889 resultados para Ácido bórico.


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The effect of indol-3-acetic acid (lAA) and calcium (Ca + + ) on the flow of water through Nitella celIs was studied. Nitella cernua Braun was selected because it is possible tb study the permeability of a single isolated cell. IAA was used at a concentration of 0,28 10-3 M and CaCI2 at 10-3 M. The effect of IAA on the isolated celIs was confirmed by the increase of plasticity and permeability of the plasmalema of th.e treated cells with absorption and a consequent elimination of water. The effect was reversed by Ca ions.

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This experiment was carried out to evaluate the effect of the addition of fumaric acid to broiler diet on birds performance. One thousand and eighty Hubbard day-old broiler chicks were alloted in a randomized block design, six treatments with two replicates of males, and four replicates of females. Three basal diets were formulated to meet the nutritional requirements in each growing phase: from 1 to 21 days, 21 to 37 days and 37 to 45 days. Treatments consisted first in the addition of growth promoter to 0.75 and 1.0%, of fumaric acid. The group treated without of both growth promoter and fumaric acid presented a higher intake and a smaller feed:gain ratio in relation to the fumaric acid treated groups. However, there were no differences among groups treated with growth promoter and fumaric acid. The contrasts did not show any difference among weight gain, carcass yield and abdominal fat. The addition of fumaric acid levels to the diets promoted reduction of feed intake, without any effect on weight gain, improving, therefore, the feed/gain ratio. A digestibility experiment was carried out, using 30 Hy-Line roosters, to determine apparent metabolyzed energy (AME), corrected by nitrogen of the diets containing 0.0, 0.5 and 1.0% of the acid. An increase on the AME of the diets was observed with fumaric acid addition.

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Calla lily (Zantedeschia aethiopica) is appreciated as cut flower and for the composition of gardens. However, many pathogens affect this species. By the traditional method of propagation, some units of new seedlings can only be produced annually. Tissue culture allows fast large-scale clonal propagation and provides healthy uniform plants. During the in vitro process, type and concentration of growth regulator could affect the growth of seedlings. Thus, the aim of this work was to determine sucrose and GA(3) concentrations to increase the efficiency of the in vitro multiplication of calla lily. After 60 days, the length of the above ground part and the roots, the number of sprouts, roots and leaves, above ground part and root fresh weight of seedlings were evaluated. The experimental design was entirely randomized with four replications. It was necessary the addition of 60.5 g L-1 sucrose associated to 5 mg L-1 GA(3) to obtain hight sprouts number. For higher length of the above ground part the addition of 45.3 g L-1 sucrose and 10 mg L-1 GA(3) was enough. Better results in the root length and number of roots were observed only in the sucrose presence, in concentrations in the range of 51.13 - 56.5 g L-1.

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The aim of this work was evaluate the physiological indicators of association between water deficiency and soil acidity, by determining the nitrate reductase activity, the levels of free proline and initial growth of the root system of seedlings of sugarcane cv. IAC91-5155. After 30 days, the seedlings were transferred to plastic pots with 12 dm3 of dystrophic alic Red Latosol (Oxisol) and submitted to association of three treatments of water availability: no stress (70%), moderate stress (55%) and severe stress (40%), in according with field capacity and three acidity treatments: no stress (55%), moderate stress (33%) and severe stress (23%), considering the base saturation. The experimental design was that of random blocks under factorial scheme of 3x3, with four replicates. After 60 days under the stress association, the levels of free proline, the nitrate reductase activity and the growth of the sugarcane roots system were evaluated in seedlings of sugarcane. The nitrate reductase enzyme activity can be considered a physiological indicator of the effect of the association of acid and water stress in moderate conditions in soil, while the free proline can be considered physiological indicator to both stress in severe conditions. Water deficiency increasing reduced growth of sugarcane roots.

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In eighteen dogs, the effects of halothane (0,75% and 1,5%) associated with a normo and hypercapnia (PaCO2 from 30 to 80 mmHg) on acid-base balance were studied. Determinations of creatine clearance, urinary flow, urinary acid excretion, and urinary ammonium excretion were made. Based on the results, it is concluded that halothane associated with hypercapnia decreases the glomerular filtration rate, the urinary flow, the urinary pH and the urinary bicarbonate and sodium excretion, increases the plasmatic bicarbonate concentration, the bicarbonate reabsorbed, the urinary acid excretion and the urinary ammonium excretion, but does not alter the base excess.

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The skin pigmentation caused by ultraviolet light irradiation as a defense against the carcinogenic action of solar light may lead to early skin aging and to hyperchromia, which treatment requires the use of photo-protective, depigmenting and rejuvenating agents. Recently, there have been used many substances for the prevention and/or treatment of skin aging as well as to lowering the skin pigmentation. Glycolic acid is the alpha-hydroxy acid most commonly used in cosmetic and dermatological prepatations. This use is due to its depigmentating and rejuvenating properties and its efficacy at different concentrations, when incorporated to different kind of excipients.

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Fungi producing γ-linolenic acid (GLA) were isolated from soil of the Ecological Station of Juréia-Itatins, SP. This essential fatty acid has aroused great interest due to its increasing by applications in pharmaceutical industry. The GLA production by zygomycetous fungi is an alternative way of comparing seed extraction. Thirty-two zygomycetous strains of Mucorales were isolated, most of them belonging to Mucor genus. The GLA production was evaluated after 4 days of incubation at 25°C on a rotary shaker at 150 rpm in medium containing 2% glucose, and 1% yeast extract, following new medium addition (20%) and incubation for an additional period of 3 days at 12°C, without agitation. The GLA production varied according to the microorganism and the strain.

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Retinoic acid, which has been prescribed for some forms of acne since 1962, is subject to isomerization provoked by atmospheric oxygen and ambient light. Therefore it is very important to keep this material intact through the use of antioxidants. We tested two antioxidants: various concentrations of butylhydroxytoluene or BHT, widely used in cosmetic and dermatological preparations, and vitamin E, found in grape oil, an ingredient of skin lotion. Recently prepared lotions were subject to heat stress and the residual concentrations of retinoic acid determined at predetermined intervals through UV spectrophotometry. The shelf life of the various preparations were determined by the Arrhenius equation. The antioxidants helped conserve the retinoic acid, however, there was no synergism in antioxidant activity between the vitamin E in the grape seed oil and BHT.

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This paper supplies a revision about the main techniques of extraction, clean-up and pre-concentration of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) in water and soil samples, as well as chromatographic methods and immune assays for its identification and quantification.

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This study correlated the solid preoperative fasting periods with plasma glycemia, serum cortisol, condition clinic and acid-base balance in dogs submitted to inhalation of general anaesthesia. Eight adults, animals were distributed into three groups in accordance with solid preoperative fasting: group 1 (12 hours), group 2 (18 hours) and group 3 (24 hours). Gastric emptying was observed and following this animals were submitted to the same anesthetic procedure. Heart and respiratory rate, rectal temperature, capillary refill time, percent hydration and noninvasive arterial pressure determined before and after Acepromazine and every 10 minutes during anaesthesia, included ETCO 2; values blood gas (pH, PaCO 2, PaO 2, HCO 3, TCO 2, SaO 2, BE), glycemic and serum cortisol were analyzed before MPA and each 30 minutes during anaesthesia. In recovery anaesthetic, glycemia and serum cortisol were repeated. During anaesthesia there were little cardiovascular and respiratory alteration not having interference of the preoperative fasting periods. Animals with 12 hours of the preoperative fasting showed a higher rise in glycemia levels than others groups in recovery anaesthetic. Serum cortisol wasn't influenced by fasting. Solid preoperative fasting independent of the duration describe a discreet respiratory alkalosis. All animals showed good clinical condition in all three groups. Solid preoperative fasting of the 18 hours is recommended to ensure a complete absence of the solid food contents in stomach.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Introduction: The use of dermal filling techniques for soft tissue augmentation has greatly increased in recent years. Hyaluronic acid is one of the most used temporary dermal fillers in the treatment of facial wrinkles, furrows, and folds due to its effectiveness and safety. Objective: To evaluate the efficacy and safety of Perfectha®, a new hyaluronic acid filler, for nasolabial folds and lip correction. Methods: Open, multicenter study comprising 87 women. Efficacy was evaluated by the Global Aesthetic Improvement Scale and the Wrinkle Severity Rating Scale. Safety was evaluated through observation and the reporting of side effects. Results: One week after the injection of the filler, improvement in nasolabial folds and lips was observed in 86% and 89% of the women, respectively. Mild or moderate transient inflammatory reaction and ecchymoses occurred in 15% and 9% of patients, respectively, mainly in nasolabial folds. Two patients presented labial herpes simplex after treatment of the lips. The good results were maintained in 76% and 57% of women for nasolabial folds and in 72% and 45% of women for lips after 3 and 6 months, respectively. Conclusion: Perfectha® was effective and safe for these indications.

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Fertirrigation with phosphoric acid has been considered as an option to avoid drips from clogging. In some cases, this acid cause soil acidification and it can be substituted bypotassium hydroxide. This study had the objective of evaluating the effects of different phosphoric acid and potassium hydroxide doses, applied via fertirrigation, on soil fertility, plant nutrition and lettuce yield, compared to the conventional fertilization system. The experiment was carried out in greenhouse, in the College of Agricultural Sciences, FCA/UNESP, Botucatu-SP-Brazil. The experimental design was the completely randomized block, with 6 treatments and 4 replications. Treatments consisted of the combinations of doses (25% and 50% of the recommended complete dose for the lettuce) and application ofcomplete dose (100%) of phosphorus (P) and potassium (K) applied via fertirrigation, and a control (conventional fertilization system). The results showed that P and K availability in soil and nutrient concentration in plants were affected by treatments. Low phosphorus and potassium doses, applied via fertirrigation, were not efficient for the appropriate development of lettuce plants. The results showed that agronomic characteristics and commercial lettuce were affected by doses and application systems, especially the treatment with application of P and K full dose fertirrigation.

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A set of 12 samples of acid rock types Palmas (ATP) and Chapecó (ATC) was used to determine the chemical composition of plagioclase and pyroxene by electron microprobe, with the purpose to get information about the pressure and temperature of crystallization of these rocks. The results show that the pyroxene of ATP rocks (3,2 ± 1,2 kbar, max = 5,1 kbar and 1028 ± 38°C) were formed under pressure conditions higher than those ATC (1,8 ± 0,9 kbar, max = 3,4 kbar and 995 ± 26oC). However, the pressures obtained from plagioclase showed higher pressures for ATC (3.2 ± 1 kbar, max = 6,4 kbar and 1033 ± 12°C) than ATP (1,9 ± 1 kbar, max = 4,8 kbar and 1043 ± 5°C), suggesting that the crystallization of rocktype ATP began with the formation of pyroxene and plagioclase almost simultaneously at a depth of around 17 km while the ATC, began with the crystallization of plagioclase at a depth of about 21 km (assuming a gradient of 3,3 kbar/km). The geothermometry of plagioclase allow us to calculate the concentration of water from about 1 ± 0,3% H2O for both acid rock types. Additional calculations allow us to get the depth of water exsolution of magmatic liquid at 30m below the surface. Although the data are still preliminary and insufficient to model the extrusion of these rocks, they point out to an effusion mechanism of a partially fluidized magma by volatile, which would spread to large areas with small friction with the surface that would increased with the increase of viscosity caused by the loss of volatile and decreasing of temperature, developing coherent structures as lava flows.

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This study aimed to evaluate the effect of simulated chewing in the laboratory on the survival of seeds of four tropical forage legumes (butterfly pea, Clitorea ternatea; estilosantes, Stylosanthes capitata/S. macrocephala 'Campo Grande; archer, Macrotyloma axillare and perennial soybean, Neonotonia wightii) submitted to different periods of acid enzymatic digestion in vitro. Three trials were conducted to observe the percentage of destroyed seeds by the mastication; to compare the germination of the seeds (intact seeds, simulated mastication, scarification with sandpaper, mastication and scarification with sandpaper). And, finally the seeds were incubated at 39oC with hydrochloric acid and pepsin for: 0, 2, 4, 8, 12 and 24 hours. The percentages of not destroyed seeds in mastication (archer, 91,5; perennial soybean, 88.0; butterfly pea, 82.1, and estilo, 81.1), associated with the beneficial effects of scarification on germination (64.7, 60.0, 92.0 e 87.3%, respectively) and the effects of time of acid-enzymatic digestion (75% higher if they stay 24 hours in HCl + pepsin) associated to the hard and not permeable coats of legume seeds, allow a high potential for resistance, and to pass intact through the digestive tract of cattle, being able to germinate when defecated in the pastures. However, estilo should not be included in the feeding of cattle for this purpose, because it do not resists the acid-enzyme digestion.