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991.
992.
Marcelo Ribeiro Vilela Prado Oscarlina Lúcia dos Santos Weber Milton Ferreira de Moraes Carlos Leandro Rodrigues dos Santos Morgana Santos Tunes Fabricio Tomaz Ramos 《Communications in Soil Science and Plant Analysis》2016,47(21):2405-2413
Hypothetically, humic substances (HSs) can improve the response of plants in sandy soils. The objective was to assess the effect of applying an organomineral fertilizer enriched with HSs on soybean plants grown with and without water stress. The experimental design was entirely randomized, in a greenhouse, in a 2 × 5 factorial setup (two moisture levels and five fertilizer doses: 0, 1, 2, 4, and 8 mL dm?3), for a total of 10 treatments, with eight repetitions, using as substrate a Psamment. The organomineral fertilizer was applied in the soil 21 days after plant emergence, and the water regimes were established 1 week thereafter. Plant height, shoot and root dry mass, mineral nutrition, and grain yield were evaluated. There was a positive response to the doses, with the most efficient one under water stress being 6.5 mL dm?3 and HSs favored the uptake of micronutrients. 相似文献
993.
Ariadne Missono Brondi Josiane Souza Pereira Daniel Vitor Xavier Monteiro de Castro Jerusa Simone Garcia Marcello Garcia Trevisan 《Communications in Soil Science and Plant Analysis》2016,47(22):2506-2513
Humic substances are the main responsible for soil conditioning and are one of the major components of the composting product. However, there is still little information about their composition and mechanisms of activity. This study aimed to evaluate quantitatively the humic and fulvic fraction by size-exclusion liquid chromatography and the metal content by atomic absorption spectrometry. The chromatographic method used was efficient for humic and fulvic acids quantitation. Levels of 1.73 ± 0.03 and 1.6 ± 0.5 g kg?1 were found for chicken manure regarding humic and fulvic acids, respectively, and 5.1 ± 0.9 and 1.2 ± 0.1 g kg?1 for peat. The metal contents indicated the need of a mineral enrichment, because only the levels of iron reached the minimum recommended by legislation. It was also observed that evaluated organic fertilizers were in accordance with the specifications established by legislation in relation to carbon and total nitrogen and the pathogen levels. 相似文献
994.
Marta Simone Mendonça Freitas Monique Carriello Gama Pedro Henrique Monnerat Almy Junior Cordeiro De Carvalho Thaísa Capato Lima Ivo José Curcino Vieira 《Journal of plant nutrition》2016,39(6):835-841
Plants are key sources to obtain drugs and related medical compounds. In the species Catharanthus roseus L.G. Don, ordinarily known as vinca, contains significant amounts of the alkaloid ajmalicine, which is used as an anti-hypertension drug. The aim of this research was to verify the effect of macro-nutrient deficiencies and boron over ajmalicine bioproduction in vinca roots. The experiment was performed in random blocks with eight treatments: complete, nitrogen deficient (-N), phosphorus deficient (-P), potassium deficient (-K), calcium deficient (-Ca), magnesium deficient (- Mg), sulfur deficient (-S) and boron deficient (-B), with four replicates. Seedlings were initially watered once a day with a complete solution and after 55 days after germination the treatments were started. Plants were collected 135 days after germination and evaluated in relation to root's dry matter, concentration of N, P, K, Ca, Mg, S, B and ajmalicine. Concentration of N, P, K, Ca, Mg, S and B within the root's dry matter of the vinca plants in deficient treatments were respectively of 62, 61, 93, 52, 70, 61 and 44% lower when compared with complete treatment. Potassium deficiency resulted in ajmalicine increment of 19% within roots, while deficiencies in N, P, Mg and S reduced ajmalicine concentration in 55, 33, 22 and 26% respectively when compared with complete treatment. Deficiencies in Ca and B had no significant effect in ajmalicine concentration within the plant roots. Within plants with the complete treatment, nutrient contents of ajmalicine from the roots’ dry matter were respectively of 18,5 g kg?1 N, 1,46 g kg?1 P, 13,5 g kg?1 K, 4,47 g kg?1 Ca, 1,43 g kg?1 Mg, 1,53 g kg?1 S, 61 mg kg?1 B and 1,28 mg g?1 of vitexin. 相似文献
995.
M P Arala-Chaves A dos S Ribeiro M Vilanova M T Porto M G Santarem M Lima 《American journal of veterinary research》1988,49(11):1955-1961
Virus-free supernatants of cultured swine monocytes infected by African swine fever virus (ASFV) suppressed in vitro proliferation of porcine and human blood mononuclear cells in response to phytohemagglutinin and the in vivo primary immune response of C57BL/6 mice against sheep RBC. The supernatants were fractionated by discontinuous ion-exchange chromatography and subfractionated by double-step preparative isoelectric focusing. The pool of the most purified active subfractions (F5'EP-ASFV) is made up of heat-unstable material, can be stained by silver nitrate, and has an isoelectric point of 3.88, a maximal optical density at 280 nm, and a mass of 36,000 daltons. In vivo kinetic studies in nonimmunized C57BL/6 mice were performed on days 1, 2, 3, 5, and 7 after injection with 50 micrograms of F5'EP-ASFV protein. Compared with the untreated mice, the treated mice had a noticeable increase in nonspecific immunoglobulin-secreting splenic plaque-forming cells (PFC) with the following isotype profile: IgG2a greater than IgG2b greater than IgG3 greater than IgG1 congruent to IgM. Three days after treatment with the active material, specific IgM PFC against sheep RBC increased up to 23-fold. In C57BL/6 mice immunized against sheep RBC 2 days after treatment with F5'EP-ASFV, the increase in nonspecific PFC was followed by a suppression of specific PFC response in the respective isotype. When C57BL/6 mice were treated after priming with sheep RBC, however, there was little or no suppression of specific PFC and the increase in nonspecific PFC was considerably lower than that in the other F5'EP-ASFV-treated mice. In this case, kinetic curves of specific vs nonspecific PFC of each isotype were mirror images. Mice treated with 200 micrograms of F5'EP-ASFV protein died with hemorrhagic diastasis. 相似文献
996.
Ribeiro MG Seki I Yasuoka K Kakuda T Sasaki Y Tsubaki S Takai S 《Comparative immunology, microbiology and infectious diseases》2005,28(1):53-61
We investigated the prevalence of virulent Rhodococcus equi in clinical isolates from 41 foals (19 sporadic and seven endemic cases) in Brazil between 1991 and 2003. Of the 41 virulent isolates, six contained an 85-kb type I plasmid, 33 contained an 87-kb type I plasmid, both of which have been found in isolates from the Americas, and the remaining two contained a new variant, which did not display the EcoRI, EcoT22I and BamHI digestion patterns of the 11 representative plasmids already reported (85-kb types I-IV; 87-kb types I and II; 90-kb types I-V). We tentatively designated the new variant as the '87-kb type III' plasmid, because its BamHI digestion pattern is similar to that of the 87-kb type I plasmid. This is the first report of the molecular epidemiology surveillance of virulent R. equi in clinical isolates from Brazilian foals. 相似文献
997.
Raila J Forterre S Schweigert FJ 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(5-6):229-239
The term proteinuria is taken to mean abnormally high protein excretion in the urine. Proteinuria is the consequence of glomerular filtration of plasma proteins, their subsequent reabsorption by the proximal tubular cells and secretion of protein by the tubular cells and distal urinary tract. In physiological conditions, the structural integry of the glomerular filtration barrier prevents the abnormal passage of albumin (molecular mass 66 kDa) and high-molecular-weight proteins (> 66 kDa), whereas the passage of low-molecular-weight proteins (< 66 kDa) is almost completely unrestricted. Proteins that arrive the tubular lumen are reabsorbed by endocytosis after binding to the megalin-cubilin complex. An increased load of proteins in the tubular lumen leads to the saturation of the reabsorptive mechanism and higher urinary protein excretion. Proteinuria can originate from prerenal, renal and postrenal causes. Elevated tubular protein concentrations have been recognized to be toxic to tubular cells and associated with the progression of chronic renal disease. Therefore, the quantitative and qualitative evaluation of proteinuria is important for the diagnosis of renal disease. 相似文献
998.
Orsi AM Stefanini MA Crocci AJ Simões K Ribeiro AA 《Anatomia, histologia, embryologia》2004,33(3):131-134
Structural features of segmental parts of the aorta of the dog were studied by light microscopy (LM) and scanning electron microscopy (SEM). The variability in the wall architecture composition and vascular thickness of the ascending (T2-3 level), thoracic (T7-8 level) and abdominal (L6-7 infrarenal level) segments of the aorta was analysed. Morphological features such as presence of intimal folds, pattern of the medial myoconnective components with segmental variations in the number of elastic lamellae, whose relative number was higher in the thoracic aorta (ascending and descending parts), compared with the abdominal aorta, and a network of connective (stromal) elements formed by elastic and collagen lamellae and fibres in the adventitia were observed. The results were discussed on a histophysiological basis, because small but significant segmental differences had been characterized in the aortic wall structure of the dog. 相似文献
999.
The present study investigated the ultrastructural features of the basilar artery of the largest rodent species, the capybara. The study suggests that the general ultrastructural morphological organization of the basilar artery of the capybara is similar to that of small rodents. However, there are some exceptions. The basilar artery of the capybara contains a subpopulation of 'granular' vascular smooth muscle cells resembling monocytes and/or macrophages. The possibility cannot be excluded that the presence of these cells reflects the remodelling processes of the artery due to animal maturation and the regression of the internal carotid artery. To clarify this issue, more systemic studies are required involving capybaras of various ages. 相似文献
1000.
Corneal esthesiometry in the healthy horse 总被引:1,自引:1,他引:0
Objective To determine corneal sensitivity in healthy adult horses in order to establish reference values. Animals studied One hundred eyes of 50 healthy adult horses. Procedure Corneal sensitivity was determined by evaluating the corneal touch threshold (CTT) in five different corneal regions using a Cochet‐Bonnet esthesiometer. Results Comparing CTT values (in mm filament length) of the five prescribed corneal regions revealed regional variations in corneal sensitivity, with the central region (21.15 ± 6.23 mm) being the most sensitive, followed by the nasal (20.75 ± 5.14 mm), temporal (20.70 ± 5.37 mm), ventral (20.15 ± 5.88 mm) and dorsal (15.85 ± 3.70 mm) region. However, differences between the central, nasal, temporal and ventral regions were not statistically significant, whereas the dorsal region was significantly (P < 0.0001) less sensitive compared to the other regions. Division of the horses into three age groups revealed an insignificant decrease in corneal sensitivity with age in the nasal, temporal, ventral and central region, and an insignificant increase with age in the dorsal region. Correlation of corneal sensitivity with age was statistically significant in the central, ventral and temporal region. No statistically significant difference in the CTT was found between left and right eyes and between males and females. Conclusions CTT values in 100 eyes of 50 healthy adult horses evaluated with a Cochet‐Bonnet esthesiometer generated reference values. Reference values are necessary to determine alterations of corneal sensation accompanying various eye diseases or systemic diseases. 相似文献