949 resultados para Color Doppler Sonography


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BACKGROUND: Epidemiological studies have shown that beer has positive effects on inhibiting atherosclerosis, decreasing the content of serum low-density lipoprotein cholesterol and triglycerides, by acting as in vivo free radical scavenger. In this research, the antioxidant activity of commercial Brazilian beers (n = 29) was determined by the oxygen radical absorbance capacity (ORAC) and 1,1 -diphenyl-2-picrylhydrazyl (DPPH(center dot)) assays and results were analyzed by chemometrics. RESULTS: The brown ale samples (n = 11) presented higher (P < 0.05) flavonoids (124.01 mg L(-1)), total phenolics (362.22 mg L(-1)), non-flavonoid phenolics (238.21 mg L(-1)), lightness (69.48), redness (35.75), yellowness (55.71), color intensity (66.86), hue angle (59.14), color saturation (0.9620), DPPH(center dot) values (30.96% inhibition), and ORAC values (3,659.36 mu mol Trolox equivalents L(-1)), compared to lager samples (n = 18). Brown ale beers presented higher antioxidant properties (P < 0.05) measured by ORAC (1.93 times higher) and DPPH (1.65 times higher) compared to lager beer. ORAC values correlated well with the content of flavonoids (r = 0.47; P = 0.01), total phenolic compounds (r = 0.44; P < 0.01) and DPPH (r = 0.67; P < 0.01). DPPH values also correlated well to the content of flavonoids (r = 0.69; P < 0.01), total phenolic compounds (r = 0.60; P < 0.01), and non-flavonoid compounds (r = 0.46; P = 0.01). CONCLUSION: The results suggest that brown ale beers, and less significantly lager beers, could be sources of bioactive compounds with suitable free radical scavenging properties. (C) 2010 Society of Chemical Industry

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In Experiment 1, color-naming interference for target stimuli following associated primes was greater in a group making a lexical decision to the prime than in a group reading the prime silently. High-frequency targets were responded to more quickly than low-frequency targets. In Experiment 2, with subjects naming the prime, there was evidence of associative interference when the prime and the target were grouped temporally but not when the intertrial interval was comparable with the prime-target interval. Associative primes presented at a short (120-msec) prime-target stimulus onset asynchrony facilitated color naming in Experiment 3. Taken together, the results suggest that the effect of faster processing of the base word in a color-naming task is facilitatory and that color-naming priming interference arises when associative prime processing increases conflict between word and color responses by enhancing phonological or articulatory activation of the base word.

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Many species of stomatopod crustaceans have multiple spectral classes of photoreceptors in their retinas. Behavioral evidence also indicates that stomatopods are capable of discriminating objects by their spectral differences alone, Most animals use only two to four different types of photoreceptors in their color vision systems, typically with broad sensitivity functions, but the stomatopods apparently include eight or more narrowband photoreceptor classes for color recognition. It is also known that stomatopods use several colored body regions in social interactions. To examine why stomatopods may be so 'concerned' with color, we measured the absorption spectra of visual pigments and intrarhabdomal filters, and the reflectance spectra from different parts of the bodies of several individuals of the gonodactyloid stomatopod species, Gonodactylus smithii. We then applied a model of multiple dichromatic channels for color encoding to examine whether the finely tuned color vision was specifically co-evolved with their complex color signals. Although the eye design of stomatopods seems suitable for detecting color signals of their own, the detection of color signals from other animals, such as reef fishes, can be enhanced as well. Color vision in G. smithii is therefore not exclusively adapted to detect its own color signals, but the spectral tuning of some photoreceptors (e.g. midband Rows 2 and 3) enhances the contrast of certain color signals to a large enough degree to make co-evolution between color vision and these rather specific color signals likely. Copyright (C) 2000 S. Karger AG, Basel.

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In the non-color-word Stroop task, university students' response latencies were longer for low-frequency than for higher frequency target words. Visual identity primes facilitated color naming in groups reading the prime silently or processing it semantically (Experiment 1) but did not when participants generated a rhyme of the prime (Experiment 3). With auditory identity primes, generating an associate or a rhyme of the prime produced interference (Experiments 2 and 3). Color-naming latencies were longer for nonwords than for words (Experiment 4). There was a small long-term repetition benefit in color naming for low-frequency words that had been presented in the lexical decision task (Experiment 5). Facilitation of word recognition speeds color naming except when phonological activation of the base word increases response competition.

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The apposition compound eyes of stomatopod crustaceans contain a morphologically distinct eye region specialized for color and polarization vision, called the mid-band. In two stomatopod superfamilies, the mid-band is constructed from six rows of enlarged ommatidia containing multiple photoreceptor classes for spectral and polarization vision. The aim of this study was to begin to analyze the underlying neuroarchitecture, the design of which might reveal clues how the visual system interprets and communicates to deeper levels of the brain the multiple channels of information supplied by the retina. Reduced silver methods were used to investigate the axon pathways from different retinal regions to the lamina ganglionaris and from there to the medulla externa, the medulla interna, and the medulla terminalis. A swollen band of neuropil-here termed the accessory lobe-projects across the equator of. the lamina ganglionaris, the medulla externa, and the medulla interna and represents, structurally, the retina's mid-band. Serial semithin and ultrathin resin sections were used to reconstruct the projection of photoreceptor axons from the retina to the lamina ganglionaris. The eight axons originating from one ommatidium project to the same lamina cartridge. Seven short visual fibers end at two distinct levels in each lamina cartridge, thus geometrically separating the two channels of polarization and spectral information. The eighth visual fiber runs axially through the cartridge and terminates in the medulla externa. We conclude that spatial, color, and polarization information is divided into three parallel data streams from the retina to the central nervous system. (C) 2003 Wiley-Liss, Inc.

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Objective: To evaluate the impact of systematic use of intraoperative Doppler ultrasound during microsurgical subinguinal varicocele repair. Design: Prospective clinical study. Setting: Andrology laboratory and male infertility section of the urology department of a tertiary care hospital. Patient(s): Two hundred and thirteen men with clinical varicocele. Intervention(s): Subinguinal microsurgical varicocele ligation using an intraoperative vascular Doppler flow detector. Main Outcome Measure(s): Number of veins ligated, lymphatic spared, arteries identified or accidentally ligated. Result(s): A statistically significant greater number of arteries were identified and preserved when intraoperative vascular Doppler was used. In addition, the average number of internal spermatic veins ligated was statistically significantly greater in the same group. Accidental artery ligation occurred in two cases (1.1%) in which the Doppler was not applied. There was no statistically significant difference in number of lymphatics spared between groups. Conclusion(s): Our findings showed that concomitant use of intraoperative vascular Doppler during microsurgical varicocelectomy allows more arterial branches to be preserved, and more internal spermatic veins are likely to be ligated. This device should be considered an attractive tool to improve surgical outcomes and safety. (Fertil Steril (R) 2010; 93: 2396-9. (C)2010 by American Society for Reproductive Medicine.)

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Objectives: The aim of this study was to determine the correlation between ductus venosus (DV) Doppler velocimetry and fetal cardiac troponin T (cTnT). Study design: Between March 2007 and March 2008, 89 high-risk pregnancies were prospectively studied. All patients delivered by cesarean section and the Doppler exams were performed on the same day. Multiple regression included the following variables: maternial age, parity, hypertension, diabetes, gestational age at delivery, umbilical artery (UA) S/D ratio, diagnosis of absent or reversed end-diastolic flow velocity (AREDV) in the UA, middle cerebral artery (MCA) pulsatility index (131), and DV pulsatility index for veins (PIV). Immediately after delivery, UA blood samples were obtained for the measurement of pH and cTnT levels. Statistical analysis included the Kruskal-Wallis test and multiple regressions. Results: The results showed a cTnT concentration at birth >0.05 ng/ml in nine (81.8%) of AREDV cases, a proportion significantly higher than that observed in normal UA S/D ratio and UA S/D ratio >p95 with positive diastolic blood flow (7.7 and 23.1%, respectively, p < 0.001). A positive correlation Was found between abnormal DV-PIV and elevated cTnT levels in the UA. Multiple regression identified DV-PIV and a diagnosis of AREDV as independent factors associated with abnormal fetal cTnT levels (p < 0.0001, F(2.86) = 63.5, R = 0.7722). Conclusion: DV-PIV was significantly correlated with fetal cTnT concentrations at delivery. AREDV and abnormal DV flow represent severe cardiac compromise, with increased systemic venous pressure, and a rise in right ventricular afterload, demonstrated by myocardial damage and elevated fetal cTnT. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

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The pocilloporin Rtms5 and an engineered variant Rtms5(H146S) undergo distinct color transitions (from blue to red to yellow to colorless) in a pH-dependent manner. pK(a) values of 4.1 and 3.2 were determined for the blue (absorption lambda(max), 590 nm) to yellow (absorption lambda(max), similar to 453 nm) transitions of Rtms5 and Rtms5H(146). The pK(a) for the blue-yellow transition of Rtms5H(146S) increased by 1.4 U in the presence of 0.1 M KI, whereas the pK(a) for the same transition of Rtms5 was relatively insensitive to added halides. To understand the structural basis for these observations, we have determined to 2.0 A resolution the crystal structure of a yellow form of Rtms5(H146S) at pH 3.5 in the presence of iodide. Iodide was found occupying a pocket in the structure with a pH of 3.5, forming van der Waals contacts with the tyrosyl moiety of the chromophore. Elsewhere, it was determined that this pocket is occupied by a water molecule in the Rtms5(H141S) structure (pH 8.0) and by the side chain of histidine 146 in the wild-type Rtms5 structure. Collectively, our data provide an explanation for the observed linkage between color transitions for Rtms5(H146S) and binding to halides.

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To determine reference values for tissue Doppler imaging (TDI) and pulsed Doppler echocardiography for left ventricular diastolic function analysis in a healthy Brazilian adult population. Observations were based on a randomly selected healthy population from the city of Vitoria, Espirito Santo, Brazil. Healthy volunteers (n = 275, 61.7% women) without prior histories of cardiovascular disease underwent transthoracic echocardiography. We analyzed 175 individuals by TDI and evaluated mitral annulus E`- and A`-waves from the septum (S) and lateral wall (L) to calculate E`/A` ratios. Using pulsed Doppler echocardiography, we further analyzed the mitral E- and A-waves, E/A ratios, isovolumetric relaxation times (IRTs), and deceleration times (DTs) of 275 individuals. Pulsed Doppler mitral inflow mean values for men were as follows: E-wave: 71 +/- 16 cm/sec, A-wave: 68 +/- 15 cm/sec, IRT: 74.8 +/- 9.2 ms, DT: 206 +/- 32.3 ms, E/A ratio: 1.1 +/- 0.3. Pulsed Doppler mitral inflow mean values for women were as follows: E-wave: 76 +/- 17, A-wave: 69 +/- 14 cm/sec, IRT: 71.2 +/- 10.5 ms, DT: 197 +/- 33.3 ms, E/A ratio: 1.1 +/- 0.3. IRT and DT values were higher in men than in women (P = 0.04 and P = 0.007, respectively). TDI values in men were as follows: E`S: 11 +/- 3 cm/sec, A`S: 13 +/- 2 cm/sec, E`S/A`S: 0.89 +/- 0.2, E`L: 14 +/- 3 cm/sec, A`L: 14 +/- 2 cm/sec, E`L/A`L: 1.1 +/- 0.4. E-wave/ E`S ratio: 6.9 +/- 2.2; E-wave / E`L ratio: 4.9 +/- 1.7. In this study, we determined pulsed Doppler and TDI derived parameters for left ventricular diastolic function in a large sample of healthy Brazilian adults. (Echocardiography 2010;27:777-782).

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Objective. To correlate Doppler results with hematological indices at birth in small-for-gestational-age (SGA) fetuses. Design. Prospective study. Setting. Tertiary teaching hospital, Sao Paulo, Brazil. Population. One hundred singleton pregnancies with SGA fetuses of > 27 weeks gestational age. Methods. All women had Doppler velocimetry of the umbilical arteries, middle cerebral artery, and ductus venosus within < 72 hours prior to delivery. After birth, umbilical artery blood was collected for hematological analysis. Main outcome measures. The association between fetal Doppler velocimetry pulsatility index (PI) and some hematological indices. Results. Umbilical artery PI showed a positive correlation with nucleated red blood cell count in the umbilical cord (r = 0.46; p<0.01), and a negative correlation with platelet count (r = -0.53; p<0.01) and white blood cell count (r = -0.42; p<0.01). Middle cerebral artery PI was positively correlated with platelet count (r = 0.43; p<0.01) and white blood cell count (r = 0.38; p<0.01), and was negatively correlated with nucleated red blood cell count (r = -0.39; p<0.01). The ductus venosus pulsatility index showed a positive correlation with nucleated red blood cell count (r = 0.36; p<0.01), and a negative correlation with platelet count (r = -0.37; p<0.01) and white blood cell count (r = -0.26; p<0.01). Conclusion. A significant positive or negative correlation between nucleated red blood cell, platelet and white blood cell counts, and Doppler indices suggests an association between placental insufficiency and the fetal hematological response.

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Objective: To evaluate the relationship between ductus venosus Doppler findings on the day of delivery and postnatal outcomes in pregnancies with absent or reversed end-diastolic (ARED) flow in the umbilical arteries. Study design: Postnatal outcomes of 103 newborns of pregnancies with a diagnosis of ARED flow on Doppler velocimetry of the umbilical arteries were analyzed retrospectively between January 1997 and December 2004. Single pregnancies and fetuses without malformations were included. The cases were divided into two groups according to the flow during atrial contraction (a-wave) in the ductus venosus on the day of delivery: group A, 20 cases with absent or reversed flow in the ductus venosus and group B, 83 cases with positive flow. The results were analyzed statistically using the chi-square test, Fisher`s exact test and the Mann-Whitney U test with the level of significance set at 5%. Results: All newborns were delivered by cesarean section. Gestational age was similar in the two groups (group A: 30 weeks and group B: 30.9 weeks, P = 0.23). Absent or reversed ductus venosus flow was associated with the following adverse postnatal outcomes: lower birthweight (P < 0.001), lower Apgar scores in the first (P = 0.001) and fifth minute (P = 0.001), a higher frequency of orotracheal intubation (P = 0.001) and pH at birth less than 7.20 (P < 0.001), pulmonary hemorrhage (P = 0.03), thrombocytopenia (P = 0.02), hypoglycemia (P = 0.01), intracranial hemorrhage (P = 0.02), and postnatal death (P = 0.007). Conclusion: The study of ductus venosus flow may provide additional information regarding the best time for interruption of pregnancies with ARED flow in the umbilical arteries characterized by extreme prematurity. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

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Objective: To analyze the effects of sildenafil citrate on clitoral blood flow and sexual response in postmenopausal women with orgasmic dysfunction. Method: In this randomized, double-blind, placebo-controlled trial 22 women received a 50-mg dose of sildenafil (n=11) or placebo (n=11) daily for 15 days. The Golombok Rust Inventory of Sexual Satisfaction (GRISS) was used for subjective evaluation of the sexual-response cycle. Clitoral blood flow was measured by color and pulse Doppler at baseline, after 1 hour of taking the first dose, and after 15 days of treatment. Results: Blood flow was significantly more improved in the sildenafit than in the placebo group (P<0.05), and a positive correlation between Doppler values and GRISS scores was noted in the sildenafil group after only 15 days of treatment. Conclusion: Sildenafil may improve clitoral blood flow and increase the GRISS scores in postmenopausal women with orgasmic dysfunction. (C) 2008 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.