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21.
T_1 mapping成像是定量分析组织T_1值的方法,主要包括Look-Locker(LL)序列、改良的Look-Locker反转恢复序列(MOLLI)及可变多翻转角成像技术。近年来,基于Gd-EOB-DTPA的T_1 mapping成像广泛应用于肝脏。根据注射对比剂前后肝实质的T_1变化,不仅能用于对肝脏损伤程度、肝纤维化分期、肝硬化病人肝储备功能的评估,而且对肝脏局灶性病变的鉴别、肝细胞肝癌分化程度的预测也有一定的价值。就Gd-EOB-DTPA增强MRI T_1 mapping技术在肝脏疾病中的应用现状及研究进展予以综述。 相似文献
22.
Effects of chronic alcohol consumption on the broad phospholipid signal in human brain: an in vivo 31P MRS study 总被引:1,自引:0,他引:1
Estilaei MR Matson GB Payne GS Leach MO Fein G Meyerhoff DJ 《Alcoholism, clinical and experimental research》2001,25(1):89-97
BACKGROUND: Phosphorus magnetic resonance spectroscopy (31P MRS) allows for the measurement of phospholipids and their breakdown products in the human brain. Fairly mobile membrane phospholipids give rise to a broad signal that co-resonates with metabolic phosphodiesters. Chronic alcohol exposure increases the rigidity of isolated brain membranes and, thus, may affect the amount and transverse relaxation times (T2) of MRS-detectable phospholipids. We tested the hypothesis that subjects who were heavy drinkers have stiffer membranes than controls who were light drinkers, as reflected in a smaller broad signal component and a shorter T2 of the broad signal in 31P MR spectra of the brain. METHODS: Thirteen alcohol-dependent heavy drinkers (mean age 44 years) were studied by localized 31P MRS in the centrum semiovale and compared with 17 nondependent light drinkers of similar age. The broad component signal was separated from the metabolite signal by convolution difference, which is based on the large difference in line widths of these two signals. Longitudinal and T2 relaxation times were measured using standard methods. RESULTS: The broad component integral was 13% lower in the brain of heavy drinkers compared with light drinkers (p < 0.001) and remained significantly smaller after corrections for both longitudinal and transverse relaxations (p < 0.01). The T2 distribution of the broad component consistently showed two resolvable components in both groups. The fast relaxing component had the same T2 in both groups (T2 = 1.9 msec). The slower relaxing component T2 was 0.6 msec shorter in heavy drinkers compared with light drinkers (p = 0.08). CONCLUSIONS: These results, observed in the absence of white matter volume loss, are consistent with biochemical alterations and higher rigidity of white matter phospholipids associated with long-term chronic alcohol abuse. The observed smaller broad signal component in these relatively young heavy drinkers is a sensitive measure of white matter phospholipid damage. 相似文献
23.
MR T2 mapping可以通过测量组织T2值反映组织内水含量的变化,最早被应用于关节软骨和心肌病变的评估中。与传统的磁共振结构成像相比,它具有客观、精准、重复性高等优点。近年来,它在外周神经疾病中的应用越来越广泛。本文就T2 mapping的基本成像原理、在正常周围神经以及在不同种类周围神经疾病中的应用进展予以综述。 相似文献
24.
目的介绍生物束带(脱细胞异体真皮,HADM)"阶梯式倒U形"阴道紧缩术的临床效果和操作方法。方法:从本手术项目组2018年1月至2019年9月期间实施的"阶梯式倒U形"生物束带阴道紧缩术案例中,随机选择50例作为研究对象;均由同一手术项目组按照统一操作规范,采用生物束带实施"阶梯式倒U形"阴道紧缩术。统计平均手术时间;观察术前、术后(即刻)阴道口及阴道前1/3大小,计算阴道收紧有效率;测量术前、术后(即刻)会阴体高度,计算会阴体抬高有效率;检测术后2月阴道握持力,计算阴道握持力增加有效率;观察术后并发症及其发生率;随访术后2月、6月、1年患者对手术满意度。结果:50例"阶梯式倒U形"生物束带阴道紧缩术平均手术时间28min;48例术后阴道明显收紧,有效率达96%;38例会阴体高度明显抬高,有效率达76%;45例术后2月阴道握持力明显增加,有效率达90%;术后均未发生排异反应,无直肠损伤、血肿、感染等。30例得到有效随访,随访率达60%;术后2月、6月、1年患者满意度分别为88%、97%、98%。结论:"阶梯式倒U形"生物束带阴道紧缩术手术操作快捷,可有效收紧阴道、修复会阴体和增加阴道握持力等,具有临床效果确切、并发症少、安全性高、可操作性强和求美者满意度高等优势,值得临床推广应用。 相似文献
25.
目的 研究全身放松对考生的心理健康状况的影响,为考生考前提供了科学的干预措施.方法 随机抽取两组考生,其中一组为对照组(n=116),实验组(n=116)放松训练每周三次,每次20分钟,连续2个月.于训练前后采用症状自评量表(SCL-90)测试两组受试者的心理状况,并评价放松训练的作用效果.结果 对照组考生在SCL-90项目数由实验前32.0±17.7增至41.1±15.8,其中躯体化、抑郁、焦虑、敌对、偏执5项因子分值均显著性的高于实验前;放松训练实验组在实验后其SCL-90的人际关系敏感、抑郁、焦虑、敌对、恐怖5项因子分分值均低于实验前,且阳性项目分,总均分以及躯体化、人际关系敏感、抑郁等6项因子分值均显著低于对照组实验后的相应值.(P<0.05).结论 考生临近考期,应激反应明显,心身不适反应加重,心理健康水平下降;放松训练能有效改善考生考前的紧张状态,增强其心理健康水平,利于考生在考试时正常发挥. 相似文献
26.
对氧磷对血管内皮细胞的损伤作用及机制探讨 总被引:3,自引:1,他引:3
目的为探讨有机磷酸酯对血管内皮细胞和血管内皮功能是否有直接的损伤作用。方法用不同浓度的对氧磷分别与大鼠离体血管环和培养的人脐静脉单层内皮细胞共孵不同的时间,以乙酰胆碱引起的血管内皮依赖性舒张反应和单层内皮细胞通透性等为观察指标,检测对氧磷对血管内皮的损伤作用。结果对氧磷(36.3nmol/L-36.3μmol/L)与血管环共孵,呈浓度和时间依赖性地显著抑制乙酰胆碱诱导的内皮依赖性舒张反应,而对硝普钠引起的非内皮依赖性舒张反应没有明显的影响。对氧磷与内皮细胞共孵不同的时间,呈浓度和时间依赖性地显著增加单层内皮细胞的通透性。对氧磷在损伤血管内皮的同时也导致了血管组织及细胞培养液中一氧化氮浓度和超氧化物歧化酶活性的降低、脂质过氧化代谢产物丙二醛浓度的升高。加入左旋精氨酸能部分拮抗对氧磷对血管内皮功能的损伤作用,用阿托品预处理则不影响对氧磷的作用。结论该研究提示对氧磷对血管内皮细胞有直接损伤作用,其机制可能与对氧磷诱发氧化应激,进而导致脂质过氧化反应发生和增加内皮细胞的通透性有关。 相似文献
27.
目的探讨放松疗法对改善耳鸣患者睡眠质量的效果。方法采用症状自评量表(SCL-90)、阿森斯失眠量表(AIS)调查耳鸣患者共116名。将有失眠问题的46名患者随机分为实验组和对照组,实验组在接受药物治疗的同时接受放松治疗,而对照组被试仅接受药物治疗。结果①耳鸣患者AIS的平均分为(8.54±3.83),>6分共46人,失眠检出率为39.7%;②耳鸣患者的SCL-90总分及其各因子与失眠呈显著正相关(r=0.83,0.73,0.54,0.57,0.70,0.75,0.53,0.63,0.57,0.27;P<0.001);③干预后,两组被试的躯体化、抑郁、焦虑、恐怖因子及失眠得分有显著性差异(t=-2.327,P<0.021;t=-2.436,P<0.018;t=-3.094,P<0.004;t=-2.957,P<0.005)。结论放松疗法对减少耳鸣患者负性心理特征的消极影响,提高睡眠质量有显著效果。 相似文献
28.
Aim of the study
Based on screening for vasoactive traditional Chinese medicinal herbs, the present study was performed to investigate the vasoactive effects of an ethyl acetate extract from leaves of Morus alba (L.) (ELM) on rat thoracic aorta and the mechanisms underlying these effects.Materials and methods
Isolated rat thoracic rings were mounted in an organ bath system and the effects of ELM on their responses were evaluated.Results
ELM (0.125–32.000 g/l) induced a concentration-dependent relaxation (P < 0.01 vs. control) both in endothelium-intact and -denuded aortas precontracted by high K+ (6 × 10−2 M) or 10−6 M phenylephrine (PE). In endothelium-denuded aortas, ELM at the EC50 concentration reduced Ca2+-induced contraction (P < 0.01 vs. control) after PE or KCl had generated a stable contraction in Ca2+-free solution. And after incubation with verapamil, ELM induced contraction in endothelium-denuded aortas precontracted by PE (P < 0.01 vs. control); this was abolished by ruthenium red (P < 0.01 vs. ELM-treated endothelium-denuded group; P > 0.05 vs. control), but not by heparin (P > 0.01 vs. ELM-treated endothelium-denuded group; P < 0.01 vs. control).Conclusions
The results showed that ELM had dual vasoactive effects, and the relaxation was greater than the contraction. The relaxation was mediated by inhibition of voltage- and receptor-dependent Ca2+ channels in vascular smooth muscle cells, while the contraction occurred via activation of ryanodine receptors in the sarcoplasmic reticulum. 相似文献29.
This study examines the effect of yoga training program (YTP) on the severity of autism in children with High Function Autism (HFA). Twenty-nine children aged 7 to 15 (mean = 11.22, SD = 2.91) years were randomly allocated to either yoga or control group. The participants in the yoga group received an 8-week (24-session) Yoga Training Program (YTP). Parents or caregivers of participants completed autism treatment evaluation checklist (ATEC) at baseline and the end of the intervention. The results of the analysis showed that there were significant differences between the two groups with regards to all ATEC sub-scores except ATEC I (speech/language/communication). This study provides support for the implementation of a yoga training program and identifies specific procedural enhancements to reduce the severity of symptoms in children with autism. 相似文献
30.
《Journal of anxiety disorders》2013,27(4):365-378
Dental anxiety and specific phobia of dental procedures are prevalent conditions that can result in substantial distress and oral health impairment. This paper critically reviews 22 randomized treatment trials aimed at reducing dental anxiety and avoidance in adults, published in peer-reviewed journals between 1974 and 2012. The following treatment techniques are reviewed: various forms of cognitive-behavioral therapy (CBT), relaxation training, benzodiazepine premedication, music distraction, hypnotherapy, acupuncture, nitrous oxide sedation, and the use of lavender oil scent. CBT delivered in a variety of formats, including one-session treatment, has the most evidence for its efficacy. Cognitive techniques, relaxation, and techniques to increase patients’ sense of control over dental care are also efficacious but perform best when combined with repeated, graduated exposure. Other interventions require further study in randomized trials before conclusions about their efficacy are warranted. Limitations of the extant outcome research and implications for future treatment and research are discussed. 相似文献