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排序方式: 共有915条查询结果,搜索用时 15 毫秒
911.
Willian Rodrigues Macedo Ana Lourença Vaz do Nascimento Danúbia Aparecida Costa Nobre Jaqueline Dias Pereira Mirlem Gonçalves Rocha 《Acta Physiologiae Plantarum》2018,40(8):143
The auxin metabolism is practically elucidated, and the compounds that are part of the biosynthesis are well characterized, but the indole-3-ethanol or tryptophol, a molecule that has a regulatory position in the indole-3-acetic acid biosynthesis, still represents a gap in the understanding of this pathway. We examined the hypothesis that tryptophol present the function of plant growth regulation on soybean root development. We evaluated two doses of auxin and two doses of tryptophol (100 e 200 mg L??1), respectively, beside a control treatment (water), via leaf application, in soybean plants under V1–V2 phonological stages. After 18 days of application, the roots were collected for their volume and area measurement, thereafter small segments (0.5 cm of length), were collected at 1 cm below the root-collar, for anatomical analysis. We observed that the control showed greater area and root volume, but using 200 mg L??1 auxin and 100 mg L??1 tryptophol led to a radial increase of roots with significant increases in width radius vascular and cortical parenchyma. These results suggest that the application of both compounds had a potential of modify the vascular and ground tissues in soybean roots, which may be beneficial for the development of plants. 相似文献
912.
Mauricio Grecco Zaia Sandra Regina Pereira de Oliveira Cynthia Aparecida de Castro Edson Garcia Soares Ana Afonso Luis Gustavo S Monnazzi Oscar Peitl Filho Lúcia Helena Faccioli Fernanda de Freitas Anibal 《Memórias do Instituto Oswaldo Cruz》2015,110(6):726-731
The protective effect of infectious agents against allergic reactions has been
thoroughly investigated. Current studies have demonstrated the ability of some
helminths to modulate the immune response of infected hosts. The objective of the
present study was to investigate the relationship between Toxocara
canis infection and the development of an allergic response in mice
immunised with ovalbumin (OVA). We determined the total and differential blood and
bronchoalveolar lavage fluid cells using BALB/c mice as a model. To this end, the
levels of interleukin (IL)-4, IL-5 and IL-10 and anti-OVA-IgE were measured using an
ELISA. The inflammatory process in the lungs was observed using histology slides
stained with haematoxylin and eosin. The results showed an increase in the total
number of leukocytes and eosinophils in the blood of infected and immunised animals
at 18 days after infection. We observed a slight lymphocytic inflammatory infiltrate
in the portal space in all infected mice. Anti-OVA-IgE levels were detected in
smaller proportions in the plasma of immunised and infected mice compared with mice
that were only infected. Therefore, we concluded that T. canis
potentiates inflammation in the lungs in response to OVA, although anti-OVA-IgE
levels suggest a potential reduction of the inflammatory process through this
mechanism. 相似文献
913.
Characterization of serotypes and outer membrane protein profiles in enteroaggregative Escherichia coli strains. 总被引:2,自引:0,他引:2
Twenty-four Escherichia coli strains mainly isolated from children with diarrhea in São Paulo, and showing characteristics of enteroaggregative E. coli (EAEC), were characterized by serotyping and outer membrane protein (OMP) profiles. The relationship between these characteristics was evaluated, as well as the usefulness of OMP profiles in the clonal analysis of EAEC strains. All strains presented aggregative adherence to HeLa cells and were classified in two groups based on their interaction with the EAEC DNA probe. A diversity of serotypes and OMP profiles was observed in both groups studied. Although no significant correlation between serotypes and OMP profiles was observed, unique OMP profiles were identified in 80% of the probe-positive strains which were distributed in only 4 OMP profiles. This result may indicate the presence of a few clones in the probe-positive group. On the other hand, probe-negative strains seem to constitute a more diverse group. In general, the observed heterogeneity in serotypes and OMP profiles described in the present study suggest a great genetic diversity in EAEC isolates of either the same or different serotypes and in strains presenting the same EAEC markers identified in our community. 相似文献
914.
915.
Lucas Anjos Souza Sara Adrián López Andrade Sarah Caroline Ribeiro Souza Marlene Aparecida Schiavinato 《International journal of phytoremediation》2013,15(5):465-476
Soil contamination by heavy metals is a serious problem to humans due to its high level of toxicity. The heavy metal lead (Pb) is commonly used in industries and if the disposal of residues that contain this element is not done properly may result in tragic consequences to the organisms. In this experiment we assessed the potential of a forrage leguminous, Canavalia gladiata, to phytoremediate lead-contaminated soil under mycorrhizal influence. The experimental design was composed of 4 Pb doses (0, 250, 500, and 1000 mg kg?1 of soil) and the plants were inoculated or uninoculated with arbuscular mycorrhizal fungi (AMF). We observed that the nodulation was severely affected by the presence of Pb independently of the mycorrhizal status; most of the elements analyzed were affected independently of the mycorrhizal status with exception of P. The mycorrhizal colonization was able to restrict the entrance of Pb in plants under high concentrations of Pb but promoted it's accumulation in both organs under intermediate concentrations of this element. Besides the mycorrhization did not promote plant growth under Pb stress, the use of this plant may be considered to be used for phytostabilization purposes. 相似文献