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991.
992.
P I Punch N D Costa E D Chambers D H Slatter G E Wilcox 《Research in veterinary science》1985,39(2):179-187
Chloramphenicol, erythromycin, gentamicin, oxytetracycline, penethamate and procaine benzyl penicillin were administered parenterally to cattle and the concentrations of these antibiotics in plasma and tears were assayed microbiologically. Concentrations in plasma and tears were significantly correlated for all antibiotics tested but the concentration of antibiotic in tears and the tear flow rate were not correlated. Lipophilic drugs diffused into the tears in higher concentrations than did drugs which were not lipophilic. Concentrations of lipophilic but not hydrophilic antibiotics in tears could be predicted from the Henderson-Hasselbach equation. In cattle, it is possible through parenteral administration of chloramphenicol, erythromycin, gentamicin or oxytetracycline to achieve antibiotic concentrations in the tears which are bacteriostatic to Moraxella bovis, a primary aetiological agent of infectious bovine keratoconjunctivitis. 相似文献
993.
Denilson F. Oliveira Vicente P. Campos Daniel R. Amaral Alexandro S. Nunes José A. Pantaleão Deivid A. Costa 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(4):477-479
This work aimed to select potentially useful rhizobacteria for the control of Meloidogyne exigua, a widely disseminated root-knot nematode found in Brazilian coffee fields. Initially, crude metabolites produced in liquid
medium by 69 isolated rhizobacteria strains (previously obtained from several plants collected in the south of Minas Gerais
State, Brazil) were tested in vitro for lethality towards M. exigua second stage juveniles (J2). Substances produced by strains of Bacillus cereus, B. megaterium, B. pumilus, B. thuringiensis, Enterobacter asburiae, E. cloacae and Paenibacillus macerans caused high mortality in J2. Subsequently, the ten most active crude metabolites were selected and assessed for nematicidal activity in a biotest with
M. exigua-inoculated coffee plants. Although strains of B. cereus, B. pumilus and P. macerans caused a significant reduction in the number of root galls and/or nematode eggs per plant 90 days after treatment, the best
results were obtained with the application of B. megaterium strain 54-06. 相似文献
994.
E. G. Moura N. G. Moura E. S. Marques K. M. Pinheiro J. R. S. Costa Sobrinho A. C. F. Aguiar 《Soil Use and Management》2009,25(4):368-375
In tropical regions with well‐defined wet and dry seasons, repeated wetting and drying cycles can harden exposed soils and inhibit root growth. While this phenomenon has been well documented, the relationships between plant productivity and chemical and physical soil parameters have not been well defined. The current study identifies the abiotic parameters that best relate to measures of plant development, specifically to corn productivity. The primary goal of this research was to provide information to improve agricultural sustainability in humid tropical ecosystems. The effects of using plant residues as a cover on a sandy soil were studied. Four leguminous species were planted in an alley cropping system, Leucaena leucocephala, Cajanus cajan, Clitoria fairchildiana and Acacia mangium, and corn was planted in January 2007 between legume rows. We measured the most important chemical and physical soil parameters. Yield indicators included cob weight and the weight of 100 kernels. The application of plant residues altered soil conditions and increased rootable soil volume. This change was associated with an increase by 10% in water retention above field capacity in the uppermost soil layer of the residue‐covered sections of the experiment. In the control sections cobs were up to three times lighter (31.43–93.38 g) in the bare soil control than those from residue‐covered sections of the experiment. Dynamic indicators related to nutrient absorption and crop evapotranspiration, such as the number of days with water stress and rootable soil volume, were the most suitable indicators for assessing soil quality. The response of corn was best related to complex physical indicators, including the amount of N applied via legume residues. 相似文献
995.
Abstract. The application of gypsum to a Natraquoll under pasture was evaluated in a humid area of the 'Flooding Pampas' of Argentina in a randomized block field design. Gypsum was incorporated at 0, 15, 35, and 60 t ha-1 . After the gypsum was mixed into the soil, the electrical conductivity of the soil solution was linearly related to the initial sodium adsorption ratio. The depth of reclamation depended on the amount of gypsum applied. Dry matter yield in all gypsum treatments was greater than the control without gypsum. 相似文献
996.
Water, Air, & Soil Pollution - In Brazil’s littoral, many iron ore industries are located in areas of restinga, a type of coastal ecosystem; such industries represent stationary sources... 相似文献
997.
998.
Elisabete da Costa Tnia Melo Mariana Reis Pedro Domingues Ricardo Calado Maria Helena Abreu Maria Rosrio Domingues 《Marine drugs》2021,19(8)
Grateloupia turuturu Yamada, 1941, is a red seaweed widely used for food in Japan and Korea which was recorded on the Atlantic Coast of Europe about twenty years ago. This seaweed presents eicosapentaenoic acid (EPA) and other polyunsaturated fatty acids (PUFAs) in its lipid fraction, a feature that sparked the interest on its potential applications. In seaweeds, PUFAs are mostly esterified to polar lipids, emerging as healthy phytochemicals. However, to date, these biomolecules are still unknown for G. turuturu. The present work aimed to identify the polar lipid profile of G. turuturu, using modern lipidomics approaches based on high performance liquid chromatography coupled to high resolution mass spectrometry (LC–MS) and gas chromatography coupled to mass spectrometry (GC–MS). The health benefits of polar lipids were identified by health lipid indices and the assessment of antioxidant and anti-inflammatory activities. The polar lipids profile identified from G. turuturu included 205 lipid species distributed over glycolipids, phospholipids, betaine lipids and phosphosphingolipids, which featured a high number of lipid species with EPA and PUFAs. The nutritional value of G. turuturu has been shown by its protein content, fatty acyl composition and health lipid indices, thus confirming G. turuturu as an alternative source of protein and lipids. Some of the lipid species assigned were associated to biological activity, as polar lipid extracts showed antioxidant activity evidenced by free radical scavenging potential for the 2,2′-azino-bis-3-ethyl benzothiazoline-6-sulfonic acid (ABTS●+) radical (IC50 ca. 130.4 μg mL−1) and for the 2,2-diphenyl-1-picrylhydrazyl (DPPH●) radical (IC25 ca. 129.1 μg mL−1) and anti-inflammatory activity by inhibition of the COX-2 enzyme (IC50 ca. 33 µg mL−1). Both antioxidant and anti-inflammatory activities were detected using a low concentration of extracts. This integrative approach contributes to increase the knowledge of G. turuturu as a species capable of providing nutrients and bioactive molecules with potential applications in the nutraceutical, pharmaceutical and cosmeceutical industries. 相似文献
999.
Yasmmin Tadeu Costa Nilton Curi Geraldo César de Oliveira Luiz Roberto Guimarães Guilherme 《Communications in Soil Science and Plant Analysis》2019,50(6):673-681
Many factors can influence the results obtained by portable X-ray fluorescence analysis (pXRF). The effect of soil organic matter on pXRF results is not satisfactory understood. Thus, we conducted this study to verify the effect of organic matter removal on oxide determination by pXRF in Oxisols. To obtain soil material with different organic matter contents and maintaining the same elemental composition from soil minerals, six contrasting Oxisols were heated in a muffle furnace for 30 min at the following temperatures (°C): 100; 200; 300; 400; 500 and 600. After heating, the soil samples were scanned using a pXRF Bruker® S1 Titan LE model (Dual Soil mode) for 60 s and the contents of SiO2, Al2O3, Fe2O3, TiO2, P2O5, and MnO were recorded. The soil organic matter presence underestimated the pXRF results for lightest oxides (Si and Al) compared to heaviest oxides (Fe, Ti, and Mn). These oxides are important for tropical soils classification and for many soil-related studies and pXRF technology has been a useful tool for soil chemical characterization. Our findings contribute to more suitable use of pXRF highlighting the possible effect of organic matter. 相似文献
1000.
Rubens Ribeiro Silva Alvaro José Gomes Faria Adriana Augusta Neto Tayna Alves Pereira Jaci De Souza Dias Antônio Carlos Martins Santos 《Communications in Soil Science and Plant Analysis》2019,50(10):1267-1277
The aim of this work was to evaluate the effect of phosphorus (P) levels on nodulation and soybean production components in Cerrado soils. The experimental design was randomized in blocks, with five replicates, and four consecutive crop seasons (2013/2014, 2014/2015, 2015/2016, and 2016/2017), being cultivated in the same experimental field area. In the first three crop seasons phosphate fertilization were carried out establishing the treatments of increasing levels of P: 0, 43.6, 87.3, 131.0, and 174.6 kg ha?1, and an additional level (farm standard) of 42 kg ha?1. The results of this work refer to the crop season 2016/2017 without different P application, evaluating the influence of content of previous crop seasons. The dry weight of roots, plant population, thousand grains weight, grain yield, nitrogen (N) and P content in leaves, number and dry weight of nodules were evaluated in the reproductive stages (R2 and R8) of soybean. Increasing levels of P in soil provided significant effects on nodulation, morphological components and production of soybean plants. Levels above 40 mg dm?3 of P available in soil provided a reduction in the number and dry weight of the nodules that are highly correlated to reduction on grain yield. 相似文献