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51.
Anthony Z Faranesh Dara L Kraitchman Elliot R McVeigh 《Magnetic resonance in medicine》2006,55(5):1114-1123
The purpose of this work was to investigate the use of an intravascular contrast agent to determine perfusion kinetics in skeletal muscle. A two-compartment kinetic model was used to represent the flux of contrast agent between the intravascular space and extravascular extracellular space (EES). The relationship between the image signal-to-noise ratio (SNR) and errors in estimating permeability surface area product (Ktrans), interstitial volume (ve), and plasma volume (vp) for linear and nonlinear curve-fitting methods was estimated from Monte Carlo simulations. Similar results were obtained for both methods. For an image SNR of 60, the estimated errors in these parameters were 10%, 22%, and 17%, respectively. In vivo experiments were conducted in rabbits to examine physiological differences between these parameters in the soleus (SOL) and tibialis anterior (TA) muscles in the hind limb. Values for Ktrans were significantly higher in the SOL (3.2+/-0.9 vs. 2.0+/-0.5x10(-3) min-1), as were values for vp (3.4+/-0.8 vs. 2.1+/-0.7%). Differences in ve for the two muscles (8.7+/-2.2 vs. 8.5+/-1.6%) were not found to be significant. These results demonstrate that relevant physiological metrics can be calculated in skeletal muscle using MRI with an intravascular contrast agent. 相似文献
52.
53.
不同麻醉方法对乳腺癌患者血液流变学的影响 总被引:7,自引:1,他引:6
目的比较两种麻醉方法对乳腺癌患者血液流变学的影响。方法32例ASAⅠ~Ⅱ级行择期乳腺癌根治术患者随机分为两组:Ⅰ组为全麻组;Ⅱ组为硬膜外加全麻组,诱导前硬膜外给2%利多卡因5 ml,继之行全麻诱导。全麻用药两组相同,Ⅱ组术中每50分钟硬膜外给2%利多卡因6~8 ml。术后24 h内用0.5%布比卡因镇痛,Ⅰ组术后肌注哌替啶镇痛。分别于麻醉前、麻醉后30、90 min各取桡动脉血10 ml,测血液流变学指标。结果两组麻醉后309、0 min全血高切及低切粘度、红细胞压积及红细胞聚集指数下降(P<0.05),但Ⅱ组这几项指标下降明显且持续时间长,且有血浆粘度及纤维蛋白原浓度的下降(P<0.05)。结论全麻加用硬膜外阻滞对血液流变学的影响更有利于预防术后上肢静脉血栓的形成。 相似文献
54.
东莨菪碱-曲马多-芬太尼复合液用于剖宫产术后镇痛 总被引:9,自引:1,他引:8
目的观察静脉东莨菪碱配伍曲马多与芬太尼在剖宫产术后镇痛的临床效果及不良反应。方法ASAⅠ~Ⅱ级行剖宫产术病人60例,随机分为东莨菪碱组(S组)和氟哌利多组(D组),每组30例。S组,东莨菪碱0·3mg 曲马多500mg 芬太尼0·5mg;D组,氟哌利多2·5mg 曲马多500mg 芬太尼0·5mg。均以生理盐水配置100ml药袋,静脉给予负荷剂量4ml后连接镇痛泵进行病人自控镇痛(PCA)。术后24、48h行视觉模拟评分(VAS)和镇静评分,并对用药总量、PCA量及不良反应发生情况进行观察比较。结果两组VAS差异无显著意义。D组术后24h用药总量、PCA量和镇静评分均大于术后48h,D组术后24h镇静评分比S组高(P<0·05),不良反应发生率D组明显高于S组。结论东莨菪碱配伍曲马多及芬太尼应用于剖宫产术后镇痛安全有效,不良反应发生率明显低于氟哌利多。 相似文献
55.
Gerald T Voelbel Marsha E Bates Jennifer F Buckman Gahan Pandina Robert L Hendren 《Neuropsychopharmacology》2006,60(9):942-950
BACKGROUND: Impaired neuropsychological test performance, especially on tests of executive function and attention, is often seen in children diagnosed with autism spectrum disorders (ASD). Structures involved in fronto-striatal circuitry, such as the caudate nucleus, may support these cognitive abilities. However, few studies have examined caudate volumes specifically in children with ASD, or correlated caudate volumes to cognitive ability. METHODS: Neuropsychological test scores and caudate volumes of children with ASD were compared to those of children with bipolar disorder (BD) and of typically developing (TD) children. The relationship between test performance and caudate volumes was analyzed. RESULTS: The ASD group displayed larger right and left caudate volumes, and modest executive deficits, compared to TD controls. While caudate volume inversely predicted performance on the Wisconsin Card Sorting Test in all participants, it differentially predicted performance on measures of attention across the ASD, BD and TD groups. CONCLUSIONS: Larger caudate volumes were related to impaired problem solving. On a test of attention, larger left caudate volumes predicted increased impulsivity and more omission errors in the ASD group as compared to the TD group, however smaller volume predicted poorer discriminant responding as compared to the BD group. 相似文献
56.
Hung-Yen Chin Min-Chi Chen Yu-Hung Liu Kuo-Hwa Wang 《International urogynecology journal》2006,17(6):631-635
The aim of this study was to assess the impact of delivery on the pelvic floor and whether cesarean section (C/S) can prevent pelvic floor injury. Five hundred thirty nine women were divided into three groups according to the delivery method adopted: elective C/S, emergent C/S, and vaginal delivery. A urinary incontinence questionnaire survey was conducted around 1 year postpartum. Emergent C/S may be a major risk factor for postpartum urinary incontinence and interfere with the benefit of elective C/S for preventing pelvic floor injury. Hence, not all C/S deliveries can reduce the likelihood of postpartum urinary incontinence. The key lies in whether the C/S is performed before labor. 相似文献
57.
高位硬膜外阻滞对猪急性心肌缺血/再灌注损伤时血浆TXB2和6-keto-PGF1α水平的影响 总被引:1,自引:0,他引:1
目的探讨0.5%布比卡因高位硬膜外阻滞对急性心肌缺血/再灌注损伤时血栓素B2(TXB2)和6-酮-前列腺素F1α(6-keto-PGF1α)的影响.方法健康雄性家猪20只,体重(23.0±2.5)kg,随机分为布比卡因组(Ⅰ组)、生理盐水组(Ⅱ组).静注10mg.kg-1硫喷妥钠后,气管插管,静点琥珀胆碱和芬太尼控制呼吸,维持麻醉.T3~4穿刺置入硬膜外导管,按分组分别硬膜外注射0.5%布比卡因和生理盐水各2ml,15min后结扎左冠脉前降支40min.分别在给药前和结扎40min时、开放后1h、3h、5h抽取右心房血,测定血浆TXB2、6-keto-PGF1α的浓度.给药前所测定的心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)作为基础值.结果Ⅱ组各时点血液动力学无明显变化,Ⅰ组HR、MAP和CVP分别下降22%、25%和28%.两组再灌注后1h、3h及5h TXB2、TXB2/6-keto-PGF1α比值逐渐升高,且均显著高于给药前和结扎40min.Ⅰ组升高程度显著低于Ⅱ组(P<0.05).而6-keto-PGF1α组内组间比较,变化趋势与TXB2恰相反.Ⅰ组有1只因室颤而死亡,Ⅱ组有4只(P<0.05).结论心肌缺血/再灌注损伤与TXB2和6-keto-PGF1α有一定关系,高位硬膜外阻滞通过调节缺血/再灌注后血栓素A2和前列环素的平衡在一定程度上减轻了心肌缺血/再灌注损伤. 相似文献
58.
艾灸联合弥可保治疗糖尿病周围神经病变40例 总被引:3,自引:1,他引:2
目的评价艾灸联合弥可保治疗糖尿病周围神经病变的疗效。方法对糖尿病周围神经病变患者80例按1∶1比例等分为联合组和对照组,两组基于等同的基础治疗之上,联合组用艾灸联合弥可保治疗,对照组单纯用弥可保治疗,疗程3个月,比较治疗前后的神经传导速度变化和症状改善情况。结果联合组和对照组神经传导速度均改善,以联合组改善更明显;联合组和对照组显效、有效、无效分别是52.5%、32.5%、15.0%和35.0%、27.5%、37.5%,组间差异有统计学意义(P<0.01或P<0.05)。结论建立于基础治疗之上的艾灸联合弥可保治疗糖尿病周围神经病变优于单纯弥可保治疗。 相似文献
59.
BEATA WOAKOWSKA-KAPLON GRZEGORZ OPOLSKI† 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S110-S114
Atrial fibrillation (AF) may be associated with activation of atrial natriuretic peptide (ANP). The exact trigger for the release of ANP is still being debated. Atrial volume, pressure, and wall stretch are considered to be the main determinants of ANP activation. The aim of the study was to evaluate plasma ANP concentrations in patients with persistent AF and to analyze the echocardiographic determinants of ANP concentration in this group. The study population included 67 patients, 59 ± 7 years of age, with a median AF duration of 5.5 months (range 0.1–12). The relationship between plasma ANP concentrations and echocardiographic left atrial (LA) diameter and volume, and left ventricular (LV) diameter and ejection fraction (EF) was analyzed by logistic regression analysis. The median baseline plasma ANP concentration was 63 pg/mL (range 21–126) in the study group versus 34 pg/mL (range 16–73) in a control group. The mean left antero-posterior atrial dimension, LA volume, LV enddiastolic diameter, and LVEF were 48 mm, 104 mL, 52 mm, and 54%, respectively. A significant linear positive correlation was found between plasma ANP concentration and maximal LA volume (r = 0.62, P < 0.01). A negative correlation was found between LVEF and plasma ANP concentration (r =−0.42, P = 0.01). However, by multivariate regression analysis, no echocardiographic parameter was an independent predictor of plasma ANP concentration. Plasma ANP concentrations were independent of echocardiographic measurements of LA size or LV size and function in patients with persistent AF. 相似文献
60.