용액에서 실행하였다. Ree-Eyring and Maxwell 모델로부터 얻은 완화스펙트럼 식에 실험적인 응력완화 곡선을 대입하여 poly(methyl acrylate)-poly(acrylonitrile) 공중합체의 완화스펙트럼을 얻었다. 완화스펙트럼의 계산은 Laplace 변환법을 사용한 컴퓨터 프로그램을 이용하였다. 이들 시료의 완화스펙트럼은 유동단위의 분자량과 자체확산 분포와 밀접한 관계가 있음을 알 수 있었다.

• 근관절건강학회지
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• 제17권2호
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• pp.132-141
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• 2010

Purpose: This study was to examine the effect of Progressive Muscle Relaxation Therapy on stress and anxiety of traffic accident patients. Method: Subjects of this study were 39 hospitalized patients at orthopedic ward. An experimental group received Progressive Muscle Relaxation Therapy five times each week for four weeks beginning from the fourth day following the injury, whereas a control group received regular care. A tape of Jacobson's Progressive Muscle Relaxation Therapy recorded in Korean by the Rheumatoid Health Academic Society was used for relaxation therapy. Data were analyzed using SPSS 13.0 for Windows. Results: Patients who received Progressive Muscle Relaxation Therapy experienced lower level of stress (t=-9.829, p<.001) and anxiety (t=-15.303, p<.001) than those who did not. Conclusion: Progressive Muscle Relaxation Therapy may be an effective nursing intervention to reduce levels of stress and anxiety of traffic accident patients.

• Elastomers and Composites
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• 제45권4호
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• pp.250-255
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• 2010

비뉴톤 점탄성 Maxwell 요소와 탄성 스프링으로 이루어진 3 요소 비뉴톤 모델로부터 응력완화 식을 유도하였다. 이 식을 응력완화 실험 결과에 적용하여 여러 가지 모델 파라메타를 계산하였다. 모델 파라메타로부터 계산한 이론 곡선은 실험적인 응력완화 곡선과 잘 일치하였다. 비선형 점탄성 모델 파라메타로부터 섬유고분자 물질의 홀부피, 미세구조, 점탄성성질, 역학적인 성질 등을 연구하였다. 응력완화 실험은 용매기를 부착한 인장 시험기를 사용하였으며, 시료는 두 종류의 polyacrylonitrile-polyvinylchloride 공중합체와 또 다른 두 종류의 PVC 모노 필라멘트 섬유를 여러 온도의 공기와 물속에서 응력완화 실험을 하였다.

• 대한정형도수물리치료학회지
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• 제24권2호
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• pp.75-81
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• 2018

Background: The purpose of this study was to investigate the effect of various relaxation techniques on various dysfunction problems caused by shortening of the sagittal muscles. Method: The subjects were 44(18 males, 26 females). The subjects were composed of 3 groups. The experimental group consisted of 14 patients with proprioceptive neuromuscular facilitation stretching (PNF) technique, control group A 15 patients with self myofacial release (SMR) ball exercise, and control group B with 15 patients with Sling exercise. After 3 weeks of relaxation on the hamstring muscle, the length of the hamstring muscle before and after the intervention was compared. Results: The results of relaxation exercise of the snake muscles applied to passive PNF group, SMR ball group, and Sling relaxation group are as follows. 1. In the passive PNF group, the muscle length of the hamstring muscle was significantly increased after the intervention. 2. The muscle length of the hamstring muscle was significantly increased after the intervention in the SMR ball group. 3. Sling relaxation group significantly increased the muscle length of the hamstring muscle after sling exercise intervention. 4. Passive PNF group showed the greatest change in muscle length before and after intervention than SMR ball group and Sling relaxation group. Conclusion: Passive PNF relaxation therapy, SMR ball relaxation therapy, and Sling relaxation therapy applied to the hamstring muscle were effective in increasing muscle length of the hamstring muscle. PNF relaxation therapy showed the most significant effect after 3 weeks intervention.

• 한국식품조리과학회지
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• 제1권1호
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• pp.53-56
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• 1985

6%, 8%, 10%의 도토리묵에 데여 응력완화검사 (stress relaxation test)를 실시하여 전형적인 응력완화곡선 (stress relaxation curve)을 구하였다. 연속잔차법 (successive residual method)을 사용하여 완화곡선을 분석한 결과, 도토리묵은 spring 하나에 Maxwell 모형이 세개인 7-element, generalized Maxwell model 로 해석할 수 있었다. 또한 도토리묵가루의 농도가 커질수록 도토리묵의 평형탄성율(E$_{e}$) 과 탄성율( $E_1$, $E_2$, $E_3$)이 증가하였다.

• 한방재활의학과학회지
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• 제18권1호
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• pp.125-140
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• 2008

Objectives : The purpose of this study was to investigate the effect of Progressive Muscle Relaxation(PMR) on stress and muscle relaxation in healthy people. Methods : Sample group of 14 healthy subjects had been treated by progressive muscle relaxation for 10 days. Control group of 14 healthy subjects were not treated during the same period. Outcomes were assessed by Meridian-Electromyograph(MEMG), Heart Rate Variability(HRV), Stress Reaction Inventory(SRI). Results : The contraction and fatigue of erector spinae muscle by MEMG had decreased significantly in Sample group. There was no significant difference between two groups in the HRV and SRI. Conclusions : Further studies analysing PMR effect on stress and muscle relaxation are needed.

• 한국자기공명학회논문지
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• 제14권1호
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• pp.9-17
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• 2010

The water proton relaxation rates increase linearly with concentrations of contrast agents, and could be expressed as a function of the concentrations. In this paper, we have investigated MR properties of two different contrast agents, $GdCl_3$ and $CoCl_2$. Relaxivity coefficients were calculated from individual contrast agent solutions, and used for predicting relaxation rates at mixtures of two contrast agents. From the experimental results, we have discussed the feasibility of constructing water solutions with the desired relaxation times using specific mixtures of contrast agents.