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1.
Four species of icefishes were sampled in the Yellow River estuary of the Bohai Sea from April 1984 to April 1985 and from February 1988 to June 1989. Morphological analysis showed that they belonged to three subfamilies of Salangidae: one species from Protosalangicae, Protosalanx chinensis ; two species from Salanginae, Salanx ariakensis and Salanx prognathus ; and one species, Neosalanx andersoni , from Salangichthyinae, a new subfamily. External morphological characteristics, population composition, growth, maturity, food habits, longevity, fecundity, abundance and distribution of these icefishes are described. Based on these analyses, a clear outline of taxonomy, zoogeography aod biology of icefishes in the Yellow River estuary of the Bohai Sea was established.  相似文献   
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Ocular angiogenesis, characterized by the formation of new blood vessels in the avascular area in eyes, is a highly coordinated process involved in retinal vasculature formation and several ocular diseases such as age-related macular degeneration, proliferative diabetic retinopathy and retinopathy of prematurity. This process is orchestrated by complicated cellular interactions and vascular growth factors, during which endothelial cells acquire heterogeneous phenotypes and distinct cellular destinations. To date, while the vascular endothelial growth factor has been identified as the most critical angiogenic agent with a remarkable therapeutic value, the Notch signaling pathway appears to be a similarly important regulator in several angiogenic steps. Recent progress has highlighted the involvement, mechanisms and therapeutic potential of Notch signaling in retinal vasculature development and pathological angiogenesis-related eye disorders, which may cause irreversible blindness.  相似文献   
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骨髓间充质干细胞分化为胰岛细胞治疗糖尿病   总被引:1,自引:0,他引:1  
糖尿病已成为严重危害人类健康的疾病之一。目前,移植胰岛治疗糖尿病已初见疗效,但由于胰岛来源匮乏和免疫排斥反应而受阻。骨髓间充质干细胞(bonemarrowmesenchymalstemcells,BMMSCs)取材方便,容易进行体外分离、培养和纯化,且具有跨越分化潜能。若将自体BMMSCs诱导分化为胰岛细胞,可望解决细胞来源和免疫排除问题,实现糖尿病的自体细胞治疗。现对体外诱导BMMSCs分化为胰岛细胞治疗糖尿病的研究进展进行综述,并指出了存在问题和今后的研究方向。  相似文献   
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Trichoderma harzianum is a plant-beneficial fungus that secretes small cysteine-rich proteins that induce plant defense responses; however, the molecular mechanism involved in this induction is largely unknown.Here, we report that the class II hydrophobin Th Hyd1 acts as an elicitor of induced systemic resistance(ISR) in plants. Immunogold labeling and immunofluorescence revealed Th Hyd1 localized on maize(Zea mays) root cell plasma membranes. To identify host plant protein interactors of Hyd1, we screened a maize B73 root c DNA library. Th Hyd1 interacted directly with ubiquilin1-like(UBL). Furthermore, the N-terminal fragment of UBL was primarily responsible for binding with Hyd1 and the eight-cysteine amino acid of Hyd1 participated in the protein-protein interactions. Hyd1 from T. harzianum(Thhyd1) and ubl from maize were co-expressed in Arabidopsis thaliana, they synergistically promoted plant resistance against Botrytis cinerea. RNA-sequencing analysis of global gene expression in maize leaves 24 h after spraying with Curvularia lunata spore suspension showed that Thhyd1-induced systemic resistance was primarily associated with brassinosteroid signaling, likely mediated through BAK1. Jasmonate/ethylene(JA/ET)signaling was also involved to some extent in this response. Our results suggest that the Hyd1-UBL axis might play a key role in inducing systemic resistance as a result of Trichoderma-plant interactions.  相似文献   
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ABSTRACT

The octopus Cistopus indicus is an important target of cephalopod fisheries in China. It is widely distributed in the South Pacific and tropical Indian Ocean, from the South China Sea, the Philippines, Malaysia, to Indian and Pakistan seas. We collected specimens from five sites in China and Vietnam (Zhoushan, Wenzhou, Shacheng, Zhanjiang and Mangjie). A fragment of 675bp of cytochrome b (Cytb) was amplified from 95 individuals. A total of 27 haplotypes and 78 variable nucleotide sites was observed. High haplotype diversity and low nucleotide diversity were observed in all populations. The phylogenetic analysis separated these populations into two clades; one was composed of three populations (Zhoushan, Wenzhou and Shacheng), the other of two (Zhanjiang, Mangjie). AMOVA analysis detected that 4.67% of the genetic variation occurred within populations and 95.33% occurred among populations. FST values ranged from 0.014 to 0.993, highlighting the high genetic variation among the populations. Assuming a molecular clock with a rate of 2.15–2.6%/Ma for the Cytb gene, the two clades may have diverged 2.88–3.49 million years ago (Pliocene). Neutral evolution tests and mismatch distribution analysis suggested recent population expansion. The present results revealed valuable information for genetic assessment, management and conservation of this species.  相似文献   
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Litter decomposition, a fundamental process of nutrient cycling and energy flow in freshwater ecosystems, is driven by a diverse array of decomposers. As an important component of the heterotrophic food web, meiofauna can provide a trophic link between leaf‐associated microbes (i.e., bacteria and fungi)/plant detritus and macroinvertebrates, though their contribution to litter decomposition is not well understood. To investigate the role of different decomposer communities in litter decomposition, especially meiofauna, we compared the litter decomposition of three leaf species with different lignin to nitrogen ratios in litter bags with different mesh sizes (0.05, 0.25, and 2 mm) in a forested stream, in China for 78 days. The meiofauna significantly enhanced the decomposition of leaves of high‐and medium‐ quality, while decreasing (negative effect) or increasing (positive effect) the fungal biomass and diversity. Macrofauna and meiofauna together contributed to the decomposition of low‐quality leaf species. The presence of meiofauna and macrofauna triggered different aspects of the microbial community, with their effects on litter decomposition varying as a function of leaf quality. This study reveals that the meiofauna increased the trophic complexity and modulated their interactions with microbes, highlighting the important yet underestimated role of meiofauna in detritus‐based ecosystems.  相似文献   
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