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151.
The Helix pomatia agglutinin (HPA)-binding glycoproteins from primary breast cancers and their metastases were compared with appropriate normal control tissues on Western blots. From these studies a single glycoprotein of 55 kDa was found to bind HPA in tumours but not in normal control tissues. The glycoprotein was identified by protein sequencing as being homologous to human immunoglobulin heavy chain variable region. Subsequent immunostaining showed it to be immunoglobulin subclass A. IgA1 was purified from both tumour and normal tissue by affinity chromatography. It was demonstrated that IgA1 from tumour tissue bound HPA whereas IgA1 from normal tissue did not. The oligosaccharides were cleaved from the protein backbone and the glycans from the HPA-binding glycoform of IgA1 were compared with those from normal human IgA1. IgA1 from tumour tissue appears to be associated with an HPA-binding glycan which is not present on the normal tissue-derived IgA1. 相似文献
152.
153.
Requirement of vascular integrin alpha v beta 3 for angiogenesis 总被引:2,自引:0,他引:2
Angiogenesis depends on the adhesive interactions of vascular cells. The adhesion receptor integrin alpha v beta 3 was identified as a marker of angiogenic vascular tissue. Integrin alpha v beta 3 was expressed on blood vessels in human wound granulation tissue but not in normal skin, and it showed a fourfold increase in expression during angiogenesis on the chick chorioallantoic membrane. In the latter assay, a monoclonal antibody to alpha v beta 3 blocked angiogenesis induced by basic fibroblast growth factor, tumor necrosis factor-alpha, and human melanoma fragments but had no effect on preexisting vessels. These findings suggest that alpha v beta 3 may be a useful therapeutic target for diseases characterized by neovascularization. 相似文献
154.
Programs are no longer constrained to execute on the nodes where they reside, and many systems therefore support code mobility. Although mobile code has yet to fully realize its promise of increased system flexibility, scalability, and reliability, the marketplace has embraced mobile code implementations such as Java.Jini, PostScript, and .NET. Several mobile code paradigms exist, and mobile code use raises many security concerns. Here, we map a taxonomy of mobile code paradigms to a taxonomy of network security vulnerabilities, revealing that many important security issues are being ignored. 相似文献
155.
Over many years NPL has carried out measurements of surface tension of steels using the levitated drop method. Much of this work has been to study variations in weld profile brought about by changes in Marangoni flow patterns in the liquid pool, and many of these data have remained unpublished. 49 ferritic and austenitic steels are compared, and relationships for surface tension, and the coefficient of surface tension against temperature, based on sulphur content of the steel, are presented. Data has been reassessed using the Cummings correction to allow for the effects of the levitation forces. 相似文献
156.
Jianghua Li Nikolas Provatas Geoff Brooks 《Metallurgical and Materials Transactions B》2005,36(2):293-302
The melting rate of steel bars with various sizes, shapes, and initial temperatures in a 70 kg liquid steel bath (1650 °C)
was measured to investigate the kinetics involved in steel scrap melting. Our measurements revealed that a solidified shell
was formed around the original bar immediately after it was immersed into the liquid steel. This shell and an associated interfacial
gap generated between it and the original bar were found to be critical to the melting kinetics. We also found that the total
melting time decreased linearly with increasing initial bar temperature. The melting process was simulated using a two-dimensional
phase-field model that considered heat convection with a constant heat-transfer coefficient. Our simulations were in good
agreement with our experiments and showed that the heat conduction associated with the interfacial gap was one of the most
important physical aspects controlling the melting of steel scrap. 相似文献
157.
Aspiration pneumonia following surgically placed feeding tubes 总被引:1,自引:0,他引:1
KA Fox RA Mularski MR Sarfati ME Brooks JA Warneke GC Hunter WD Rappaport 《Canadian Metallurgical Quarterly》1995,170(6):564-6; discussion 566-7
BACKGROUND: The enteral route is preferred in surgical patients requiring nutritional support; however, controversy surrounds the choice of location of feeding tube placement. Although jejunostomy has been commonly accepted as superior to gastrostomy for long-term nutritional support because of an assumed lower risk of aspiration pneumonia, recent studies suggest that reevaluation of common practices of surgical tube placement is warranted. PATIENTS AND METHODS: We conducted a retrospective chart review of gastrostomy and jejunostomy procedures from 1986 to 1993. Demographic information and complications related to the procedure were reviewed. Aspiration pneumonia was defined as respiratory symptoms, leukocytosis, and infiltrate on chest radiograph. RESULTS: Sixty-nine gastrostomies and 86 jejunostomies were performed during the study period. Six patients were diagnosed with aspiration pneumonia; 2 cases of which occurred with jejunostomy and 4 cases occurred with gastrostomy (P = not significant). CONCLUSIONS: There was no difference in rates of pulmonary aspiration or other complications between gastrostomy and jejunostomy. We suggest that when a surgically placed feeding tube is required, the determination of appropriate procedure be based on clinical factors such as the technical difficulty of the operation or long-term feeding goals. 相似文献
158.
Increasing the involvement of clinicians in decision-making is a key part of recent NHS policy. One model designed to increase involvement is shared governance. This article describes the approach to shared governance developed at Kettering General Hospital. Ongoing evaluation of the scheme suggests benefits in terms of personal and professional development for those involved. 相似文献
159.
Timothy Horiuchi Wyeth Bair Brooks Bishofberger Andrew Moore Christof Koch John Lazzaro 《International Journal of Computer Vision》1992,8(3):203-216
We have designed, built and tested a number of analog CMOS VLSI circuits for computing 1-D motion from the time-varying intensity values provided by an array of on-chip phototransistors. We present experimental data for two such circuits and discuss their relative performance. One circuit approximates the correlation model while a second chip uses resistive grids to compute zero-crossings to be tracked over time by a separate digital processor. Both circuits integrate image acquisition with image processing functions and compute velocity in real time. For comparison, we also describe the performance of a simple motion algorithm using off-the-shelf digital components. We conclude that analog circuits implementing various correlation-like motion algorithms are more robust than our previous analog circuits implementing gradient-like motion algorithms. 相似文献
160.
From earwigs to humans 总被引:2,自引:0,他引:2
Rodney A. Brooks 《Robotics and Autonomous Systems》1997,20(2-4):291-304
Both direct, and evolved, behavior-based approaches to mobile robots have yielded a number of interesting demonstrations of robots that navigate, map, plan and operate in the real world. The work can best be described as attempts to emulate insect-level locomotion and navigation, with very little work on behavior-based non-trivial manipulation of the world. There have been some behavior-based attempts at exploring social interactions, but these too have been modeled after the sorts of social interactions we see in insects. But thinking how to scale from all this insect-level work to full human-level intelligence and social interactions leads to a synthesis that is very different from that imagined in traditional Artificial Intelligence and Cognitive Science. We report on work towards that goal. 相似文献