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991.
992.
OBJECTIVES: To describe the development of the Amputee Mobility Predictor (AMP) instrument designed to measure ambulatory potential of lower-limb amputees with (AMPPRO) and without (AMPnoPRO) the use of a prosthesis, and to test its reliability and validity. DESIGN: Measurement study using known groups method and concurrence with existing measures. SETTING: Academic medical center. PARTICIPANTS: A convenience sample of 191 lower-limb amputee subjects who had completed prosthetic training, 24 in the reliability study (mean age +/- standard deviation, 68.3+/-17.9y, range, 28-99y) and 167 in the validity study (mean age, 54.8+/-18.6y; range, 18-100y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Intra- and interrater reliability; construct validity by known groups method; concurrent validity by comparisons with 6-minute walk test, Comorbidity Index, age, and time since amputation; predictive validity by comparison with 6-minute walk test after controlling for other factors. RESULTS: Interrater reliability was.99 for subjects tested with and without their prosthesis; intrarater reliability was.96 and.97. Both the AMPnoPRO (P<.0001) and the AMPPRO scores (P<.0001) distinguished among the 4 Medicare functional classification levels. The AMP correlated strongly with 6-minute walk scores (AMPnoPRO r=.69, P<.0001; AMPPRO r=.82, P<.0001) and the amputee activity survey (AMPnoPRO r=.67, P<.0001; AMPPRO r=.77, P<.0001), and negatively correlated with age (AMPnoPRO r=-.69, P<.0001; AMPPRO r=.56, P<.0001) and comorbidity (AMPnoPRO r=-.43, P<.0001; AMPPRO r=.38, P<.0001). CONCLUSION: The AMP with and without a prosthesis are reliable and valid measures for the assessment of functional ambulation in lower-limb amputee subjects.  相似文献   
993.
Manipulation of the cervical spine is one of the few potentially life-threatening procedures performed by physiotherapists. Is it worth the risk? A comparison of risks versus benefits indicates that at present, the risks of cervical manipulation outweigh the benefits: manipulation has yet to be shown to be more effective for neck pain and headache than other interventions such as mobilisation, whereas the risks, although infrequent, are serious. This analysis is of particular concern because the conditions for which manipulation is indicated are benign and usually self-limiting. Because physiotherapists have legal and ethical obligations to the community to avoid foreseeable harm and provide optimum care, it may be prudent to determine who in our profession should perform cervical manipulation. That is, the profession could restrict the practice of cervical spine manipulation. Although all registered physiotherapists in Australia are entitled to perform cervical manipulation, few choose to use this intervention. Therefore, it might be feasible to encourage those practitioners who wish to use cervical manipulation to undertake formal education programs. Such a requirement could be embodied in a code of practice that discourages those without formal training from performing cervical manipulation. By taking such measures, we could ensure that our profession exercises wisdom in its monitoring and use of cervical manipulation.  相似文献   
994.
PURPOSE: Parkinson's disease (PD) is a chronic progressive neurological disorder that frequently results in nearly total disability. This study examined changes over 3 years in patients' experiences living with PD, and explored how participants' health perceptions and predicted mortality at baseline related to their actual death by Year 3. DESIGN AND METHODS: Data were obtained from a local sample of 109 participants by in-home interviews. RESULTS: The collected results (1) suggested a disconnection between the participants' responses to open-ended questions about the disorder, compared with their responses to questions structured by the investigators; (2) demonstrated changes in responses to structured and open-ended questions; and (3) demonstrated that respondents who declined to predict whether they would be living in 10 years were three times more likely to die by Year 3 than those who answered the question. IMPLICATIONS: Results demonstrate the importance of identifying the most important issues for the individual with PD and suggest that these issues may change over time. Results also raise issues surrounding how patients' perceptions influence the course of their disease.  相似文献   
995.
996.
BACKGROUND: Peritubular capillary (PTC) deposition of complement split factor C4d in renal allografts has been shown to be closely associated with circulating antidonor antibodies and a marker for relatively poor graft survival. Monocyte/macrophage (MO) infiltration of renal allografts has been shown to adversely affect graft survival. The purpose of this study was to assess whether the two phenomena are related. METHODS: Twenty-three biopsies (from 15 patients) demonstrated diffuse strong staining of PTC for C4d (C4d+ group) and acute tubular injury with or without significant cellular rejection, while 28 biopsies (with acute rejection) but negative for PTC C4d served as controls (C4d- group). RESULTS: The C4d+ group demonstrated significantly greater glomerular and interstitial MO infiltration than did the C4d- group [3.4 +/- 2.0 vs. 0.2 +/- 0.3 MO/glomerulus, P < 0.0001; 12.9 +/- 9.2 vs. 6.5 +/- 5.0 MO/high power field (hpf), P = 0.0030]. Neutrophilic (PMN) infiltration of glomeruli and PTC was also significantly greater in the C4d+ group than in the C4d- one (0.8 +/- 0.6 vs. 0.3 +/- 0.3 PMN/glomerulus, P = 0.0003; 0.9 +/- 0.8 vs. 0.4 +/- 0.3 PTC PMN/hpf, P = 0.0035). CONCLUSION: The results indicate a close association between PTC C4d deposition and MO infiltration, particularly glomerular, and confirm previous observations regarding the correlation of PTC C4d staining and PMN infiltration.  相似文献   
997.
998.
999.
Application of proteomics technology to the field of neurotrauma   总被引:6,自引:0,他引:6  
Near-completion of the Human Genome Project has stimulated scientists to begin looking for the next step in unraveling normal and abnormal functions within biological systems. Consequently, there is new focus on the role of proteins in these processes. Proteomics is a burgeoning field that may provide a valuable approach to evaluate the post-traumatic central nervous system (CNS). Although we cannot provide a comprehensive assessment of all methods for protein analysis, this report summarizes some of the newer proteomic technologies that have propelled this field into the limelight and that are available to most researchers in neurotrauma. Three technical approaches (two-dimensional gel electrophoresis, direct analysis by mass spectrometry, including two-dimensional chromatography coupled to mass spectrometry and isotope coded affinity tags, and antibody technologies) are reviewed, and their advantages and disadvantages presented. A discussion of proteomic technology in the context of brain and spinal cord trauma follows, addressing current and future challenges. Proteomics will likely be very useful for developing diagnostic predictors after CNS injury and for mapping changes in proteins after injury in order to identify new therapeutic targets. Neurotrauma results in complex alterations to the biological systems within the nervous system, and these changes evolve over time. Exploration of the "new nervous system" that follows injury will require methods that can both fully assess and simplify this complexity.  相似文献   
1000.
OBJECTIVE: Our objective was to compare the sensitivity of unenhanced radiography, CT, and MR imaging in revealing subchondral fractures. SUBJECTS AND METHODS: Forty-five subjects with stage I and stage II osteonecrosis of the femoral head were included in the study as part of a multicenter clinical trial to evaluate the effectiveness of recombinant human bone morphogenetic protein as an adjuvant treatment to core decompression. Patients were evaluated with radiography, CT, and MR imaging 6 and 12 months after surgery. RESULTS: At 6 months, 18 fractures were shown on CT scans, but only 12 were detected on radiographs and six, on MR images. At 12 months, 20 subchondral fractures were detected on CT scans, but only 17 were seen on radiographs and 11, on MR images. Compared with CT, MR imaging has a sensitivity and specificity of 38% and 100%, and unenhanced radiography has a sensitivity and specificity of 71% and 97%, respectively. On T2-weighted MR images, the subchondral fractures were visualized as crescentic high-signal-intensity lines, and in all patients, on the corresponding CT scans, the fracture clearly breached the femoral cortex. CONCLUSION: CT reveals more subchondral fractures in osteonecrosis of the femoral head than unenhanced radiography or MR imaging. The high-signal-intensity line seen on T2-weighted MR images appears to represent fluid accumulating in the subchondral fracture, which may indicate a breach in the overlying articular cartilage.  相似文献   
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