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61.
BackgroundTotal shoulder arthroplasty (TSA) is an increasingly common treatment for end-stage glenohumeral osteoarthritis. Current established radiographic measures and classification systems do not predict patient-reported outcomes from TSA. We hypothesized that the MRI-based Shoulder Osteoarthritis Severity (SOAS) Score would correlate with subjective improvement following TSA.MethodsPatients undergoing TSA with preoperative shoulder MRIs and pre- and postoperative ASES scores with minimum 2-year follow-up were included from a prospectively collected institutional shoulder arthroplasty database. SOAS scores, which is measured from 0 to 100 with an increasing score reflecting greater global degenerative changes, were assessed by two independent reviewers, and Samilson-Prieto grade and Walch classification were scored by one reviewer. Average SOAS scores were correlated with demographic factors and pre-, post-, and change (Δ) in ASES scores. Statistical analysis was performed with STATA with Pearson's correlation, one-way ANOVA, and ROC analysis, with significance defined by p <.05.Results30 patients (age 63 ± 10 years, 14 females, 16 males) who underwent primary anatomic TSA were included. The intraclass correlation coefficient (ICC) for total SOAS scores calculated by reviewers was 0.91. SOAS score correlated significantly with ΔASES (r = 0.61, p = .0003) and preoperative ASES (r = -0.37, p = .042), with greater MRI-based degenerative change associated with greater improvement after TSA and lower preoperative ASES score. No significant relationship was found between either Samilson-Prieto or Walch classification and SOAS or ASES scores. No significant relationship was found between SOAS scores and age, sex, or BMI. Using an MCID of 21 as previously reported, an ROC curve was generated and found to have an AUC of 0.96. A SOAS score cut-point of 36.25 was found to maximize sensitivity and specificity in predicting reaching MCID.ConclusionWe observed a significant positive correlation between the MRI-based SOAS score and functional improvement following TSA measured using change in ASES scores, indicating that patients with more advanced degenerative changes on MRI had greater improvement after shoulder replacement surgery. We found that the correlation strength was highest when comparing total SOAS score to ΔASES as opposed to any individual sub-component of the SOAS score. The MRI-based SOAS score for shoulder osteoarthritis may be a valuable tool for predicting patient outcomes following TSA.Level of evidenceLevel III; Retrospective Cohort Comparison; Prognosis Study  相似文献   
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In early 2004, an evidence-based prenatal care workshop was held for community health nurses working in First Nations communities in British Columbia. The purpose of the workshop was to begin a dialogue on the use of evidence to improve prenatal care in First Nations communities. Specifically, selected models of knowledge transfer to improve care were introduced and discussed. Of the 81 nurses who participated, 52 completed a feedback questionnaire. Most of the participants (73%) were community health nurses. They worked across diverse geographic settings and health-care administration models (federally managed, band managed, tribal council managed). Seventy-three per cent of the nurses reported that a participatory model of knowledge transfer was important or very important. They also identified priority target audiences (stakeholders) for knowledge transfer strategies. Exploring stakeholders' views, values and priorities related to prenatal care and creating informal dialogue among these groups was identified as a next step in participatory transfer and exchange of knowledge to improve prenatal care in First Nations communities.  相似文献   
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OBJECTIVES: Prevalence of single quinolone-resistance determining region (QRDR) mutations in Streptococcus pneumoniae was studied from nine institutions over 5 years to track the incidence of single QRDR mutations. METHODS: All 1106 levofloxacin-susceptible pneumococci (MICs < or = 2.0 mg/L) identified from 1112 total isolates (99.5% susceptibility) in TRUST 3 (1999), TRUST 5 (2001) and TRUST 7 (2003) surveillance studies from the same nine hospitals in nine states were screened for QRDR mutations. Using pyrosequencing, the strains were screened for mutations corresponding to hot spots Asp-78, Ser-79 and Asp-83 in ParC; Asp-80, Ser-81 and Glu-85 in GyrA; Asp-435 in ParE and Asp-435 in GyrB. DNA sequencing of QRDRs was performed to confirm mutations. RESULTS: No QRDR mutations were found in any of the isolates with levofloxacin MICs < or = 0.5 mg/L and no gyrA or gyrB QRDR mutations were found in any of the screened isolates (MICs < or = 2 mg/L). Four single-step QRDR mutants with the following amino acid substitutions were found: ParE Asp-435 to Asn (isolated in 1999 in Colorado); ParC Asp-83 to Asn (isolated in 2001 in Kentucky); ParC Ser-79 to Phe (isolated in 2003 in Indiana) and ParC Ser-79 to Tyr (isolated in 2003 in California). These non-clonal strains had levofloxacin MICs of 1 mg/L and were non-susceptible to ciprofloxacin (MIC 2-4 mg/L). CONCLUSIONS: Overall prevalence of single QRDR mutations in levofloxacin-susceptible S. pneumoniae with MICs of < or = 2 mg/L was 0.4% (4/1106) and has remained <1% within nine institutions over 5 years (1999-2003).  相似文献   
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To assess the metabolic consequences of the diversion of the pancreatic venous drainage to the systemic circulation, the pancreaticoduodenal and gastrosplenic veins were anastomosed to the inferior vena cava in nine normal dogs. This procedure maintained the integrity of the entire pancreas while shunting the hormonal output of the pancreas to the periphery. The metabolic effects were assessed from the sensitivity to insulin during a euglycemic hyperinsulinemic glucose clamp using an insulin infusion of 800 microU/kg per min. The studies were controlled by their duplication in seven dogs identically treated but with the pancreatic veins reanastomosed to the portal vein. No differences in systemic insulin levels or insulin sensitivity before and after surgery were seen under these circumstances. After diversion, however, basal insulin levels rose from 4.5 +/- 1.0 to 11.5 +/- 2.5 microU/ml. Basal glucose metabolic clearance rate (MCR) rose to 3.0 +/- 0.4 from 2.0 +/- 0.3 ml/kg per min. On insulin infusion, maximal stimulation of MCR within the 2-h infusion period was to 15.2 +/- 2.5 ml/kg per min preoperatively and to 7.2 +/- 0.8 ml/kg per min after diversion. Using ratios of MCR-to-insulin concentration as an index of insulin sensitivity, it was demonstrated that this index decreased by at least 50% after diversion. These data imply that portal venous drainage of the pancreas is an important factor in the determination of peripheral insulin sensitivity.  相似文献   
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