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91.
BACKGROUND: The natural course of longitudinal changes in peritoneal permeability and membrane area has been studied mostly by performing single-dwell studies in selected patients during treatment with peritoneal dialysis. PURPOSE: To evaluate the permeability characteristics of the peritoneal membrane by measuring drained ultrafiltration volume relative to initial glucose concentration in dialysis fluid from the start to the end of continuous ambulatory peritoneal dialysis (CAPD) treatment in a selected cohort of patients with and without peritonitis. DESIGN: A retrospective analysis of a group of patients whose peritoneal function was prospectively followed by recording drained ultrafiltration volume and glucose concentration in dialysis fluid for each dwell time, every day, during the time in CAPD treatment. Mean values from a 1-month period starting after the first 3 weeks of CAPD treatment were compared with the mean values from the last month of treatment. Approximately 11 500 exchanges were analyzed. Evaluations were done separately for short (day) and long (night) dwell times. PATIENTS AND STATISTICS: Of 132 patients commencing CAPD treatment in the time period selected for inclusion, 51 had enough data to be included in this study. Of these, 29 patients experienced one or more episodes of successfully treated peritonitis. The selection of patients was not based upon patient characteristics, but upon criteria to satisfy predefined demands, such as number of measurements in each period, time since an episode of peritonitis, and time on CAPD treatment. Data were analyzed in three different groups: patients with episodes of peritonitis, patients without peritonitis, and both groups together. To assess changes between monthly mean at the start and at the end of CAPD, paired t-test was performed. Patients were also stratified into two groups according to low and high glucose in dialysis fluid at the start of CAPD (cutoff = 2 g/dL). Additionally, we used linear regression analyses to predict the level of drained ultrafiltration volume for a given level and change in glucose concentration. Mean treatment time for the entire group was 20 months (median 14.3 months), ranging from 6 to 69 months. RESULTS: No statistical differences in glucose concentrations were found between the periods compared. In the entire group there was an increase in ultrafiltration volume from the start to the end of CAPD treatment, for both day (p = 0.009) and night (p = 0.013) exchanges. Also, for patients without peritonitis, an increase appeared for day (p = 0.046) and night exchanges (p = 0.053). However, for the cohort with peritonitis, only an insignificant increase was indicated. Patient characteristics, diabetic patients, the need for glucose in dialysis fluid when commencing CAPD treatment, the number of episodes of peritonitis, and time on CAPD did not influence the change in ultrafiltration. Regression analyses showed higher ultrafiltration response to a given level and change in glucose concentration at the end of CAPD treatment compared to the start values, also for the cohort with peritonitis. The regression coefficient between these variables was also significantly changed for both day (p < 0.0001) and night (p = 0.027) exchanges. CONCLUSION: A significant change in the regression coefficient between glucose in dialysis fluid and ultrafiltration volume reflects an increase in ultrafiltration response to a given level and change in glucose concentration during time on CAPD treatment. A parallel change after 5- and 9-hour dwells can be explained by a decrease in peritoneal surface area combined with a lesser decrease in peritoneal conductivity. However, changes in Starling forces across the peritoneal membrane are possible even in the absence of changes in peritoneal membrane characteristics.  相似文献   
92.
目的:应用超声骨密度/骨质量测量仪对东莞地区中老年非暴力性骨折患者进行检测,探讨各参数的变化规律及临床意义,并确立骨折的骨密度阈值。方法:①实验对象:选择2003-09/2006-08在东莞石龙人民医院进行超声骨密度测定的非暴力性骨折东莞地区中老年患者107例,男30例,女77例;同期同龄进行超声骨密度测定的无骨折求诊者392例,作为对照组,男83例,女309例。②实验分组:根据年龄分为3个时期:46~60岁为老年前期、61~75岁为老年期、76岁以上为高龄期,以及相应男女组及骨折与非骨折组。③实验方法:采用法国DMS公司UBIS5000型超声骨密度/骨质量测量仪对中老年非暴力性骨折者、无骨折就诊者进行超声骨密度测量。④实验评估:比较两组男女及不同年龄段超声振幅衰减平均值、超声传播速度、骨硬度指数、T值(代表患者测量值如超声振幅衰减平均值和20岁正常人的测量值之间的差异)、Z值(代表患者测量值如超声振幅衰减平均值和同龄正常人的测量值之间的差异)。结果:两组499例患者全部进入结果分析。①总体比较:男、女性骨折组与非骨折组比较,除超声传播速度差别无统计学意义外(P>0.05),其余指标(超声振幅衰减、骨硬度指数、T值、Z值)非骨折组高于骨折组(P<0.01)。②分年龄组比较:老年前期组与总体一致,老年组、高龄组主要指标无统计学意义。应用方差分析对女性骨折组各年龄组之间进行比较,除骨硬度指数外(P<0.05),其余指标差异无显著性;男性骨折组各年龄组之间比较得出与女性一样结果。③男性与女性骨折组比较:除T值男性组高于女性组外(P<0.01),其余指标(超声振幅衰减、超声传播速度、骨硬度指数、Z值)差异均无统计学意义。结论:①中老年人群骨质下降至一定程度(相应测量参数为骨折阈值)时容易发生脆性骨折。②致脆性骨折的骨质量条件与性别、年龄因素无明显相关性。③东莞地区步入老年期后不论男女骨质疏松现象相当普遍,是否会出现骨折关键在于有否外力作用,对其预防性诊断很有价值。  相似文献   
93.
目的:设计一种护理床,以预防缺乏自控能力的老年人和智障人员发生坠床危险。方法:利用重心测定原理,计算患者在床上的位置,并辅以红外探测报警,实现自动报警防坠床的主要功能。结果:该护理床在Labview环境下编制监控程序,建立自动监控报警系统;以相应比例的砝码代替患者进行实验测试。结论:测试结果表明:①该装置监控到报警响应时间短,能够及时发现隐患,减少患者意外发生。②护理床采用全自动监控报警,可减轻护理人员的负担。  相似文献   
94.

Background

CMR is considered the ‘gold standard’ for non-invasive LV and RV mass quantitation. This information is solely based on gradient-recalled echo (GRE) sequences while contrast dependent on intrinsic T1/T2 characteristics potentially offers superior image contrast between blood and myocardium. This study aims, for the first time in humans, to validate the SSFP approach using explanted hearts obtained from heart transplant recipients. Our objective is establish the correlation between and to validate steady-state free precession (SSFP) derived LV and RV mass vs. autopsy mass of hearts from cardiac transplants patients.

Methods

Over three-years, 58 explanted cardiomyopathy hearts were obtained immediately upon orthotopic heart transplantation from the OR. They were quickly cleaned, prepared and suspended in a saline-filled container and scanned ex vivo via SSFP-SA slices to define LV/RV mass. Using an automatic thresholding program, segmentation was achieved in combination with manual trimming (ATMT) of extraneous tissue incorporating 3D cardiac modeling performed by independent and blinded readers. The explanted hearts were then dissected with the ventricles surgically separated at the interventricular septum. Weights of the total heart not excluding papillary and trabecular myocardium, LV and RV were measured via high-fidelity scale. Linear regression and Bland-Altman plots were used to analyze the data. The intra-class correlation coefficient was used to assess intra-observer reliability.

Results

Of the total of 58 explanted hearts, 3 (6%) were excluded due to poor image quality leaving 55 patients (94%) for the final analysis. Significant positive correlations were found between total 3D CMR mass (450 ± 111 g) and total pathology mass (445 ± 116 g; r = 0.99, p < 0.001) as well as 3D CMR measured LV mass (301 ± 93 g) and the pathology measured LV mass (313 ± 96 g; r = 0.95, p < 0.001). Strong positive correlations were demonstrated between the 3D CMR measured RV mass (149 ± 46 g) and the pathology measured RV mass (128 ± 40 g; r = 0.76, p < 0.001). The mean bias between 3D-CMR and pathology measures for total mass, LV mass and RV mass were: 3.0 g, -16 g and 19 g, respectively.

Conclusions

SSFP-CMR accurately determines total myocardial, LV and RV mass as compared to pathology weighed explanted hearts despite variable surgical removal of instrumentation (left and right ventricular assist devices, AICD and often apical core removals). Thus, this becomes the first-ever human CMR confirmation for SSFP now validating the distinction of ‘gold standard’.  相似文献   
95.
96.

Background  

In patients with severe aortic stenosis (AS), long-term data tracking surgically induced effects of afterload reduction on reverse LV remodeling are not available. Echocardiographic data is available short term, but in limited fashion beyond one year. Cardiovascular MRI (CMR) offers the ability to serially track changes in LV metrics with small numbers due to its inherent high spatial resolution and low variability.  相似文献   
97.
目的:观察经皮经腔冠状动脉内移植外周血干细胞治疗急性心肌梗死的可行性与近期临床疗效。方法:①实验对象:选取2003-11/2005-01辽宁省人民医院收治的急性心肌梗死患者70例,男56例,女14例,年龄(60±10)岁,体质量(73±11)kg,急性心肌梗死病程(5±2)d,均对本实验知情同意,实验方案经辽宁省人民医院伦理委员会批准。70例患者随机数字表法分为细胞移植组、常规治疗组,35例/组。两组基线资料基本相似。②实验方法:常规治疗组单纯给予药物治疗 冠状动脉造影术或支架植入术。细胞移植组在常规治疗的基础上应用粒细胞集落刺激因子皮下注射动员自体骨髓干细胞,连续5d,第6天经血细胞分离机分离采集外周血干细胞悬液57mL,经over the wire球囊导管中心腔注入梗死相关动脉,注入CD34细胞数量为(7.25±7.33)×107个。③实验评估:在外周血干细胞动员、采集及经冠状动脉回输过程中观察患者不良反应。于术前及术后6个月检查两组患者左室形态、心功能、室壁节段性运动积分的改变。结果:术后6个月,细胞移植组全部完成随访,常规治疗组23例完成随访。①手术前后超声心动图参数值的变化:与术前比较,术后6个月细胞移植组左室收缩末容积、室壁节段性运动积分指数均明显下降(P<0.05),左室射血分数显著升高(P<0.05)。术后6个月与常规治疗组比较,细胞移植组左室射血分数明显升高,室壁节段性运动积分指数显著降低,差异有显著性意义(P<0.05)。②安全性评估:外周血干细胞动员时不良反应占37.1%,分离和采集过程不良反应占15.3%,经冠状动脉内回输过程不良反应占20.0%。结论:经皮经腔冠状动脉移植自体外周血干细胞治疗急性心肌梗死,可在近期有效地减少心肌梗死缺血面积,减轻左室重构,改善心功能。  相似文献   
98.
The effect of the maternal use of benzodiazepines (BZD) on the fetus and the newborn infant has been studied in a representative series of 17 newborn infants (BZD group). The pregnancy and the perinatal period were characterized by 20 items. On the 2nd day of life, a neurologic investigation was performed and comprised a total of 38 items, subgrouped into items of reflexes/reactions, tonus, and other symptoms and signs. An optimum finding for each item was selected. The results were compared with a group of 21 newborns fetally exposed to psychotropic drugs other than BZD (drug group) and a reference group of 29 newborns with no known fetal exposure to drugs. Infants in the BZD group had a lower birth weight for birth length, as compared to both the drug group and the reference group. Significant differences in frequency of pre- and perinatal complications and in neuro-behavior between the BZD group and the reference group were found in all groups of items. We conclude that the use of BZD during pregnancy is associated with impaired intrauterine growth and an increased frequency of pre- and perinatal events. It affects the newborn infant neurologically mainly in the form of intoxication and withdrawal symptoms.  相似文献   
99.
Growth and neurodevelopment at 6, 10 and 18 months of age have been studied prospectively and longitudinally in a series of 17 children born to mothers who used benzodiazepines (BZD) in therapeutic doses as their only psychotropic drug throughout pregnancy. The results were compared with a group of 29 children born to mothers without any known use of psychotropic drugs. The BZD-exposed children caught up their low mean birth-weight, at an early stage, whereas the slightly decreased head circumference at birth remained at the same low level. In five infants, a pattern of craniofacial anomalies was found. Deviating neurodevelopmental and clinical symptoms and signs were common. The gross motor development was retarded at 6 and 10 months, but was nearly normal at 18 months. Impaired fine motor functions were found on all follow-up occasions. At 18 months, the most prominent finding was a delayed development of pincer grasp. The BZD-exposed children showed deviations in muscle tone and pattern of movements more frequently than children in the reference group. The study suggests that the use of BZD in therapeutic doses throughout pregnancy can have negative effects on the development of children up to 18 months of age. The long-term hazards cannot be evaluated from these results. A further follow-up at early school age is needed and is in progress.  相似文献   
100.
The 5-lipoxygenase metabolites of arachidonic (AA) and eicosapentaenoic acid (EPA), 5S,12R-dihydroxy-6,8,10,14-eicosatetraenoic acid (LTB4), 5-hydroxyeicosatetraenoic acid (5-HETE), 5S,12R-dihydroxy-6,8,10,14,17-eicosapentaenoic acid (LTB5), and 5-hydroxyeicosapentaenoic acid (5-HEPE), were injected intradermally into the ear skin of steers to assess their in vivo potency as chemotactic factors for bovine neutrophils. A dose of 30 picomoles of LTB4 was required to elicit a significant extravascular dermal accumulation of neutrophils (P less than 0.05). In contrast, 1.0 nanomole of LTB5 was required to achieve a cellular influx equivalent to that elicited by 30 picomoles of LTB4. Nearly five times as many neutrophils were present in the bovine dermis injected with 1.0 nanomole of LTB4 compared with sites given the equivalent dose of LTB5 (245 cells/sq mm vs. 52 cells/sq mm). Six nanomoles of either 5-HETE or 5-HEPE were required before a significant neutrophil accumulation occurred. These results show clearly that 5-lipoxygenase metabolites can initiate the extravascular accumulation of bovine neutrophils in vivo. However, the chemotactic potency of the EPA metabolites is much reduced when compared with that of the homologous AA lipids. The results obtained support the premise that modification of the inflammatory response, including control of cellular influxes, by dietary supplementation with EPA is feasible.  相似文献   
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