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PURPOSE--To analyze the influence of transient and sustained elevations of arterial pressure (AP) on the rate of rise of the left ventricular pressure (dp/dt). METHODS--Thirteen anesthetized, thoracotomized and mechanically ventilated dogs, submitted to pharmacological autonomic block (oxprenolol-3 mg/kg plus atropine-0.5 mg/kg). The AP elevation was obtained by mechanical constriction of the descending thoracic aorta. Two protocols were applied to all animals: Transient Arterial Hypertension (TAH) and Sustained Arterial Hypertension (SAH) and the following variables were evaluated: heart rate (HR), systolic (LVSP) and end diastolic (LVEDP) left ventricular pressure and dp/dt. In TAH the variables were analyzed in the basal condition (To) and at the maximal value of AP attained during the transient pressure elevation (TM). In the protocol SAH the variables were evaluated in the conditions: Control (Ho), hypertension 1 (H1) and hypertension 2 (H2). RESULTS--Considering all conditions, there were no significant differences among the values of HR. In the protocol TAH, the LVSP varied from 133 +/- 22 mmHg to 180 +/- 27 mmHg, whereas in SAH the values of LVSP were as follow: HO = 129 +/- 25 mmHg; H1 = 152 = 23 mmHg; H2 = 182 +/- 24 mmHg. LVEDP changed in both protocols: To = 7 +/- 2 mmHg; TM = 13 +/- 2 mmHg (p < 0.05); Ho = 7 +/- 2 mmHg; H1 = 10 +/- 2 mmHg; H2 = 14 +/- 3 mmHg (p < 0.05). During TAH there was no difference between the values of dp/dt (To = 3.303 +/- 598 mmHg/s; TM = 3.350 +/- 653 mmHg/s; p > 0.05), however, there were increases of the dp/dt during SAH (Ho = 3.233 +/- 576 mmHg/s; H1 = 3.831 +/- 667 mmHg/s; H1 = 4.594 +/- 833 mmHg/2; p < 0.05). CONCLUSION--The values of dp/dt are not influenced by transient elevation of AP. Sustained increase of AP activates cardiac adjustments, which results in elevation of dp/dt, by stimulation of contractile state. Probably, the inotropic intervention mechanism is the length dependent activation due to the Frank-Starling mechanism.

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Sodium (Na+) and chloride (Cl-) nutritional requirements, dietary electrolyte balance (DEB), and their effects on acid-base balance, litter moisture, and tibial dyschondroplasia (TD) incidence for young broiler chickens were evaluated in two trials. One-day-old Cobb broilers were distributed in a completely randomized design with six treatments, five replicates, and 50 birds per experimental unit. Treatments used in both experiments were a basal diet with 0.10% Na+ (Experiment 1) or Cl- (Experiment 2) supplemented to result in diets with Na+ or Cl- levels of 0.10, 0.15, 0.20, 0.25 ,0.30, or 0.35%, respectively. In Experiment 1, results indicated an optimum Na+ requirement of 0.26%. Sodium levels caused a linear increase in arterial blood gas parameters, indicating an alkalogenic effect of Na+. The hypertrophic area of growth plate in the proximal tibiotarsi decreased with Na+ levels. The TD incidence decreased with increases in dietary Na+. Litter moisture increased linearly with sodium levels. In Experiment 2, the Cl- requirement was estimated as 0.25%. Chloride levels caused a quadratic effect (P ≤ 0.01) on blood gas parameters, with an estimated equilibrium [blood base excess (BE) = 0] at 0.30% of dietary CT-. No Cl- treatment effects (P ≥ 0.05) were observed on litter moisture or TD incidence. The best DEB for maximum performance was 298 to 315 mEq/kg in Experiment 1 and 246 to 264 mEq/kg in Experiment 2. We concluded that the Na+ and Cl- requirements for optimum performance of young broiler chickens were 0.28 and 0.25%, respectively.

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We report Pelecitus helicinus Railliet & Henry, 1910 from 13 species of birds of 2 orders and 7 families, collected from the states of São Paulo and Mato Grosso, Brazil. All 13 constitute new host records for this nematode. In addition, we report the first record of Aprocta golvani Diaz-Ungria, 1963 from Brazil and Monasa nigrifrons (Bucconidae), as well as a number of other nematode records from Neotropical birds.

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We propose a natural extension of the BRST-antiBRST superfield covariant scheme in general coordinates. Thus, the coordinate dependence of the basic tensor fields and scalar density of the formalism is extended from the base supermanifold to the complete set of superfield variables. © Springer-Verlag.

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Leptospirosis was seroepidemiologically investigated in 775 dogs from Botucatu, state of Sao Paulo, in blood samples collected during the annual anti-rabies vaccination campaign. The samples were collected from 14 out of the 45 vaccination stations geographically distributed in five different municipal districts, with a territorial urban area of 31Km2. Samples were taken from 449 males and 326 females; 564 were of undetermined breed, and 211 were pedigree animals; ages ranged from 3 months to 20 years. Diagnosis included the microscopic serum agglutination tests using 12 Leptospira spp serovars. Serological results and epidemiological variables were compared using Goodman and chi-square tests, with χ=0.05. There were 119 (15.3%) positive samples for 11 serovars; the most important was canicola with 48 (40.3%), followed by pyrogenes 41 (34.5%). Statistical analysis showed significant difference for: breed, 17.7% positive in undetermined breeds and 9.0% in pedigrees; and sex, 18.4% positive in males and 11.0% in females. There was no statistically significant difference in relation to age with uniform distribution of positives.

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Introduction. Complex relations between brain and psychopathology have attracted the interest of researchers, aiming to clarify the neurobiological mechanisms of depression in Parkinson's disease, obviously in addiction to mental features. Aims. The association of motor impairment and decline of personal autonomy with severity of depressive symptoms was the hypothesis of the present study. Aiming to check this hypothesis, the objective of this study consisted in investigating relationships between the severity of depressive symptoms and motor characteristics of Parkinson's disease. Patients and methods. Thirty patients (53 to 80 year-old) with medical diagnosis of idiopathic Parkinson's disease in initial clinic stages were studied. The Unified Parkinson's Disease Rating Scale, Hoehn-Yahr Scale, and Schwab & England Scale were used to assess the clinic signs and symptoms. The depressive symptoms were identified by complete anamnesis, examination of mental condition, and the Hamilton Rating Scale for Depression and the Anxiety and Depression Scale. Statistical analysis was performed by Pearson's correlation and multiple regression analysis. Results. A significant correlation of severity of depression symptoms with disease stage (p < 0.02), with motor signs (p < 0.008), and with functional performance (p < 0.007) was found. Conclusion. There was significant association between motor impairment and severity of depressive symptoms, and between depression and early disease onset or prolonged duration of Parkinson's disease. © 2007, Revista de Neurología.

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During gray cast iron cutting, the great rate of mechanical energy from cutting forces is converted into heat. Considerable heat is generated, principally in three areas: the shear zone, rake face and at the clearance side of the cutting edge. Excessive heat will cause undesirable high temperature in the tool which leads to softening of the tool and its accelerated wear and breakage. Nowadays the advanced ceramics are widely used in cutting tools. In this paper a composition special of Si3N4 was sintering, characterized, cut and ground to make SNGN120408 and applyed in machining gray cast iron with hardness equal 205 HB in dry cutting conditions by using digital controlled computer lathe. The tool performance was analysed in function of cutting forces, flank wear, temperature and roughness. Therefore metal removing process is carried out for three different cutting speeds (300 m/min, 600 m/min, and 800 m/min), while a cutting depth of 1 mm and a feed rate of 0.33 mm/rev are kept constant. As a result of the experiments, the lowest main cutting force, which depends on cutting speed, is obtained as 264 N at 600 m/min while the highest main cutting force is recorded as 294 N at 300 m/min.

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Data on the reproductive and feeding biology of elasmobranchs from Manoel Luís Reefs, Maranhão State, Brazil. Nine species were recorded and evidences that the area is important for the reproduction and feeding activity of sharks and rays were obtained.

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Abstract. Background: The high blood lipid levels and obesity are one of the main risk factors for cardiovascular diseases, and the atherosclerotic process begins in childhood. Some environmental factors are supposed to be involved in this relationship, such as dietary factors. This study aimed to investigate the relationship between dietary intake and blood lipids levels in overweight and obese schoolchildren. Methods. This is a cross-sectional study with 147 overweight and obese schoolchildren in Botucatu city, Brazil. The anthropometric measurements (body weight, height, body mass index, waist circumference and skinfolds), pubertal staging evaluation and biochemical tests were taken in all children. Three 24h-recall were applied in order to estimate the dietary intake and its relationship with blood lipid levels. The Student t test and multiple linear regression analysis were used for statistical analysis. Statistical significance was assessed at the level of 0.05. The data were processed in SAS software (version 9.1.3; SAS Institute). Results: At this study, 63% of children were obese (body mass index higher than 95§ssup§th§esup§ percentile) and 80% showed high body fat percentage. The percentage of children with abnormal total cholesterol and triglycerides was 12% and 10%, respectively, and 28% presented at least one abnormal lipid levels. The average values of anthropometric measurements were higher in children with elevated lipid levels. Total cholesterol levels were positively related to full-fat dairy products and triglycerides levels to saturated fat percentage. Conclusions: Saturated fat was positively associated with elevated lipid levels in overweight and obese schoolchildren. These results reinforce the importance of healthy dietary habits since childhood in order to reduce the risks of cardiovascular diseases in adulthood. © 2012 Rinaldi et al.; licensee BioMed Central Ltd.

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The extracellular tannase from Emericela nidulans was immobilized on different ionic and covalent supports. The derivatives obtained using DEAE-Sepharose and Q-Sepharose were thermally stable from 60 to 75 °C, with a half life (t50) >24 h at 80 °C at pH 5. 0. The glyoxyl-agarose and amino-glyoxyl derivatives showed a thermal stability which was lower than that observed for ionic supports. However, when the stability to pH was considered, the derivatives obtained from covalent supports were more stable than those obtained from ionic supports. DEAE-Sepharose and Q-Sepharose derivatives as well as the free enzyme were stable in 30 and 50 % (v/v) 1-propanol. The CNBr-agarose derivative catalyzed complete tannic acid hydrolysis, whereas the Q-Sepharose derivative catalyzed the transesterification reaction to produce propyl gallate (88 % recovery), which is an important antioxidant. © 2012 Springer Science+Business Media Dordrecht.

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Purpose: To comparatively and prospectively compare in a randomized clinical trial, dentin hypersensitivity after treatment with three in-office bleaching systems, based on hydrogen peroxide at different concentrations, with and without light source activation. Methods: 88 individuals were included according to inclusion and exclusion criteria. Subjects were randomly divided into the following three treatment groups: Group 1 was treated with three 15-minute applications of hydrogen peroxide at 15% with titanium dioxide (Lase Peroxide Lite) that was light-activated (Light Plus Whitening Lase) with five cycles of 1 minute and 30 seconds each cycle, giving a total treatment time of 45 minutes; Group 2 was treated with three 10-minute applications of hydrogen peroxide at 35% (Lase Peroxide Sensy), activated by light (LPWL) same activation cycles than Group 1, with a total treatment time of 30 minutes; Group 3 was treated with only one application for 45 minutes of hydrogen peroxide at 35% (Whitegold Office) without light activation. Each subject underwent one session of bleaching on the anterior teeth according to the manufacturers' instructions. Dentin sensitivity was recorded with a visual analogue scale (VAS) at baseline, immediately after, and at 7 and 30 days after treatment using a stimulus of an evaporative blowing triple syringe for 3 seconds on the upper central incisors from a distance of 1 cm. A Kruskal-Wallis test followed by Mann-Whitney test was performed for statistical analysis. Results: All groups showed increased sensitivity immediately after treatment. Group 1 displayed less changes relative to baseline with no significant differences (P= 0.104). At 7 and 30 days after treatment, a comparison of VAS values indicated no significant differences between all groups (P= 0.598 and 0.489, respectively).

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Using sorghum silage, the effect of roughage/concentrate ratios was evaluated on nutrient intake, digestibility, ruminal parameters and methane production by beef cattle. Three treatments (0, 30 and 60% of concentrate in DM of the diet) were distributed in three Latin squares, with nine animals and three periods. Dry matter intake increased as the grain concentration in diet increased; pH showed opposite behavior. Methane emissions were lower for animals fed the diet exclusively with sorghum silage as compared with those fed 30% of concentrate, but was similar to that of animals receiving 60% of concentrate. Losses of ingested gross energy as methane were reduced by 33% when grain concentration was increased in the diet. Concentrations of propionic and butyric acids were greater in diets with grain concentrate; acetic acid concentration was not affected. Concentrate in diet increases available energy for the metabolism, measured by lower losses of ingested gross energy as ruminal methane. © 2013 Sociedade Brasileira de Zootecnia.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)