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V Douzdjian SS Bhaskar PK Baliga KK Gugliuzza PR Rajagopalan 《Canadian Metallurgical Quarterly》1997,20(8):1310-1314
OBJECTIVE: The racial impact on graft outcome is not well defined in diabetic recipients. The purpose of this study is to analyze our experience with kidney-alone (A) and kidney-pancreas (KP) transplantation in type 1 diabetic recipients and evaluate the impact of racial disparity on outcome. RESEARCH DESIGN AND METHODS: The records of 217 kidney transplants (118 KA, 99 KP) performed on type 1 diabetic patients between 1985 and 1995 at the Medical University of South Carolina and the University of Texas Medical Branch were reviewed. RESULTS: A total of 53 (31%) white patients and 15 (33%) black patients experienced at least one episode of biopsy-proven acute rejection of the renal graft (NS). Patient survival at 1, 2, and 5 years was similar in white (92, 87, 69%) and black (91, 91, 69%) patients (NS). Kidney graft survival at 1, 2, and 5 years in the KA group was 72, 62, and 42% in blacks, compared with 79, 76, and 53% in whites (NS). Kidney graft survival at 1, 2, and 5 years in the KP group was 92, 92, and 74% in blacks, compared with 83, 77, and 58% in whites (NS). Pancreas graft survival at 1, 2, and 5 years was 81, 81, and 81% in blacks, compared with 81, 75, and 62% in whites (NS). Cox regression analysis revealed that donor age > or = 40 years increased the risk of renal graft failure 6.2-fold (P = 0.0001), whereas the addition of a pancreas transplant to a kidney and a living-related transplant decreased the risk of failure of the kidney graft 0.2 (P = 0.005) and 0.1 times (P = 0.005). CONCLUSIONS: Our results suggest that when compared with whites, there may be a trend toward an improved kidney and pancreas graft outcome in blacks undergoing KP transplants. These findings suggest that diabetes may override the risk factors that account for the pronounced disparity in outcome observed between nondiabetic white and black recipients. 相似文献
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The TSIMMIS Approach to Mediation: Data Models and Languages 总被引:18,自引:2,他引:16
Hector Garcia-Molina Yannis Papakonstantinou Dallan Quass Anand Rajaraman Yehoshua Sagiv Jeffrey Ullman Vasilis Vassalos Jennifer Widom 《Journal of Intelligent Information Systems》1997,8(2):117-132
TSIMMIS—The Stanford-IBM Manager of Multiple InformationSources—is a system for integrating information. It offers a datamodel and a common query language that are designed to support thecombining of information from many different sources. It also offerstools for generating automatically the components that are needed tobuild systems for integrating information. In this paper we shalldiscuss the principal architectural features and their rationale. 相似文献
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Solutions, within the framework of linear uncoupled thermoelasticity, are presented for certain problems of flexure of composite laminates. Benchmark numerical results, useful for the validation or otherwise of approximate laminate models, are tabulated. Finally, these results are used to examine the accuracy of the classical lamination theory based on Kirchhoff's hypothesis. 相似文献
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Hemant Ramaswami Atul Modi Sam Anand 《The International Journal of Advanced Manufacturing Technology》2007,31(9-10):857-870
In the wake of growing importance for quality and the need to reduce inspection costs simultaneously, the need for a scientific method of selecting an optimum inspection strategy for coordinate measuring machine (CMM) based inspection has become very important. The inspection error resulting from CMM inspection is greatly affected by the profile irregularities and the sampling strategy, which includes sample size, sampling methods, and algorithms used for form evaluation. This paper describes a system that can recommend an optimal inspection plan based on the needs of the user. A design of experiments (DOE) based approach is used to relate the inspection error with sampling strategies. Surface irregularities are included in the form of lobes formed on the profile. A new two-way model is proposed that works in both directions between the sampling strategy and the performance metrics. The results indicate that the number of lobes and the sampling method used have little impact on the inspection error, while the sample size and form evaluation algorithms have a significant influence. An inspection plan advisor is presented, which provides an inspection plan based on the estimated shape and acceptable measurement error. 相似文献
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With worldwide energy consumption rising, there is a need to reduce energy use of the housing stock. While this general idea is well-known, there is an overwhelming amount of product data and manufacturers claims through which the homebuilder or designer must sort to make informed selections of energy-efficient upgrades. The main objective of this research was to identify cost effective–energy efficient upgrades from a group of 16 commonly available choices, and rank them according to the most beneficial for the least cost. This study was conducted in Phoenix, Arizona, and included a sample of 30 production-style homes typical of the Phoenix metropolitan area. Energy-simulation software was used to perform energy evaluations and derive the benefits of each upgrade. The cost of each upgrade was obtained from a database of national average costs and from a local context. Differences in the selection of beneficial upgrades vary dramatically with the source of the cost information. This research provides a generic methodology that can be used by builders and designers to select appropriate energy-efficient upgrades for a given geographic area that will provide high operating benefits relative to the amount of capital investment. 相似文献
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The hydrothermal treatment of two different wood biomass samples such as cherry (hard wood) and cypress (soft wood), whose composition is different i.e. lignin, cellulose and hemicellulose were performed at 280 °C for 15 min with aq. K2CO3 with different concentrations (0–1 M). The soft wood biomass contains higher lignin content than hard wood biomass. The cellulose rich cherry wood biomass produced higher proportion of acetic acid than cypress. The lignin rich cypress produced the hydrocarbons with major portion of phenolic hydrocarbons and derivatives than cherry. The total oil yields from both cherry and cypress wood biomass produced 50 wt% of liquid hydrocarbons at 280 °C for 15 min with 0.5 M K2CO3 solution. The volatility distribution of liquid hydrocarbons showed the characteristic features of soft and hard wood biomasses. 相似文献
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Changes in the NHS have supported the idea of targeting health services to those in greatest need. This has meant that health visitors are increasingly having to identify 'vulnerable' families in need of increased health visiting intervention. This paper reports on a qualitative study undertaken in order to explore the ways in which health visitors plan and organize their work in relation to the concept of vulnerability. Focus groups and semi-structured interviews were carried out with health visitors from two separate geographical areas, one an inner city area and the other suburban, in order to explore the criteria by which health visitors define vulnerability and decide to increase their levels of intervention to particular families. It was found that vulnerability was extremely difficult to define but that the health visitors used criteria which were appropriate to the particular localities in which they worked to identify vulnerable families and to increase their levels of intervention to those families. Health visitors were targeting their services within a framework of a basic minimum service to all and were assessing the health needs of individuals or families rather than planning their work on the basis of community or practice profiles. 相似文献