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Ebrahim Zabihi Abbas Soleymani Leila Ghassemi 《Journal of ocular biology, diseases, and informatics》2012,5(1):25-30
As a well-known organophosphate insecticide, diazinon (DZN) has been used for several decades in agriculture. The major signs of ophthalmic toxicity of DZN have been reported to be cholinergic overstimulation (lacrimation, myosis). Here, we report, for the first time, ulcerative keratitis in C57bl/6 mice secondary to sub-acute exposure to DZN. Four groups of female C57bl/6 mice were administered intraperitoneally either DZN (1, 5, 25 mg/kg/day) or vehicle for 14 consecutive days. Then, histopathological examinations on mice eyes were performed using light microscope and scored for corneal keratitis. Furthermore, blood cholinesterase activity, and hematologic examinations were performed. Data indicated a significant ulcerative keratitis with prompt vision loss in mice exposed to 25 and 5 mg/kg/day (P < 0.05) doses. These results suggest that diazinon might induce ulcerative keratitis secondary to its immunosuppresive effects at high doses in C57bl/6 mice. 相似文献
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Zahra Hajihassan Niloofar Khairkhah Farshid Zandsalimi 《Preparative biochemistry & biotechnology》2020,50(2):141-147
AbstractActivin A is a member of the transforming growth factor-beta (TGF-β) protein superfamily, which acts as a hormone in regulating cell proliferation and differentiation. Structurally, activin is a dimer of two subunits linked by a disulfide bond. Since the correct folding of this protein is essential for its function, we aimed to use a modified signal peptide to target the expressed recombinant protein to the periplasm of Escherichia coli as an effective strategy to produce correctly-folded activin A. Therefore, the coding sequence of native Iranian Bacillus licheniformis α-amylase signal peptide was modified and its efficiency was checked by SignalP bioinformatics tool. Then its final sequence was cloned upstream of the activin A mature cDNA. Protein expression was done using 1?mM of isopropyl thio-β-D-galactoside (IPTG) and a post-induction time of 8?hr. Additionally, following purification of recombinant activin A, circular dichroism spectroscopy was used to determine the accuracy of secondary structure of the protein. Importantly, differentiation of K562 cells to the red blood cell was confirmed by measuring the amount of Fe+2 ions after treatment with recombinant activin A. The results indicated that the produced recombinant activin A had the same secondary structure as the commercial human activin A and was fully functional. 相似文献