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991.
Environmental and spatial processes influencing phytoplankton biomass along a reservoirs‐river‐floodplain lakes gradient: A metacommunity approach
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Jascieli Carla Bortolini Alfonso Pineda Luzia Cleide Rodrigues Susicley Jati Luiz Felipe Machado Velho 《Freshwater Biology》2017,62(10):1756-1767
992.
Flávia Rosa Santoro Gilney Charll Santos Washington Soares Ferreira Júnior Leonardo da Silva Chaves Thiago Antonio Sousa Araújo Andre Luiz Borba Nascimento André Sobral Josivan Soares Silva Juliana Loureiro Almeida Campos Ulysses Paulino Albuquerque 《Evolutionary biology》2017,44(2):216-226
The malaria hypothesis, which addresses a strong selective pressure on human genes resulting from a chain of processes that originated with the practice of agriculture, is an example of an evolutionary consequence of niche construction. This scenario has led us to formulate the following questions: Are the genetic adaptations of populations with a history of contact with malaria reflected in the local medical systems? Likewise, could environmental changes (deforestation) and the incidence of malaria result in an adaptive response in these local health care systems? We collected secondary data for the entire African continent from different databases and secondary sources and measured the response of health care systems as the variation in the richness of antimalarial medicinal plants. Our results did not indicate a cause-and-effect relationship between the tested variables and the medical systems, but a subsequent analysis of variance showed an increase in the mean of medicinal plants in regions with a higher incidence of malaria prior to disease control measures. We suggest that this response had a greater impact on local medical knowledge than other variables, such as genetic frequency and deforestation. 相似文献
993.
994.
Detection of Toxoplasma gondii antibodies in captive non‐human primates in the Amazon region,Brazil
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995.
Sérgio Monteiro de Almeida 《Mycopathologia》2017,182(3-4):393-396
The immune reconstitution inflammatory syndrome (IRIS) is a deregulated inflammatory response to invading microorganisms. It is manifested when there is an abrupt change in host immunity from an anti-inflammatory and immunosuppressive state to a pro-inflammatory state as a result of rapid depletion or removal of factors that promote immune suppression or inhibition of inflammation. The aim of this paper is to discuss and re-interpret the possibility of association of paracoccidioidomycosis (PCM) with IRIS in the central nervous system (CNS) in a case from Brazil published by Silva-Vergara ML. et al. (Mycopathologia 177:137–141, 6). An AIDS patient who was not receiving medical care developed pulmonary PCM successfully treated with itraconazole. The patient developed central nervous system PCM (NPCM) after starting the ARV therapy with recovery of immunity and control of HIV viral load, although it was not interpreted as IRIS by the authors, it fulfills the criteria for CNS IRIS. This could be the first case of NPCM associated with IRIS described. Although not frequent, IRIS must be considered in PCM patients and HIV, from endemic areas or patients that traveled to endemic areas, receiving ARV treatment and with worsening symptoms. 相似文献
996.
Astride S. M. Djabou Luiz J. C. B. Carvalho Qing X. Li Nicolas Niemenak Songbi Chen 《Acta Physiologiae Plantarum》2017,39(4):91
Postharvest physiological deterioration (PPD) of cassava (Manihot esculenta) storage roots is a complex physiological and biochemical process which involve many regulatory networks linked with specific proteins modulation and signaling transduction pathways. However, it is poorly understood regarding biological regulation, and the interactions among protein groups and signals to determine PPD syndrome in cassava storage roots. This review sheds some light on the possible molecular mechanisms involved in reactive oxygen species (ROS), calcium signaling transduction, and programmed cell death (PCD) in cassava PPD syndrome. A model for predicting crosstalk among calcium signaling, ROS and PCD is suggested to fine-tune PPD syndrome. This would clues to cassava molecular breeding to alleviate the PPD effects on the shelf-life. 相似文献
997.
Fábio Henrique Krenchinski Leandro Paiola Albrecht Alfredo Junior Paiola Albrecht Victor José Salomão Cesco Danilo Morilha Rodrigues Roberto Luis Portz Luiz Henrique Saes Zobiole 《Acta Physiologiae Plantarum》2017,39(2):63
The planting of RR2 Intacta soybeans by farmers has been expanding strongly. However, some visual injuries have been noted after glyphosate application. The aim of this study was to evaluate the influence of glyphosate application on chlorophyll, photosynthesis and water use of four Intacta RR2 soybean cultivars. The experiment was conducted in a greenhouse, in a randomized block design with a 3 × 4 factorial scheme, consisting of three glyphosate rates and four soybean cultivars. The glyphosate formula used was isopropylamine salt + potassium salt. The parameters analyzed were phytotoxicity at 7, 14, 21 and 28 days after application, and total chlorophyll index at 0, 3, 7, 14, 21, 28, 35, 42 and 49 days after application. Furthermore, 40 days after application, the net CO2 assimilation rate (A), transpiration rate (E), stomatal conductance (G), and internal CO2 concentration (Ci) were evaluated as well. The water-use efficiency (WUE) and carboxylation efficiency were calculated. The data were submitted to analysis of variance and compared by the Tukey’s test (p ≤ 0.05), followed by regression analysis. The phytotoxicity influence could be seen until 21 days after application, in which Monsoy 6210 IPRO cultivar was the most injured. The increasing doses promoted a reduction of the chlorophyll level up to 35 days after application in Monsoy 6410 IPRO. The cultivars tested here showed similar chlorophyll index values. On the 3rd, 7th and 14th DAA (Fig. 5a–c), there was a significant linear decline in the chlorophyll index with rising glyphosate dose for all four cultivars. The chlorophyll index cultivars were not influenced by the doses on the 42nd and 49th DAA. There was no difference in water use and carboxylation efficiency. The parameters A, E and A/Ci showed a positive correlation as the doses increased, while Ci declined, in both cultivars. The application of glyphosate on these soybean cultivars causes different injuries according to the sensitivity. In general, RR2 soybeans have the ability to recover from visual intoxication injuries and reestablish the normal chlorophyll production and photosynthetic parameters after glyphosate application. 相似文献
998.
Vinícius Coelho Kuster Silvana Aparecida Barbosa de Castro Fernando Henrique Aguiar Vale 《Acta Physiologiae Plantarum》2017,39(4):103
Plasticity in plants could be changed due to abiotic factors, tending to increase fitness across environments. In the Neotropical savannah, a strong water deficit during the dry season is one of the main factors limiting the plasticity in physiological responses of plants. The present study aims to assess the plasticity in physiological responses and vegetative phenology of three plant species of the Neotropical savannah (Cerrado in Brazil) during the dry and the rainy seasons. The three species, Byrsonima verbascifolia, Roupala montana, and Solanum lycocarpum, occur in Serra do Cipó in the state of Minas Gerais, Brazil. The development and vegetative phenology of individuals of these three species were evaluated over the course of 1 year. In February 2012 (rainy season) and August 2012 (dry season), stomatal conductance (g s), water potential (Ψ), photosynthetic quantum yield, and concentration of leaf photosynthetic pigments were measured. The relative distance among the physiological parameters of all individuals within each season was measured using the relative distance plasticity index. B. verbascifolia has pronounced senescence in July and lost leaves completely by the early September, while R. montana and S. lycocarpum have green leaves throughout the year. The three studied species had greater control of stomatal opening during the dry season. S. lycocarpum and R. montana had negative water potential values in the dry season and in the middle of the day in both seasons. In the dry season, the three species exhibited a decrease in F v/F m, with values between 0.7 and 0.75. The relative distance plasticity index varied from 0 to 1. R. montana demonstrated the greatest plasticity and S. lycocarpum had lower plasticity. Then, a seasonal effect on physiological response was observed in all three model-species, with lower values for leaf water potential and stomatal conductance, and increased photoinhibition, in the dry season. Ecophysiological traits, such as stomatal conductance and leaf water potential, exhibited the greatest plasticity. In addition, there was a seasonal effect on the plasticity in physiological responses of the three plants species of the Neotropical savannah. The results are contradicting the idea that water restriction in the dry season would reduce the plasticity in most species of the Neotropical savannah. 相似文献
999.
Eugênia Barbosa Varella Costa Pedro Henrique de Faria Peres Francisco Grotta-Neto Alexandre Vogliotti Ubiratan Piovezan 《Studies on Neotropical Fauna and Environment》2017,52(1):37-42
Morphometric feces data are used to identify ungulates, but their effectiveness is questioned by numerous authors. Herein, we evaluated the efficiency of this tool in discriminating scat samples from Neotropical deer with sympatric distributions. We performed discriminant analysis of previously identified scat samples (n = 204). The accuracy of discriminant analysis (56–92%) was lower than the confidence limit established in this study in all sympatric combinations expected in these biomes. These results demonstrate serious limitations regarding the use of scat morphometry for species identification of Neotropical deer and reinforce the need to use non-invasive genetic techniques. 相似文献
1000.