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101.
G Pons-Lladó F Carreras X Borrás J Palmer J Llauger A Bayés de Luna 《Canadian Metallurgical Quarterly》1997,79(12):1651-1656
To compare the value of echocardiography and magnetic resonance imaging (MRI) in the assessment of the amount and extent of hypertrophy in hypertrophic cardiomyopathy (HC) and, second, to correlate the degree of hypertrophy, as assessed by MRI, with clinical and electrocardiographic parameters, 30 consecutive patients (16 men and 14 women, aged 20 to 74 years) with HC were studied. Measurements of left ventricular wall thickness were performed at 11 predetermined segments (5 basal, 5 midventricular, and 1 apical) by 2-dimensional echocardiography and MRI. Two parameters derived from MRI studies were considered as indicators of the degree and extent of hypertrophy: (1) mean of the measured wall thickness at the 11 segments, and (2) the number of segments with thickness > 15 mm. Results showed that, from a total of 330 myocardial segments, thickness could be measured by echocardiography in 221 (67%), whereas MRI allowed measurement of 320 segments (97%). When compared with clinical and electrocardiographic data, no correlation was found regarding mean wall thickness and number of hypertrophied segments by MRI except for the presence of an abnormal electrocardiographic repolarization pattern. It is concluded that MRI allows a better assessment of the degree and extension of left ventricular hypertrophy than echocardiography in HC. Despite the precise information on hypertrophy provided by MRI, the amount and degree of hypertrophy bears no correlation with most of the clinical data in these patients. 相似文献
102.
103.
JJ Bourguignon L Désaubry P Raboisson CG Wermuth C Lugnier 《Canadian Metallurgical Quarterly》1997,40(12):1768-1770
A 6-year-old Quarter Horse gelding with acute onset of a grade-4/5 lameness of the left forelimb 21 days after an encounter with a porcupine was examined. Quills had been removed by the referring veterinarian, and the horse had been treated with antibiotics and hydrotherapy for 14 days. The horse was pyretic and had effusion in the digital synovial sheath. Signs of pain were elicited on palpation of the area. A tentative diagnosis of septic tenosynovitis caused by a porcupine quill was made. Exploratory tenoscopy revealed large amounts of fibrin in the sheath and a 1.2-cm quill. Bacteriologic culture of synovial fluid yielded a pure growth of Staphylococcus aureus. The horse improved dramatically after tenoscopic removal of the quill, debridement of fibrin, and lavage to dilute inflammatory mediators and bacteria, debridement of fibrin, discovery and removal of a quill, and complete evaluation of the sheath for prognostic purposes. Tenoscopy can provide a means for direct observation and enhance the ability of clinicians to debride a septic synovial sheath in a minimally invasive manner. 相似文献
104.
105.
Pb1–x
Ca
x
[(Co0.5W0.5)0·05Ti0.95]O3 ceramics with x = 0.24, 0.30 and 0.35, are prepared by a solid state reaction of oxides. Deviations from nominal chemical compositions and formation of segregated phases different from modified lead titanate perovskites, are studied. Pyro- and non-pyroelectric currents excited in the material by a thermal wave are investigated and related to mobility of electrical charges in the materials. 相似文献
106.
M. Lamirand J. -L. Bonnentien S. Guérin G. Ferrière J. -P. Chevalier 《Metallurgical and Materials Transactions A》2006,37(8):2369-2378
The effect of added oxygen in the range of 1000 to 4000 wt ppm on the microstructures of a Ti-48Al-2Cr-2Nb alloy has been
investigated and compared to the microstructures for a high-purity alloy. For specimens cooled from theα phase, interstitial oxygen stabilizes the lamellar microstructure with respect toγ grains, with higher than equilibrium values for theα
2 volume fraction. For specimens cooled from theα +γ phase field, the lamellar microstructure still tends to be favored by oxygen, but it is found that the phase volume fractions
are not significantly different from equilibrium values. This suggests that interstitial O essentially reduces the kinetics
of theα toα +γ transformation. Thus, interstitial oxygen will have a strong effect on microstructures obtained by continuous cooling fromα, but significantly less on those, such as the duplex microstructure, obtained by long treatment in theα +γ phase field. In general, increased O content is well correlated with reduced ductility. Finally, the role of interstitial
oxygen on this phase transformation is discussed. 相似文献
107.
C. R. Hutchinson H. S. Zurob Y. Bréchet 《Metallurgical and Materials Transactions A》2006,37(6):1711-1720
The growth of allotriomorphic ferrite from austenite in Fe-C-X alloys is studied. Two systems have been selected: the Fe-C-Ni
system, in which the substitutional alloying element is expected to have a weak interaction with both the C and the moving
interface, and the Fe-C-Mo system, in which these interactions are expected to be non-negligible. The ferrite growth kinetics
was measured using two types of experiments: classical isothermal heat treatments and decarburization experiments. All of
the experimental observations can be quantitatively rationalized using a model that describes an evolution in interfacial
conditions from paraequilibrium (PE) to local equilibrium with negligible partitioning (LENP) during growth.
This article is based on a presentation made in the “Hillert Symposium on Thermodynamics & Kinetics of Migrating Interfaces
in Steels and Other Complex Alloys,” December 2–3, 2004, organized by the The Royal Institute of Technology in Stockholm,
Sweden. 相似文献
108.
The possibility of long-term safe disposal of radioactive wastes based on their radiation and radiation-migration balance with the initial fuel component and taking account of the thermal, radiation, and elastic loads due to waste dispoasl on the natural medium is examined. The specific radiation and radiation-migration equivalence is established on the basis of the radiotoxicity of uranium and the components of the decay of uranium and individual radionuclides as well as the sum of the latter. 相似文献
109.
Electron Spin Resonance, Differential Scanning Calorimetry and rheological techniques have been used to study the physical
changes induced by temperature in lard and in the solid and liquid fractions obtained by fractionation of lard at 15 C. The
mobilization process of a C18 fatty acid nitroxide derivative dispersed in the molten fat has been observed in the temperature
range −50 to +70 C.
The mobilization of the probe seemed to be concomitant with the melting of the low melting point glycerides. Above this temperature,
all the probes were in the liquid phase and their mobility reflected the viscosity of their liquid environment, or the viscosity
of the bulk fat when crystal was no longer present.
Probe mobility was temperature dependent, and it was identical for the three fats at the same temperature, despite their different
triglyceride compositions. 相似文献
110.
Phillips Dorothy A.; Hearty Paul J.; Latrémouille Susane; Treurniet William C.; Whalen Thomas E. 《Canadian Metallurgical Quarterly》1985,26(3):219
Discusses telematics, a new field of behavioral research in Canada that has grown with the technical developments in which computers and telecommunications have been combined. Three domains of behavioral research reflect relationships between humans and the technology and use the evidence and methods of different areas of psychology: (1) interface studies address perception and performance questions, (2) dialog studies focus on cognitive processes, and (3) impact studies investigate social relations and how institutions and individuals are affected by telematics. Studies conducted during the past 5 yrs by the Behavioural Research and Evaluation division of the Department of Communications, Government of Canada, are described in each of these 3 domains. Behavioral research in telematics is expected to be an increasingly important activity in which psychologists may play an active part as the technology disseminates. (French abstract) (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献