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1.
In this study, the effect of fibronectin on the neurite outgrowth from embryoid bodies (EBs) in neurodifferentiated embryonal carcinoma P19 cells was examined. The neurite outgrowth on fibronectin was maintained for a longer time in comparison with those on collagen or laminin. Quantitative RT-PCR revealed that mRNA level corresponding to sonic hedgehog (Shh) in neurodifferentiated P19 cells was upregulated on fibronectin, whereas collagen or laminin did not affect. Further knockdown of integrin αv subunit in P19 cells demonstrated that expression of Shh was mediated through interaction between fibronectin and integrin. Additionally, exogenous Shh agonist accelerated neurite outgrowth from embryonic stem cell-derived EBs without large change of neuronal phenotype expression. Taken together, fibronectin could maintain neurite outgrowth via increased Shh expression.  相似文献   
2.
Ichimi  Kazuhiko  Honda  Miyuki  Okada  Yuka  Tsuzuki  Kana  Yamaguchi  Hitomi 《Fisheries Science》2019,85(3):417-427
Fisheries Science - We carried out surveys to clarify how the density (no. of individuals/m2) and condition factor (CF) of Manila clam Ruditapes philippinarum differ between estuarine tidal flats...  相似文献   
3.
To elucidate the formation mechanism of acidsoluble lignin (ASL) formed in the Klason lignin determination, beech wood meals were treated with sulfuric acid (SA) under various conditions, and the ASL solution was extracted with CHC13. The results indicated the following: (1) wood components yielding ASL are dissolved in 72% SA during the initial stage; (2) the quantity of ASL is highest during the initial stage, then decreases with prolonged time of 72% SA treatment and finally reaches a constant value; (3) soluble lignin prepared by 72% SA treatment and subsequent standing in 3% SA again yield insoluble Klason lignin and ASL after boiling in 3% SA; and (4) about half the amount of ASL is dissolved in CHC13. The foregoing suggest that wood components yielding ASL are dissolved in 72% SA at the beginning and finally change to ASL after being subjected to depolymerization, hydrolysis, and other reactions. ASL may thus be composed of low-molecular-weight degradation products and hydrophilic derivatives of lignin.  相似文献   
4.
5.
  • ? For assessing forest thinning effects at large (i.e. continental) scale, data scarcity and technical limitations prevent the application of localized or individual-based thinning models.
  • ? Here we present a simple general framework to analyze and predict the effects of thinning on growth and mortality, including the following stand density development. The effects are modeled in relative terms so that the model can be parameterized based on any thinning experiment that includes an unthinned control, regardless of site conditions and stand age.
  • ? The model was tested against observed thinning effects on growth and mortality from five temperate and boreal species (all species pooled r 2 = 0.51). It predicted a maximum increase in net stem biomass increment of 16% and a reduction in density-related mortality of 75% compared to un-thinned conditions at stand densities of around 70% of the maximum (increment optimal density).
  • ? A sensitivity analysis revealed overlapping ranges of near optimal density (net increment within 95% of optimal) among all tested species, suggesting that one thinning scenario can be used for many species. The simple and general formulation of thinning effects based on only five parameters allows easy integration with a wide range of generic forest growth models.
  •   相似文献   
    6.
    A total of 318 Escherichia coli isolates obtained from different food-producing animals affected with colibacillosis between 2001 and 2006 were subjected to phylogenetic analysis: 72 bovine isolates, 89 poultry isolates and 157 porcine isolates. Overall, the phylogenetic group A was predominant in isolates from cattle (36/72, 50%) and pigs (101/157, 64.3%) whereas groups A (44/89, 49.4%) and D (40/89, 44.9%) were predominant in isolates from poultry. In addition, group B2 was not found among diseased food-producing animals except for a poultry isolate. Thus, the phylogenetic group distribution of E. coli from diseased animals was different by animal species. Among the 318 isolates, cefazolin resistance (minimum inhibitory concentrations: ≥32 μg/ml) was found in six bovine isolates, 29 poultry isolates and three porcine isolates. Of them, 11 isolates (nine from poultry and two from cattle) produced extended spectrum β-lactamase (ESBL). The two bovine isolates produced blaCTX-M-2, while the nine poultry isolates produced blaCTX-M-25 (4), blaSHV-2 (3), blaCTX-M-15 (1) and blaCTX-M-2 (1). Thus, our results showed that several types of ESBL were identified and three types of β-lactamase (SHV-2, CTX-M-25 and CTX-M-15) were observed for the first time in E. coli from diseased animals in Japan.  相似文献   
    7.
    Characterization of CTLA-4, PD-1 and PDL-1 genes from swamp and riverine type water buffaloes was done by molecular cloning, sequencing and phylogenetic analysis. The cloned cDNA of CTLA-4, PD-1 and PDL-1 contained an open reading frame of 666, 849 and 870 nucleotides, encoding a polypeptide of 221, 282 and 298 amino acids, respectively. Nucleotide sequence homology of both CTLA-4 and PDL-1 had 99.8% in swamp and riverine type, which gives the identical polypeptide. Meanwhile, PD-1 genes of swamp and riverine type water buffaloes had 99.2% of homology in nucleotide sequence, which has substitution of two amino acid residues. The hexapeptide motif, phosphatidylinositol 3′-kinase and potential glycosylation sites were conserved within the tribe Bovinae. Phylogenetic analysis confirmed the degree of relationship between the bubaline species and justify the distinctness of each breeds by the bootstrap value generated.  相似文献   
    8.
    Strains of the Japanese pear pathotype of Alternaria alternata were screened for double-stranded RNAs (dsRNAs). Four strains had several dsRNAs; strain N18 was associated with several dsRNAs and had impaired growth phenotypes such as irregular mycelium and abnormal pigmentation. We isolated dsRNA-cured isolates from strain N18 by single-conidium isolation. The dsRNA-cured isolates had recovered normal growth and pigmentation. Enlarged vesicles were observed in mycelial cells of the original dsRNA-carrying N18 strain. DAPI nuclear staining revealed regression of the nuclei in dsRNA-carrying N18 cells. These results indicate that the dsRNAs might have negative effects, such as apoptosis-like cell death, on the host fungus.  相似文献   
    9.
    Severe blight of potted seedlings of monkshood caused by Plectosporium tabacinum was found in glasshouses in Kagawa Prefecture in southwest Japan in May 2001. Root rot and browning of stem bases were followed by wilting and yellowing of leaves, then blighting of leaves, flower buds and stems. A fungus was isolated from diseased plants and confirmed to cause the disease. The new disease was named “Plectosporium blight of monkshood”.  相似文献   
    10.
    The effect of the Maillard reaction on the allergenicity of squid tropomyosin (TM) was investigated. When TM was reacted with ribose (TM-ribose), its human-specific IgE-binding ability decreased markedly and alpha-chymotryptic digestibility of TM was also altered at the early stage of the Maillard reaction. On the other hand, the modification of the lysine residues in TM using 2,4,6-trinitrobenzenesulfonic acid had no effect on the allergenicity and alpha-chymotryptic digestibility of TM. Therefore, the structural change in TM induced by the Maillard reaction would cause the reduction of the allergenicity, rather than the block of lysine residues. Although peptic digestion diminished the specific IgE-binding ability of TM, the reduction of the allergenicity by the Maillard reaction remained after peptic digestion. These results suggest that hypersensitive reaction of TM-ribose in the human body might be lower than that of native TM.  相似文献   
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