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91.
For convenience, small volumes of platelet concentrate (PC) intended for neonatal patients are often dispensed in syringes. The PC, however, may remain in the syringe for up to several hours before the actual transfusion. As there are few data on the effect of such syringe storage on PCs, the in vitro syringe storage properties of small volumes of 1- and 5-day-old units, and volume-reduced units of PC were evaluated. In four separate experiments, PCs were stored in syringes in volumes of 10, 15, or 30 mL for up to 6 hours at 20 to 24 degrees C without agitation. Platelets were evaluated for pH, platelet count, and a variety of biochemical and in vitro functional assays. Results showed that even with the equivalent of a full unit of platelets stored in the syringe for up to 6 hours, the pH did not fall below 6.0. Although there was an increase in lactate production and consumption of glucose, which paralleled the decline in pH, the changes were not greater than those seen in platelets stored up to 5 days in gas-permeable blood bags. Similar results were seen for PCs stored in syringes for 6 hours at 37 degrees C. All of the pH levels recorded at the end of 6 hours of syringe storage were above the minimum required level of pH 6.0. Data from in vitro platelet assays imply that at any time during their shelf life, PCs can be stored in gas-impermeable polypropylene syringes for up to 6 hours and can maintain acceptable storage characteristics; in vivo data are needed to confirm these observations.  相似文献   
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To evaluate the effect of SMN2 copy number on disease severity in spinal muscular atrophy (SMA), we stratified 45 adult SMA patients based on SMN2 copy number (3 vs. 4 copies). Patients with 3 copies had an earlier age of onset and lower spinal muscular atrophy functional rating scale (SMAFRS) scores and were more likely to be non‐ambulatory. There was, however, no difference between the groups in quantitative muscle strength or pulmonary function testing. Functional scale may be a more discriminating outcome measure for SMA clinical trials. Muscle Nerve, 2009  相似文献   
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Kinematic changes in Parkinson's disease (PD) gait are well documented; however, upper body dynamics are less understood. Harmonic ratios (HRs) measure the rhythm of trunk accelerations and can be examined in the vertical, anterior‐posterior, and mediolateral planes, providing an indication of global walking stability (lower HR indicates poorer stability). We examined differences in HRs between persons with PD and healthy older adults and relationships between HRs and stride parameters. Eleven people with PD and 11 older adults walked over ground at their preferred pace. A triaxial accelerometer measured trunk accelerations. HRs and spatiotemporal parameters were calculated and standardized to remove the influence of gait velocity. The PD group exhibited lower HRs in all three planes, with the most pronounced differences in the mediolateral and anterior‐posterior planes. Greater stride time variability was most closely associated with a lower anterior‐posterior HR in PD and the presence of disease with the mediolateral HR. By demonstrating decreased walking stability in medial‐lateral and anterior‐posterior planes, we conclude that HRs offer unique information beyond that of typical stride parameters, and stride time variability is most closely associated with these direct measures of global walking stability. © 2008 Movement Disorder Society  相似文献   
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The aim of this experiment is to understand how Parkinson's disease (PD) medication affects the autonomic responses of individuals during an acute exercise stress test. Fourteen people with PD and fifteen healthy individuals age‐matched between 50 and 80 years performed a modified Bruce protocol. Subjects with PD performed the test once off medication (PD‐off) and then 1 week later on medication (PD‐on). Heart rate (HR), blood pressure (BP), VO2, and norepinephrine (NE) levels were taken at rest and at peak exercise. At peak exercise HR, BP, and NE values for the PD‐on and PD‐off group were all significantly lower than healthy controls, regardless of whether subjects were on their medication. Autonomic abnormalities during exercise in this population appear to be disease manifested and not impactedby medications used to treat PD. We can assume, both on and off medication, this population will show markedly lower BP, HR, and NE responses. © 2009 Movement Disorder Society  相似文献   
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Background contextChronic back pain is a condition characterized by high rates of disability, health-care service use, and costs.PurposeThe purpose of this study was to identify factors associated with patients' satisfaction with their last health-care provider visit for chronic low back pain (LBP).Study design/settingA cross-sectional, state-level, telephone survey was administered to patients with chronic LBP.Patient sampleThe sample consisted of 624 individuals with chronic LBP who reported seeing a health-care provider in the previous year.Outcome measuresDependent variables included satisfaction with last visit for LBP and intent to seek care from additional providers. Independent variables included the Roland-Morris Disability Questionnaire, 3-month pain ratings using a 0 to 10 Likert scale, the Medical Outcomes Survey Short Form 12, and self-reported health service utilization (provider type, number of visits to health-care providers, medication use during the previous month, and treatments and diagnostic tests during the previous year).MethodsBivariate and multivariate analyses were used to explore how demographic, insurance-related, and health-related characteristics were associated with patient satisfaction.ResultsParticipants who were not satisfied with one or more aspects of their last clinic visit were younger (51.0 vs. 54.21 years), reported higher 3-month pain ratings (7.23 vs. 6.53), and were more commonly Hispanic (53.2% vs. 46.8% for other ethnicities) and uninsured (43.1% vs. 29.3% for other insurance groups). Those who intended to seek care from additional providers were younger (50.05 vs. 55.49 years), had higher 3-month pain ratings (7.20 vs. 6.46), had lower Short Form 12 mental health component scores (44.75 vs. 49.55) and physical component scores (30.07 vs. 31.55), and were more commonly black (54.6% vs. 45.4% for other racial groups) and uninsured (56.9% vs. 43.1% for other insurance groups). Narcotic use was associated with satisfaction (odds ratio=2.12, p=.01), whereas lack of insurance was associated with respondents' intent to seek care from additional providers (odds ratio=2.97, p<.01).ConclusionsFactors other than disability were associated with satisfaction with chronic LBP visits. Understanding the role of medication in satisfaction and its implications for the health behaviors of this highly disabled population may be particularly important.  相似文献   
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The objective of this project was to develop computer-adaptive tests (CATs) using parent reports of physical function in children and adolescents with cerebral palsy (CP). The specific aims of this study were to (1) examine the psychometric properties of an item bank of lower-extremity and mobility skills for children with CP; (2) evaluate a CAT using this item bank; (3) examine the concurrent validity of the CAT with the Pediatric Outcomes Data Collection Instrument (PODCI) and the Functional Assessment Questionnaire (FAQ); and (4) establish the discriminant validity of simulated CATs with Gross Motor Function Classification System (GMFCS) levels and CP type (diplegia, hemiplegia, or quadriplegia). Parents ( n =190) of children and adolescents with spastic diplegic (48%), hemiplegic (22%), or quadriplegic (30%) CP consisting of 108 males and 82 females with a mean age of 10 years 7 months (SD 4y 1mo, range 2–21y) and in GMFCS levels I to V participated in item pool calibration and completed the PODCI and FAQ. Confirmatory factor analyses supported a unidimensional model for the 45 basic lower-extremity and mobility items. Simulated CATs of 5, 10, and 15 items demonstrated excellent accuracy (intraclass correlation coefficients [ICCs] >0.91) with the full item bank and had high correlations with PODCI transfers and mobility (ICC = 0.86) and FAQ scores (ICC = 0.77). All CATs discriminated among GMFCS levels and CP type. The lower-extremity and mobility skills item bank and simulated CATs demonstrated excellent performance over a wide span of ages and severity levels.  相似文献   
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The present review was conducted to determine the efficacy of high-voltage monophasic pulsed current (HVMPC) in treating diabetic ulcers, assess its effect on skin lesions with each of the pathophysiologic factors potentially contributing to diabetic ulcers, evaluate its safety, and identify treatment parameters. Electronic search of PubMed, Scopus, PEDro and Google Scholar databases was conducted. The revised tool for assessing risk of bias in randomised trials (RoB 2), the risk of bias in non-randomised studies-of interventions (ROBINS-I) and the Joanna Briggs Institute (JBI) critical appraisal tool were used to assess risk of bias and methodological quality. Overall quality of evidence was determined using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) principles. Thirty-two studies matched the eligibility criteria, and included 1061 patients with 1103 skin lesions of selected aetiologies; 12 randomised controlled trials were included in quantitative synthesis. HVMPC plus standard wound care (SWC) likely increased the probability of complete wound healing of pressure ulcers (PrUs) compared with sham/no stimulation plus SWC; relative risk (RR) 2.08; 95% CI: [1.42, 3.04], p = 0.0002; I2 = 0%, p = 0.61; eight studies, 358 ulcers. Although conclusive evidence regarding the effect of HVMPC on diabetic ulcers was not found, collateral evidence might suggest a potential benefit. Direct evidence, with moderate certainty, may support its efficacy in treating PrUs, albeit few adverse reactions were reported. Other observations, moreover, might indicate that this efficacy may not be limited to PrUs. Nonetheless, several aspects remain to be clarified for safe and effective application of electrical stimulation for wound healing.  相似文献   
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