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991.
GF Anderson 《Canadian Metallurgical Quarterly》1997,16(6):163-171
The United States spent the most resources on health care of all the twenty-nine industrialized countries in 1996 by a wide margin. Managed care and other recent initiatives have been credited with slowing the rate of increase in the U.S. health care spending in recent years. Although the rate of increase slowed, it was still more rapid than the rate in most other industrialized countries between 1990 and 1996. Among the twenty-nine industrialized countries, the United states had the lowest percentage of its population eligible for publicly mandated insurance in 1995. Since 1960 Greece, Korea, and Mexico have surpassed the United States on this measure. AMong the twenty-nine industrialized countries, only the United States had less than half of its population eligible for publicly mandated health insurance in 1995. The United States appears to be comparable to the other G7 countries in terms of access to physicians, in-patient hospital services, and pharmaceuticals. However, on outcomes indicators such as life expectancy and infant mortality, the United States is frequently in the bottom quartile among the twenty-nine industrialized countries, and its relative ranking has been declining since 1960. 相似文献
992.
Blind Equalization and Carrier Recovery Using a "Stop-and-Go" Decision-Directed Algorithm 总被引:2,自引:0,他引:2
We show that the standard decision-directed estimatedgradient adaptation algorithm for joint MSE equalization and carrier recovery, normally utilized in the open-eye condition, can be turned into an algorithm providing effective blind convergence in the MSE sense, usable in the closed-eye startup phase with no need of a known training sequence. This is obtained by means of a simple flag telling both the equalizer and the synchronizer whether the current output error with respect to the decided symbol is sufficiently reliable to be used. If not, adaptation is stopped for the current iteration. In the paper, this "stopand-go" decision-directed algorithm is presented for both linear and decision-feedback MSE complex equalizers with joint blind carrier recovery. Simulation results demonstrate the effectiveness of the proposed technique. 相似文献
993.
994.
M Joyeux GF Baxter DL Thomas C Ribuot DM Yellon 《Canadian Metallurgical Quarterly》1997,29(12):3311-3319
Heat stress (HS) is known to protect against mechanical dysfunction and myocardial necrosis in myocardial ischemia-reperfusion models both in vivo and in vitro. However, the mechanisms involved in this form of cardioprotection remain unclear. Protein kinase C (PKC) and tyrosine kinase activation have both been shown to be involved in the delayed phase of protection following ischemic preconditioning, a phenomenon which appears to be analogous to HS-induced protection. Therefore, we investigated the role of PKC and tyrosine kinase in HS-induced resistance to myocardial infarction, in the isolated rat heart. The selective inhibitors chelerythrine (Che) and genistein (Gen) were used to inhibit PKC and tyrosine kinase, respectively. Rats were treated with Che (5 mg/kg, i.p.) or Gen (5 mg/kg, i.p.) or vehicle before they were either heat stressed (42 degrees C for 15 min) or sham anesthetized. Twenty-four h later their hearts were isolated, retrogradely perfused, and subjected to 35-min occlusion of the left coronary artery followed by 120-min of reperfusion. Infarct-to-risk ratio was significantly reduced in HS (19.9+/-1.1%) compared to sham (43.1+/-1.1%) hearts. This reduction in infarct size was abolished in chelerythrine-treated groups (43.8+/-1.9% in HS+Che v 44.9+/-2.0% in sham+Che), but was conserved in genistein-treated groups (17.7+/-0.9% in HS+Gen v 36.4+/-2.8% in sham+Gen). In order to confirm that genistein at this dose was effectively inhibiting tyrosine kinase activity, we observed the ability of the agent to prevent the hypoglycemic responses to insulin in a separate group of anesthetised rats receiving an i.v. insulin infusion. Western blot analysis of the myocardial hsp72 showed a HS-induced increase of this protein, which was modified by neither the PKC inhibitor, chelerythrine, nor the tyrosine kinase inhibitor, genistein. We conclude that the activation of PKC, but not of tyrosine kinase, appears to play a role in the functional cardioprotection associated with the heat stress response. Although protection appears to be dissociated from induction of hsp72, further work is required to explore the importance of hsp72 phosphorylation to cytoprotective activity of the protein. 相似文献
995.
P Iannetti U Raucci LA Basile A Spalice C Di Biasi G Trasimeni GF Gualdi 《Canadian Metallurgical Quarterly》1993,82(5):501-503
We report a 10-year-old girl who presented with a single episode of partial complex seizure. Neurological examination and psychological evaluation were normal. Electroencephalogram showed abnormalities in the left temporo-occipital region. Magnetic resonance imaging revealed a bilateral layer of tissue iso-intense with gray matter, between the wall of the lateral ventricle and the cortex, extending from the frontal to the occipital region, and enlarged left lateral ventricle. The images indicated diffuse cortical dysplasia, also known as band heterotopia or "double cortex", and left cortical hemiatrophy. 相似文献
996.
Use of citiolone in chronic hepatitides. Results of a research with clinical and laboratory controls
F Miglio A D'Ambro GF Stefanini GR Corazza O Pesa L Flacco C Schiavone G Gasbarrini 《Canadian Metallurgical Quarterly》1977,68(46):3177-3192
The therapeutic possibilities offered by the use of a new substance, 3-acetamido-2-oxo-tetrahydro-thiophene or citiolone, in two groups of patients, the first suffering from persistent chronic hepatitis, the second from aggressive chronic hepatitis and-or compensated cirrhosis diagnosed on the basis of clinical, laboratory, and bioptic findings have been studied. The experiment was of "between patients" pattern and findings were obtained with the double-blind method. Tests were compared with a placebo and all patients were treated with a basic therapy consisting of a polyvitaminic complex. In both groups, the results confirmed the therapeutic effectiveness of the new substance and this was demonstrable, including statistically, in an improvement in the clinical picture and, above all, in certain liver function exploration tests. At termination of the treatment cycle, liver biopsies were carried out in certain patients and these showed an improvement in the liver cell picture. 相似文献
997.
The pia mater of the human brain hemispheres has liquor canals which form a continuous network communicating with the cisterns of the brain base. The wall of the liquor canals is formed by a fibro-collagenous framework covered from two sides with the arachnoidendothelium. In the canal walls there are openings, through which the lumens of the canals communicate with the lumens of alveoli. The liquor canals are divided into the circulatory and excretory ones. The circulatory canals are disposed in the depth of the cerebral sulci, the secretory canals--on the surface of the convolutions. The liquor moves along the circulatory canals from the cisterns of the brain base onto the surface of cerebral hemispheres. Excretory canals adjoin the arachnoid membrane which is part of its wall (the "roof"). In the "roof" of the liquor canals the fibrocollagenous basis and the number of layers of the arachnoid--endothelium are reduced, the intercellular spaces between the cells of the arachnoidendothelium are dilated. Through the roofs of the liquor canals the liquor is excreted from the subarachnoid space into the subdural space. Inside the liquor canals there are arteries of the pia mater hung up to the canal walls by trabeculae (cords) of a dense connective tissue. 相似文献
998.
Methods for the measurement of calcium in the diet, urine and faeces for the performance of a calcium balance study was described, along with experiments on analytical procedures including recovery values. A means of calculating the inherent "technical error" in such a balance is given, and a method for determining the significance of any change in a patient's balance is described. These are illustrated by worked examples of data from a patient suffering from Paget's disease and one with osteoporosis before and after treatment with calcitonin. 相似文献
999.
Several papers addressed ellipse detection as a first step for several computer vision applications, but most of the proposed solutions are too slow to be applied in real time on large images or with limited hardware resources. This paper presents a novel algorithm for fast and effective ellipse detection and demonstrates its superior speed performance on large and challenging datasets. The proposed algorithm relies on an innovative selection strategy of arcs which are candidate to form ellipses and on the use of Hough transform to estimate parameters in a decomposed space. The final aim of this solution is to represent a building block for new generation of smart-phone applications which need fast and accurate ellipse detection also with limited computational resources. 相似文献
1000.
Poly(ethylene terephthalate) films having different morphologies have been coloured with some azo dyes. Isotropic and anisotropic films showed an inversion in dyeing behaviour as well as in light fastness, always at crystallinity β=0.5. We have interpreted the phenomenon in terms of a different localisation of the dye in going from a structure of PET corresponding to a free-volume model to a structure corresponding to a pore model. It was found that polymer morphology strongly affected dye photofading whilst the thermal cis-trans isomerisation of azo dyes in the PET matrix depended only on the amorphous region; below the glass transition temperature isomerisation proceeded in a way that was determined by the effects of restrictions in the mobility of the photochrome itself. 相似文献