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AIM: To observe the effects of harvested wound exudate on intracellular free Ca2+ in epidermal stem cells (ESCs) in vitro, and to investigate the relationship between mitogen-activated protein kinases (MAPKs) signal pathways and Ca2+ mobilization in this condition.METHODS: Wound exudate was harvested from the 80 full-thickness wounds produced on both sides of the back in 40 adult Wistar rats. ESCs were isolated, purified from neonatal Wistar rats by referring to the formerly records and binding our ideas. When the cultured cells showed up clone growing, they were divided into five groups as follows: group A: control group (no-treatment); group B: only treatment with wound exudate; group C: treatment with wound exudate and PD98059; group D: treatment with wound exudate and SB203580; group E: treatment with wound exudate, PD 98059 and SB203580. Then, the cells were incubated with fluorescence Ca2+ dye fluo-3/AM at 37 ℃ for 30 min, and measured by using laser scanning confocal microscope.RESULTS: The results showed that the fluorescent intensity of group B was higher than that in group A. A phenomenon of calcium oscillation was found in group C and group D. Furthermore, a rapid decrease of fluorescent intensity was observed in the cells that were preincubated with PD98059 and SB203580 at the same time. CONCLUSION: Based on above results, we propose that wound exudate can directly induce an increase in intracellular free Ca2+concentrations of ESCs. MAPKs signaling pathway has an important function of feedback regulation for free Ca2+ mobilization of ESCs in this condition, and also is capable of affecting the biological behaviour of epidermal stem cells. 相似文献
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在分析工业工程专业特点的基础上,针对工业工程专业工程硕士的特点,提出了新时期对工业工程领域工程硕士研究生培养质量的要求和挑战。结合重庆大学在该方面的人才培养经验。探索在新时期适合工业工程领域工程硕士的人才培养模式。 相似文献
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AIM:To construct the SNP haplotypes and the haplotype blocks of FcαR1 gene in Chinese Han population in Guangdong province.METHODS:Genomic DNA was extracted from 100 healthy Chinese Han subjects.Genotypes of the SNPs in FcαR1 gene were determined by PCR and direct sequencing.Constructing the SNP haplotypes and the haplotype blocks of FcαR1 gene by 12 SNPs that is its minor allele frequency were more than 0.1 with Haploview soft.RESULTS:There are 3 haplotype blocks in FcαR1 gene in Chinese Han population in Guangdong province.The number of haplotypes in each haplotype blocks was from 3 to 7 (average 5.33).However,the number of common haplotypes in each blocks was from 2 to 3 (average 2.3).CONCLUSION:Our results show the existence of the block-like structures and the common haplotypes in each block in FcαR1 gene.It provides a useful tool for the genome research and the mapping of disease contributing genes/variants in this gene. 相似文献
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ZHANG Hui-zhong LI Hai-gang WEI Yi-ping LIU Jin-geng WU Deng CAO Yong-ke WANG Mei 《园艺学报》2006,22(10):2018-2021
AIM: To investigate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and endothelin converting enzymes (ECE) in non-small-cell lung carcinoma (NSCLC), and their relationship with lymphoid metastasis and prognosis.METHODS: Expression of EMMPRIN and ECE in 77 cases of patients with NSCLC was detected immunohistochemically.The relationship of the expression of EMMPRIN and ECE with tumor size, histological type, differentiation, lymphoid metastasis, clinical stage, and prognosis were analyzed.RESULTS: The expressive rate of EMMPRIN and ECE was 66% and 45%, respectively.The expression of EMMPRIN and ECE was associated positively with lymphoid metastasis (both P<0.01, r=0.371 and 0.467, respectively), and inversely with survival time (P<0.01 and P<0.01).No relationship was found in the expression of EMMPRIN and ECE with tumor size, histological type, and differentiation (P>0.05).The expression of EMMPRIN was associated with the expression of HGF in NSCLC (P<0.05, r=0.243).CONCLUSION: The expression of EMMPRIN and ECE is associated with lymphoid metastasis and prognosis in NSCLC.Overexpression of EMMPRIN and ECE implies infavourable prognosis in NSCLC. 相似文献