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Neurons and gla from the central nervous system of the adult teleost Carassius auratus have been grown as explant cultures of minced brain tissue and as trypsin dissociated cells. These cultures exhibit extensive neurite growth from two neuronal types, have organotypic ultrastructure, and contain electrically active cells. Autoradiographic data indicate that these neurons do not divide in culture, and histological evidence suggests that some mature neurons survive explantation and regenerate processes. However, explantation of brain fragments not containing undifferentiated cells, localized in the ventricular and subventricular zones in the brains of fish, resulted in mesenchymal and glial cell cultures only. Therefore, a contribution to the population of cells in culture by undifferentiated cells must be considered. The cultured neurons remained viable for at least 19 weeks and ultrastructural and electrophysiological data indicate synaptic interaction between cells in explant cultures. 相似文献
235.
Ben S. Cooper Maciej F. Boni Wirichada Pan-ngum Nicholas P. J. Day Peter W. Horby Piero Olliaro Trudie Lang Nicholas J. White Lisa J. White John Whitehead 《PLoS medicine》2015,12(4)
BackgroundExperimental treatments for Ebola virus disease (EVD) might reduce EVD mortality. There is uncertainty about the ability of different clinical trial designs to identify effective treatments, and about the feasibility of implementing individually randomised controlled trials during an Ebola epidemic.ConclusionsThe MSA discards ineffective treatments quickly, while reliably providing evidence concerning effective treatments. The MSA is appropriate for the clinical evaluation of EVD treatments. 相似文献
236.
In the Adriatic Sea, the correlation between mucilage phenomena and the presence of Gonyaulax fragilis (Schütt) Kofoid (Dinophyta) has been recently demonstrated. The application of PCR-based methods and the development of species-specific
molecular probes might represent powerful technologies for rapid and specific monitoring of microalgal species in seawater
samples. Here, we report sequencing of the small subunit (SSU) ribosomal RNA gene (18S rDNA) of G. fragilis and its comparative analysis within the Dinophyta. Total DNAs were extracted and amplified from cultured cells of G. fragilis, which were isolated from natural phytoplanktonic association in the northern Adriatic Sea. Total 18S rDNA gene was amplified
using 16S1N and 16S2N primers and sequenced using ad hoc designed internal primers. The primers amplified a product of expected size (length 1700/1800 bp). The phylogenetic analysis
carried out by comparing G. fragilis sequence to homologous sequences of Lingulodinium polyedrum (Stein) Dodge, Gonyaulax spinifera (Claparède et Lachmann) Diesing, Protoceratium reticulatum (Claparède et Lachmann) Bütschli revealed a great nucleotide divergence of G. fragilis SSU sequence. Therefore, the SSU sequence could be used as species-specific marker for the identification of this mucilage
producer microalga. In addition, such sequence could be used as target to design oligonucleotide probes for the construction
of DNA microchips as diagnostic tool for the routine monitoring of harmful algae in seawater.
An erratum to this article is available at . 相似文献