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Objective—Evaluation of the centrifugal pump vs roller pump concerning effects upon platelet function, hemolysis and clinical outcome in elective coronary artery bypass surgery.

Design—Thirty‐four patients were randomized to centrifugal or roller pump. Platelet activation was studied by flow cytometry before, during and up to 3 days after bypass.

Results—Duration of bypass, ischemic period, peripheral anastomoses, hospital stay and mortality did not differ. In roller pump patients, platelet aggregates increased by 250% between end of bypass and 3?h postoperatively (p?<?0.001). A secondary, fivefold increase in number of platelet aggregates was found on the 3rd postoperative day (p?<?0.001). In the centrifugal pump group, these changes were not significant. Hemolysis increased (20%) at end of bypass and 3?h postoperatively (p?<?0.005), and decreased to preoperative levels the next day without group difference.

Conclusion—Platelet aggregation was significantly increased in roller compared with centrifugal pump patients, indicating higher susceptibility to postoperative thrombotic complications with the roller pump. Otherwise, there was no clinical evidence for superiority of the centrifugal pump.  相似文献   
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BackgroundDiagnostics that involve the use of oral fluids have become increasingly available commercially in recent years and are of particular interest because of their relative ease of use, low cost and noninvasive collection of oral fluid for testing.Types of Studies ReviewedThe authors discuss the use of salivary diagnostics for virus detection with an emphasis on rapid detection of infection by using point-of-care devices. In particular, they review salivary diagnostics for human immunodeficiency virus, hepatitis C virus and human papillomavirus. Oral mucosal transudate contains secretory immunoglobulin (Ig) A, as well as IgM and IgG, which makes it a good source for immunodiagnostic-based devices.Clinical ImplicationsBecause patients often visit a dentist more regularly than they do a physician, there is increased discussion in the dental community regarding the need for practitioners to be aware of salivary diagnostics and to be willing and able to administer these tests to their patients.  相似文献   
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Objectives

Rank Preserving Structural Failure Time models are one of the most commonly used statistical methods to adjust for treatment switching in oncology clinical trials. The method is often applied in a decision analytic model without appropriately accounting for additional uncertainty when determining the allocation of health care resources. The aim of the study is to describe novel approaches to adequately account for uncertainty when using a Rank Preserving Structural Failure Time model in a decision analytic model.

Methods

Using two examples, we tested and compared the performance of the novel Test-based method with the resampling bootstrap method and with the conventional approach of no adjustment. In the first example, we simulated life expectancy using a simple decision analytic model based on a hypothetical oncology trial with treatment switching. In the second example, we applied the adjustment method on published data when no individual patient data were available.

Results

Mean estimates of overall and incremental life expectancy were similar across methods. However, the bootstrapped and test-based estimates consistently produced greater estimates of uncertainty compared with the estimate without any adjustment applied. Similar results were observed when using the test based approach on a published data showing that failing to adjust for uncertainty led to smaller confidence intervals.

Conclusions

Both the bootstrapping and test-based approaches provide a solution to appropriately incorporate uncertainty, with the benefit that the latter can implemented by researchers in the absence of individual patient data.  相似文献   
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Abstract

Objective: Despite immense popularity of Jaipur foot as low cost prosthetic, not much work has been reported on its design for manufacturing standardization. Without manufacturing standardization, it cannot be mass produced using contemporary manufacturing technologies. The objective of this work is to carry out its computer aided design (CAD) followed by computer aided engineering (CAE) based on the material properties obtained from the previous work [1 Rachel HT, Kristine MF, Benjamin BW, et al. Assessment of the compressive and tensile mechanical properties of materials used in the Jaipur foot prosthesis. Prosthet Orthot Int. 2018;42:511517.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]] of the authors. This may lead to the possible use of modern manufacturing processes for the Jaipur foot design.

Design: After modelling using CAD tool including its organic surfaces, the designed foot was analysed using a CAE tool for balanced standing load conditions to determine maximum stresses and deformation in its various parts. The bending analysis was done to check the dorsiflexion movement so that the strained sections could be identified for more reliable and durable prosthetic foot. For the static load analysis, base of the foot was constrained and 300–500 N load was applied through the bolt whereas for bending, the part near the bolt was fixed and pressure was applied at junction of front foot and toes.

Results: The results show that the maximum stress and deformation occur at the bolt, while the skin undergoes maximum strain. CAE analysis also proves the robustness of the Jaipur foot design and a well manufactured Jaipur foot as per standardized design should be able to withstand the real life conditions without failure. The CAD model is also used for FDM based printing for a nonfunctional prototype of Jaipur foot.
  • Implications for rehabilitation
  • The results of this study will serve as an important guideline for further research regarding equivalent material replacement, material optimization and obtaining an optimized design after studying the foot for dynamic analysis.

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