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51.
52.
Most patients who survive a stroke experience some degree of physical recovery. Selecting the appropriate outcome measure
to assess physical recovery is a difficult task, given the heterogeneity of stroke etiology, symptoms, severity, and even
recovery itself. Despite these complexities, a number of strategies can facilitate the selection of functional outcome measures
in stroke clinical trial research and practice. Clinical relevance in stroke outcome measures can be optimized by incorporating
a framework of health and disability, such as the International Classification of Functioning, Disability, and Health (ICF).
The ICF provides the conceptual basis for measurement and policy formulations for disability and health assessment. All outcome
measures selected should also have sound psychometric properties. The essential psychometric properties are reliability, validity,
responsiveness, sensibility, and established minimal clinically important difference. It is also important to establish the
purpose of the measurement (discriminative, predictive, or evaluative) and to determine whether the purpose of the study is
to evaluate the efficacy or effectiveness of an intervention. In addition, when selecting outcome measures and time of assessment,
the natural history of stroke and stroke severity must be regarded. Finally, methods for acquiring data must also be considered.
We present a comprehensive overview of the issues in selecting stroke outcome measures and characterize existing measures
relative to these issues. 相似文献
53.
54.
q-Space diffusion of myelin-deficient spinal cords. 总被引:1,自引:0,他引:1
The apparent water diffusion anisotropy in white matter (WM) of excised spinal cords of myelin-deficient (md) rats and their age-matched controls was studied by high-b-value q-space diffusion MRS and MRI at different diffusion times. Non-monoexponential signal decay was observed at long diffusion times. The mean displacements in the md spinal cords were found to be higher than those of the controls. The apparent anisotropy (AA) of the fast-diffusing component was found to decrease more dramatically with the increase in diffusion time for the md spinal cords as compared with controls, whereas the AA of the slow-diffusing component in the controls was found to increase with the increase in diffusion time while that of the md cords decreased with the increase in diffusion time. When diffusion MRI was performed, similar diffusion anisotropy was extracted for the md and control spinal cords at diffusion times of 22 and 50 ms. Only at a diffusion time of about 200 ms was a significant difference obtained in the AA of the two groups. This originates from the much smaller increase in the mean displacement perpendicular to the fiber direction in the control group vs. the md group when the diffusion time was increased. 相似文献
55.
56.
OBJECTIVE: There are currently no studies that have investigated dietary supplement use in the chronic renal insufficiency (CRI) population. The objectives of this study were to determine the prevalence of dietary supplement use in a sample of adults with CRI and to examine whether the prevalence of dietary supplement use was higher in the earlier stages of CRI. DESIGN AND SETTING: Cross-sectional survey conducted at an outpatient nephrology clinic. PATIENTS: Adults (n = 100) with varying degrees of CRI. INTERVENTION: Interview-administered questionnaire. MAIN OUTCOME MEASURES: The questionnaire contained questions related to the use of dietary supplements, attitudes, and beliefs about dietary supplements, as well as medical and demographic data including gender, age, body weight, smoking status, concurrent chronic conditions, prescribed medications, serum creatinine, estimated glomerular filtration rate (GFR), etiology of CRI, income, and education level. RESULTS: The prevalence of dietary supplement use was 45%, with the most frequent use occurring in subjects with a mild to moderate degree of renal insufficiency. There were no significant differences in gender, age, body mass index, smoking status, number of concurrent chronic conditions, number of prescribed medications, income, or education level between supplement users and supplement nonusers. Further analysis of dietary supplement use showed that the number of supplements used ranged from 1 to 5 or more supplements per day, with an overall total of 36 different supplements. Dietary supplement users were significantly more concerned with their health than were supplement nonusers. The most frequent sources of supplement information were physicians and printed material; however, 75% of the dietary supplement users desired further information about their dietary supplements. CONCLUSION: This is the first study to investigate the use of dietary supplements in adults with CRI, and it provides valuable information for health care professionals regarding the dietary supplement use of their patients with CRI. 相似文献
57.
Picotamide inhibition of excess in vitro thromboxane B2 release by colorectal mucosa in inflammatory bowel disease. 总被引:1,自引:0,他引:1
Collins CE Benson MJ Burnham WR Rampton DS 《Alimentary pharmacology & therapeutics》1996,10(3):315-320
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease. 相似文献
58.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
59.
Marathon performance in relation to maximal aerobic power and training indices in female distance runners. 下载免费PDF全文
The purpose of this study was to examine the relationships of marathon performance time (MPT) to maximal aerobic power (VO2 max), physical characteristics, and training indices recorded for 12 weeks prior to a race in 35 female distance runners. The marathon experience of the subjects ranged from two to fifteen races. Physical and aerobic power characteristics (mean +/- S.D.) were: age, 35.7 +/- 8.5 yr; height, 166.4 +/- 5.7 cm; weight, 55.1 +/- 5.7 kg; body fat, 15.7 +/- 5.0%; VO2 max, 56.5 +/- 6.2 ml . kg-1 . min-1. Marathon time for this race averaged 227.0 +/- 31.6 min. Records from individual training diaries indicated the runners averaged 71.0 +/- 10.0 workout days, 10.0 +/- 10.0 two X day-1 workouts, 81.0 +/- 8.0 total workouts, 12.3 +/- 1.8 mean km . workout-1, 5402.8 +/- 1302.6 total training min, 187.0 +/- 18.0 m . min-1 training pace, 112.2 +/- 32.1 max km . wk-1, 83.1 +/- 23.4 mean km . wk-1, 998.8 +/- 282.6 km . 12 wk-1 and 13.8 +/- 2.4 mean km . day-1. MPT was positively correlated to body mass index (r = 0.52), and body fat (r = 0.52) but negatively related to VO2 max (r = -0.65). MPT was also negatively related to previous marathons completed (r = -0.47), workout days (r = -0.47), two X day-1 workouts (r = -0.52), total workouts (r = -0.56), mean km . workout-1 (r = -0.58), total training min (r = -0.56), m . min-1, training pace (r = -0.66), max km . wk-1 (r = -0.70), mean km . wk-1 (r = -0.74), km . 12 wk-1 (r = -0.74), and mean km . day-1 (r = -0.77). MPT for our population of runners may be predicted (r = 0.82, R2 = 0.68) by the following equation: MPT, (min) = 449.88 - 7.61 (-/x km.day-1 run) - 0.63 (m.min-1, training pace); SEE = +/- 18.4 min. 相似文献
60.
J Lloyd Michener Mary T Champagne Duncan Yaggy Susan D Yaggy Katrina M Krause 《Academic medicine》2005,80(1):57-61
Academic medical centers (AMCs) have traditionally provided primary care for low-income and other underserved populations. However, they have had difficulty developing lasting partnerships with other organizations serving the same populations. This article describes an exception to the rule, in which an academic division was created at Duke University Medical Center to develop effective collaborations with health care and social service providers in Durham, North Carolina, including both public agencies and private organizations. Together, the division and its partners have created and operate programs that improve health outcomes and access to care for those at risk. These programs share a number of characteristics: they are designed to meet the needs of the patient, not the provider; they are based in the community, not in the AMC; they bring services to people's homes, schools, and neighborhoods; they are multidisciplinary, combining health, social, and even mental health services; and, once established, they are revenue-generating and can be made self-supporting when grant funding ends. These programs are also innovative. They are designed to model and test new ways of organizing and delivering care. Preliminary indications suggest that they also strengthen the AMC's relationships with the surrounding community. 相似文献