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51.
Bruna de Campos Ventura 《Pesticide biochemistry and physiology》2008,90(1):42-51
Atrazine is the triazinic herbicide most found in the rural aquatic environments due to its extensive use and its stability in such places. The mutagenicity and the genotoxicity of different concentrations of the Atrazine herbicide were determinated by the micronucleus test and the comet assay, using Oreochromis niloticus as test-system. The tested concentrations of Atrazine herbicide were 6.25, 12.5 and 25 μg/L, both for the micronuclei test and for the comet assay. The results showed a significant rate of micronuclei and nuclear abnormalities for all the tested concentrations of Atrazine herbicide. For the comet assay, we also observed results significantly different from the control in 6.25, 12.5 and 25 μg/L concentrations. Due to these results, we could infer that such herbicide may be dangerous to the lives of those organisms exposed to it. 相似文献
52.
Walda Monteiro Faria Thais Rodrigues Coser Ailton Teixeira Vale Bruna Gehrke Schneider 《Archives of Agronomy and Soil Science》2018,64(4):505-519
Sewage sludge (SS) is a by-product of wastewater treatment resulting from human and industrial activities. This waste is problematic because it is difficult to manage due to its volume and environmental impacts; therefore, new technologies for treatment are needed to make its final disposal feasible. Such technologies include the pyrolysis process that produces biochar, which can be used for agricultural purposes. The present study reports a two-year field experiment with SS biochar produced under different pyrolysis temperatures and its application to soil in combination with mineral fertilizer to evaluate its effect on soil chemical properties and on corn nutrition and yield. To conduct this evaluation, 15 Mg ha?1 of SS biochar combined or not with mineral fertilizer (NPK) was applied to the soil in the 2015 and 2016 cropping seasons. SS biochar increased soil chemical attributes, especially phosphorus, magnesium, cation exchange capacity and base saturation. Biochar resulted in a greater absorption of nutrients by plants and higher corn yields. However, SS biochar alone was incapable of increasing K uptake by corn. It was concluded that the application of SS biochar can replace mineral fertilizers (nitrogen, phosphorus and micronutrients) for corn production. 相似文献
53.
Barros L Venturini BA Baptista P Estevinho LM Ferreira IC 《Journal of agricultural and food chemistry》2008,56(10):3856-3862
The chemical composition and biological properties of Portuguese wild mushrooms ( Cantharellus cibarius, Hypholoma fasciculare, Lepista nuda, Lycoperdon molle, Lycoperdon perlatum, Ramaria botrytis, Tricholoma acerbum) were evaluated in order to assess these products as sources of nutrients and nutraceuticals. The analyzed mushrooms contain very useful phytochemicals such as phenolics, tocopherols, ascorbic acid, and carotenoids. All of the species proved to have antioxidant activity (measured by four different methods), being more significant for R. botrytis (EC 50 values < 1 mg/mL). Lycoperdon species were resistant to all of the tested microorganisms, and the other samples revealed antimicrobial activity selectively against Gram-positive bacteria, with very low minimal inhibitory concentration, in some cases, even lower than the standard. The combination of bioactive compounds and rich nutritional composition (high contents in protein and carbohydrates, low content in fat with the precious contribution of unsaturated fatty acids and the absence of trans fatty acids) in the mushroom makes it a very special food. 相似文献
54.
Erika M. Nakazono Emilio M. Bruna Rita C. G. Mesquita 《Forest Ecology and Management》2004,190(2-3):219-225
The harvesting of non-timber forest products has been proposed as an alternative to timber harvesting that can increase rural income while having a reduced impact on forest structure. However, surprisingly little is known about the biological consequences of harvesting these products. We conducted a 3-year experiment in which we simulated the stem harvesting of the Amazonian plant Ischnosiphon polyphyllus, which is used by traditional and indigenous populations in the Amazon for the construction of baskets, mats, and other handicrafts used in manioc cultivation. We found that plant mortality is limited in all except the most extreme harvesting treatments. However, we also found that plants recuperate extremely slowly from experimental harvesting. These results suggest that current harvesting strategies may not be conservative enough to ensure long-term population survival. 相似文献
55.
Rebeca Scalco DVM Monica Aleman MVZ Cert PhD DACVIM Carlos E. W. Nogueira DVM MSc PhD Natalia B. Freitas DVM Bruna R. Curcio DVM MSc PhD 《Journal of Veterinary Emergency and Critical Care》2023,33(2):217-222
Objectives
To report red cell distribution width (RDW) values, to calculate RDW-to-platelet ratio (RPR), and to investigate a possible correlation of RDW and RPR index values in neonatal foals classified as healthy or at risk based on clinical information from a population of foals up to 24 hours of life.Design
Retrospective study conducted from records and CBCs of foals born between June and November from 2018 to 2020 foaling seasons.Setting
Breeding farm.Animals
Three hundred and nine neonatal full-term Thoroughbred foals.Interventions
None.Measurements and Main Results
Foals were evaluated by a veterinarian within 15 minutes after birth, and a blood sample was collected within 24 hours of life. Based on clinical information, 88 of 309 foals (28.4%) were considered at risk of perinatal disease, and 201 were healthy. Mean gestational age for the foals was 346.3 ± 9.7 days. RDW values did not differ between groups. Gestational length demonstrated to have a negative correlation with RDW (r = –0.156, P = 0.005) and mean corpuscular volume (r = –0.135, P = 0.01), indicating a link of these variables to foal maturity. RPR index was higher for at-risk (0.073 ± 0.018) than for healthy foals (0.068 ± 0.014, P = 0.01).Conclusion
RPR might be a promising early indicator of disease for the field triage of neonatal foals. 相似文献56.
Alane P. O. Monte Jamile M. Santos Vanúzia G. Menezes Bruna B. Gouveia Thae L. B. G. Lins Ricssio S. Barberino Joozito L. Oliveira Nathalie J. Donfack Maria Helena T. Matos 《Reproduction in domestic animals》2019,54(9):1169-1176
This study analysed the effect of growth differentiation factor‐9 (GDF‐9) on the in vitro culture of isolated ovine secondary follicles. The follicles were cultured in α‐MEM supplemented with BSA, insulin, glutamine, hypoxanthine, transferrin, selenium, ascorbic acid and FSH (α‐MEM+—control medium) or α‐MEM+ supplemented with 1, 10, 50 or 100 ng/ml GDF‐9. Next, the oocytes were destined to in vitro maturation (IVM). After 12 days of culture, there were no differences regarding the percentage of normal follicles, antrum formation and follicle diameter between the treatments (p > 0.05). The rates of fully grown oocytes (≥110 µm) were higher (p < 0.05) in 100 ng/ml GDF‐9 than other treatments, except for 10 ng/ml of GDF‐9 (p > 0.05). Treatment containing 100 ng/ml GDF‐9 showed higher (p < 0.05) mitochondrial activity than the control group. Moreover, 100 ng/ml GDF‐9 showed more oocytes in MI than α‐MEM+, 1 or 50 ng/ml GDF‐9 (p < 0.05). In conclusion, 100 ng/ml GDF‐9 increased the growth, mitochondrial function and meiotic resumption of oocytes from in vitro grown sheep secondary follicles. 相似文献
57.
Global mitochondrial DNA (mtDNA) methylation has been recently described in bovine and showed particular signatures in both gametes and embryos. Here, we investigated the distribution of mtDNA methylation through strand-specific mapping of methylation sites to gain perspective on how epigenetic mechanisms can be involved in mitochondrial function. We demonstrate that in both oocytes and embryos, the frequency of methylation is biased towards the light strand (L-strand), particularly in the gene bodies and in the region containing the L-strand promoter (LSP). Methylation is not restricted to CpG nucleotides and is not symmetrical on both strands. This configuration reinforces the hypothesis of a specific epigenetic regulation of mtDNA, which is an important observation for the understanding of how mitochondrial function is regulated. 相似文献
58.
Comparison of equine bone marrow-, umbilical cord matrix and amniotic fluid-derived progenitor cells
Lovati AB Corradetti B Lange Consiglio A Recordati C Bonacina E Bizzaro D Cremonesi F 《Veterinary research communications》2011,35(2):103-121
The aim of the study was to compare in vitro the stemness features of horse progenitor cells derived from bone marrow (BM-MSCs),
amniotic fluid (AF-MSCs) and umbilical cord matrix (EUC-MSCs). It has been suggested that there may be a stem cell population
within both umbilical cord matrix and amniotic fluid. However, little knowledge exists about the characteristics of these
progenitor cells within these sources in the equine species. This study wanted to investigate an alternative and non-invasive
stem cell source for the equine tissue engineering and to learn more about the properties of these cells for future cell banking.
Bone marrow, umbilical cord and amniotic fluid samples were harvested from different horses. Cells were analyzed for proliferation,
immunocytochemical, stem cell gene expression and multilineage plasticity. BM- and AF-MSCs took similar time to reach confluence
and showed comparable plating efficiency. All cell lines expressed identical stem cell markers and capability to differentiate
towards osteogenic lineage. Almost all cell lines differentiated into the adipogenic lineage as demonstrated by cytochemical
staining, even if no adipose gene expression was detectable for AF-MSCs. AF- and EUC-MSCs showed a limited chondrogenic differentiation
compared with BM-MSCs as demonstrated by histological and biochemical analyses. These findings suggest that AF-MSCs appeared
to be a readily obtainable and highly proliferative cell line from an uninvasive source that may represent a good model system
for stem cell biology. More studies are needed to investigate their multilineage potential. EUC-MSCs need to be further investigated
regarding their particular behavior in vitro represented by spheroid formation. 相似文献
59.
Heckenberger MJ Kuikuro A Kuikuro UT Russell JC Schmidt M Fausto C Franchetto B 《Science (New York, N.Y.)》2003,301(5640):1710-1714
Archaeology and indigenous history of Native Amazonian peoples in the Upper Xingu region of Brazil reveal unexpectedly complex regional settlement patterns and large-scale transformations of local landscapes over the past millennium. Mapping and excavation of archaeological structures document pronounced human-induced alteration of the forest cover, particularly in relation to large, dense late-prehistoric settlements (circa 1200 to 1600 A.D.). The findings contribute to debates on human carrying capacity, population size and settlement patterns, anthropogenic impacts on the environment, and the importance of indigenous knowledge, as well as contributing to the pride of place of the native peoples in this part of the Amazon. 相似文献
60.
Kelsey M Schubach Reinaldo F Cooke Courtney L Daigle Alice P Brando Bruna Rett Vitor S M Ferreira Giovanna N Scatolin Eduardo A Colombo Genevieve M DSouza Ky G Pohler Bruno I Cappellozza 《Journal of animal science》2020,98(9)
This experiment evaluated the impacts of administering a bovine appeasing substance (BAS) to beef calves at weaning on their performance, physiological responses, and behavior during a 42-d preconditioning program. Eighty calves (40 heifers and 40 steers; 90% British × 10% Nellore) were weaned at 233 ± 2 d of age (day 0); ranked by sex, weaning age, and body weight (BW); and assigned to receive BAS (IRSEA Group, Quartier Salignan, France; n = 40) or placebo (diethylene glycol monoethyl ether; CON; n = 40). Treatments (5 mL) were topically applied to the nuchal skin area of each animal following dam separation. Within treatment, calves were allocated to one of eight drylot pens (four pens per treatment; pen being the experimental unit) and received a free-choice total mixed ration (TMR) from day 0 to 42, intake of which was assessed daily. Live behavior observations were conducted on days 1, 2, 4, 8, 16, and 32. Temperament was assessed and blood samples were collected via jugular venipuncture on days −21, 0, 3, 7, 14, 28, and 42. Hair samples were collected from the tail switch on days 0, 14, 28, and 42. Calves were vaccinated against bovine respiratory disease viruses on days −21 and 0. Average daily gain from day 0 to 42 did not differ between treatments (P = 0.57) but was greater (P = 0.05) in BAS vs. CON calves from day 0 to 28. Intake of TMR was greater (P = 0.05) during the first week for BAS vs. CON calves (treatment × week; P = 0.08). The mean proportion of calves feeding simultaneously and performance of social and play behaviors were greater (P ≤ 0.05) for BAS vs. CON calves. Escape attempts were greater (P < 0.01) for BAS vs. CON calves on day 1 (treatment × day; P = 0.03). Exit velocity was greater (P = 0.04) for CON vs. BAS calves on day 14 and tended (P = 0.10) to be greater for CON vs. BAS calves on day 7 (treatment × day; P = 0.03). Mean plasma concentrations of haptoglobin were greater (P = 0.02) in CON vs. BAS calves. Hair cortisol concentrations were greater (P = 0.05) in CON vs. BAS calves on day 14 (treatment × day; P = 0.03). Mean serum concentrations of antibodies against bovine viral diarrhea virus were greater (P = 0.02) in BAS vs. CON calves. Collectively, BAS administration to beef calves at weaning alleviated stress-induced physiological reactions, improved temperament evaluated via chute exit velocity, enhanced humoral immunity acquired from vaccination, and appeared to have accelerated adaptation to novel management scheme and environment. 相似文献