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111.
BACKGROUND: The incidence of recurrence of haemolytic-uraemic syndrome (HUS) in renal allografts appears to vary by centre, with the highest rates reported from the University of Minnesota. It is possible that the high rate of HUS recurrence at this institution reflects a transplant population skewed towards patients with a form of HUS that is more likely to recur in the allograft. METHODS: This study examined whether the initial episode of HUS in the native kidneys was preceded by a diarrhoeal prodrome ('classical HUS') or not ('atypical HUS'), and evaluated transplant outcomes in 24 patients who received 36 transplants at the University of Minnesota between 31 May 1972 and 31 December 1994. RESULTS: Eighteen of the 24 patients had atypical HUS, three had classical HUS, and in three patients the presence or absence of a diarrhoeal prodrome could not be determined. Recurrent HUS, defined as microangiopathic haemolytic anaemia, thrombocytopenia, renal insufficiency, and allograft biopsy findings compatible with HUS, occurred 16 times in 14 grafts in 11 patients. Nine of these patients had atypical HUS, one had classical HUS, and in one the nature of the prodrome could not be determined. Eleven of the 14 initial recurrences took place within 2 months of transplant. Recurrence was not more frequent in patients who received cyclosporin or antilymphocyte preparations. Actuarial analysis using matched controls showed poorer graft survival in patients with a primary diagnosis of HUS (P = 0.007), due to the high frequency of graft loss in HUS patients with recurrence. CONCLUSION: Based upon these data and a review of the literature, it can be concluded that the risk of recurrence of HUS in the allograft is confined almost entirely to patients with atypical forms of HUS.  相似文献   
112.
The pancreas is an ideal organ for adenoviral gene therapy because of the high level of gene transfer that can be achieved and because of the many diseases that can potentially be treated using this technology. In this report, we characterize the immune response to direct pancreatic injection of adenovirus and we overcome some of the limitations it imposes by using immunosuppression. Direct injection of recombinant adenovirus into the pancreas leads to the production of neutralizing antibodies and to sensitized splenocytes which engage in increased cytotoxic, lymphoproliferative, and cytokine release activity when reexposed to adenovirus. Transgene expression is transient and the vector cannot be readministered. Deletion of CD4+ T helper cells improves expression over time (40% of pancreatic cells express transgene at day 28 vs. 5% in controls), and allows the vector to be readministered in the pancreas, albeit, inefficiently, when compared to naive animals. Similarly, blockade of CD40 ligand, which preserves the CD4+ T helper cell population, also improves expression over time (30% of pancreatic cells express transgene at day 28), and allows the vector to be readministered. With both approaches, neutralizing antibodies are decreased and the remaining splenocytes do not engage in activated immune responses. Thus, local delivery of the adenoviral vector induces a systemic response that prevents pancreatic readministration, even with direct injection. Blockade of CD40 ligand and T helper cell depletion are transient regimens that induce systemic immunosuppression. Until the development of newer strategies that selectively suppress adenoviral immune responses, these are viable alternatives for enhancement of pancreatic adenoviral delivery.  相似文献   
113.
Replicated D. T. Lykken's study (see record 1968-18058-001) to resolve the conflict between the findings of S. R. Maddi et al (see record 1987-22446-001) and those of D. H. Schroeder and P. T. Costa (see record 1984-23643-001) regarding the impact of negative affectivity (NA; i.e., neuroticism) contaminated life event items on observed life event–illness relationships. Among 330 managers and professionals, NA-contaminated items correlated significantly with 3 measures of well-being (depression, life satisfaction, and physical symptoms). In 2 of 3 cases, correlations between contaminated items and well-being measures were significantly different from correlations between uncontaminated items and well-being indicators. Prior life event–well-being findings may be inflated considerably by the use of NA-contaminated events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
114.
This paper investigates the impact of heterogeneity at the land surface on geophysical parameters retrieved from multiangle microwave brightness temperature data, such as would be obtained from the Soil Moisture and Ocean Salinity (SMOS) mission. Synthetic brightness temperature data were created using the Common Land (land surface) Model, coupled with a microwave emission model and set within the framework of the North American Land Data Assimilation System (NLDAS). Soil moisture, vegetation optical depth, and effective physical temperature were retrieved using a multiobjective calibration routine similar to the proposed SMOS retrieval algorithm for a typical on-axis range of look angles. The impact of heterogeneity both in the near-surface profiles of soil moisture and temperature and in the land cover on the accuracy of the retrievals was examined. There are significant errors in the retrieved parameters over regions with steep gradients in the near-surface soil moisture profile. These errors are approximately proportional to the difference in the soil water content between the top (at 0.7 cm) and second layer (at 2.7 cm) of the land surface model. The errors resulting from heterogeneity in the land cover are smaller and increase nonlinearly with increasing land-surface heterogeneity (represented by the standard deviation of the optical depth within the pixel). The most likely use of retrieved soil moisture is through assimilation into an LDAS for improved initiation of weather and climate models. Given that information on the soil moisture profile is already available within the LDAS, the error in the retrieved soil moisture as a result of the near-surface profile can be corrected for. The potential errors as a result of land-surface heterogeneity can also be assessed for use in the assimilation process.  相似文献   
115.
Elevated-temperature fracture toughness properties were developed on ex-service 2-l/4Cr-1Mo steel weldments. Fracture toughness was measured on both base and heat-affected zone (HAZ) metals. A composite specimen consisting of base, HAZ, and weld metals was used to develop fracture toughness properties in the HAZ area. It was observed that the J-R curve of the HAZ was significantly lower than that of the base metal. Increasing crack extension increased the difference between theJ-R curves of the base metal and the HAZ. Dimpled fracture was the prime fracture mode in the base metal specimen, and a mixed-mode (ductile and “granular”) fracture was found in the HAZ specimens. Scanning transmission electron microscopy (STEM) examination revealed significant intergranular carbide precipitation and agglomeration within the HAZ. The lower fracture toughness of the HAZ, as compared to the base metal, was attributed to the large accumulation of carbides in the grain boundaries of the HAZ, which weakened the grain boundaries and caused “granular” fracture.  相似文献   
116.
Currently environmental management is at the forefront of small and medium-sized enterprises (SMEs), especially in certain sectors where its presence is mandatory in order to operate in business. Although SMEs in certain sectors are catching up on their larger counterparts in reducing their environmental impacts, which are mainly due to supply chain demands, statistics clearly show that the majority of manufacturing SMEs are not incorporating formal environmental management system (EMS) into their businesses. The treatment of SMEs as one homogenous group by research has led to a lack of providing real strategies and tools that SMEs can implement and use. Current strategies are fragmented and seen as piecemeal, requiring adaptation and application to a particular sector by SMEs. SMEs do not have the resources required to research all environmental aspects of their businesses, which is a fundamental part of an EMS. Irish EMS support initiatives have but provided grant assistance in contributing towards the fees of external environmental consultants. As a result the majority of SMEs must rely on the help and assistance of external environmental consultants to assist them in taking account of their environmental impacts. Recent research obtained data on the current practices and experiences of Irish SMEs in areas of manufacturing and environmental management. Results of which, compares with previous research carried out in other European countries, however their significance and weightings differ considerably. Responses obtained regarding waste minimisation, recycling and reuse were positive, however, Irish manufacturing SMEs are falling short of initiating formal environmental management systems and front of pipe technologies. The use of information technology in assisting SMEs manage their environmental impacts holds much potential in providing a complete holistic environmental information management system (EIMS), which is already implemented in larger companies. Initial research has identified and developed proven strategies, solutions and tools from ISO 14001 certified Engineering SMEs, which will be used to form an initial base for an EIMS.  相似文献   
117.
118.
The findings are presented of a conference on Outcomes of Hand Surgery organized by the audit committee of British Society for Surgery of the Hand in 1993. Measures of outcome in terms of movement, power, sensibility, pain, activities of daily living, complications and patient satisfaction are considered, and an example of a patient evaluation measure given as an appendix.  相似文献   
119.
The authors present a new method to locate the tumor bed after lumpectomy. The method relies on accumulation of Ga-67 at the surgical site. This technique was useful in identifying the tumor bed in six candidates for breast conserving surgery and radiation therapy. This method may be applicable in other soft tissue malignancies that require postoperative radiation.  相似文献   
120.
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