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排序方式: 共有7270条查询结果,搜索用时 15 毫秒
951.
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953.
Luara Isabela dos Santos Bruno Galvão-Filho Paula Cristina de Faria Caroline Junqueira Miriam Santos Dutra Santuza Maria Ribeiro Teixeira Maurício Martins Rodrigues Gerd Ritter Oliver Bannard Douglas Thomas Fearon Lis Ribeiro Antonelli Ricardo Tostes Gazzinelli 《Cancer immunology, immunotherapy : CII》2015,64(3):311-323
954.
In agricultural areas, Aspergillus
flavus, Aspergillus fumigatus and Aspergillus parasiticus are commonly identified in various feedstuffs and bioaerosols originated from feed handling. Some isolates belonging to these
fungal species could produce mycotoxins and constitute a risk factor for human and animal health. In this study, Fourier-transform
infrared spectroscopy was used for a rapid detection and characterization of 99 isolates collected from agricultural areas.
The results showed a first cluster corresponding to strains previously attributed to the A.
fumigatus group according to current taxonomic concepts, and a second cluster divided in 2 groups around reference strains of A.
flavus and A. parasiticus species. The toxigenic capacity of isolates was evaluated by high performance liquid chromatography coupled to mass spectrometry.
In the A. flavus group, only 6 strains of A. parasiticus and 4 strains of A. flavus were able to produce aflatoxins on culture media. FT-IR spectroscopy, respectively, allowed the differentiation of non-toxigenic
and toxigenic A. flavus and A. parasiticus isolates at 75 and 100%. Discrimination between toxigenic and non-toxigenic A. fumigatus was not possible because all of the isolates produced at least one mycotoxin. 相似文献
955.
956.
Sydney X. Lu Emma De Neef James D. Thomas Erich Sabio Benoit Rousseau Mathieu Gigoux David A. Knorr Benjamin Greenbaum Yuval Elhanati Simon J. Hogg Andrew Chow Arnab Ghosh Abigail Xie Dmitriy Zamarin Daniel Cui Caroline Erickson Michael Singer Hana Cho Robert K. Bradley 《Cell》2021,184(15):4032-4047.e31
957.
Hans Carl Hasselbalch Vibe Skov Thomas Stauffer Larsen Mads Thomassen Caroline Hasselbalch Riley Morten K. Jensen Ole Weis Bjerrum Torben A. Kruse 《PloS one》2014,9(1)
Identifying a distinct gene signature for myelofibrosis may yield novel information of the genes, which are responsible for progression of essential thrombocythemia and polycythemia vera towards myelofibrosis. We aimed at identifying a simple gene signature – composed of a few genes - which were selectively and highly deregulated in myelofibrosis patients. Gene expression microarray studies have been performed on whole blood from 69 patients with myeloproliferative neoplasms. Amongst the top-20 of the most upregulated genes in PMF compared to controls, we identified 5 genes (DEFA4, ELA2, OLFM4, CTSG, and AZU1), which were highly significantly deregulated in PMF only. None of these genes were significantly regulated in ET and PV patients. However, hierarchical cluster analysis showed that these genes were also highly expressed in a subset of patients with ET (n = 1) and PV (n = 4) transforming towards myelofibrosis and/or being featured by an aggressive phenotype. We have identified a simple 5-gene signature, which is uniquely and highly significantly deregulated in patients in transitional stages of ET and PV towards myelofibrosis and in patients with PMF only. Some of these genes are considered to be responsible for the derangement of bone marrow stroma in myelofibrosis. Accordingly, this gene-signature may reflect key processes in the pathogenesis and pathophysiology of myelofibrosis development. 相似文献
958.
CCR5 plays a critical and central role in HIV-1 infection and, to date, a number of genetic mutations and haplotypes within the gene have been found to positively or negatively influence an individual’s susceptibility and rate of disease progression. In this study, we have evaluated the influence of CCR5 haplotypes, HHA, HHC, HHD, and HHE, on CCR5 expression in healthy HIV-1 uninfected individuals from two populations, South African Africans (SAA, n?=?22) and South African Caucasians (SAC, n?=?31). CCR5 haplotypes were determined through sequencing and real time polymerase chain reaction. Flow cytometry was used to quantitate CCR5 surface expression, as both CCR5 density and percentage of CCR5-expressing cells, on B, T, natural killer (NK) cells and monocytes. SAA individuals positive for the HHA haplotype had significantly lower percentages of CCR5-expressing CD8+ T cells in comparison to individuals without HHA (P?=?0.001). HHC+ SAC individuals had significantly higher CCR5 molecules per cell (density) on NK (CD56+) and CD16+ CD56+ NK cell subsets (P?=?0.030 and P?=?0.024, respectively) compared to HHC? SAC individuals. Haplotypes HHD and HHE had no impact on CCR5 expression. Overall, our data highlight that the protective effect of the HHC haplotype in Caucasians might be explained by higher density of CCR5 expression on NK cells that is not evident in HHC+ SAA individuals. Findings raise the question as to the role of CCR5-expressing cells other than CD4+ T cells in protection from HIV-1 acquisition and disease progression. 相似文献
959.
Caroline Goode Jackson 《Journal of morphology》1981,167(1):65-90
Prenatal development of the eye in a microphthalmic hamster strain (“anophthalmic white”) is compared with established normal developmental periods. The mutant eye primordium is first distinguished at an average of ten gestational days (Period 6) by an incompletely invaginated optic cup, uniformly pseudostratified outer neuroepithelial layer and widely separated margins of the optic fissure. The outer layer of the mutant cup subsequently becomes abnormally thickened, especially posteriorly and midventrally, and, except in a few eyes with localized imperfect fusion, the optic fissure is unfused at twelve days (Period 9), by which time fusion is normally complete. At 13 to 15 days (Periods 10–11) the fissure is unfused or irregularly fused in regions of variable location and extent. The occurrence of fissure fusion with concomitant loss of continuity between inner and outer epithelial layers is generally restricted to expanded anterior regions in 14–16 day (Periods 11–12) eyes. The presence of presumptive neural retina in the outer layer of the cup characterizes the mutant eye; and to varying degrees, in day 13–16 eyes, the presumptive neural retina (1) provides persistent continuity between the two cup layers, (2) forms both fused and unfused margins of the optic fissure, and (3) extends into an outer position of the optic cup. As early as 13 days (Period 10), nerve fibers are present in the outer layer of the cup, and by the last prenatal and first postnatal days (Period 12), ectopic nerve fiber bundles are widely distributed. 相似文献
960.
Early Deficits in Glycolysis Are Specific to Striatal Neurons from a Rat Model of Huntington Disease
Caroline Gouarné Gwena?lle Tardif Jennifer Tracz Virginie Latyszenok Magali Michaud Laura Emily Clemens Libo Yu-Taeger Huu Phuc Nguyen Thierry Bordet Rebecca M. Pruss 《PloS one》2013,8(11)
In Huntington disease (HD), there is increasing evidence for a link between mutant huntingtin expression, mitochondrial dysfunction, energetic deficits and neurodegeneration but the precise nature, causes and order of these events remain to be determined. In this work, our objective was to evaluate mitochondrial respiratory function in intact, non-permeabilized, neurons derived from a transgenic rat model for HD compared to their wild type littermates by measuring oxygen consumption rates and extracellular acidification rates. Although HD striatal neurons had similar respiratory capacity as those from their wild-type littermates when they were incubated in rich medium containing a supra-physiological glucose concentration (25 mM), pyruvate and amino acids, respiratory defects emerged when cells were incubated in media containing only a physiological cerebral level of glucose (2.5 mM). According to the concept that glucose is not the sole substrate used by the brain for neuronal energy production, we provide evidence that primary neurons can use lactate as well as pyruvate to fuel the mitochondrial respiratory chain. In contrast to glucose, we found no major deficits in HD striatal neurons’ capacity to use pyruvate as a respiratory substrate compared to wild type littermates. Additionally, we used extracellular acidification rates to confirm a reduction in anaerobic glycolysis in the same cells. Interestingly, the metabolic disturbances observed in striatal neurons were not seen in primary cortical neurons, a brain region affected in later stages of HD. In conclusion, our results argue for a dysfunction in glycolysis, which might precede any defects in the respiratory chain itself, and these are early events in the onset of disease. 相似文献