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991.
992.
Shoulder outcome measures: a comparison of 6 functional tests   总被引:1,自引:0,他引:1  
BACKGROUND: Several shoulder function scores are used in research, with no universally adopted standard. This study compares 6 shoulder outcome scales. HYPOTHESIS: Correlations exist between shoulder outcome scales, allowing conversion between scales. Shoulder scales are correlated with age. STUDY DESIGN: Regression and correlation study. METHODS: Seventy subjects with shoulder pain completed 6 shoulder outcome scales. Pearson correlations were calculated between the total scores of the 6 instruments, between the components of the scales, and with age. Regression equations were calculated between scales. RESULTS: The range of r values for total scores was 0.495 < or = r < or = 0.770, P < or = .01. In general, a scale's components were themselves highly correlated and added little new information to the scale (0.260 < or = r < or = 0.705, P < or = .05). Most of the scale scores were highly correlated with age (0.291 < or = r < or = 0.582, P < or = .05). Constant's reported corrections for age reduced (from r = -0.582 to r = -0.250, P < .05) but did not eliminate age as a confounding variable. CONCLUSIONS: Correlations exist between shoulder outcome scales, but existing shoulder scales are not equivalent in their assessments of function; they contain redundant information and, in some cases, may reflect a patient's age better than his/her shoulder function. The utility of conversion equations is minimized as a result of low to moderate correlations between scales.  相似文献   
993.
994.
BACKGROUND: Existing data indicate that non-human leukocyte antigen (HLA) immunogenetic polymorphisms influence the risk of complications after allogeneic hemopoietic stem-cell transplantation. However, prior studies have been limited by small sample size and limited genotyping. METHODS: We examined 22 polymorphisms in 11 immunoregulatory genes including cytokines, mediators of apoptosis, and host-defense molecules by polymerase chain reaction using sequence-specific primers in 160 related myeloablative transplants. Associations were confirmed in two independent cohorts. RESULTS: An intronic polymorphism in the tumor necrosis factor gene (TNF 488A) was associated with the risk of acute graft-versus-host disease (GVHD) (odds ratio [OR] 16.9), grades II to IV acute GVHD (OR 3.3), chronic GVHD (OR 12.5), and early death posttransplant (OR 3.4). Recipient Fas -670G and donor interleukin (IL)-6 -174G were independent risk factors for acute GVHD. Recipient IL-10 ATA and Fas -670 genotype were independent risk factors for chronic GVHD. Recipient IL-1beta +3953T was associated with hepatic acute GVHD, and Fas -670G was associated with major infection. CONCLUSIONS: These results highlight the potential importance of cytokine and apoptosis gene polymorphisms in stem-cell transplantation, and indicate that non-HLA genotyping may be useful to identify individuals at the highest risk of complications and new targets for therapeutic intervention.  相似文献   
995.
Heterogeneous oxygen tension and access to metabolites in solid tumors may produce variability in response to adjuvant therapy. To better understand these microenvironmental features, we examined survival and proliferation of neuroblastoma (NB) cells in an in vitro model of hypoxia and metabolite deprivation. Human NB cells (SH-SY5Y) were subjected to a "self-generated" diffusion gradient of nutrient and oxygen deprivation in a modified in vitro "sandwich model." In this model, the extent of both hypoxia and metabolite deprivation were individually altered, and the effects of each were studied. Cellular proliferation was confirmed by proliferating cell nuclear antigen (PCNA) immunocytochemistry and morphology and hypoxia by vascular endothelial growth factor (VEGF) and pimonidazole immunocytochemistry. We examined apoptotic cell death using TUNEL analysis, assaying for plasma membrane transfer of phosphotidylserine and the presence of the anti-apoptotic protein Bcl-2 using immunocytochemistry. As predicted, cellular survival diminished with increasing duration and severity of hypoxia and metabolite deprivation; oxygen deprivation was determined to be the more important contributory factor to early survival and proliferation. PCNA immunocytochemistry confirmed decreasing fractions of proliferating cells as a function of distance from oxygen and metabolites. VEGF and Bcl-2 immunoreactivity increased with prolonged exposure and increased extent of oxygen/metabolite deprivation. TUNEL analysis and phosphotidylserine transfer demonstrated cellular death of hypoxic and metabolite-deprived NB cells in a manner consistent with a mitochondrial apoptotic pathway. This in vitro model demonstrates that increasing the severity of hypoxia and metabolite deprivation results in diminished proliferation and greater apoptotic death, observations analogous to that of clinical NB tumors.  相似文献   
996.
OBJECTIVE: Surgical aortic valvotomy has a long history of providing excellent palliation for aortic stenosis in infancy and childhood. The fate of aortic valve repairs for dominant aortic regurgitation in this same age group is considerably less clear. METHODS: From 1990 to 2000, a total of 21 patients underwent aortic valve repair for aortic regurgitation at our institution. Seventeen patients were younger than 17 years at the time of repair (3-17 years, mean 8.1 +/- 3.7 years). Of these 17 children, 6 (35%) had bicuspid valves and 11 (65%) had tricuspid valves. Type of repair varied with valve type, but repair generally consisted of commissure resuspension, partial commissure closure, triangular resection of redundant leaflets, or some combination. RESULTS: There were no deaths. Follow-up ranged from 1 to 11 years (mean 5.3 +/- 2.4 years). At present 3 of 17 (17.6%) have mild aortic regurgitation according to echocardiography and 6 (35.2%) have moderate aortic regurgitation. In 8 of 17 cases (47.1%) the repair clearly failed, requiring reoperation from 0.5 to 73 months after the original operation (mean 18.9 months). Reoperation consisted of 6 Ross procedures and 2 mechanical aortic valve replacements. There were no deaths at the secondary operation. CONCLUSION: Aortic valve repair in children with a dominant feature of aortic insufficiency tended to fail progressively and at a high rate. Leaflet thickening was associated with higher risk of repair failure in this series. The threshold for aortic valve replacement should remain low.  相似文献   
997.
As the literature that pertains to botulinum toxin expands, the scope of treatment options broadens. Although initial uses of botulinum toxin focused around the head and neck, there are many uses for the toxin in the area of the foot and ankle; more possibilities are under investigation every day. We review the uses and techniques for botulinum toxin in the foot and ankle and present results of botulinum toxin treatment in 10 idiopathic toe walkers.  相似文献   
998.
Laparoscopic gastric banding is a valuable surgical option for treating morbidly obese patients. Its operative technique is continually being refined. Since its inception, many changes in technique have helped to reduce the complication rate. Currently, the major complications are obstruction, erosion, and band slippage. Band slippage requires surgical correction. Since each band costs approximately 3000 dollars, surgeons should attempt to preserve the band when facing patients with this complication. This paper discusses the techniques for the reduction of band slippage.  相似文献   
999.
1000.
A role for human papillomavirus (HPV) has been suggested in laryngeal squamous cell carcinoma (LSCC). In order to quantitate the available evidence, we reviewed studies examining the risk of laryngeal cancer-associated HPV. PubMed was searched for case-control studies conducted worldwide and published in any language since 1966. Relevant papers were hand-searched and cross-referenced. Six studies met the inclusion criteria. The studies are heterogeneous in the methods used to harvest tissue samples and techniques for detecting the virus within the tissue. HPV-16 positivity among cases ranged from 2.7% to 46.9% and 0-5.7% among controls. Two studies showed a significantly increased risk of LSCC if HPV-16 was present (OR 18.5, 95% CI 2.2-154.8, OR 2.6, 95% CI 1.1-6.0). An increased risk was also observed for glottic versus supraglottic cancer in one study (OR 9.69, 95% CI 1.47-64.04). The direction of effect is towards an increase in risk of LSCC in people with evidence of HPV-16 infection. There is marked heterogeneity in the methods used to detect the virus and frequency with which it is detected. An adequately powered study using a reliable detection technique is required to confirm and quantify this risk and to examine effect modification.  相似文献   
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