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171.
V Ritucci F Magnacca D Ipri A Russo E Leombruni N Picardi 《Canadian Metallurgical Quarterly》1996,67(5):683-6; discussion 687
INTRODUCTION: Popliteal artery aneurysms are the most common of peripheral arterial aneurysms. Popliteal aneurysms are bilateral in 42% of patients. Atherosclerosis and bacterial invasion of the arterial wall are the predominant etiologic factors of popliteal artery aneurysms. CLINICAL CASE: A male of 67 years old was referred to our institution for bilateral claudication and 150 m. free interval. The angiogram showed a partial occluded aneurysm of the right popliteal artery and a complete thrombosis of the left popliteal artery aneurysms. The left aneurysm was resected and a femoral popliteal by-pass was performed, using the inverted saphenous vein graft, associated with left lumbar sympathectomy. Six months later the contralateral aneurysm was excised and a Dacron femoro-popliteal by-pass graft was performed. Two years later Arteriographic and Doppler examination showed patent by-pass bilaterally. CONCLUSION: Popliteal artery aneurysms can be a threaten for the lower limbs, because of thromboembolic phenomena and occasional rupture. Surgery is the best treatment before the appearance of an acute complication and a by-pass with an autogenous vein graft or a Dacron graft are the most common surgical procedures performed. Thrombolytic therapy offers good results where an acute complication appears. 相似文献
172.
Aged individuals (more than 65 years) were classified as antibody (Ab) responders on the basis that they showed increases to more than or = 1:40 in serum Ab titers to all influenza virus strains present in the trivalent influenza vaccine within 4 weeks after immunization. The peripheral blood mononuclear cells (PBMC) from pre-immunization samples of blood taken from seven Ab-responders and seven Ab-nonresponders were examined for their ability to exhibit up-regulation of IgD-receptor (IgD-R) after exposure for 2 h to immobilized cross-linked IgD, as shown by rosetting with IgD-coated ox erythrocytes. The responsiveness to IgD was found to be predictive of the ability to produce Ab responses to viral protein Ag: the IgD-R up-regulation was greater than 5% in all Ab-responders and less than 4% in all the Ab-nonresponders. In addition, there was an excellent correlation between mean Ab titers (to the three viruses in sera collected 4 weeks after immunization) and the percentage of IgD-R+ cells obtained in response to IgD in PBMC from the same individual prior to immunization: p = 0.894. Injection of influenza vaccine itself also induced IgD-R on PBMC in vivo. The percentage of IgD-R+ cells peaked after 24 h, was still detectable above background by day 7 or 14, and returned to pre-injection levels by day 28 in young subjects and aged Ab-responders, but not in Ab-nonresponders. Similarly, purified peripheral blood T cells obtained from aged Ab-responders exhibited IgD-R upon immunization in vivo. These findings suggest that Ag injection causes rapid up-regulation of IgD-R by cross-linking IgD in humans as well as in mice as shown previously. In analogy with results in mice, the present data are consistent with a role for IgD-R+ T cells in the humoral response in man. Proliferative responses to influenza proteins in peripheral blood T cells from vaccinated individuals were found to peak on day 7 and were higher in Ab-responders than in Ab-nonresponders. 相似文献
173.
G. B. McFadden R. G. Rehm S. R. Coriell W. Chuck Graduate Student K. A. Morrish Graduate Student 《Metallurgical and Materials Transactions A》1984,15(12):2125-2137
During solidification of a binary alloy at constant velocity vertically upward, thermosolutal convection can occur if the
solute rejected at the crystal-melt interface decreases the density of the melt. We assume that the crystal-melt interface
remains planar and that the flow field is periodic in the horizontal direction. The time-dependent nonlinear differential
equations for fluid flow, concentration, and temperature are solved numerically in two spatial dimensions for small Prandtl
numbers and moderately large Schmidt numbers. For slow solidification velocities, the thermal field has an important stabilizing
influence: near the onset of instability the flow is confined to the vicinity of the crystal-melt interface. Further, for
slow velocities, as the concentration increases, the horizontal wavelength of the flow decreases rapidly — a phenomenon also
indicated by linear stability analysis. The lateral in-homogeneity in solute concentration due to convection is obtained from
the calculations. For a narrow range of solutal Rayleigh numbers and wavelengths, the flow is periodic in time.
Formerly with the Mathematical Analysis Division, Center for Applied Mathematics, National Bureau of Standards, Washington,
DC 20234.
This paper is based on a presentation made at the symposium “Fluid Flow at Solid-Liquid Interfaces” held at the fall meeting
of the TMS-AIME in Philadelphia, PA on October 5, 1983 under the TMS-AIME Solidification Committee. 相似文献
174.
Asserts that the dramatic changes in women's work and family roles in recent decades have profound implications for employment and family policy. It is argued that the market forces used by economists to adjust salary levels do not counteract the forces that devalue women's contributions to the economy. Depressed wages and a benefit structure based on earnings increases the likelihood of poverty of women. Many employment issues, such as the assumption that workers and family members are physically and mentally able-bodied, disabled women's employment status, and the relationships among women's physical and mental health status and work and family roles, require psychological research. The slowness of public policies to reflect women's changing roles is discussed, and tools for meeting the challenges of change, including science and technology and educational equity, are presented. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
175.
MS Brady G Perino G Tallini P Russo JM Woodruff 《Canadian Metallurgical Quarterly》1996,77(3):467-473
The human V2 vasopressin receptor belongs to the superfamily of G protein-coupled receptors believed to be anchored to the plasma membrane by seven transmembrane regions. The extracellular portion of the human V2 vasopressin receptor contains one site susceptible to N-linked glycosylation. Metabolic labeling and immunoprecipitation of the receptor expressed in transfected cells were applied to examine whether the protein was indeed glycosylated. The V2 vasopressin receptor expressed transiently was glycosylated, but glycosidase treatment to test the complexity of the sugar moiety linked to asparagine revealed that the majority of the receptor protein lacked complex carbohydrates, an indication of an improperly processed protein. This immature protein displayed a tendency to form aggregates. In contrast with these data, testing of the sugar complexity of the receptor protein synthesized in stably transfected cells identified the predominant form as an appropriately processed receptor protein. Mutagenesis of asparagine 22 to glutamine produced on expression in transfected cells a nonglycosylated receptor with ligand binding affinity and coupling characteristics almost identical to those of the wild-type form. After exposure to elevated concentrations of AVP (100 nM), the nonglycosylated form desensitized to the same extent as the wild-type receptor. 相似文献
176.
Comparison of the influence of chromium and zirconium on the quench sensitivity of Al-Zn-Mg-Cu alloys 总被引:5,自引:0,他引:5
The role played by small additions of chromium and zirconium on the “quench-sensitivity” of Al-Zn-Mg-Cu high purity alloys
has been studied. The effects of the quench rate reduction have been evaluated by mechanical testing; the associated microstructural
features have been investigated by electron microscopy. The obtained data adequately explain the mechanisms of the “quench-sensitivity”. 相似文献
177.
178.
F Ramirez JV O'Donnell PA Marks A Bank S Musumeci G Schilirò G Pizzarelli G Russo B Luppis R Gambino 《Canadian Metallurgical Quarterly》1976,263(5577):471-475
In patients with betao thalassaemia from Ferrara, beta globin mRNA sequences are either absent or structurally abnormal while in betao thalassaemia in Catania, beta globin mRNA sequences are present. In deltabeta thalassaemia there is a deletion of beta-like globin genes, while in betao Catania DNA, no beta globin gene deletion is detectable. 相似文献
179.
The proportion of zinc and copper in particles formed by laser ablation of brass was found to vary with the particle diameter. Energy-dispersive X-ray analysis showed that smaller particles were zinc enhanced while larger particles were composed mostly of copper. A model based on condensation of vapor onto large droplets ejected from a melted liquid layer is proposed to describe the change in particle composition versus size. 相似文献
180.
Hojung?ChaEmail author Jongmin?Lee Jongho?Nang Sung-Yong?Park Jin-Hwan?Jeong Chuck?Yoo Jin-Young?Choi 《Wireless Networks》2005,11(3):265-274
This paper presents a case of video streaming system for mobile phone which has actually been implemented and deployed for commercial services in CDMA2000 1X cellular phone networks. As the computing environment and the network connection of cellular phones are significantly different from the wired desktop environment, the traditional desktop streaming method is not applicable. Therefore, a new architecture is required to suit the successfully streaming in the mobile phone environment. We have developed a very lightweight video player for use in mobile phone and the related authoring tool for the player. The streaming server has carefully been designed to provide high efficiency, reliability and scalability. Based on a specifically-designed suite of streaming protocol, the server employs an adaptive rate control mechanism which transmits the media packets appropriately into the network according to the change in network bandwidth.Hojung Cha is currently a professor in computer science at Yonsei University, Seoul, Korea. His research interests include multimedia computing system, multimedia communication networks, wireless and mobile communication systems and embedded system software. He received his B.S. and M.S. in computer engineering from Seoul National University, Korea, in 1985 and 1987, respectively. He received his Ph.D. in computer science from the University of Manchester, England, in 1991.Jongmin Lee is a Ph.D. candidiate in computer science at Yonsei University, Seoul, Korea. His research interests include wireless multimedia system, QoS architecture, multimedia communication networks. He received his B.S. and M.S. in computer science from Kwangwoon University in 1999 and 2001, respectively.Jongho Nang is a professor in the Department of Computer Science at Sogang University. He received his B.S. degree from Sogang University, Korea, in 1986 and M.S. and Ph.D. degree from KAIST, in 1988 and in 1992, respectively. His research interests are in the field of multimedia systems, digital video library, and Internet technologies. He is a member of KISS, ACM, and IEEE.Sung-Yong Park is an associate professor in the Department of Computer Science at Sogang University, Seoul, Korea. He received his B.S. degree in computer science from Sogang University, and both the M.S. and Ph.D. degrees in computer science from Syracuse University. From 1987 to 1992, he worked for LG Electronics, Korea, as a research engineer. From 1998 to 1999, he was a research scientist at Telcordia Technologies (formerly Bellcore) where he developed network management software for optical switches. His research interests include high performance distributed computing and systems, operating systems, and multimedia.Jin-Hwan Jeong received the B.S. and M.S. degrees in computer science from Korea University, Seoul, Korea, in 1997, and 1999, respectively. He is currently in Ph.D. course at Korea University. His research interests include video processing for thin devices, multimedia streaming and operating systems.Chuck Yoo received the B.S. degree in electronics engineering from Seoul National University, Seoul, Korea and the M.S. and Ph.D. in computer science in University of Michigan. He worked as a researcher in Sun Microsystems Lab. from 1990 to 1995. He joined the Computer Science and Enginnering Department, Korea University, Seoul, Korea in 1995, where he is currently a professor. His research interests include high performance network, multimedia streaming, and operating systems.Jin-Young Choi received the B.S. degree from Seoul National University, Seoul, Korea, in 1982, the M.S. degree from Drexel University in 1986, and the Ph.D. degree from University of Pennsylvania, in 1993. He is currently a professor of Computer Science and Engineering Department, Korea University, Seoul, Korea. His current research interests are in real-time computing, formal methods, programming languages, process algebras, security, software engineering, and protocol engineering. 相似文献