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Introduction Early screening of physical and psychosocial risk factors has been advocated as a way to identify low back pain (LBP) patients who may develop chronic disability. This study evaluated the predictive validity of a Chinese version of the Orebro Musculoskeletal Pain Questionnaire (OMPQ) in identifying LBP patients at risk of developing poor return-to-work (RTW) outcomes. Methods Altogether 241 patients with acute or subacute non-specific LBP agreed to participate, and they were screened at baseline with OMPQ, and evaluated after discharge from physiotherapy (n = 173) with outcome measures including the Roland–Morris Disability Questionnaire (RMDQ), numerical pain score (0–10) and global recovery (0–10). At 1-year follow-up, information on RTW status as well as sick leave duration were obtained. Results At baseline the OMPQ had a mean score of 112.0 (SD = 26.5). The receiver operator characteristic (ROC) curves of OMPQ scores at 1-year follow-up recorded values of area under the curve of 0.693 for RTW and 0.714 for sick leave duration, which are comparable to those reported in European studies. OMPQ was the only factor that could significantly predict the RTW outcomes, compared to other variables such as the RMDQ scores. Conclusion The results confirmed the predictive validity of the Chinese version of OMPQ in screening LBP patients at risk of developing poor occupational outcomes, and appropriate interventions can be arranged for these high-risk individuals in the rehabilitation process.  相似文献   
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Variable clinical responses, tumor heterogeneity, and drug resistance reduce long-term survival outcomes for metastatic melanoma patients. To guide and accelerate drug development, we characterized tumor responses for five melanoma patient derived xenograft models treated with Vemurafenib. Three BRAFV600E models showed acquired drug resistance, one BRAFV600E model had a complete and durable response, and a BRAFV600V model was expectedly unresponsive. In progressing tumors, a variety of resistance mechanisms to BRAF inhibition were uncovered, including mutant BRAF alternative splicing, NRAS mutation, COT (MAP3K8) overexpression, and increased mutant BRAF gene amplification and copy number. The resistance mechanisms among the patient derived xenograft models were similar to the resistance pathways identified in clinical specimens from patients progressing on BRAF inhibitor therapy. In addition, there was both inter- and intra-patient heterogeneity in resistance mechanisms, accompanied by heterogeneous pERK expression immunostaining profiles. MEK monotherapy of Vemurafenib-resistant tumors caused toxicity and acquired drug resistance. However, tumors were eradicated when Vemurafenib was combined the MEK inhibitor. The diversity of drug responses among the xenograft models; the distinct mechanisms of resistance; and the ability to overcome resistance by the addition of a MEK inhibitor provide a scheduling rationale for clinical trials of next-generation drug combinations.  相似文献   
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Aim Surgical site infection (SSI) remains a common postoperative morbidity, particularly in colorectal resections, and poses a significant financial burden to the healthcare system. The omission of mechanical bowel preparation, as is performed in enhanced recovery after surgery programmes, appears to further increase the incidence. Various wound protection methods have been devised to reduce the incidence of SSIs. However, there are few randomized controlled trials assessing their efficacy. The aim of this study is to investigate whether ALEXIS wound retractors with reinforced O‐rings are superior to conventional wound protection methods in preventing SSIs in colorectal resections. Methodology Patients undergoing elective open colorectal resections via a standardized midline laparotomy were prospectively randomized to either ALEXIS or conventional wound protection in a double‐blinded manner. A sample size of 30 in each arm was determined to detect a reduction of SSI from 20% to 1% with a power of 80%. Secondary outcomes included postoperative pain. The operative wound was inspected daily by a specialist wound nurse during admission, and again 30 days postoperatively. Statistical analysis was performed using spss version 13 with P < 0.05 considered significant. Results Seventy‐two patients were recruited into the study but eight were excluded. There were no SSIs in the ALEXIS study arm (n = 34) but six superficial incisional SSIs (20%) were diagnosed in the control arm (P = 0.006). Postoperative pain score analysis did not demonstrate any difference between the two groups (P = 0.664). Conclusion The ALEXIS wound retractor is more effective in preventing SSI in elective colorectal resections compared with conventional methods.  相似文献   
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