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61.
The aim of this study was to investigate the species composition and distribution of fish larvae in relation to hydrographic conditions in the waters surrounding Taiwan Island (TI) in February 2003. In total, 242 kinds of fish larvae belonging to 127 genera and 75 families were recognized. Among these, 109 taxa were identified to the family or genus level, others to the species level. The 12 predominant types, which constituted 71% of the total fish larvae, were Engraulis japonica, Scomber sp., Diaphus spp., Benthosema pterotum, Carangoides ferdau, Embolichthys mitsukurii, Maurolicus sp., unidentified Myctophidae, Gonostoma gracile, Trichiurus lepturus, unidentified Gobiidae, and Myctophum asperum. The distribution of fish larvae showed a clear association with water masses around TI, with higher abundances and lower species richness northwest of TI where the China Coastal Current prevails, and lower abundances and higher species diversity east of TI where the Kuroshio Current dominates. Cluster analysis distinguished three station groups and four species groups, and the distribution patterns of fish larvae also corresponded to hydrographic conditions. The total abundances of fish larvae and eight of the 12 predominant taxa showed significant and positive correlations with zooplankton abundance, which suggests that food source might be a key factor determining the abundance and distribution of fish larvae during the winter.  相似文献   
62.
No specific abnormalities have been reproducibly manifested in aneurally cultured muscle of Duchenne muscular dystrophy (DMD) patients. We now report that the accumulation of the muscle-"specific" isozyme of creatine kinase (CK-MM) was significantly and preferentially impaired in long-term innervated contracting muscle fibers cultured from 4 DMD patients (DMD-InnCMFs) compared to: i) their noninnervated sister-cultured muscle fibers, and ii) innervated contracting control cultured human muscle fibers (Control-InnCHMFs). Accumulation of other muscle-"specific" isozymes (MSIs), viz. glycogen phosphorylase, phosphoglycerate mutase, and lactic dehydrogenase, was not significantly impaired. We have not observed preferentially-impaired CK-MM accumulation in any Control-InnCHMFs from 22 patients (children and adults) with a variety of neuromuscular diseases. There was no apparent difference between DMD-InnCMFs and Control InnCHMFs regarding: acceptance of innervation; neuronally-driven, virtually continuous muscle-fiber contractions; characteristic myofiber organization by phase-contrast microscopy, and increased longevity of the innervated fibers.  相似文献   
63.
Hydrophobic anion exchangers were formed by cobonding both ionic and hydrophobic ligands to silica gel. These phases were used to separate single-stranded oligonucleotides and double-stranded DNA restriction fragments. By varying the ratio of n-octyldimethylsilane and either 3-chloropropyldimethylsilane or 4-chlorobutyldimethylsilane added during silanization a series of mixed-ligand or mixed-mode stationary phases was created. Concentration and ratio of bonded ligands were determined using a new gas chromatography fluorination method. Total ligand coverage was found to approach 2.1 ligands nm-2 for n-octyldimethylsilane. Bonding reproducibility for mixed-mode phases was good. Nucleic acid separations were achieved under gentle mobile phase conditions by using the stationary phase as an easily modifiable variable.  相似文献   
64.
Induced pluripotent stem (iPS) cell research has been growing a new height throughout the world due to its potentialities in medical applications. We can explore several therapeutic applications through the iPS cell research. In this review, we have first discussed the development of iPS cells, reprogramming factors, and effectiveness of iPS cells. Then we have emphasized the potential applications of iPS cells in pharmaceutical and medical sectors, such as, study of cellular mechanisms for spectrum of disease entities, disease-specific iPS cell lines for drugs discovery and development, toxicological studies of drugs development, personalized medicine, and regenerative medicine.  相似文献   
65.
CCL5 (previously called RANTES) is in the CC‐chemokine family and plays a crucial role in the migration and metastasis of human cancer cells. On the other hand, the effect of CCL5 is mediated via CCR receptor. RT‐PCR and flow cytometry studies demonstrated CCR5 but not CCR1 and CCR3 mRNA in oral cancer cell lines, especially higher in those with high invasiveness (SCC4) as compared with lower levels in HSC3 cells and SCC9 cells. Stimulation of oral cancer cells with CCL5 directly increased the migration and metalloproteinase‐9 (MMP‐9) production. MMP‐9 small interfering RNA inhibited the CCL5‐induced MMP‐9 expression and thereby significantly inhibited the CCL5‐induced cell migration. Activations of phospholipase C (PLC), protein kinase Cδ (PKCδ), and NF‐κB pathways after CCL5 treatment was demonstrated, and CCL5‐induced expression of MMP‐9 and migration activity was inhibited by the specific inhibitor of PLC, PKCδ, and NF‐κB cascades. In addition, migration‐prone sublines demonstrate that cells with increasing migration ability had more expression of MMP‐9, CCL5, and CCR5. Taken together, these results indicate that CCL5/CCR5 axis enhanced migration of oral cancer cells through the increase of MMP‐9 production. J. Cell. Physiol. 220: 418–426, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
66.
The intracellular transport of soluble lysosomal enzymes relies on the post-translational modification of N-linked oligosaccharides to generate mannose 6-phosphate (Man 6-P) residues. In most cell types the Man 6-P signal is rapidly removed after targeting of the precursor proteins from the Golgi to lysosomes via interactions with Man 6-phosphate receptors. However, in brain, the steady state proportion of lysosomal enzymes containing Man 6-P is considerably higher than in other tissues. As a first step toward understanding the mechanism and biological significance of this observation, we analyzed the subcellular localization of the rat brain Man 6-P glycoproteins by combining biochemical and morphological approaches. The brain Man 6-P glycoproteins are predominantly localized in neuronal lysosomes with no evidence for a steady state localization in nonlysosomal or prelysosomal compartments. This contrasts with the clear endosome-like localization of the low steady state proportion of mannose-6-phosphorylated lysosomal enzymes in liver. It therefore seems likely that the observed high percentage of phosphorylated species in brain is a consequence of the accumulation of lysosomal enzymes in a neuronal lysosome that does not fully dephosphorylate the Man 6-P moieties.  相似文献   
67.
Attenuated antioxidant activities, irregular cytokines expressions and reduced regulatory T cells, are strongly associated with the pathogenesis of systemic lupus erythematosus (SLE). Despite the well‐established beneficial effects of cystamine on lupus‐prone mice, the extent to which cystamine contributes to antioxidant activity and the reduction of regulatory T cells has seldom been investigated. Therefore, this study elucidates how cystamine affects anti‐oxidant activities in NZB/W F1 mice by performing assays of Glutathione (GSH), 1,1‐diphenyl‐2‐ picryl‐hydrazyl (DPPH) and malondialdehyde thiobarbituric acid (MDA). In addition, investigations of the effects of cystamine on CD4+/CD25+ regulatory T cells and interleukin‐6 (IL6)/STAT‐3 signalling were performed with flow cytometry and immunoblots. Experimental results reveal more significantly reduced MDA and increased GSH and DPPH in NZB/W F1 mice receiving cystamine than in those mice receiving PBS. Meanwhile, CD4+/CD25+ regulatory T cells more significantly increase in NZB/W F1 mice receiving cystamine than in those mice receiving PBS, accompanied by significantly reduced IL‐6/phosphorylated STAT‐3 expression. The above findings suggest the beneficial effects of cystamine in terms of increasing antioxidant activities and CD4+/CD25+ regulatory T cells in lupus‐prone mice by suppressing IL‐6/STAT3 signalling.  相似文献   
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