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71.
PR Moreno JT Fallon VH Bernardi L Harrell NJ Weissman V Fuster A Rodríguez IF Palacios 《Canadian Metallurgical Quarterly》1998,136(5):804-811
BACKGROUND: Early loss of minimal luminal diameter of >0.3 mm after successful percutaneous transluminal coronary angioplasty (PTCA) is associated with a higher incidence of restenosis. The underlying mechanism of this early loss is unknown and thrombus may be a contributing factor. METHODS: We performed a prospective study using quantitative computerized planimetry on coronary tissue specimens obtained by directional coronary atherectomy of 24 lesions in which early loss occurred 22+/-9 minutes after successful PTCA. RESULTS: Thrombus was present in 9 (37%) of 24 coronary specimens. Segmental areas (mm2) and percentage of total area were distributed as follows: sclerotic tissue, 4.07+/-0.7 mm2 (63%+/-6%); fibrocellular tissue, 0.97+/-0.27 mm2 (16%+/-4%); hypercellular tissue, 0.99+/-0.29 mm2 (12%+/-3%); atheromatous gruel, 0.18+/-0.07 mm2 (3%+/-0.1%); and thrombus, 0.24+/-0.15 mm2 (6%+/-0.4%). There was no difference in the relative early loss index between lesions with or without thrombus (35%+/-7% vs 26%+/-2%, respectively; P= .87). Multiple stepwise regression analysis did not identify any histologic predictors of relative early loss index. CONCLUSION: Histopathologic analysis of coronary lesions with early loss after successful PTCA suggests that thrombus may not play a significant role in this angiographic phenomenon. 相似文献
72.
D Elias A Cavalcanti P Dubé M Julieron G Mamelle J Kac M Ducreux S Bonvallot G Nitenberg P Lasser 《Canadian Metallurgical Quarterly》1998,5(6):511-516
In 1996, 20 of 21 patients with mucosal leishmaniasis, treated in 1994 with aminosidine sulfate, 16mg/kg/day salt, by intramuscular injection for 20 days, were clinically evaluated. One patient died due to disease not related to mucosal leishmaniasis. Seven of 14 patients (66.7% N = 21) who achieved complete remission three months after treatment remained clinically cured 24 months later and seven relapsed in the same period (50% N = 14). Sorological follow-up showed poor correlation with the results of clinical examination. 相似文献
73.
Elias C. Aifantis 《International Journal of Engineering Science》1980,18(6):857-867
The problem of flow in media with double porosity (e.g. fissured rocks) is considered by utilizing the author's concept of “multiporosity” and employing the apparatus of continuum theory of mixtures. Relevant results obtained by Barenblatt et al. within the Russian literature are shown to be contained in the present theory. 相似文献
74.
E. Elias 《Nuclear Engineering and Design》1981,64(2):249-257
A theoretical model is developed which allows a consistent treatment of the wall heat flux in an inverted-annular film boiling regime. The model is based on an analytical solution of the energy conservation equations in the vapor and liquid regions downstream of the quench front. A constant vapor film thickness is assumed, which depends on the fluid equilibrium quality at the quench front. Good agreement is obtained in comparing the model with quasi-steady state experimental results. 相似文献
75.
76.
Iucci G Infante G Rossi L Polzonetti G Rosato N Avigliano L Savini I Catani MV Palacios AC 《Journal of materials science. Materials in medicine》2004,15(5):601-606
Glasses incorporating increasing amounts of bovine serum albumin were prepared by sol-gel techniques from a tetra methoxy silane precursor. The surface of the glass samples was studied by X-ray photoelectron spectroscopy, revealing that the protein is present also in the superficial layer of the silica network. Moreover, the protein is distributed in a dose-dependent way, since the N/Si atomic ratio increases linearly with the albumin concentration in the reaction mixture. Angle-dependent measurements show that the protein distribution occurs homogeneously and is the same at different sampling depths. Protein incorporation in the bulk SiO2 network, with a uniform protein distribution between bulk and surface, is confirmed by infrared spectroscopy measurements, performed both in reflectance and transmittance mode. The reaction with a specific antibody and the adhesivity assay of osteoblastic cells show that embedded albumin present on the glass surface is able to interact with other proteins. 相似文献
77.
SEM and X-ray microprobe analysis were combined with clean lab technology atomic absorption spectroscopy to observe the deposition of aerosols on undisturbed pine needle surfaces, to obtain physical and chemical information from the observed particles and to chemically remove these particles for analysis. Comparisons were made among sites with traffic densities of 100, 1000, 10000 cars per day. Correlations were made with periods of heavy rainfall. The results show that the particle size distribution, shape and surface chemistry are possibly characteristic of automotive exhausts, that both the chemical washing procedure and rainfall efficiently remove most particles from the surface, including those bearing lead, and that the rate of deposition is constant between rainfalls and partly a function of traffic density. Deposition rates of 0.3 ng Pb cm?2 day?1 were observed at 100 cars per day, 2–3 ng Pb cm?2 day?1 for 1000 and 10000 cars per day. 相似文献
78.
This article gives a robust estimator of the trend parameters in multivariate spatial linear models. This estimator is presented
as an alternative to the classical one which is obtained by using cokriging. The goal focuses on improving predictions of
spatial variables when data contain both atypical and high influence observations. The procedure consists of extending robust
methods used in linear regression models to the multivariate spatial context. The resulting estimator belongs to the class
of GM-estimators and then, it is a bounded influence estimator and it has good robust properties, in particular, a high breakdown
point and a high efficiency. An illustrative example is given to show how the proposed estimator works.
Research partially supported by Ministerio de Ciencia y Tecnología, Project AGL2000-0978. 相似文献
79.
J. Elias 《Thin solid films》2007,515(24):8553-8557
The role of a ZnO buffer layer on the electrodeposition of ZnO nanowire arrays was analyzed. ZnO buffer layers were deposited on conducting glass substrates by spray pyrolysis and electrodeposition. The electrodeposited ZnO buffer layer resulted in a collection of open-packed small grains (∼ 20 nm), while the sprayed layers were comprised of close-packed grains with size in the range of 15-100 nm. The ZnO nanowire arrays electrodeposited on ZnO buffer layers exhibited increased nanowire density (by factors of 6× and 3×, for electrodeposited and sprayed buffer layers, respectively) compared to arrays deposited directly on naked substrates, demonstrating that ZnO nanocrystalline layers can be used to increase nucleation sites for nanowire growth. On the other hand, nanowire diameters were tailored from 45 to 160 nm as a function of the size of the grains in the buffer layer. The influence of crystallographic orientation of the buffer layer was also analyzed. 相似文献
80.
The society of telecommunication and computer networks encompasses a wide variety of organizations, forums and industry companies
that specify, standardize, evaluate, implement and deploy network infrastructures. These infrastructures are well defined
and deployed in order to offer high quality end-user services and meet the need for interconnectivity, expandability and upgradeability.
What users see and experience is the tip of the iceberg. Great amount of time and money is spent in specification, standardization,
design, debugging, testing (both conformance and stress) and finally evaluating network components or subsystems before the
deployment takes place. The framework, proposed in the current paper and implemented in open source software library, provides
an object oriented methodology for the implementation of network protocols and the software realization of network components.
The method is formed in respect to: (a) operating system architecture (b) network architecture and (c) Object Oriented (OO)
methodology. 相似文献