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811.
采后热空气处理对金冠苹果后熟衰老及病害的影响 总被引:2,自引:1,他引:2
金冠苹果采用38℃,72h或96h热空气处理,可降低0℃贮藏中果实的呼吸强度和乙烯释放量,延缓非溶性果胶的降解,维持较高的硬度、脆度,同时也会加速果皮的褪绿变黄和固酸比的上升,尤其是38℃96h处理的作用效果更为明显,显著提高了货架期后(20℃7d)苹果的质地品质和可接受程度,延缓衰老。苹果分别接种扩展青霉、灰葡萄孢霉,0℃和20℃条件下其病害发生率和腐烂均很严重,采用38℃96h热空气处理可以完全控制病害的发生,避免腐烂。可见,热空气处理一方面能延缓金冠苹果的后熟衰老,另一方面还能控制贮期病害的发生。 相似文献
812.
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815.
大脑皮质神经元培养中胰蛋白酶消化分离技术的探讨 总被引:1,自引:0,他引:1
为探讨大脑皮质神经元培养中胰蛋白酶消化分离法的最佳条件, 取新生大鼠大脑皮质组织,在不同的胰蛋白酶消化条件下分离培养神经元,通过细胞形态观察以及染色计数比较不同消化条件对神经元活性的影响。结果表明,0.25%胰蛋白酶,37℃,5 min消化分离的神经元活性较好,细胞产率也较高。在新生大鼠大脑皮质神经元培养时,采用0.25%胰蛋白酶,37℃,5 min可消化分离到单层、生长活性较好的神经元。 相似文献
816.
根据已报道的哺乳动物朊病毒基因序列设计引物,采用PCR方法扩增了25只东北虎的朊病毒基因,克隆、测序及序列分析表明,所得到的东北虎朊病毒基因片段为402bp,编码134个氨基酸的前体蛋白,核苷酸序列同源性为99.67%。共发现了4个核苷酸多态性(T423C,A501G,C511A,A610G),其中C511A和A610G的碱基突变导致K171Q和A204T氨基酸的变异。与已报道的猫、貂、绵羊、鼠和犬等哺乳动物的氨基酸序列比较,结果与猫(AF003087,97.3%)和绵羊(97.3%)的氨基酸同源性最高。 相似文献
817.
AIM: Cinnamyl aldehyde (CA) is one alcohol ingredient derived from Cinnamomum cassia,which is widely used in treating chronic skin wound in Chinese medicine with the curative effect of ‘rescuing YANG’.The purpose of the present study was to investigate the expression of c-Fos,c-Myc proteins at different time points in NIH3T3 treated with CA and explore the possible mechanism of promoting cell proliferation by CA.METHODS: MTT assay was used for observing cell proliferation.Expression of c-Fos and c-Myc proteins in NIH3T3 cells were assessed by immunocytochemistry assay.RESULTS: The cell proliferation was promoted obviously when CA concentration was between 8.8×10-2 μg/L and 8.8×10 μg/L.CA at concentration of 5.5 μg/L significantly induced expression of c-Fos,c-Myc proteins at 2-3 h after the stimulation compared with control group (P<0.01).CONCLUSION: CA increases expression of c-Fos and c-Myc proteins,which may be one of mechanisms for CA to promote NIH3T3 cell proliferation. 相似文献
818.
AIM: To investigate the influence of GM-CSF on human vascular endothelial cells induced to form new blood vessels and the role of VEGF. METHODS: HUVECs were cultured by Matrigel to set up a stable angiogenesis system with the stimulating factors. The rhGM-CSF concentration-dependent and time-dependent effects and the role of VEGF165 were detected. CD34 was measured by immunochemical staining and numbers of vessel formation was calculated under microscopic observation. RESULTS: After treatment with rhGM-CSF at various concentrations and at different time points, the numbers of vessel formation increased in a dose-dependent and time-dependent manner. In the presence of VEGF165, the numbers of vessel formation increased evidently. CONCLUSION: HUVECs were induced to develop tubular structure in vitro cultured with Matrigel. GM-CSF promotes human vascular endothelial cells to form vessel-like structure in vitro in a dose-dependent and time-dependent manner. VEGF also in vitro promotes human vascular endothelial cells to form new vessel-like structure. 相似文献
819.
MOU Bo YANG Zhi-hong ZHAO Jia-wei WANG Xuan-chun DONG Xue-hong LIU Yu HU Ren-ming 《园艺学报》2007,23(5):888-892
AIM: To verify and localize the expression of nicotinamide N-methyltransferase (NNMT) in pancreas of streptozotocin(STZ)-induced diabetic monkeys and understand its important role in β-cell destruction in the pathogenesis of diabetes. METHODS: Through an olig-microarray gene chip, NNMT was identified as the most obviously up-regulated genes in pancreas of STZ-induced diabetic monkeys versus controls. Semiquantitative RT-PCR and Western blotting were performed to verify the differential expression at mRNA and protein level respectively. Then the cellular localization of NNMT expression within pancreas was identified by immunohistochemical(IHC) staining.RESULTS: An obvious high expression of NNMT at both mRNA and protein levels was shown in pancreas of STZ-induced diabetic monkeys compared to that of controls. Further localization of the protein by IHC staining in pancreas specimens showed that its altered expression was restricted to central islets, most of which were β cells.CONCLUSION: Expression of NNMT is increased in islets of STZ- induced diabetic monkeys, which infers that NNMT might participate in the process of β cell damage in diabetes probably through the mechanism of energy metabolism disturbance. 相似文献
820.
AIM: To investigate the activation of nuclear factor κB (NF-κB) induced by lipopolysaccharides (LPS) in rat alveolar macrophages (AMs) and its regulatory role in tumor necrosis factor (TNF-α) secretion. METHODS: The dynamic activity changes of NF-κB induced by LPS were determined with electrophoretic mobility shift assay (EMSA). Antisense oligonucleotides of NF-κB subunit (p65) were transfected into AMs prior to LPS stimulation. The effect of antisense oligonucleotide transfection on expressions of p65 and TNF-α in supernatant were measured with Western blotting and enzyme linked immunosorbent assay (ELISA), respectively.RESULTS: NF-κB activity increased markedly and reached its peak level at 4 h after LPS stimulation. After transfected with antisense oligonucleotides of NF-κB subunit (p65), expression of p65 and TNF-α in supernatant decreased markedly.CONCLUSION: NF-κB activity has a positive effect on regulating secretion of TNF-α in AMs induced by LPS. 相似文献