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51.
Jianyong Wu 《Cytotechnology》1996,22(1-3):103-109
Animal cells in suspension culture can suffer severe mechanical damage from bursting gas bubbles or other hydrodynamic force sources. Certain chemical additives in the culture media, particularly some surface-active chemicals, can effectively protect animal cells against such damage. Previously we proposed that the protective effect is associated with the adsorption of the additives in the cell membrane through hydrophobic binding of the surface-active molecules to the membrane. Adsorption of the additives to the cell membrane may lead to decreased hydrophobicity of the cell surface, thus eliminating cell adhesion to bubbles and reducing cell damage from bursting bubbles. In this study, we measured the hydrophobicity of two insect cell lines based on cell adhesion to hydrocarbon phase and its influence by surface-active chemicals, Pluronic F68, a methylcellulose and a polyethylene glycol. The experimental results showed strong support for the aforecited cell protection mechanism.  相似文献   
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Journal of Plant Growth Regulation - With the increasing popularity of urban landscaping, there is a greater need to address iron deficiency and chlorosis in Cinnamomum camphora. Beneficial...  相似文献   
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RIG-1 signalling is responsible for the detection of cytoplasmic viral RNA molecules. DEXH (Asp-Glu-X-His) box polypeptide 58 (encoded by DHX58) is a negative regulator of the RIG-1 signalling pathway. In human, the DHX58 gene can be upregulated and can inhibit the RIG-1 signalling pathway during viral infection. In this study, porcine DHX58 gene expression patterns were studied. According to our results, the porcine DHX58 gene was upregulated not only by the stimulation of Poly I:C but also by the stimulation of 1ipopolysaccharides (LPS). One polymorphism (g.4919G>C), detected in the ninth intron, was significantly associated with some blood parameters including the red cell distribution width of 1-day-old pigs and white blood cell counts, lymphocyte absolute counts, and platelet distribution width of 17-day-old pigs (P < 0.05). Moreover, the individuals with the genotype GG have a significantly higher mean white blood cell count than individuals with genotype CC or GC (P < 0.05). Our study indicates that DHX58 is an important gene that is associated with the immune response in swine.  相似文献   
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M C Wu  M R Zaun  F M Wu 《FEBS letters》1989,244(2):338-342
Inhibitors of ADP-ribosylation inhibited the myeloid differentiation of murine myelomonocytic leukemia, WEHI-3BD+ cells induced by granulocyte colony-stimulating factor. Benzamide, at 2.0 mM, inhibited 50% of the WEHI-3BD+ cell differentiation but had no significant effect on the proliferation. However, benzylaminododecylguanine hydrochloride and p-methoxylbenzylaminodecamethylene guanidine sulfate at 2.0 and 2.2 microM, respectively, inhibited 50% of proliferation but had no effect at all on differentiation. The differential effects of inhibitors provide a model to study the role of ADP-ribosylation in myeloid differentiation.  相似文献   
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