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61.
L.M.F. Lucinda B.J. Vieira T.T. Oliveira R.C.S. S V.M. Peters J.E.P. Reis M.O. Guerra 《Fitoterapia》2010,81(8):982-987
This study was aimed at investigating the anti-osteoporotic effects of the extract of Ginkgo biloba (EGb) in glucocorticoid-induced-osteoporosis. A significant reduction was observed in the percentage of the bone of the osteoporosis group in both the mandible and femur. The EGb group treated with 28 and 56 mg/Kg showed a significant increase in the percentage of trabecular bone (PTB) of the femur. The percentage of the alveolar bone of the mandible (PAB) had a significant increase with all doses of EGb. The treatment with EGb significantly reversed the loss of the PAB of the mandible and of the PTB of the femur. 相似文献
62.
Impact and effects of paralytic shellfish poisoning toxins derived from harmful algal blooms to marine fish 下载免费PDF全文
Pedro Reis Costa 《Fish and Fisheries》2016,17(1):226-248
Fish are frequently exposed to paralytic shellfish toxins (PSTs) derived from harmful algal blooms (HAB). PSTs are potent neurotoxins with strong effects on fish at multiple trophic levels. Here, we examine the historical and contemporary mass mortality events combining with the available data on response of fish to PSTs' exposure. The data show that fish are negatively affected by these natural toxins on a recurring basis. Transient effects of PSTs have also been observed in fish and although difficult to quantify, these sublethal effects can affect foraging and predation avoidance. Additionally, the spatiotemporal overlapping of fish spawning and HAB can also be critical for fish survival and fisheries recruitment. Exposure of fish in their early life stages to dissolved toxins in the water column has also been identified as a risk factor for fish survival. In the context of global climate change, where PSTs are likely to become increasingly important, new insights and a synthesis of up‐to‐date information on fish response to PSTs and the risk associated with toxic dinoflagellate blooms are presented. 相似文献
63.
Flávio Martins Santana Cesar Bauer Gomes Cesar Rombaldi Valmor João Bianchi Ailton Reis 《Phytoparasitica》2013,41(5):557-568
The populations of Phytophthora infestans (Pi) in southern Brazil in 2004 and 2005 are characterized herein. The isolates were collected from potato and tomato plants in the states of Paraná (PR), Santa Catarina (SC), and Rio Grande do Sul (RS). The mating type of 131 potato and 32 tomato isolates was determined. Forty-nine isolates from potatoes and 11 from tomatoes were analyzed for their Gpi phenotype. A subset of 35 isolates was evaluated for mitochondrial (mtDNA) polymorphisms. A sample of 146 isolates was tested for sensitivity to the fungicide metalaxyl, and most isolates (64%) were moderately sensitive. Fifty-nine isolates were classified as A1 mating type and 103 as A2. One isolate behaved as both A1 and A2 mating type. All tomato isolates were A1 mating type and presented the 86/100 pattern for the enzyme GPI and mtDNA Ib, indicating that these isolates belong to the US-1 clonal lineage. Of the 131 potato isolates, 103 were A2, 27 were A1 and one was A1/A2 mating type. Among the potato isolates 27 exhibited the Gpi phenotype 100/100, the same as BR-1, and 20 were 86/100, the same as US-1. Potato isolates presented the mitochondrial haplotypes Ia (74%) and IIa (26%). The data suggest the presence of only the BR-1 clonal lineage on potatoes in the states of PR and SC. However, in the state of RS, more than one clonal lineage was observed infecting potatoes, and there may be sexual reproduction between the lineages. 相似文献
64.
José Wilacildo de Matos Oliveiro Guerreiro-Filho Wallace Gon?alves Daniel Alves Ramiro Bárbhara Joana dos Reis Fatobene 《Euphytica》2011,181(2):253-260
The coffee leaf miner, Leucoptera coffeella, is the most important pest of Coffea arabica plantations in Brazil, and all cultivars are susceptible to the insect. However, distinct reactions have been observed in
other species, such as C. congensis and C. canephora. In this work, the occurrence of antixenotic response was surveyed in individuals of Coffea species, selected for resistance to the leaf miner at both field and laboratory conditions. Tests performed on young plants
from C. arabica cultivars Icatu Precoce IAC 3282, Mundo Novo IAC 515-20, Tupi IAC 1669-33 and Catuaí Amarelo IAC 62 demonstrated that these
were preferred for oviposition when pooled with seedlings from C. canephora cv. Apoat? IAC 2258. Apoat? was also preferred over C. racemosa for oviposition. Similar results were observed in tests using detached leaves, and higher amount of eggs was counted in the
cv Obat? IAC 1669-20 and Catuaí Vermelho IAC 81, and lower oviposition frequency was observed in C. canephora cv. Guarini IAC 1598. C. congensis showed an oviposition frequency between C. arabica and C. canephora. Also, the results suggest that the frequency of oviposition is co-related with the plant resistance level, during larvae
infection. 相似文献
65.
66.
Over the last few decades, many researchers have produced landslide susceptibility maps using different techniques including the probability method (frequency ratio), the analytical hierarchy process (AHP), bivariate, multivariate, logistics regression, fuzzy logic and artificial neural network In addition, a number of parameters such as lithology, slope, aspect, land cover, elevation, distance to stream, drainage density, distance to lineament, seismicity, and distance to road are recommended to analyze the mechanism of landslides. The data quality is a very important issue in landslide studies, and more accurate results will be achieved if the data is adequate, appropriate and drawn from a wide range of parameters. The aim of this study was to evaluate the susceptibility of the occurrence of landslides in Trabzon province, situated in north east Turkey. This was achieved using the following five methods the frequency ratio model, AHP, the statistical index (Wi), weighting factor (Wf) methods, and the logistics regression model, incorporating a Geographical Information System (GIS) and remote sensing techniques. In Trabzon province there has been an increasing occurrence of landslides triggered by rainfall. These landslides have resulted in death, significant injury, damage to property and local infrastructure and threat of further landslides continues. In order to reduce the effects of this phenomenon, it is necessary to scientifically assess the area susceptible to landslide. To achieve this, landslide susceptible areas were mapped the landslide occurrence parameters were analyzed using five different methods. The results of the five analyses were confirmed using the landslide activity map containing 50 active landslide zones. Then the methods giving more accurate results were determined. The validation process showed that the Wf method is better in prediction than the frequency ratio model, AHP, the statistical index (Wi), and logistics regression model. 相似文献
67.
Joana Reis Teresa Oliveira Alfredo Pereira Paulo Infante Nuno Leal Pedro Faísca 《Veterinary and comparative oncology》2020,18(3):281-291
The present work describes the microtomographic characterization of macro‐ and microcalcifications present in excised canine mammary glands. In human breast cancer, microcalcifications are highly relevant for diagnosis and prognosis, often being the sole element determining biopsy. Canine mammary tumours are considered a model for human breast cancer, but the morphological features of calcifications had still to be studied in this species. The objective of this research is to contribute to the characterization of the mineralization features of the canine mammary gland. In the present study, the excised mammary glands of 33 bitches underwent fluoroscopic examination. In 30 of the samples, the presence of calcification was suspected, and multiple biopsies were taken of these areas. Biopsy fragments underwent microtomographic scanning. Microcalcifications were found in non‐neoplastic glandular tissue, benign and malign lesions, as it is known to happen in humans. Qualitative evaluation regarding morphology of the imaged calcifications showed similarities to breast cancer findings, based on the BI‐RADS 2013 classification, such as pleomorphism and shape. No differences in the quantitative morphological parameters of volume, surface, surface/volume, SMI and structure thickness were found when macrocalcifications were considered. However, although significant differences existed in these parameters between microcalcifications from malignant canine mammary tumours and the two other groups, none were found between non‐neoplastic and benign tumours. Findings further support the use of this spontaneous animal model for the study of human breast cancer, considering how clinically relevant microcalcifications are in humans. 相似文献
68.
de Oliveira Wildiney Freire de Lima Elizanne Moura de Freitas Denise Ribeiro dos Santos Suely Sousa Reis Grazielle Carvalho Gomes Daiany Iris Alves Kaliandra Souza Maciel Raylon Pereira Vargas Julián Andrés Castillo Mezzomo Rafael 《Tropical animal health and production》2020,52(5):2379-2385
Tropical Animal Health and Production - We aimed to evaluate the chemical composition, production yield, and economic viability of Minas Frescal cheese produced with milk from buffaloes... 相似文献
69.
Andre Rodrigues dos Reis Jose Laercio Favarin Luiz Antonio Gallo Milton Ferreira Moraes Tiago Tezotto Dr Jose Lavres Junior 《Journal of plant nutrition》2013,36(12):1853-1866
Nutritional and physiological significance of micronutrients in coffee plants, especially with regard to nickel (Ni) is still unknown. The dynamics of nitrogen (N), phosphorus (P), potassium (K) and Ni accumulation in coffee fruits, as well as their relationships with total soluble protein, amino acids, reducing sugars, and starch content during coffee fruit development (green, ripe, and dry fruits), were investigated. Coffee trees received three N fertilizer rates (0, 150, and 300 kg of N ha?1) as ammonium sulfate split into three applications per year. Nitrogen fertilization increased reducing sugars and starch concentrations in ripe fruits. In contrast, green fruits showed the highest amino acid and Ni concentrations. Fruit Ni concentration decreased in both green and ripe fruits as N rates increased; thus, indicating the possibility of either a N-associated dilution effect on Ni concentration or that Ni uptake by roots and/or transport to developing fruit was limiting. Plant nutritional status and fruit development stage influenced the coffee grain chemical composition. Furthermore, the variation in reducing sugars and starch content was more closely linked to the stage of fruit development than to N supply. A supposed relationship among the decreased of caffeine, starch, amino acids, and proteins with Ni content during green fruit development suggests a fundamental role for Ni in coffee fruit ripening. The interaction between N and Ni metabolism during fruit ripening might influence the chemical parameters involved in the coffee grain quality. This is the first report documenting changes in Ni concentrations of coffee fruit as a function of N fertilization rates and the development stage, but further research is needed to better understand the significance of N-Ni interaction in developing coffee fruit. 相似文献
70.
In order to establish critical potassium (K) concentration levels and K/calcium (Ca) plus magnesium (Mg) [K/Ca+Mg] ratios in potato petioles associated to maximum total tuber yields, an experiment was conducted under Brazilian conditions. Six K levels (0, 60, 120, 240, 480, and 960 kg K2O/ha as potassium sulphate) were applied in a randomized complete block design experiment with four replications. Baraka potato tubers were seeded, spaced 0.8 x 0.3 m, following the agronomic cultural practices recommended for the crop. After 48 days from plant emergence, plant tissue samples was collected from each plant, the youngest fully expanded leaves (YFEL) and the oldest but not senescent leaves (ONSL). Petioles from these leaves were analysed to their K, Ca, and Mg contents. At harvest, total, high grade, and weight tuber yields were increased to 733, 719, and 660 g/plant for the 353, 335, and 384 kg K2O/ha levels, respectively. These yields are double the Brazilian potato yield average. Petiole Ca and Mg concentrations were decreased by the K fertilizer treatments, whereas the opposite occurred with the K/Ca+Mg ratio. Potassium concentrations in the petioles from the YFEL and ONSL increased up to 10.44 and 7.13 g K/100 g petiole dry matter at the 672 and 654 kg K2O/ha levels, respectively. The K petiole gradient concentration was not affected by K fertilization. The K/Ca+Mg ratio for YFEL associated with the maximum total tuber yield was 7.24, while the K concentrations were 8.91 and 6.16 g K/100 g dry matter in petioles for the YFEL and ONSL, respectively. 相似文献