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排序方式: 共有340条查询结果,搜索用时 15 毫秒
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Ellen Cristina Rivas Leonel Thalles Fernando Rocha Ruiz Carolina Marques Bedolo Silvana Gisele Pegorin Campos Sebastião Roberto Taboga 《Cell biology international》2021,45(11):2264-2274
The mammary gland (MG) and female prostate are plastic reproductive organs which are highly responsive to hormones. Thus, endocrine disruptors, such as bisphenol A (BPA) and exogenous estrogens, negatively affect glandular homeostasis. In addition to previously described alterations, changes in inflammatory markers expression also trigger the development of a microenvironment that contributes to tumor progression. The current work aimed to evaluate the inflammatory responses of the MG and prostate gland to BPA (50 µg/kg) and 17-β estradiol (35 µg/kg) exposure during the perinatal window of susceptibility. The results showed that at 6 months of age there was an increase in the number of phospho-STAT3 (P-STAT3) positive cells in the female prostate from animals perinatally exposed to 50 µg/kg BPA daily. In addition, the number of macrophages increased in these animals in comparison with nonexposed animals, as shown by the F4/80 marker. Despite an increase in the incidence of lobuloalveolar and intraductal hyperplasia, the MG did not show any difference in the expression of the four inflammatory markers evaluated: tumor necrosis factor-α, COX-2, P-STAT3, and F4/80. Analysis of both glands from the same animal led to the conclusion that exposure to endocrine disruptors during the perinatal window of susceptibility leads to different inflammatory responses in different reproductive organs. As the prostate is more susceptible to these inflammatory mechanisms, it is reasonable to affirm that possible neoplastic alterations in this organ are related to changes in the inflammatory pattern of the stroma, a characteristic that is not evident in the MG. 相似文献
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Oscar Fernandes Júnior Filipe Martins Santos Wesley Arruda Gimenes Nantes William Oliveira de Assis Gisele Braziliano de Andrade 《Studies on Neotropical Fauna and Environment》2020,55(2):149-154
ABSTRACT Azaras’s capuchin monkey (Sapajus cay) is a poorly studied species in ecological aspects. We investigated behavioral activities and diet of a group of S. cay in a remnant of the Brazilian Cerrado. We sought to identify the most frequent behavior that the group engaged in, as well as to verify possible differences in behavioral patterns and diet between adult males and females. From January to July 2012 we collected behavioral and foraging data for a group of 21 individuals using scan sampling. Behaviors and food items consumed were analyzed using percentages and two proportions Z-tests to assess differences between males and females. We obtained 878 scans in approximately 202 hours of sampling effort, resulting in 4,159 individual activity records of capuchin monkeys. The group allocated time to traveling (41.3%), resting (25.5%), feeding (14.3%), foraging (13.7%), and social activities (5.1%). Females spent more time foraging and feeding, while males spent more time resting. Fruits (61.4%), invertebrates (15.3%), and seeds (14.3%) were the most common food items consumed. We did not find differences in food consumption between sexes. Behavioral activities may be influenced by habitat quality of the studied area, opportunistic habits, and plasticity in the diet. 相似文献
325.
Gisele Ringeard 《Ocean Development & International Law》2013,44(2):121-136
Abstract It is traditional to consider that scientific research should be free. During the past, it has been affected by material and intellectual constraints; these constraints have evolved but exist still today. Because of the unity of the ocean, researchers, and especially oceanographers, claim a scientific immunity for their work. Because of the resources of the oceans, governments explicitly or implicitly consider freedom of scientific research as an application of the doctrine of economic liberalism, with its advantages and its disadvantages. Be that as it may, scientific research is absolutely necessary. To make compatible the demands of researchers and governments, freedom may become deontology. Researchers receive from authorities the largest rights of circulation applying to individuals, to materials, and to ideas. Researchers have, in counterpart, the duty to protect, to develop and to share the knowledge resulting from their work. 相似文献
326.
Monica Visnieski Alcantara Stenio Perdig?o Fragoso Gisele Fernanda Assine Picchi/ 《Memórias do Instituto Oswaldo Cruz》2014,109(4):511-513
Gene knockout is a widely used approach to evaluate loss-of-function phenotypes
and it can be facilitated by the incorporation of a DNA cassette having a
drug-selectable marker. Confirmation of the correct knockout cassette insertion
is an important step in gene removal validation and has generally been performed
by polymerase chain reaction (PCR) assays following a time-consuming DNA
extraction step. Here, we show a rapid procedure for the identification of
Trypanosoma cruzi transfectants by PCR directly from liquid
culture - without prior DNA extraction. This simple approach enabled us to
generate PCR amplifications from different cultures varying from
106-108 cells/mL. We also show that it is possible to
combine different primer pairs in a multiplex detection reaction and even to
achieve knockout confirmation with an extremely simple interpretation of a
real-time PCR result. Using the “culture PCR” approach, we show for the first
time that we can assess different DNA sequence combinations by PCR directly from
liquid culture, saving time in several tasks for T. cruzi
genotype interrogation. 相似文献
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Yugo Lima‐Melo Fabricio E. L. Carvalho Márcio O. Martins Gisele Passaia Rachel H. V. Sousa Milton C. Lima Neto Márcia Margis‐Pinheiro Joaquim A. G. Silveira 《植物学报(英文版)》2016,58(8):737-748
The physiological role of plant mitochondrial glutathione peroxidases is scarcely known. This study attempted to elucidate the role of a rice mitochondrial isoform(GPX1) in photosynthesis under normal growth and salinity conditions. GPX1 knockdown rice lines(GPX1s) were tested in absence and presence of 100 mM NaCl for 6 d.Growth reduction of GPX1 s line under non-stressful conditions, compared with non-transformed(NT) plants occurred in parallel to increased H_2O_2 and decreased GSH contents. These changes occurred concurrently with photosynthesis impairment, particularly in Calvin cycle's reactions, since photochemical efficiency did not change.Thus, GPX1 silencing and downstream molecular/metabolic changes modulated photosynthesis differentially. In contrast, salinity induced reduction in both phases of photosynthesis, which were more impaired in silenced plants.These changes were associated with root morphology alterations but not shoot growth. Both studied lines displayed increased GPX activity but H_2O_2 content did not change in response to salinity. Transformed plants exhibited lower photorespiration, water use efficiency and root growth, indicating that GPX1 could be important to salt tolerance. Growth reduction of GPX1 s line might be related to photosynthesis impairment, which in turn could have involved a cross talk mechanism between mitochondria and chloroplast originated from redox changes due to GPX1 deficiency. 相似文献
330.
F.X. Coudé G. Grimber Ph. Parvy P. Kamoun 《Biochemical and biophysical research communications》1981,102(3):1016-1020
A sensitive assay for the determination of N-Acetylglutamate synthetase activity in human liver has been developed. The activity was markedly stimulated by L-Arginine and inhibited by its product N-Acetylglutamate. Apparent kinetic properties were similar to those of the rat liver enzyme. This work provides the first evidence for the presence of N-Acetylglutamate synthetase activity in human. 相似文献