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11.
This study compared the push‐out bond strength of mineral trioxide aggregate (MTA) and a new endodontic cement (NEC) as root‐end filling materials in root‐end cavities prepared by ultrasonic technique (US) or Er,Cr:YSGG laser (L). Eighty single‐rooted extracted human teeth were endodontically treated, apicectomised and randomly divided into four following groups (n = 20): US/MTA, US/NEC, L/MTA and L/NEC. In US/MTA and US/NEC groups, root‐end cavities were prepared with ultrasonic retrotip and filled with MTA and NEC, respectively. In L/MTA and L/NEC groups, root‐end cavities were prepared using Er,Cr:YSGG laser and filled with MTA and NEC, respectively. Each root was cut apically to create a 2 mm‐thick root slice for measurement of bond strength using a universal testing machine. Then, all slices were examined to determine the mode of bond failure. Data were analysed using two‐way anova . Root‐end filling materials showed significantly higher bond strength in root‐end cavities prepared using ultrasonic technique (US/MTA and US/NEC) (P < 0.001). The bond strengths of MTA and NEC did not differ significantly. The failure modes were mainly adhesive for MTA, but cohesive for NEC. In conclusion, bond strengths of MTA and NEC to root‐end cavities were comparable and higher in ultrasonically prepared cavities.  相似文献   
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The goal of this meta-analysis was to evaluate the efficacy of venous foot pumps in prevention of venous thromboembolism following joint arthroplasty. Using different databases, we found 13 prospective clinical trials published meeting our inclusion criteria. In total, 1514 patients were included in the final analysis. Venous foot pump devices are effective in prevention of venous thromboembolic disease after total hip and knee arthroplasty compared to chemoprophylaxis. This was especially significant in prevention of major deep vein thrombosis and pulmonary emboli rate. The use of mechanical devices like venous calf or foot pump, either alone or in combination with less potent chemical prophylaxis, on the other hand can reduce the rate of venous thromboembolism and complications of potent chemoprophylaxis like wound hematoma.  相似文献   
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To reduce study start‐up time, increase data sharing, and assist investigators conducting clinical studies, the National Institute of Neurological Disorders and Stroke embarked on an initiative to create common data elements for neuroscience clinical research. The Common Data Element Team developed general common data elements, which are commonly collected in clinical studies regardless of therapeutic area, such as demographics. In the present project, we applied such approaches to data collection in Friedreich's ataxia (FRDA), a neurological disorder that involves multiple organ systems. To develop FRDA common data elements, FRDA experts formed a working group and subgroups to define elements in the following: ataxia and performance measures; biomarkers; cardiac and other clinical outcomes; and demographics, laboratory tests, and medical history. The basic development process included identification of international experts in FRDA clinical research, meeting by teleconference to develop a draft of standardized common data elements recommendations, vetting of recommendations across the subgroups, and dissemination of recommendations to the research community for public comment. The full recommendations were published online in September 2011 at http://www.commondataelements.ninds.nih.gov/FA.aspx . The subgroups′ recommendations are classified as core, supplemental, or exploratory. Template case report forms were created for many of the core tests. The present set of data elements should ideally lead to decreased initiation time for clinical research studies and greater ability to compare and analyze data across studies. Their incorporation into new, ongoing studies will be assessed in an ongoing fashion to define their utility in FRDA. © 2012 Movement Disorder Society  相似文献   
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Background

Sinonasal undifferentiated carcinoma (SNUC) is a very rare entity with a poor prognosis. Due to the lack of studies on the subject, evidence is lacking concerning its management.

Methods

A multicenter collaborative study was conducted to assess treatment strategy, oncological outcome, and prognostic factors.

Results

Definitive analyses focused on 54 patients with a majority of advanced stage; the 3‐year overall survival (OS) and 3‐year recurrence‐free survival (RFS) rates were, respectively, 62.4% and 47.8%. During the follow‐up, 18 patients (33.3%) died, 10 (18.5%) developed metastases, 7 had lymph‐node involvement (13%), and 12 (22.2%) showed recurrence or local progression. In univariate analyses, treatment modalities associated with improved RFS were induction chemotherapy (p = 0.02) and intensity‐modulated radiotherapy (p = 0.007). In the multivariate analyses, only induction chemotherapy (p = 0.047, hazard ratio [HR] = 0.39) was significantly associated with improved RFS.

Conclusion

Multimodal therapies including induction chemotherapy and intensity‐modulated radiotherapy may improve the prognosis of SNUC; surgery might improve local control. Further multicenter studies are required.
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Global healthcare expenditure is increasing, along with the numbers of older patients with multiple comorbidities, while the numbers of health workers are hugely decreasing, and many nursing and midwifery vacancies remain unfilled. With the World Health Organization declaring 2020 the Year of the Nurse and Midwife, and commencing the Nursing Now campaign with partners including the International Council of Nurses and the International Confederation of Midwives, has allowed these professions to unite, encourage advocacy and the call for global investment in nursing and midwifery. These actions will permit these professions to address universal health coverage, global inconsistencies of professional practice, and recruitment and retention. The Nightingale Challenge seeks to place early career nurses and midwives at the forefront of transformation, calling on employers worldwide to invest and provide nursing leadership development, and to become a key part of the solution to address the issues of providing universal health coverage, promoting gender equality and supporting economic growth. This will help place them at the heart of tackling 21st century health challenges.  相似文献   
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