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51.
Towards quantitative measurements of relaxation times and other parameters in the brain 总被引:1,自引:0,他引:1
Summary The nature and physical significance of the relaxation times T1 and T2 and of proton density are described. Methods of measuring T1 and T2 are discussed with emphasis on the establishment of precision and the maintenance of accuracy. Reported standards of success are briefly reviewed. We expect sensitivities of the order of 1% to be achievable in serial studies. Although early hopes of disease diagnosis by tissue characterisation were not realised, strict scientific method and careful calibration have made it practicable to apply relaxation time measurement to research into disease process. Serial measurements in patients and correlation with similar studies in animal models, biopsy results and autopsy material taken together have provided new knowledge about cerebral oedema, water compartmentation, alcoholism and the natural history of multiple sclerosis. There are prospects of using measurement to monitor treatment in other diseases with diffuse brain abnormalities invisible on the usual images. Secondarily derived parameters and notably the quantification of blood-brain barrier defect after injection of Gadolinium-DTPA also offer prospects of valuable data. 相似文献
52.
放松训练辅助聆听音乐对介入治疗的颅内动脉瘤患者睡眠质量影响的效果评价 总被引:1,自引:0,他引:1
目的 评价放松训练配合聆听音乐对颅内动脉瘤患者介入治疗前后睡眠质量的影响,以期提高患者的睡眠质量.方法 收集符合纳入标准的55例颅内动脉瘤患者,随机分为观察组28例和对照组27例,对照组患者按照颅内动脉瘤常规护理进行护理,观察组在常规护理的基础上让患者坚持放松训练配合聆听音乐,以匹兹堡睡眠质量指数作为评定工具评价2组患者睡眠质量情况,自制问卷评价患者主观感受.结果 放松训练配合聆听音乐改善了患者的睡眠质量,2组比较,差异有统计学意义(P<0.01).结论 放松训练配合聆听音乐可提高介入治疗的颅内动脉瘤患者睡眠质量. 相似文献
53.
Sofia Kvernby Marcel Jan Bertus Warntjes Henrik Haraldsson Carl-Johan Carlh?ll Jan Engvall Tino Ebbers 《Journal of cardiovascular magnetic resonance》2014,16(1)
Background
Quantification of the longitudinal- and transverse relaxation time in the myocardium has shown to provide important information in cardiac diagnostics. Methods for cardiac relaxation time mapping generally demand a long breath hold to measure either T1 or T2 in a single 2D slice. In this paper we present and evaluate a novel method for 3D interleaved T1 and T2 mapping of the whole left ventricular myocardium within a single breath hold of 15 heartbeats.Methods
The 3D-QALAS (3D-quantification using an interleaved Look-Locker acquisition sequence with T2 preparation pulse) is based on a 3D spoiled Turbo Field Echo sequence using inversion recovery with interleaved T2 preparation. Quantification of both T1 and T2 in a volume of 13 slices with a resolution of 2.0x2.0x6.0 mm is obtained from five measurements by using simulations of the longitudinal magnetizations Mz. This acquisition scheme is repeated three times to sample k-space. The method was evaluated both in-vitro (validated against Inversion Recovery and Multi Echo) and in-vivo (validated against MOLLI and Dual Echo).Results
In-vitro, a strong relation was found between 3D-QALAS and Inversion Recovery (R = 0.998; N = 10; p < 0.01) and between 3D-QALAS and Multi Echo (R = 0.996; N = 10; p < 0.01). The 3D-QALAS method showed no dependence on e.g. heart rate in the interval of 40–120 bpm. In healthy myocardium, the mean T1 value was 1083 ± 43 ms (mean ± SD) for 3D-QALAS and 1089 ± 54 ms for MOLLI, while the mean T2 value was 50.4 ± 3.6 ms 3D-QALAS and 50.3 ± 3.5 ms for Dual Echo. No significant difference in in-vivo relaxation times was found between 3D-QALAS and MOLLI (N = 10; p = 0.65) respectively 3D-QALAS and Dual Echo (N = 10; p = 0.925) for the ten healthy volunteers.Conclusions
The 3D-QALAS method has demonstrated good accuracy and intra-scan variability both in-vitro and in-vivo. It allows rapid acquisition and provides quantitative information of both T1 and T2 relaxation times in the same scan with full coverage of the left ventricle, enabling clinical application in a broader spectrum of cardiac disorders. 相似文献54.
放松训练联合音乐疗法在局麻手术病人中的应用研究 总被引:1,自引:0,他引:1
目的 探讨放松训练联合音乐疗法对局麻手术患者术中、术后的心理、疼痛敏感度及血流动力学的影响。方法 将120例患者按手术安排顺序单双数分为实验组与对照组,每组各60例。对照组患者给予局麻常规护理,实验组在常规护理的基础上对患者进行放松训练联合音乐疗法,观察两组患者术前和术后的疼痛敏感度和焦虑程度的变化及术前一日、入室前、术中、术后心率、血压的变化。结果 组间比较,实验组患者术后焦虑值(SAS)和疼痛视觉模拟量表(VAS)评分明显低于对照组患者,术中、术后30min的收缩压、舒张压、心率均低于对照组(P〈0.01),实验组术前一日、入室前的收缩压、舒张压、心率与对照组比较,差异无统计学意义(P〉0.05);组内比较,两组患者入室前的收缩压、舒张压、心率均高于术前一日(P〈0.01),实验组术中、术后30min的收缩压、舒张压、心率低于入室前(P〈0.01),而与术前一日比较差异无统计学意义(P〉0.05);对照组术中、术后30min的收缩压、舒张压、心率与入室前比较,差异无统计学意义(P〉0.05)。结论 放松训练联合音乐疗法,可以减轻患者的焦虑情绪及降低疼痛敏感度,并有利于维持局麻手术患者术中、术后生命体征的稳定。 相似文献
55.
《Clinical gastroenterology and hepatology》2022,20(3):e398-e406
ObjectiveHigh-resolution manometry (HRM) is the current standard for characterization of esophageal body and esophagogastric junction (EGJ) function. We aimed to examine the prevalence of abnormal esophageal motor patterns in health, and to determine optimal thresholds for software metrics across HRM systems.DesignManometry studies from asymptomatic adults were solicited from motility centers worldwide, and were manually analyzed using integrated relaxation pressure (IRP), distal latency (DL), and distal contractile integral (DCI) in standardized fashion. Normative thresholds were assessed using fifth and/or 95th percentile values. Chicago Classification v3.0 criteria were applied to determine motor patterns across HRM systems, study positions (upright vs supine), ages, and genders.ResultsOf 469 unique HRM studies (median age 28.0, range 18–79 years). 74.6% had a normal HRM pattern; none had achalasia. Ineffective esophageal motility (IEM) was the most frequent motor pattern identified (15.1% overall), followed by EGJ outflow obstruction (5.3%). Proportions with IEM were lower using stringent criteria (10.0%), especially in supine studies (7.1%–8.5%). Other motor patterns were rare (0.2%–4.1% overall) and did not vary by age or gender. DL thresholds were close to current norms across HRM systems, while IRP thresholds varied by HRM system and study position. Both fifth and 95th percentile DCI values were lower than current thresholds, both in upright and supine positions.ConclusionsMotor abnormalities are infrequent in healthy individuals and consist mainly of IEM, proportions of which are lower when using stringent criteria in the supine position. Thresholds for HRM metrics vary by HRM system and study position. 相似文献
56.
Phospholamban is required for CaMKII-dependent recovery of Ca transients and SR Ca reuptake during acidosis in cardiac myocytes 总被引:1,自引:0,他引:1
Initially during acidosis, Ca transient amplitude (Delta[Ca]i) and the rate constant of [Ca]i decline (k(Ca)) are decreased, but later during acidosis Delta[Ca]i and k(Ca) partially recover. This recovery in rat myocytes could be inhibited by KN-93 suggesting that CaMKII-dependent protein phosphorylation (and enhanced SR Ca uptake) may be responsible. To test whether phospholamban (PLB) is required for the Delta[Ca]i and k(Ca) recovery during acidosis, we used isolated myocytes from PLB knockout (PLB-KO) vs. wild-type (WT) mice. [Ca]i was measured using fluo-3. During the initial phase of acidosis (1-4 min), Delta[Ca]i decreased in WT myocytes (n = 8) from 1.75 +/- 0.19 to 1.10 +/- 0.13 DeltaF/F0 (P < 0.05) and k(Ca) decreased from 3.20 +/- 0.22 to 2.38 +/- 0.18 s(-1) (P < 0.05). Later during acidosis (6-12 min), Delta[Ca]i partially recovered to 1.41 +/- 0.18 DeltaF/F0 and k(Ca) to 2.78 +/- 0.22 s(-1) (i.e. both recovered by approximately 50%). CaMKII inhibition using KN-93 completely prevented this recovery of Delta[Ca]i and k(Ca) during late acidosis in WT myocytes. In PLB-KO myocytes (n = 11) Delta[Ca]i decreased during early acidosis from 2.92 +/- 0.31 to 1.33 +/- 0.17 DeltaF/F0 (P < 0.05) and k(Ca) decreased from 10.45 +/- 0.56 to 7.58 +/- 0.68 s(-1) (P < 0.05). However, Delta[Ca]i did not recover during late acidosis and k(Ca) decreased even more (6.59 +/- 0.65 s(-1)). Parallel results were seen for contractile parameters. We conclude that PLB is crucial to the recovery of Delta[Ca]i and k(Ca) during acidosis. Moreover, PLB phosphorylation by CaMKII plays an important role in limiting the decline in Ca transients (and contraction) during acidosis. 相似文献
57.
目的:总结标准外伤大骨瓣开颅及颅硬脑膜修补方法对重型颅脑损伤治疗的体会。方法:回顾总结54例采用标准外伤大骨瓣开颅术并常规行硬脑膜减张严密缝合(人工硬脑膜补片或自体颞肌筋膜)治疗重型颅脑损伤的过程。结果:术后并发症有颅内再出血、脑嵌顿(骨窗疝)、脑穿通畸形、脑积水、癫痫。无脑脊液漏及感染,无皮下积液。死亡15例,植物生存4例,重残5例,中残8例,良好22例。结论:重型颅脑损伤手术中用人工脑膜补片(主要牛心包膜)或自体颞肌筋膜减张缝合硬脑膜可以明显减少术后并发症的发生,为愈后提供良好的帮助。 相似文献
58.
目的观察替米沙坦对自然衰老模型大鼠脑血管内皮功能的改善作用及PPARγ与PPARβ阻断剂对上述作用的影响。方法选取12只雄性衰老SD大鼠(24月龄),分衰老组(6只)和衰老-替米沙坦组(6只)(5mg/kg/d,灌胃给药,1月),并以6月龄SD大鼠(6只)作为对照组。观察替米沙坦对大鼠血压、心率、脑血管功能的影响。分离大鼠脑基底动脉进行体外培养,以PPARβ的阻断剂GSK0660(1μM,24h)、PPARγ的阻断剂GW9662(1μM,24h)为工具药物,分析上述药物对替米沙坦(10μM,24h)介导的衰老大鼠模型脑血管内皮功能改善作用的影响。结果 24月龄衰老大鼠的血压、心率与6月龄大鼠比较,差异无统计学意义。与对照组大鼠比较,衰老模型大鼠乙酰胆碱诱导的脑血管内皮依赖性舒张功能显著下降,而硝酸甘油诱导的非内皮依赖性舒张功能未见明显改变。在培养血管组织中,替米沙坦孵育可显著改善衰老大鼠模型脑基底动脉的血管内皮依赖性舒张功能,PPARγ的阻断剂GW9662可显著阻断替米沙坦的作用,但PPARβ的阻断剂GSK0660对替米沙坦的作用则无显著影响。结论替米沙坦介导的脑血管内皮功能的改善作用依赖于PPARγ。 相似文献
59.
Masoume Rambod Farkhondeh Sharif Nasrin Pourali-Mohammadi Nilofar Pasyar Forough Rafii 《International journal of nursing studies》2014
Background
Haemodialysis patients may suffer from pain and impairment of quality of life. Some complementary interventions, such as relaxation therapy, might affect the pain and quality of life. The present study aimed to identify the effectiveness of Benson's relaxation technique in relieving pain and improving the quality of life in haemodialysis patients.Study design
The study was a randomized controlled trial.Setting and participants
The data were collected in two haemodialysis units affiliated to Shiraz University of Medical Sciences. A total of 86 haemodialysis patients were randomly assigned to either the intervention (receiving Benson's relaxation technique) or the control group (routine care) from 2011 to 2012.Intervention
The patients in the intervention groups listened to the audiotape of relaxation technique twice a day each time for 20 min for eight weeks.Measurements and outcomes
The pain numeric rating scale and Ferrans and Powers Quality of Life Index-dialysis version questionnaire were completed at baseline and 8 weeks after the intervention. The data were analyzed using independent t-test and ANCOVA.Results
The results of ANCOVA showed a significant difference between the intervention and the control group concerning the mean score of the intensity of pain (F = 6.03, p = 0.01). Moreover, a significant difference was found between the intervention and the control group regarding the total quality of life (F = 10.20, p = 0.002) and health-functioning (F = 8.64, p = 0.004), socioeconomic (F = 12.45, p = 0.001), and family (F = 8.52, p = 0.005) subscales of quality of life.Conclusion
These findings indicated that Benson's relaxation technique might relieve the intensity of pain and improve the quality of life in haemodialysis patients. Thus, Benson's relaxation technique could be used as part of the care practice for relieving the pain intensity and improvement of the quality of life in haemodialysis patients. 相似文献60.