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81.
Anton Débora Bublitz Guzman Frank Lino Vetö Nicole Moreira Krause Felipe Augusto Kulcheski Franceli Rodrigues Coelho Ana Paula Durand Duarte Guilherme Leitão Margis Rogério Dillenburg Lúcia Rebello Turchetto-Zolet Andreia Carina 《Molecular biology reports》2020,47(2):1033-1043
Molecular Biology Reports - Eugenia uniflora is an Atlantic Forest native species, occurring in contrasting edaphoclimatic environments. The identification of genes involved in response to abiotic... 相似文献
82.
Jason Yang Raphael Guzman James Richards S. Nandi 《In vitro cellular & developmental biology. Plant》1980,16(6):502-506
Summary Mammary tumor epithelial cells from BALB/cfC3H mice were dispersely embedded inside the collagen gels in Ham's F-12 medium
containing horse serum. A sustained cell growth leading to a 5- to 10-fold increase in cell number over initial level was
observed in less than 2 weeks. The extent of this growth was found to be dependent on serum concentration. However, addition
of various protein and steroid hormones, both singly and in combination, to low-serum-containing medium failed to achieve
a comparable level of growth to that promoted by higher serum concentration. Mammary tumor cells can now be consistently propagated
in primary culture.
This investigation was supported by Grants CA05388 and CA09041 awarded by the National Cancer Institute, Department of Health,
Education and Welfare, and by cancer research funds of the University of California. 相似文献
83.
Binocular rivalry--the alternations in perception that occur when different images are presented to the two eyes--has been the subject of intensive investigation for more than 160 years. The psychophysical properties of binocular rivalry have been well described, but newer imaging and electrophysiological techniques have not resolved the issue of where in the brain rivalry occurs. The most recent evidence supports a view of rivalry as a series of processes, each of which is implemented by neural mechanisms at different levels of the visual hierarchy. Although unanswered questions remain, this view of rivalry might allow us to resolve some of the controversies and apparent contradictions that have emerged from its study. 相似文献
84.
Waterbird response indicates floodplain wetland restoration 总被引:1,自引:0,他引:1
Heath M. Hagy Christopher S. Hine Michelle M. Horath Aaron P. Yetter Randolph V. Smith Joshua D. Stafford 《Hydrobiologia》2017,798(1):119-126
Filamentous cyanobacteria disturb food collection in Daphnia by mechanical interference with the filtering apparatus by the long trichomes. The intensity of this interference depends on the water temperature and the Daphnia body size. However, Daphnia are capable of breaking down the filaments, therefore improving the palatability of the cyanobacteria. The main objective of this study was to test whether the shortening of cyanobacterial filaments and the ensuing clearance rate of Daphnia would increase at higher temperatures to a greater degree in small-bodied Daphnia species than in large-bodied one. Laboratory feeding experiments were conducted in order to measure variation in the length of Cylindrospermopsis raciborskii trichomes and to calculate clearance rate. The filament length and the cyanobacteria clearance rate by Daphnia were calculated following their exposure to grazing by large-bodied D. pulicaria and small-bodied D. longispina in 20, 24, and 28°C. Rising temperature did not affect the intensity of breakage of C. raciborskii trichomes by D. pulicaria and caused decrease in clearance rate of this species, whereas for D. longispina, the temperature increase enhanced both filament breakage and clearance rate. We suggest that these temperature-related changes may affect relative competitive performance of Daphnia species in the presence of cyanobacteria. 相似文献
85.
Bloomfield Laura S. P. Tracey Christopher Mbabazi Edith Schultz Rhiannon L. Henderson Rebecca Bardosh Kevin Randolph Shannon Paige Sarah 《EcoHealth》2022,19(2):299-314
EcoHealth - The majority of emerging and re-emerging infectious diseases in people are zoonotic. Despite substantial research in communities adjacent to protected areas with high levels of... 相似文献
86.
Krohmer RW Martinez D Mason RT 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2004,139(1):55-64
The renal sexual segment (RSS) of immature Northern and Diamondback Water Snakes and Red-Sided Garter Snakes exhibited varying responses to testosterone or 17beta-estradiol. In both male and female water snakes, kidney mass was not a reliable indicator of hormone treatment, whereas tubule diameter, epithelial height and number of sexual granules responded to hormone treatment. In male water snakes, either hormone initiated granule development by day 16; by day 23, only testosterone increased granule density. Female water snakes receiving either hormone exhibited a small number of granules by day 16; by day 23, granules increased only in Diamondback Water Snakes receiving testosterone. Hormones did not initiate RSS hypertrophy in female Red-Sided Garter Snakes. Tubule diameter and epithelial height of testosterone-treated males exhibited significant hypertrophy, while 17beta-estradiol initiated significant increases in tubule diameter. Garter snakes initiated sexual granule development in response to hormone treatment with males exhibiting a greater response than females and testosterone stimulating a greater response than 17beta-estradiol. Sex steroids appear to mimic sexual maturity in immature snakes initiating RSS development. Whereas the RSS of adult males respond to testosterone, our data suggest specific changes in the RSS of females during maturation effectively negates the effect of 17beta-estradiol evident in immature female RSS. 相似文献
87.
The chemokine receptor CXCR3, which was shown to take part in many inflammatory processes, is considered as a Th1 specific marker. Here, we show in a mouse model that CXCR3 expressing CD4(+) cells preferentially migrate to the peritoneal cavity under steady-state conditions. The peritoneal cavity milieu leads to an up-regulated expression of CXCR3. However, blocking of known ligands of this chemokine receptor did not alter the preferential migration. The peritoneal cavity environment also results in an increased percentage of memory cells producing cytokines. Up-regulation of IFNγ production occurs mostly in CXCR3(+) cells considered as Th1, whereas the up-regulation of IL-4 affects mostly in CXCR3(-) cells which are considered as Th2. We conclude that the peritoneal cavity does not change the Th-lineage of the cells, but that domination of this anatomic niche by Th1 cells rather results from preferential migration to this compartment. 相似文献
88.
The Horizontal Gene Transfer DataBase (HGT-DB) is a genomic database that includes statistical parameters such as G+C content, codon and amino-acid usage, as well as information about which genes deviate in these parameters for prokaryotic complete genomes. Under the hypothesis that genes from distantly related species have different nucleotide compositions, these deviated genes may have been acquired by horizontal gene transfer. The current version of the database contains 88 bacterial and archaeal complete genomes, including multiple chromosomes and strains. For each genome, the database provides statistical parameters for all the genes, as well as averages and standard deviations of G+C content, codon usage, relative synonymous codon usage and amino-acid content. It also provides information about correspondence analyses of the codon usage, plus lists of extraneous group of genes in terms of G+C content and lists of putatively acquired genes. With this information, researchers can explore the G+C content and codon usage of a gene when they find incongruities in sequence-based phylogenetic trees. A search engine that allows searches for gene names or keywords for a specific organism is also available. HGT-DB is freely accessible at http://www.fut.es/~debb/HGT. 相似文献
89.
Sandra B. Barker Randolph T. Barker Nancy L. McCain Christine M. Schubert 《Anthrozo?s》2017,30(4):595-606
Using data from a previously published study on effects of a canine-assisted activity (CAA) on college student stress the week before final examinations, we examined whether participation in this activity had effects on perceptions of 1) family supports (i.e., emotional distance to family members and pets) and 2) current stressors. A total of 74 students completed the Family Life Space Diagram (FLSD), which uses an individual's structured drawings of distances between symbols of self and living entities, organizations, and stressors to reflect “emotional distances.” Participants were randomly assigned to order of CAA or FLSD, which was the intervention study control condition. Groups completed the FLSD after participating in CAA (Group A, n = 34) or prior to CAA (Group B, n = 40). Participants were primarily white (56.8%) females (75.7%) with a mean age of 19.38 years (SD = 1.75). Significant differences with large effect sizes were found for both groups in distances between 1) self-closest and self-average family member (Group A: t = 7.02, df = 33, p < 0.001, d = 1.205; Group B: t = 6.25, df = 39, p < 0.001, d = 0.987) and 2) self-closest personal stressor (t = 2.93, df = 18, p = 0.009, d = 1.311) and self-average personal stressor (t = 2.54, df = 18. p = 0.020, d = 1.138). In both cases, Group A (FLSD following CAA) placed personal stressors in closer proximity to self. Although CAA did not affect students’ current perceptions of family and pet relationships, the intervention may have increased their abilities to cope with personal stressors. Modified stress theory supports the proposition that positive emotions associated with CAA engage positive coping strategies, resulting in more positive perceptions of stressors. 相似文献
90.
Carl Bannerman Natalie Guzman Rachit Kumar Chelsea Nnebe Jordan Setayesh Amitej Venapally Jonathan H. Sussman 《Molecular biology of the cell》2020,31(24):2640
The importance of diversity is self-evident in medicine and medical research. Not only does diversity result in more impactful scientific work, but diverse teams of researchers and clinicians are necessary to address health disparities and improve the health of underserved communities. MD/PhD programs serve an important role in training physician-scientists, so it is critical to ensure that MD/PhD students represent diverse backgrounds and experiences. Groups who are underrepresented in medicine and the biomedical sciences include individuals from certain racial and ethnic backgrounds, individuals with disabilities, individuals from disadvantaged backgrounds, and women. However, underrepresented students are routinely discouraged from applying to MD/PhD programs due to a range of factors. These factors include the significant cost of applying, which can be prohibitive for many students, the paucity of diverse mentors who share common experiences, as well as applicants’ perceptions that there is inadequate support and inclusion from within MD/PhD programs. By providing advice to students who are underrepresented in medicine and describing steps programs can take to recruit and support minority applicants, we hope to encourage more students to consider the MD/PhD career path that will yield a more productive and equitable scientific and medical community. 相似文献