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排序方式: 共有3201条查询结果,搜索用时 350 毫秒
31.
Ulrika Evermann Christian Gaser Bianca Besteher Kerstin Langbein Igor Nenadi 《Schizophrenia bulletin》2020,46(6):1524
BackgroundPsychotic-like experiences (PLE) are present in nonclinical populations, yet their association with brain structural variation, especially markers of early neurodevelopment, is poorly understood. We tested the hypothesis that cortical surface gyrification, a putative marker of early brain development, is associated with PLE in healthy subjects. MethodsWe analyzed gyrification from 3 Tesla MRI scans (using CAT12 software) and PLE (positive, negative, and depressive symptom dimensions derived from the Community Assessment of Psychic Experiences, CAPE) in 103 healthy participants (49 females, mean age 29.13 ± 9.37 years). A subsample of 63 individuals completed tasks from the Wechsler Adult Intelligence Scale and Controlled Oral Word Association Test. Estimated IQ and a composite neuropsychological score were used to explore mediation pathways via cognition. ResultsPositive PLE distress was negatively associated with gyrification of the left precuneus. PLE depression dimension showed a negative association with gyrification in the right supramarginal and temporal region. There was no significant mediating effect of cognition on these associations. ConclusionOur results support a neurobiological psychosis spectrum, for the first time linking an early developmental imaging marker (rather than volume) to dimensional subclinical psychotic symptoms. While schizophrenia risk, neurodevelopment, and cognitive function might share genetic risk factors, additional mediation analyses did not confirm a mediating effect of cognition on the gyrification-psychopathology correlation. 相似文献
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Combining different assays and chemical analysis to characterize the genotoxicity of waters impacted by textile discharges
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Francine I. Vacchi Josiane A. S. Vendemiatti Vanessa Brosselin Bianca Ferreira da Silva Maria Valnice B. Zanoni Michel DeMeo Sylvie Bony Alain Devaux Gisela A. Umbuzeiro 《Environmental and molecular mutagenesis》2016,57(7):559-571
Waters receiving textile discharges can exhibit genotoxic and mutagenic activity, which has been related to the presence of dyes and aromatic amines as synthesis precursors or byproducts. The aim of this study was to identify dyes and aromatic amines in water samples impacted by textile discharges, and to evaluate the genotoxic responses of these samples using the Salmonella/microsome assay in strains TA98 and YG1041, and the Fpg‐modified comet assay in the RTL‐W1 fish cell line. The genotoxicity of river samples downstream of the discharge was greater than the upstream samples in both of the Ames tests. The Fpg‐modified comet assay detected similar levels of DNA damage in the upstream and downstream samples. Mutagenicity was not detected with TA98, except for the Quilombo River samples, but when YG1041 was used as the tester strain mutagenicity was detected for all sites with a very different profile in upstream sites relative to the other sites. The mutagenic response strongly indicated that aromatic amines or dyes were contributing to the mutagenic activity downstream. The impact of textile discharges was also confirmed by chemical analysis, because the highest concentrations of azo dyes and aromatic amines were detected in the river downstream. This study shows the value of combining assays measuring complementary endpoints to better characterize the mutagenicity of environmental samples, with the advantage that this approach provides an indication of what classes of compounds are responsible for the effect. Environ. Mol. Mutagen. 57:559–571, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
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Bianca Siegel John P. Bent Samuel Weinstein 《International journal of pediatric otorhinolaryngology》2014
A case of distal tracheal rupture is described, literature review reveals two previously reported cases of neonatal distal tracheal rupture, as well as 14 cases of anterior subglottic rupture. All patients had shoulder dystocia, and 59% had associated brachial plexus injury. Delayed diagnosis (>3 days) was common in the distal tracheal group (66%), compared to 0% in the anterior subglottic group. The 2 distal tracheal rupture patients were initially managed conservatively, but ultimately required open repair. Distal tracheal rupture is exceedingly rare and more difficult to diagnose and manage than the more common anterior subglottic rupture. 相似文献
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Evandro Luís Niero Bianca Rocha-Sales Camila Lauand Beatriz Araujo Cortez Marcelo Medina de Souza Paula Rezende-Teixeira Marcel Shiniti Urabayashi Adam Arai Martens Jorge Henrique Neves Gláucia Maria Machado-Santelli 《Journal of experimental & clinical cancer research : CR》2014,33(1):37
Some cancers like melanoma and pancreatic and ovarian cancers, for example, commonly display resistance to chemotherapy, and this is the major obstacle to a better prognosis of patients. Frequently, literature presents studies in monolayer cell cultures, 3D cell cultures or in vivo studies, but rarely the same work compares results of drug resistance in different models. Several of these works are presented in this review and show that usually cells in 3D culture are more resistant to drugs than monolayer cultured cells due to different mechanisms. Searching for new strategies to sensitize different tumors to chemotherapy, many methods have been studied to understand the mechanisms whereby cancer cells acquire drug resistance. These methods have been strongly advanced along the years and therapies using different drugs have been increasingly proposed to induce cell death in resistant cells of different cancers. Recently, cancer stem cells (CSCs) have been extensively studied because they would be the only cells capable of sustaining tumorigenesis. It is believed that the resistance of CSCs to currently used chemotherapeutics is a major contributing factor in cancer recurrence and later metastasis development. This review aims to appraise the experimental progress in the study of acquired drug resistance of cancer cells in different models as well as to understand the role of CSCs as the major contributing factor in cancer recurrence and metastasis development, describing how CSCs can be identified and isolated. 相似文献
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