120 resultados para Repetition priming
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Background and Objectives - A controversy exists in the literature regarding the effects of the acute administration of magnesium on the cardiovascular system of animals and humans. The purpose of this study was to evaluate the effects of hypermagnesemia on the cardiovascular hemodynamics of dogs. Methods - Sixteen mongrel dogs were anesthetized with pentobarbitone 30 mg.kg-1 and submitted to volume expansion with Ringer's solution (0.4 ml.kg-1.min-1 and mechanical ventilation with room air. In this model, the hemodynamic repercussions of the following drugs and doses were studied. pentobarbitone 5 mg.kg-1 Group 1, control - and the association of pentobarbitone and magnesium sulphate (MS), at the dose of 140 mg.kg-1 injected in 15 minutes, followed by an infusion of 80 mg.kg-1.h-1 - Group 2. The parameters studied were: heart rate, blood pressure, inferior vena cava pressure, cardiac index, systolic index and peripheral resistance index, evaluated at 5 different moments: 15(M1), 30(M2), 60(M3) and 75(M4) minutes after the first suppplementary dose of pentobarbitone and 15 minutes (M5) after the second supplementary dose. In Group 2, the moments M3, M4, M5 corresponded to 15, 30 and 60 minutes after the priming dose of magnesium sulphate. Results - Group 1 animals exhibited tachycardia since the beginning of the experiment. There was a decrease in the cardiac index, in the systolic index and an increase in the inferior vena cava pressure. Group 2 animals also exhibited tachycardia, but heart rate decreased after MS infusion. The blood pressure and the peripheral resistance index decreased. The systolic index increased and the cardiac index decreased only at the end of the experiment. Conclusions: The antiadrenergic effects of MS could have been responsible for the decrease in heart rate. The vasodilating effects of the magnesium induced the decrease in the peripheral resistance index. The systolic index increased, showing that myocardial depression did not occur.
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Background and objectives - The use of magnesium sulphate for the prevention of seizures in pre-eclampsia may induce hypermagnesemia. Clinical and experimental studies are not in agreement about the effects of magnesium on the renal hemodynamics and function. We therefore studied the effects of hypermagnesemia on the renal hemodynamics and function of dogs anesthetized with pentobarbitone. Methods - Sixteen mongrel dogs were anesthetized with pentobarbitone 30 mg.kg-1 and submitted to extracellular ) and mechanical ventilation with room air. The dogs were volume expansion with Ringer's solution (0.4 ml.kg.min allocated into two groups of 8 animals, for the study of renal hemodynamics and function following the administration of 5 mg.kg-1 of pentobarbitone (Group 1 - control or of pentobarbitone associated with magnesium sulphate in the dose (Group 2). The parameters studied were: PAH of 140 mg.kg, administered in 15 minutes, followed by 80 mg.kg-1.h-1 clearance, creatinine clearance, osmolar clearance, free water clearance, renal blood flow, renal vascular resistance, filtration fraction, urinary volume, plasmatic and urinary osmolarity, urinary and fractionary excretion of sodium and potassium, measured at five moments: 15 (M1), 30 (M2), 60 (M3) and 75 (M4) minutes after the first supplementary dose of pentobarbitone and 15 minutes (M5) after the second supplementary dose in Group 1. In Group 2, the moments M3, M4, M5 were 15, 30 and 60 minutes after the priming dose of magnesium sulphate and during the maintenance dose. Results - In Group I no significant changes were observed in renal hemodynamic parameters and creatinine clearance. The extracellular volume expansion increased urinary volume and decreased urinary osmolarity as a consequence of sodium, potassium and free water clearance. The fractionary excretion of sodium was maintained. The plasmatic osmolarity increased. In Group 2, renal hemodynamic parameters and creatinine clearance were also maintained. There was an increase in renal sodium clearance, as detected by the increase in the fractionary excretion of sodium. Conclusions - Magnesium sulphate did not produce significant changes in renal hemodynamics and facilitated the renal excretion of sodium in dogs anesthetized with pentobarbitone.
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Three species of filamentous fungi, Aspergillus niger, Penicillium fellutanum and Mucor hiemalis, were selected and cultivated in vinasse media with different addition of molasses, pasteurized to 85°C for 30 minutes and with pH = 5.0. The microorganisms, previously adapted to the respective medium for 48 hours, from a solution of 107 spores.ml-1, were cultivated in pure and mixed cultures in Erlenmeyer vessel of 500ml, to 30°C, with constant agitation of 170 rpm, for 24, 48 and 72 hours, with four repetition for each samples. The biomass was separated by vacuum filtration in filter Whatman #1 and dried in oven at 105°C until right weight, the obtained liquid was submited to COD analysis. The datas were statistically analysed using a response surface methodology, to improve the effect on the molasses proportion and culture time, in the biomass production by microorganism in research. According to the obtained results (5.02% of molasses, 55.59h, 70% of spores solution of A. niger and 30% of spores solution of P. fellutanum), cultivating was carried out in Microferm Fermentor New Brunswick for 48 hours at 300 rpm, aired at 1v/v/m, using 5 liters of medium added with 5.0% of molasses on the conditions above described. The average of the results obtained (6.81g.l-1) was higher than the confidence interval (5.937 ; 6.369) and was inside the prediction interval (4.471 ; 7.834) both of them significant at 95% by the statistical test employed.
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This work develops a methodology (using the degree-days concept and linear regression), to forecast the duration of phenological phases in crops. An experiment was conducted in the greenhouse with three cultivars of cowpea (Vigna unguiculata (L.) Walp.), cv. Califórnia-781, Tvx 5058-09C and IT 81D-1032. The methodology was based on the relative thermal efficiency rate, determined for each species or cv. The results show that the proposed methodology may be a good alternative in works involving crops, especially because it does not require the repetition of the experiments.
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A simple constant-current electrocutaneous stimulator for high-impedance loads using low-cost, standard high-voltage components is presented. A voltage-regulator powers an oscillator built across the primary of a transformer whose secondary delivers, after rectification, the high-voltage supply to switched current-mirrors in the driving stage. Since the compliance high-voltage is proportional to the stimulation current, overall power consumption is minimized. By adjusting the regulated voltage, control of the pulsed-current amplitude is achieved. A prototype with readily available components features stimulation currents of amplitude and pulsewidth in the range 0≤Iskin≤20mA and 50μs ≤Tpulse≤1ms, respectively. Pulse-repetition spans from 1 Hz to 10Hz. Worst-case ripple is 3.7% @Iskin=1mA. Measured pulse fall-time is shorter than 32μs. Overall consumption is 4.4W @Iskin=20mA. Subject isolation from line is 4KV.
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In this work we present a description of the advertisement call of H. jimi, the locality type, and of H. elianeae, until now unknown in the literature. Field activities were carried out from August 1997 through June 1999; recordings were made in two open-area environments in the Botucatu region, São Paulo State. Vocalizations of 100 individuals (49 H. jimi and 51 H. elianeae) were recorded; nine characteristics of the advertisement call were examined. The advertisement calls of both species consist of consecutive series of simple notes with relatively fast repetition rates. Males of H. jimi and H. elianeae presented two patterns of note emission: one emitted by individuals beginning vocalization activity or isolated from the aggregate, and another emitted by males in chorus activity interacting with closely neighboring males. A significant difference was verified in the temporal structure of the two vocalization patterns.
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The purpose of this study was to identify the Electromyographic Fatigue Threshold (EMG FT) of the biceps brachii muscle bilaterally during the elbow flexion in tests performed in different times: 30 second test, 1 minute test and fatiguing test, in concentric (CC) and eccentric (EC) phases. Nine healthy young men performed the elbow flexion with loads corresponding at 25%, 35% and 45% of the one repetition maximum (1-RM) in separate days. The results indicated that the test applied for the biceps brachii muscle during elbow flexion induced a progressive increment of EMG activity with time indicating muscle fatigue and allowed the identification of the EMG FT. The three tests presented no difference of EMG FT between CC and EC phases bilaterally.
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We analysed spatial and acoustic partitioning among four species of Hyla belonging to two species-groups: nana (H. nana and H. sanborni) and rubicundula (H. elianeae and H. jimi). Field activities were conducted at three permanent ponds, from 1998 through 2001. Four attributes of the calling sites were analysed: perch height, distance of the perch from the edge of the pond, type of perch (vegetation) and the individual's position on the perch. There was extensive overlap in the four calling-site variables analysed. However, we found spatial segregation did occur in calling site height and the distance of perches from pond edges. Bioacoustic analyses revealed behavioural differences among species in calling activity, both time of onset and peak calling in chorus. There was acoustic partitioning among species the fundamental frequency of the advertisement calls, principally as a function of the temporal structure (e.g. note duration, rate of note repetition, duration and rate of repetition of the calling pulses). We propose that differences in physical attributes of calling site and in characteristics of calls allow these species to exist in sympatry.
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The reproducibility of measurements of alveolar bone loss on radiographs may be a problem on epidemiologic studies, as they are based on comparisons of the diagnosis of various examiners. The aim of the present research paper was to assess the inter- and intra-examiner reproducibility of measurements of the interproximal alveolar bone loss on non-manipulated digital radiographs and after the application of image filters. Five Oral Radiologists measured the distance between the cementoenamel junction (CEJ) to the alveolar crest or to the deepest point of the bony defect on 12 interproximal digital radiographs of molars and bicuspids of a dry human skull. The digital manipulation and the linear measurements were obtained with the Trophy Windows software (Throphy®). For each image, six different versions were created: 1) non-manipulated; 2) bright-contrast adjustment; 3) negative; 4) negative with brightness-contrast adjustment; 5) pseudo-colored; 6) pseudo-colored with brightness-contrast adjustment. In order to prevent interpretation bias because of the repetition of measurements, the examiners measured the radiographs in a random sequence. The two-way ANOVA test at 5% level of significance to compare the means of readings of the same operator with each filter indicated p<0.05 for the majority of operators, while the comparison between the mean values of operators using the same filter indicated p>0.05 for all filters. Based on the results, we concluded that linear measurements of interproximal alveolar bone loss on digital radiographs are highly reproducible among examiners. Nevertheless, the application of image filters significantly influenced the degree of intra-examiner reproducibility. Some filters even reduced the reproducibility of intra-examiner readings.
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Muscle fatigue can be a limiting factor to determine index as the electromyographic fatigue threshold (EMGFT) due the alterations in motivation and disconfots. This way, the purpose of this study was to identify the right biceps brachii and left biceps brachii obtained from repetitive elbow flexions at each 10% of total time. Nine healthy subjects performed the exercise named biceps curl until exhaustion with 25%, 35%, and 45% of one repetition maximum, in three different days. EMG amplitude (root mean square - RMS) was obtained for concentric contractions during these load levels and correlated with time to determine the slope values for each load and them detemine the EMGFT. The EMGFT was obtained within of each 10% of total time and they were compared by analysis of variance. The results showed a progressive increase in RMS with time, for both muscles in all loads, characterizing the muscle fatigue process, and for the EMGFT values ware not found predominantly significant differences between the execution time, as well as between muscles (right biceps × left biceps). This protocol allowed to identify the EMGFT to both muscles during the biceps curl, which was similar at different percentage of total time, indicating the possibility to reduce the length of the contraction test without the need to maintain the contraction until exhaustion. Further studies are needed to evaluate the applicability of this method to determining the effects on performance.
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This research was aimed at verifying the occurrence of possible alterations in liver, kidney and intestine of bullfrog tadpoles in stage 42 fed with diets containing different concentrations (0.0; 0.2; 0.5; 1.0 and 1.5%) of propolis hydroalcoholic extract. The experiment was carried out in laboratory of Aquatic Organisms Nutrition from Aquaculture Center of UNESP, where 1,400 tadpoles in stage 26 were used and distributed in twenty experimental aquariums. In the end of experiment (60 days) three tadpoles from each repetition were sacrificed and kidney, liver and intestine samples were collected to processing of histological slices in Histology's Laboratory pertaining to Department of Morphology and Physiology from FCAV - UNESP. Samples were fixed, dehydrated, stained in HE, analysed, photomicrographed and thickness of intestinal epithelium was measured. Histological disturbances in tadpoles's intestine, kidneys and liver were not observed. Thickness of intestinal epithelium from the same ones was not influenced (P>0.05) by propolis concentrations.
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Background: Vaccination of neonates is generally difficult due to the immaturity of the immune system and consequent higher susceptibility to tolerance induction. Genetic immunization has been described as an alternative to trigger a stronger immune response in neonates, including significant Th1 polarization. In this investigation we analysed the potential use of a genetic vaccine containing the heat shock protein (hsp65) from Mycobacterium leprae (pVAXhsp65) against tuberculosis (TB) in neonate mice. Aspects as antigen production, genomic integration and immunogenicity were evaluated. Methods: Hsp65 message and genomic integration were evaluated by RT-PCR and Southern blot, respectively. Immunogenicity of pVAXhsp65 alone or combined with BCG was analysed by specific induction of antibodies and cytokines, both quantified by ELISA. Results: This DNA vaccine was transcribed by muscular cells of neonate mice without integration into the cellular genome. Even though this vaccine was not strongly immunogenic when entirely administered (three doses) during early animal's life, it was not tolerogenic. In addition, pVAXhsp65 and BCG were equally able to prime newborn mice for a strong and mixed immune response (Th1 + Th2) to pVAXhsp65 boosters administered later, at the adult life. Conclusion: These results suggest that pVAXhsp65 can be safely used as a priming stimulus in neonate animals in prime-boost similar strategies to control TB. However, priming with BCG or pVAXhsp65, directed the ensuing immune response triggered by an heterologous or homologous booster, to a mixed Th1/Th2 pattern of response. Measures as introduction of IL-12 or GM-CSF genes in the vaccine construct or even IL-4 neutralization, are probably required to increase the priming towards Th1 polarization to ensure control of tuberculosis infection. © 2007 Pelizon et al; licensee BioMed Central Ltd.
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Purpose: To evaluate the influence of the brush type as a earner of priming adhesive solutions and the use of paper points as a remover of the excess of these solutions on the push-out bond strength of resin cement to bovine root dentin. The null hypotheses were that brush type and the use of paper points do not affect the bond strength. Materials and Methods: The canals of 80 single-root bovine roots (16 mm in length) were prepared at 12 mm using the preparation drill (FRC Postec Plus, Ivoclar). Half of each root was embedded in acrylic resin and the specimens were divided into 8 groups, considering the factors brush type (4 levels) and paper point (2 levels) (n = 10): Gr 1: small microbrush (Cavi-Tip, SDI); Gr 2: Microbrush (Dentsply); Gr 3: Endobrush (Bisco); Gr 4: conventional brush (Bisco); Gr 5: Cavi-Tip (SDI) + paper points; Gr 6: Microbrush (Dentsply) + paper points; Gr 7: Endobrush (Bisco) + paper points; Gr 8: conventional brush (Bisco) + paper points. The root dentin was treated with a multistep total-etch adhesive system (All Bond 2). The adhesive system was applied using each microbrush, with and without using paper points. One fiber post was molded with addition silicon and 80 posts were made of resin cement (Duolink), The resin posts were luted (Duolink resin cement), and the specimens were stored for 24 h in water at 37°C. Each specimen was cut into 4 disk-shaped samples (1.8 mm in thickness), which were submitted to the push-out test. Results: The brush type (p < 0.0001) (small microbrush > microbrush = endobrush = conventional brush) and the use of paper points (p = 0.0001) (with > without) influenced the bond strength significantly (two-way ANOVA). The null hypotheses were rejected. Conclusion: The smallest brush (Cavi-Tip) and the use of paper points significantly improved the resin bond to bovine root dentin.
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The aim of this study was the selection of Corymbia citriodora provenances for three different kinds of soils occurring in Luiz Antônio Experimental Station, São Paulo, Brazil (Latossolo Vermelho, Areia Quartzosa and Latossolo Roxo). The provenance test was established in 1983, with ten Corymbia citriodora provenances and one Eucalyptus grandis as control, original from a seed production area. The trials were established in a random block design with 11 treatments, three repetition and square plots with 25 trees. In 2008, there were evaluations of height, diameter at breast height (DBH, 1.3 m), stem form and survival. Significant differences among soils and provenances were detected for the growth traits, stem form and survival in all those studied soils. Significant provenance and soil interactions were not detected. All provenances showed higher growth in height and DBH in Purple Latosol. The control had a higher growth rate in relation to highness, DBH and stem form than Corymbia citriodora provenances in all the studied soils, but it presented, generally, a lower survival rate than Corymbia citriodora provenances. Pederneiras (11) Corymbia citriodora provenance presented a higher performance in relation to highness and DBH in all kinds of soils, and Gilgandra (4) provenance, original from Australia, had the worst development. Therefore, Pederneiras (11) provenance is, therefore, the best choose for reforestations in all those studied soils.
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Introduction. Physical activity can provide long-term benefits for systemic lupus erythematosus (SLE). Objective. This study sought to demonstrate the effects of progressive resistance training on the muscular strength, bone mineral density (BMD) and body composition of pre-menopausal women with SLE undergoing glucocorticoid (GC) treatment. Materials and Methods. This is the case report of a 43-year-old African-South American premenopausal woman with non-extensive SLE and low bone density. A six-month program with three bimonthly cycles of 70%, 80%, and 90% intensity according to the 10 maximum-repetition test was used. Dual-energy X-ray absorptiometry (DXA) was used to measure the BMD, T-scores and body composition, and indirect fluorescence was used to measure the levels of antinuclear antibodies. Student's t-test was used. Results. Statistical improvement was noted in all strength exercises, including the 45° leg press (Δ%=+50%, p<0.001) and knee extension (Δ%=+15%, p=0.003) to maintain the BMD of the L2-L4 lumbar (Δ%=+0.031%; p=0.46) as well as the trochanter (Δ%=+0.037%; p=0.31) and BMI (Δ%=-0.8, p=0.54). Conclusion. In this case study, the presented methodology had a positive effect on strength and contributed to the maintenance of BMD and body composition in a woman with SLE undergoing GC treatment. © 2012 Revista Andaluza de Medicina del Deporte.