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排序方式: 共有1377条查询结果,搜索用时 109 毫秒
31.
Angela M. C. Rose Esther Kissling Alin Gherasim Itziar Casado Antonino Bella Odile Launay Mihaela Lazr Sierk Marbus Monika Kuliese Ritva Syrjnen Ausenda Machado Sanja Kure
i Filipovi Amparo Larrauri Jesús Castilla Valeria Alfonsi Florence Galtier Alina Ivanciuc Adam Meijer Aukse Mickiene Niina Ikonen Vernica Gmez Zvjezdana Lovri Makari Alain Moren Marta Valenciano 《Influenza and other respiratory viruses》2020,14(3):302-310
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Paula Ecaterina Florian Madalina Icriverzi Claudia Mihaela Ninciuleanu Elvira Alexandrescu Bogdan Trica Silviu Preda Raluca Ianchis Anca Roseanu 《Materials》2020,13(23)
Salecan is a microbial polysaccharide suitable to obtain hydrogel for biomedical applications due to the excellent hydrophilicity and biocompatibility properties. In this work, Salecan of different concentrations was introduced into polymethacrylic acid (PMAA) in the presence of clay to form novel semi synthetic hydrogel nanocomposites systems and loaded afterwards with doxorubicin (DOX). The physical–chemical characteristics of the nanocomposites systems and their effect on the viability, and morphology of MDBK (Madin–Darby bovine kidney), HT-29 human colorectal adenocarcinoma and Colo 205 human colon adenocarcinoma cell lines were investigated. DOX release from the nanocomposite systems, cell up-take and subsequent effect on cell proliferation was also analyzed. It was found that Salecan concentration determined the swelling behavior, structural parameters and morphological features of the nanocomposite systems. The hydrogen bonds strongly influenced the formation of PMAA–Salecan–clay systems, each component bringing its own contribution, thus demonstrating the achievement of an advanced crosslinked network and a more compacted hydrogel nanocomposite morphology. All the synthesized nanocomposites had negligible toxicity to normal MDBK cells and chemoresistent HT-29 cell line, whereas in the case of Colo 205 cells a decrease by 40% of the cell viability was obtained for the sample containing the highest amount of Salecan. This effect was correlated with the lowest pore size distribution leading to highest available specific surface area and entrapped amount of DOX which was further released from the nanocomposite sample. Corroborating all the data it can be suggested that the synthesized nanocomposites with Salecan and clay could be good candidates as vehicles for chemotherapeutic agents. 相似文献
33.
Selfish supernumerary chromosome reveals its origin as a mosaic of host genome and organellar sequences 总被引:1,自引:0,他引:1
MM Martis S Klemme AM Banaei-Moghaddam FR Blattner J Macas T Schmutzer U Scholz H Gundlach T Wicker H Simková P Novák P Neumann M Kubaláková E Bauer G Haseneyer J Fuchs J Dolezel N Stein KF Mayer A Houben 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(33):13343-13346
Supernumerary B chromosomes are optional additions to the basic set of A chromosomes, and occur in all eukaryotic groups. They differ from the basic complement in morphology, pairing behavior, and inheritance and are not required for normal growth and development. The current view is that B chromosomes are parasitic elements comparable to selfish DNA, like transposons. In contrast to transposons, they are autonomously inherited independent of the host genome and have their own mechanisms of mitotic or meiotic drive. Although B chromosomes were first described a century ago, little is known about their origin and molecular makeup. The widely accepted view is that they are derived from fragments of A chromosomes and/or generated in response to interspecific hybridization. Through next-generation sequencing of sorted A and B chromosomes, we show that B chromosomes of rye are rich in gene-derived sequences, allowing us to trace their origin to fragments of A chromosomes, with the largest parts corresponding to rye chromosomes 3R and 7R. Compared with A chromosomes, B chromosomes were also found to accumulate large amounts of specific repeats and insertions of organellar DNA. The origin of rye B chromosomes occurred an estimated ~1.1-1.3 Mya, overlapping in time with the onset of the genus Secale (1.7 Mya). We propose a comprehensive model of B chromosome evolution, including its origin by recombination of several A chromosomes followed by capturing of additional A-derived and organellar sequences and amplification of B-specific repeats. 相似文献
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Porta F Radunovic G Vlad V Micu MC Nestorova R Petranova T Iagnocco A 《Rheumatology (Oxford, England)》2012,51(6):976-982
The use of Doppler techniques, including power, colour and spectral Doppler, has greatly increased in rheumatology in recent years. This is due to the ability of Doppler US (DUS) to detect pathological vascularization within joints and periarticular soft tissues, thereby demonstrating the presence of active inflammation, which has been reported to be correlated with the local neo-angiogenesis. In synovitis, DUS showed a high correlation with histological and MRI findings, thus it is considered a valid tool to detect pathological synovial vascularization. Moreover, it is more sensitive than clinical examination in detecting active joint inflammation and in the evaluation of response to treatment. In addition, DUS may be considered as a reference imaging modality in the assessment of enthesitis, MRI being not sensitive and histology not feasible. Moreover, it has been demonstrated to be able to detect changes in asymptomatic enthesis. In conclusion, DUS is a useful and sensitive tool in the evaluation and monitoring of active inflammation. Its widespread use in clinical rheumatological practice is recommended. The aim of this article is to review the current literature about the role of DUS in rheumatic diseases, analysing its validity, reliability and feasibility. 相似文献
37.
Mihai Popescu Valentin Titus Grigorean Crina Julieta Sinescu Cristian Dumitru Lupascu George Popescu Aurelia Mihaela Sandu Iancu Emil Plesea 《Neurologia medico-chirurgica》2013,53(12):890-895
Cavernous haemangioma (cavernoma) is a benign vascular lesion, exceptionally located in cauda equina. We report a case, diagnosed and operated in the Department of Neurosurgery from Pitesti County Emergency Hospital, of a 60-year-old woman with history of lumbar region distress, who presented with low back pain, paravertebral muscle contracture, and bilateral lumbar radiculopathy, with sudden onset after lifting effort. The preoperative diagnosis was done using computed tomography (CT) and magnetic resonance imaging (MRI), and the patient underwent surgery—two level laminectomy, dural incision, and tumor dissection from the cauda equina nerve roots under operatory microscope. Histopathological examination confirmed the positive diagnosis of cavernoma of cauda equina. The patient''s outcome was favorable, without postoperative neurological deficits. 相似文献
38.
Annette Lennerling Charlotte Lovén Frank JMF Dor Frederike Ambagtsheer Nathalie Duerinckx Mihaela Frunza Assya Pascalev Willij Zuidema Willem Weimar Fabienne Dobbels 《Transplant international》2013,26(2):145-153
In Europe, living organ donation (LOD) is increasingly accepted as a valuable solution to overcome the organ shortage. However, considerable differences exist between European countries regarding frequency, practices and acceptance of donor–recipient relations. As a response, the Coordination Action project ‘Living Organ Donation in Europe’ ( www.eulod.eu ), funded by the Seventh Framework Programme of the European Commission, was initiated. Transplant professionals from 331 European kidney and liver transplant centres were invited to complete an online survey on living kidney donation (LKD) and living liver donation (LLD). In total, 113 kidney transplant centres from 40 countries and 39 liver transplant centres from 24 countries responded. 96.5% and 71.8% performed LKD and LLD respectively. The content of the medical screening of donors was similar, but criteria for donor acceptance varied. Few absolute contraindications for donation existed. The reimbursement policies diverged and the majority of the donors did not get reimbursed for their income loss during recovery. Large discrepancies were found between geographical European regions (the Eastern, the Mediterranean and the North‐Western). As a result of this survey we suggest several recommendations to improve quality and safety of LOD in Europe. 相似文献
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Dabija-Wolter G Sapkota D Cimpan MR Neppelberg E Bakken V Costea DE 《Archives of oral biology》2012,57(4):344-351
ObjectiveFusobacterium nucleatum is an opportunistic pathogen with a key role in subgingival plaque formation and it is found in increased numbers in periodontally affected sites. This study aimed to investigate the potential of F. nucleatum to penetrate and induce alterations in an in vitro reconstructed human gingival mucosa model.MethodsThree-dimensional (3D) organotypic models of human gingiva were engineered using primary gingival keratinocytes and fibroblasts. The reconstructed tissues were challenged with four different strains of fluorescently labelled F. nucleatum in suspension placed on top of epithelial layers. Confocal laser scanning was used to assess the presence of fusobacteria through the organotypic model. Apoptosis (cleaved caspase-3) and cell proliferation (Ki-67) were evaluated by the use of immunohistochemistry in 3D-tissue models. Quantitative real-time PCR was performed to investigate the mRNA expression for MMP-13 and E-cadherin in both 3D-tissues and monolayers.ResultsF. nucleatum invaded the superficial epithelial layers of gingival 3D-tissue models. Challenged tissues showed accentuated shedding of superficial layers and increased number of cleaved caspase-3 and Ki-67 positive cells than controls, although not statistically significant. Levels of E-cadherin and MMP-13 mRNA were not significantly perturbed in multilayer culture. A variable and disproportionate response of MMP-13 mRNA level resulted in challenged primary keratinocytes in monolayers, compared to multilayer culture.ConclusionThese results indicate that F. nucleatum is able to invade superficially a differentiated, stratified gingival epithelium in vitro and triggers the efficient elimination of bacterial infection through epithelial shredding without causing a permanent damage of the tissue. 相似文献