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41.
In relation to the importance of cardiac damage in alcohol drinkers this study aims to check the modifications of some cardiac sonographic parameters in drinkers examined at different stages of alcohol intoxication. Seventy-seven male subjects (43 +/- 9 years old) were divided into 3 groups in relation to the biohumoral alterations used for the diagnosis of chronic alcoholism (increase of GGT and MGV). EF, interventricular septum hypertrophy, LVEdD and the presence of left ventricular diastolic failure were considered. All these cardiac sonographic parameters "in toto" were first compared with the same parameters of a group of normal subjects and then the differences of these sonographic parameters between the 3 groups of drinkers were evaluated. These data confirm the early onset of cardiac damage and also that the cardiac alterations may occur before the modifications of the biohumoral parameters considered too. The alterations of the cardiac sonographic parameters considered in this study seem to be a good marker for the identification, quantification and staging of cardiac damage. Interventricular septum hypertrophy, EF and EDV (in this sequence) are to be considered usefull for the diagnosis of cardiac damage in alcohol drinkers. However also LVEdD and the presence of left ventricular diastolic failure are to be evaluated before any therapy.  相似文献   
42.
Acid mine drainages (AMD) have adversely affected the southern Apuan Alps (northern Tuscany, Italy). The study particularly focuses on the Baccatoio stream, which receives AMD from the abandoned Pollone and M. Arsiccio mines. The mine waters have an average pH of 2.2 and contain potentially toxic elements (PTE) at concentrations that exceed the Italian regulatory threshold for Al, Fe, Mn, Cu, Zn, As, Ni, Co, Cd, Sb, Pb, and Tl. The AMD flow directly into the stream, severely contaminating it. Downstream of the mined areas, the pH increases and most PTE (especially Fe, Al, As, and Pb) are readily scavenged from the stream waters by precipitation and/or adsorption. However, Tl, which peak at 1000 µg/L in the AMD, behaves almost conservatively along the stream flow path, undergoing only dilution, and remains at or above the concentration of concern of 4 µg/L almost to the coastline, before sharply decreasing to 0.5 µg/L where seawater is encountered. Since the stream water was locally used for irrigation, these observations may have important environmental and public health consequences in such a densely populated area.  相似文献   
43.
The effect of elevated ripening temperature on physicochemical, biochemical and sensory characteristics in Reggianito Argentino cheese was evaluated to determine the optimal time for cheese ripening at 18 °C that ensures typical cheese characteristics. Cheeses ripened at 12 or 18 °C and 85% relative humidity were analysed at 2, 4 and 6 months. Seventy-eight variables (as determined by urea-PAGE, RP-HPLC of the water-soluble at pH 4.6 fraction, free amino acids, free fatty acids and sensory analysis) were considered for the principal component analysis. The statistical analysis allowed determination of the optimal time for ripening Reggianito Argentino cheese at 18 °C, which was ranged between 2 and 3 months. In conclusion, the results obtained were not only useful in characterising the ripening of an Argentinean hard cheese, but also in evaluating the effect of an increase of ripening temperature on the main physicochemical, biochemical and sensory changes of Reggianito Argentino cheese.  相似文献   
44.
Integration of stereo and motion information was measured on the basis of observers' ability to discriminate between triangle- and sine-wave corrugated surfaces or sinusoidal surfaces of different spatial frequency. Discrimination performance for the triangle-sine task was consistent with independent processing of motion and stereo, but the spatial frequency discrimination task led to performance superior to that predicted by an independent combination of motion and stereo signals, indicating that the integration of stereo and motion depends on the type of 3-dimensional structure observers are required to discriminate. This pattern of results is consistent with the existence of multiple stereoscopic mechanisms suggested by psychophysical and neurophysiological data.  相似文献   
45.
A series of approximately 100 laboratory images have been made with the ZEBRA astronomical telescope using a range of radioactive sources. These images were aimed at assessing the performance of the telescope and included combinations of point sources, extended sources, ring sources as well as vignetted sources. Besides linear reconstruction techniques a range of non linear image restoration processes are discussed.  相似文献   
46.
The differential diagnosis of recurrent hepatitis C following orthotopic liver transplantation (OLT) may be difficult. We evaluated the diagnostic significance of IgM anti-hepatitis C virus (anti-HCV) core antibodies in 27 patients undergoing OLT because of HCV-associated cirrhosis. Serial serum samples collected before and after OLT were tested for the presence of IgM anti-HCV core antibodies. Results were compared with the histological evidence of liver damage, the presence, level, and genotype of serum HCV RNA and the degree of immunosuppression. All patients underwent recurrent HCV infection. Recurrent hepatitis was diagnosed histologically in 21 patients an average of 48 weeks after OLT (range 2-209 weeks): 18 had persistence or (re-)appearance of the IgM anti-HCV core after OLT, one lost the IgM anti-HCV core after OLT, and two never secreted IgM anti-HCV core either before or after OLT. The remaining six patients did not develop recurrent hepatitis after a follow-up of 44-241 weeks from OLT; in these patients, IgM anti-HCV core either disappeared (1 case) or decreased (1 case) after OLT or were persistently negative throughout the study (4 cases). Thus, 18/21 patients with recurrent hepatitis, but only one of six without recurrent hepatitis, secreted IgM anti-HCV core after OLT (P < 0.05). The IgM anti-HCV core levels were not correlated with the level or genotype of serum HCV RNA or the degree of immunosuppression. In conclusion, secretion of IgM anti-HCV core antibodies after OLT seems associated with recurrence of HCV-associated liver disease and may have diagnostic significance.  相似文献   
47.
Reggianito is a typical variety of grana-type hard cheese produced in Argentina. It is the most exported and due to its organoleptic characteristics is very appreciated by the consumers. The objective of this study was to characterise the global composition, lipolysis, proteolysis and volatile compound profiles of commercial Reggianito cheeses from different dairy plants.Statistical differences (P ? 0.05) in some physicochemical parameters, nitrogen fractions and FFA levels among commercial brands were detected. The volatile profiles were studied by SPME–GC–MS/FID. A total of 53 compounds were identified, the majority belonging to the groups of ketones, alcohols, acids, esters and aldehydes. All these compounds have been reported in Italian grana-type cheeses. Visualization of the analytical results was performed by principal component analysis. This analysis clustered cheese samples according to dairy plants. This fact could be, among other factors, consequences of differences in technologies and ripening time of different manufacturers.  相似文献   
48.
介绍了达涅利实时在线带卷质量预测评估(DANIELI-CQEOnline)系统模型组件。运用该系统针对低碳钢、高碳钢、高强度低合金钢进行了大量的力学性能预测评估,系统输出数值与实际检验结果进行了对比,结果显示预测评估数值与实验结果相当吻合。  相似文献   
49.
We investigated the presence of enzymes on the surface of Drosophila melanogaster spermatozoa that might bind the carbohydrate residues of the egg shell. Spectrophotometric and fluorimetric studies were used on whole spermatozoa to assay galactosyltransferase and glycosidase activities. No galactosyltransferase is present on the sperm surface, whereas two glycosidases, beta-N-acetylglucosaminidase (GlcNAc'ase) and alpha-mannosidase (Man'ase), have been evidenced. They have an optimal pH of 6-6.5 and 4, respectively. The same glycosidases were detected as soluble forms probably secreted by the seminal vesicle epithelium. We suggest that these enzymes might be involved in the recognition of alpha-mannose and beta-N-acetylglucosamine residues present on the egg shell at the site of sperm entry.  相似文献   
50.
A set of 4 experiments evaluated observers' sensitivity to three-dimensional (3-D) length, using both discrimination and adjustment paradigms with computer-generated optical patterns and real objects viewed directly in a natural environment. Although observers were highly sensitive to small differences in two-dimensional length for line segments presented in the frontoparallel plane, their discrimination thresholds increased by an order of magnitude when the line segments were presented at random orientations in 3-D space. There were also large failures of constancy, such that the perception of 3-D length varied systematically with viewing distance, even under full-cue conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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