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排序方式: 共有347条查询结果,搜索用时 15 毫秒
191.
192.
Marine sponges are ancient, sessile, filter-feeding metazoans, which represent a significant component of the benthic communities throughout the world. Sponges harbor a remarkable diversity of bacteria, however, little is known about the functional properties of such bacterial symbionts. In this study, we present the genomic and functional characterization of an uncultured δ-proteobacterium associated with the sponge Cymbastela concentrica. We show that this organism represents a novel phylogenetic clade and propose that it lives in association with a cyanobacterium. We also provide an overview of the predicted functional and ecological properties of this δ-proteobacterium, and discuss its complex interactions with surrounding cells and milieu, including traits of cell attachment, nutrient transport and protein–protein interactions. 相似文献
193.
Eight dinucleotide microsatellite markers were developed on Hymeniacidon sinapium (Porifera: Demospongiae), common littoral sponge around Japan, to investigate population genetic structure. Two to 10 alleles were identified in an analysis of 24 individuals of H. sinapium, with observed heterozygosity ranging from 0.04 to 0.83. All loci did not deviate from the Hardy–Weinberg expectations; however, significant linkage disequilibrium between Sinp126 and Sinp142 was found. 相似文献
194.
Yuhan Chen Baoying Yuan Genwen Chen Li Zhang Yuan Zhuang Hao Niu Zhaochong Zeng 《Journal of cellular physiology》2020,235(11):8270-8282
The role of circular RNA (circRNA) in radiation-induced liver disease (RILD) remains largely unknown. In this study, Ras-related C3 botulinum toxin substrate 1 (RAC1) was elevated in irradiated human hepatic stellate cell (HSC) line LX2, the important effector cell mediating RILD. Overexpression of RAC1 promotes cell proliferation, proinflammatory cytokines production, and α-smooth muscle actin expression, which were blocked by microRNA (miR)-146a-5p mimics. CircRNA RSF1 (circRSF1) was upregulated in irradiated LX2 cells and predicted to harbor binding site for miR-146a-5p. Biotinylated-RNA pull down and dual-luciferase reporter detection confirmed the direct interaction of circRSF1 and miR-146a-5p. Enforced expression of circRSF1 increased RAC1 expression by acting as miR-146a-5p sponge to inhibit miR-146a-5p activity, and thus enhanced the cell viability, and promoted inflammatory and fibrotic phenotype of irradiated LX2 cells. These findings indicate a functional regulatory axis composing of circRSF1, miR-146a-5p, and RAC1 in irradiated HSC, which may provide attractive therapeutic targets for RILD. 相似文献
195.
196.
Wilson Rodríguez Oscar Osorno Freddy A. Ramos Carmenza Duque Sven Zea 《Biochemical Systematics and Ecology》2010
The fatty acid composition of whole phospholipids from marine sponges collected from the Colombian Caribbean Sea was determined as part of our studies on the order Halichondrida: Halichondria magniconulosa, Halichondria lutea, Petromica ciocalyptoides, Axinyssa ambrosia, Didiscus oxeata and Dragmaxia undata. Structure elucidation was accomplished by means of gas chromatography retention parameters and GCMS. Eight new fatty acids were identified by their methyl esters and N-acylpyrrolidide derivatives (i.e. 5-methyl-6-octadecenoic, 16-methyl-11-heptadecenoic, 8-methyl-4-tetracosenoic, 8,17-dimethyl-5-octadecenoic, 23-methyl-8-tetracosenoic, 20-methyl-18-tetracosenoic, 4,17-tetracosadienoic and 22,27-dimethyl-5,9-octacosadienoic acids). These findings establish alternative fatty acid biosynthetic possibilities for these organisms. 相似文献
197.
口腔黏膜白色海绵状斑痣为口腔黏膜常染色体显性遗传病,致病基因一般是细胞角蛋白K4及K13的基因突变。近年来不断有新的病例报道并发现新的突变位点。本文就口腔黏膜白色海绵状斑痣临床病理表现,遗传学研究,其动物模型现状及治疗预后做一综述。 相似文献
198.
A total of seven microsatellites out of 88 isolated from a genomic library enriched for (CA)n and (GA)n repeats were characterized in the Mediterranean marine sponge Scopalina lophyropoda. The microsatellite motifs were large (34.81 ± 13.9 bp) and imperfect. The seven microsatellite loci were screened in 30 individuals collected from Blanes, northwestern Mediterranean. All of them were polymorphic (allele numbers and observed heterozygosities ranged from 3 to 6 and from 0.16 to 0.76, respectively). No significant linkage disequilibrium between pairs of loci and no departure from Hardy–Weinberg equilibrium were found. These markers are therefore promising for studies of the population structure of the species. 相似文献
199.
200.
Young-Kwon Seo Hee-Hun Youn Chang-Seo Park Kye-Yong Song Jung-Keug Park 《Biotechnology and Bioprocess Engineering》2008,13(6):745-751
In this work, a novel type of composite scaffold was designed, which has the suitability of both high biocompatibility and
strong mechanical properties, for use in bioartificial dermis applications. The reinforced scaffold consisted of a lyophilized
collagen sponge formed around a cross-linked collagen meshwork with an average thread diameter of approximately 55 μm. Fibroblasts
were cultured in the reinforced collagen sponge for 7 days, during which time the pores in the sponge became filled with cells
that secreted extracellular matrix (ECM) to form a bioartificial dermis. Results of ultimate tensile strength (UTS) measurements
and compression tests indicated that the bioartificial dermis formed around the reinforced collagen sponge showed about ten
times the strength of the bioartificial dermis formed around a typical collagen sponge (1.5 ± 0.05 vs. 0.15 ± 0.05 and 2.5
± 0.1 vs. 0.2 ± 0.08 MPa, respectively). As a result, reinforced collagen mesh improved mechanical properties and this technique
will be possible to make stronger scaffolds, not only for artificial skin applications but also various artificial tissues,
such as synthetic cartilage, bone, and blood vessels. 相似文献