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991.
Classification and surgical correction of gynecomastia 总被引:17,自引:0,他引:17
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J. P. R. Martins E. R. Santos L. C. A. Rodrigues A. B. P. L. Gontijo A. R. Falqueto 《Biologia Plantarum》2018,62(4):793-800
Cytokinins (CKs) are often used during the in vitro cultivation of plant species. However, it is not clear how CKs, such as 6-benzylaminopurine (BAP), affect photosystem PS) II functionality and leaf anatomy over a long period of in vitro plant propagation. The aim of this study was to analyze the residual effects of BAP on the photosynthetic performance and leaf anatomy of Aechmea blanchetiana after 120 d without exposure to CKs. Aechmea blanchetiana plants previously grown in vitro were transferred to Murashige and Skoog (MS) culture media containing 0, 5, 10, 15, or 20 μM BAP. After 60 d on the MS medium with BAP, explants were subcultivated twice on the MS medium without growth regulators, first in a stationary liquid medium for 60 d and then in a solidified medium with 6 g dm-3 agar for 60 d. Leaf anatomy, pigment content, and chlorophyll a fluorescence were assessed for plants from each treatment after 120 d on the CK-free medium. Stomatal density presented a negative linear correlation with BAP concentration. Pigment content decreased in plants subjected to previous BAP exposure. An increase in absorbed energy flux per reaction center (ABS/RC) and a sharp decrease in energy transport flux (ETo/RC) followed by an increase in energy dissipation flux (DIo/RC) also occurred. Furthermore, maximum quantum yield (FV/FM) decreased as a function of BAP concentration. Thus, the use of BAP during in vitro propagation of A. blanchetiana induced long-term physiological defects. 相似文献
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Lúcio M. Barbosa Bruna C. Barros Moreno de Souza Rodrigues Luciano K. Silva Mitermayer G. Reis Ronald E. Blanton 《International journal for parasitology》2018,48(14):1149-1154
Eradication or local extinction of the human parasite Schistosoma mansoni is a goal for many control programs. Population genetic analyses are helping to evaluate and guide these efforts, yet what to sample, how to sample and how densely to sample is not well established. We determined the S. mansoni allele frequency profile of nearly all infected inhabitants in two small Brazilian communities and created sub-samples representing 5–50% of all detected human infections (infrapopulations). Samples were selected at random with replacement, and each size class was replicated 100 times. Mean pairwise differentiation for all infrapopulations (Di) and the variance effective population size (Ne) were calculated for each sample. Prior to community-wide treatment, the true mean Di was moderate (0.095–0.123) and Ne large (>30,000). Most samples of <50% of those infected produced estimates outside of 5% of the true value. For estimates within 10%, sample sizes of >15% of all infrapopulations were required. At the 3?year follow-up after treatment, the Di increased and Ne was reduced by >15 fold. At this time sampling of >30–45% was needed to achieve the same accuracy. Following a second treatment and 4?years from baseline, the Di further increased and Ne decreased with little change in the sampling effort required. Extensive sampling is required for accurate estimates of these important population parameters. Characteristics such as population census size, infection prevalence, the community’s treatment history and the degree of infrapopulation differentiation should be taken into account. The intensity of infection was weakly correlated with the ability of a single infrapopulation to represent the component population (Dic), indicating a tendency toward random acquisition of parasite genotypes. This also suggests that targeted sampling from those most heavily infected will better represent the genetic diversity of the whole community than a random sample of infrapopulations. 相似文献
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Vitamin C modulates glutamate transport and NMDA receptor function in the retina 总被引:1,自引:0,他引:1 下载免费PDF全文
Ivan Domith Renato Socodato Camila C. Portugal Andressa F. Munis Aline T. Duarte‐Silva Roberto Paes‐de‐Carvalho 《Journal of neurochemistry》2018,144(4):408-420
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Invasive Ruffe (Gymnocephalus cernua) has caused substantial ecological damage in North America, parts of Western Europe, Scandinavian countries, and the United Kingdom. The objectives of this review are to define Ruffe’s native and non-native range, examine life history requirements, explore the life cycle, and differentiate between life stages. We compare data from its native and non-native ranges to determine if there are any differences in habitat, size, age, genotype, or seasonal migration. Literature from both the native and non-native ranges of Ruffe, with some rare, translated literature, is used. In each life stage, Ruffe exhibit plasticity with regard to chemical, physical, biological, and habitat requirements. Adult Ruffe has characteristics that allow them to adapt to a range of environments, including rapid maturation, relatively long life and large size (allowing them to reproduce many times in large batches), batch spawning, genotype and phenotype (having plasticity in their genetic expression), tolerance to a wide range of water quality, broad diet, and multiple dispersal periods. There is, however, variability among these characteristics between the native, non-native North American, and European non-native populations, which presents a challenge to managing populations based on life history characteristics. Monitoring and preventative strategies are important because, based on Ruffe’s variable life history strategies and its recent range expansion, all of the Laurentian Great Lakes and many other water bodies in the UK, Europe, and Norway are vulnerable to Ruffe establishment. 相似文献
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Fábia Guimarães-Dias Anna C. Neves-Borges Alessandra J. Conforte Leonardo Giovanella-Kampmann André V. J. Ferreira Regina M. S. Amorim Magda A. Benevent Maria Eugênia Lisei de Sá Rosilene O. Mesquita Fabiana A. Rodrigues Alexandre L. Nepomuceno Eduardo Romano Marcelo E. Loureiro Maria Fátima Grossi-de-Sá Márcio Alves-Ferreira 《Plant Molecular Biology Reporter》2016,34(6):1167-1180