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141.
This study aimed to test the efficacy of imagery and relaxation in hospitalized children's postoperative pain relief. Sixty children aged 8-12 years who had undergone appendectomy or upper/lower limb surgery and had been randomly assigned to the experimental group (n(1) = 30) listened to an imagery trip CD, whereas those in the control group (n(2) = 30) received standard care. An investigator-developed questionnaire was used, and the intensity of pain was assessed using a visual analogue scale: before (Phase 1), immediately after (Phase 2), and 1 hour after (Phase 3) intervention or standard care. The children in the experimental group reported having significantly less pain (p < .001) than the control children based on a comparison of VAS pain scores in Phases 1 and 2. There were no significant differences in nurse-assessed pain scores. The type and time of operation were related to pain intensity in children. The nurses underestimated the pain of pediatric patients. The imagery trip CD can be used to reduce children's postoperative pain in a hospital setting, although its effect is short-lasting.  相似文献   
142.
We investigated whether the signal mechanism for relaxation may be affected by inflammation of the cat esophagus. Acute esophagitis was induced by perfusion with 0.1N HCI at a rate of 1 mL/min for 45 min over three consecutive days. We then isolated esophageal smooth muscle cells by enzymatic digestion with collagenase. We pre-contracted the isolated smooth cells with acetylcholine (ACh) (10(-5) M) and compared the agonist-induced relaxation of pre-con tracted normal cells with those of esophagitic cells. Vasoactive intestinal polypeptide (VIP) caused a dose-dependent relaxation in normal cells, and this curve was down shifted in esophagitic cells. Sodium nitroprusside (SNP) or SIN-1 (NO donor) produced dose-dependent relaxation in normal cells, which was not affected by esophagitis. 8-Br-cGMP (a cGMP ana log) also induced dose-dependent relaxation to a similar extent in both normal and esoph agitic cells. Forskolin (a cAMP activator) or db-cAMP (a cAMP analog) produced dose-dependent relaxation in normal cells, and this relaxation curve was down shifted in esoph agitic cells. Western blotting was used to determine what subtype of adenylyl cyclase was involved in the cAMP pathway. Western blot analysis of homogenates derived from esophageal smooth muscle using antibodies against adenylyl cyclase types II, III, IV and V/VI revealed the presence of type V and/or type VI only. This result suggests that relaxation via a cAMP-dependent pathway rather than a cGMP dependent-pathway is down regulated in cat acute esophagitis. This subsensitivity of the cAMP related pathway may be related to the activ ity of adenylyl cyclase V/VI.  相似文献   
143.
不同粒径和浓度超顺磁性氧化铁MR信号特征的实验研究   总被引:1,自引:1,他引:0  
目的:研究超顺磁性氧化铁(superparamagnetic iron oxide,SPIO) 对周围质子的弛豫时间的影响,探讨不同颗粒、浓度SPIO的MR信号特征. 方法:对不同粒径及浓度的SPIO颗粒进行磁共振扫描,记录各个粒径和浓度的SPIO颗粒的MR T1、T2、T2~*值,评价其信号特征.结果:①不同粒径的SPIO颗粒T1值与浓度呈负相关线性关系;②当SPIO浓度较低时,随粒径减小T2和T2~*值则上升明显;当SPIO浓度较高时,随粒径减小上升渐趋缓慢;③lg(T2)与SPIO颗粒粒径和浓度之间存在线性依存关系.结论:SPIO颗粒对MR信号的影响以T1和T2效应为主;T2值可作为SPIO颗粒MR成像的主要检测指标;SPIO粒径大小、浓度和T2值三者之间存在着特定的线性关系.  相似文献   
144.

Objectives

Studies have shown beneficial effects from practicing the relaxation response (RR). Various pathways for these effects have been investigated. Previous small studies suggest that spirituality might be a pathway for the health effects of the RR. In this study, we tested the hypothesis that increased spiritual well-being by eliciting the RR is one pathway resulting in improved psychological outcomes.

Methods

This observational study included 845 outpatients who completed a 13-week mind/body Cardiac Rehabilitation Program. Patients self-reported RR practice time in a questionnaire before and after the 13-week program. Similarly, data on spiritual well-being, measured by the subscale of Spiritual Growth of the Health-Promoting Lifestyle Profile II, were collected. The psychological distress levels were measured by the Symptom Checklist-90-Revised. We tested the mediation effect of spiritual well-being using regression analyses.

Results

Significant increases in RR practice time (75 min/week, effect size/ES=1.05) and spiritual well-being scores (ES=0.71) were observed after participants completed the program (P<.0001). Patients also improved on measures of depression, anxiety, hostility and the global severity index with medium effect sizes (0.25 to 0.48, P<.0001). Greater increases in RR practice time were associated with enhanced spiritual well-being (β=.08, P=.01); and enhanced spiritual well-being was associated with improvements in psychological outcomes (β=−0.14 to −0.22, P<.0001).

Conclusion

Our data demonstrated a possible dose-response relationship among RR practice, spiritual and psychological well-being. Furthermore, the data support the hypothesis that spiritual well-being may serve as a pathway of how RR elicitation improves psychological outcomes. These findings might contribute to improved psychological care of cardiac patients.  相似文献   
145.
The counter-stress effects of relaxation on proinflammatory and anti-inflammatory cytokines were examined. From 36 medical students, 18 were randomly assigned to the relaxation group, and 18 were randomly assigned to the non-relaxation group. Relaxation lasted for four weeks. The levels of stimulated production of IL-6, TNF-α, and IL-10, and blood pressure were measured during the non-examination period (baseline period) and the pre-examination period (stress period). The levels of perceived stress were assessed by the Global Assessment of Recent Stress (GARS) scale, the Stress Response Inventory (SRI) and the Symptom Checklist-90-Revised (SCL-90-R) anxiety subscale. Repeat measure ANOVA revealed that the SRI total score, scores of the SCL-90-R anxiety subscale and diastolic blood pressure were significantly higher during the stress period than during the baseline period regardless of groups. The level of IL-6 production was significantly lower but the level of IL-10 production was significantly higher during the stress period than during the baseline period. Significant reduction in the delta (stress period value minus baseline period value) in the total GARS score, systolic and diastolic blood pressure, the levels of IL-6 and TNF-α production but significant enhancement in the delta in the level of the IL-10 production were found in the relaxation group compared with the non-relaxation group. These results suggest that relaxation is associated with reduction in stress-induced psychological or physiological responses and proinflammatory cytokine alterations but with enhancement in stress-induced anti-inflammatory cytokine alteration. Therefore, relaxation is more likely to have counter-stress effect on proinflammatory cytokines than on anti-inflammatory cytokine.  相似文献   
146.
The aim of the study was to determine pathways involved in contraction and relaxation of the mouse urinary bladder. Mouse bladder strips were set up in gassed Krebs-bicarbonate solution and responses to various drugs and electrical field stimulation were obtained. Isoprenaline (b-receptor agonist) caused a 63% inhibition of carbachol precontracted detrusor (EC50=2nM). Carbachol caused contraction (EC50=0.3μM), responses were antagonised more potently by 4-DAMP (M3-antagonist) than methoctramine (M2-antagonist). Electrical field stimulation caused contraction, which was inhibited by atropine (60%) and less by guanethidine and α,β-methylene-ATP. The neurogenic responses were not potentiated by inhibition of nitric oxide synthase. Presence of an intact urothelium significantly depressed responses to carbachol (p=0.02) and addition of indomethacin and L-NNA to remove prostaglandin and nitric oxide production respectively did not prevent the inhibitory effect of the urothelium. In conclusion, b-receptor agonists cause relaxation and muscarinic agonists cause contraction via the M3-receptor. Acetylcholine is the main neurotransmitter causing contraction while nitric oxide has a minor role. The mouse and human urothelium are similar in releasing a factor that inhibits contraction of the detrusor muscle which is unidentified but is not nitric oxide or a prostaglandin. Therefore, the mouse may be used as a model to study the lower urinary tract.  相似文献   
147.
麻黄新型仿生提取方法研究   总被引:2,自引:0,他引:2  
目的:探索麻黄的新型仿生提取方法。方法:采用液.液连续萃取法,用酸水或碱水模拟胃或肠环境,以正辛醇模拟生物膜结构,形成萃取体系提取麻黄。并对该提取技术与酸水煮提法进行麻黄碱和离体豚鼠气管的舒张率比较。结果:本仿生提取方法与酸水煮提法相比:麻黄总碱提取率提高15%以上、对豚鼠离体气管舒张率提高1.2倍以上,而浸膏得率降低约1倍。结论:该仿生提取方法提取麻黄可行。  相似文献   
148.
Our objective was to compare relaxation effects, dynamics and spatial distributions of ionic and non-ionic contrast agents in articular cartilage at concentrations typically used for direct MR arthrography at 1.5T. Dynamic MR-studies over 11h were performed in 15 bovine patella specimens. For each of the contrast agents gadopentetate dimeglumine, gadobenate dimeglumine, gadoteridol and mangafodipir trinatrium three patellae were placed in 2.5mmol/L contrast solution. Simultaneous measurements of T(1) and T(2) were performed every 30min using a high-spatial-resolution "MIX"-sequence. T(1), T(2) and DeltaR(1), DeltaR(2) profile plots across cartilage thickness were calculated to demonstrate the spatial and temporal distributions. The charge is one of the main factors which controls the amount of the contrast media diffusing into intact cartilage, but independent of the charge, the spatial distribution across cartilage thickness remains highly inhomogeneous even after 11h of diffusion. The absolute DeltaR(2)-effect in cartilage is at least as large as the DeltaR(1)-effect for all contrast agents. Maximum changes were 5-12s(-1) for DeltaR(1) and 8-15s(-1) for DeltaR(2). This study indicates that for morphologically intact cartilage only the amount of contrast agents within cartilage is determined by the charge but not the spatial distribution across cartilage thickness. In addition, DeltaR(2) can be considered for quantification of contrast agent concentrations, since it is of the same magnitude and less time consuming to measure than DeltaR(1).  相似文献   
149.
Rheumatoid arthritis (RA) is a chronic disease and has the highest rate of prevalence among rheumatic inflammatory diseases. The purpose of this study was to determine the effect of Benson Relaxation Technique (BRT) combined with medication on disease activity in patients with RA. Following ethical approval, 50 consecutive matched patients were selected and allocated into two groups, either an experimental or a control group. Patients in the experimental group received BRT combined with medication and patients in the control group were given only medication. Clinical symptoms, laboratory findings, anxiety, depression and feeling of well-being were measured before and after intervention to evaluate the effect of BRT. There was a significant difference between the two groups in anxiety, depression and feeling of well-being. Changes in clinical symptoms and laboratory findings were not large enough to be statistically significant between the two groups, but they indicated decline in disease progress. The results demonstrate that BRT can be an effective technique in reducing disease process in patients suffering from RA. However, in order to support the findings of this trial, studies with large sample size and > 8-week intervention are recommended.  相似文献   
150.
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