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AIM:To explore the effects of PMA(phorbol-12-myristate-13-acetate, a tumor promoter, mimicking the action of diacylglycerol on PKC)and laminin on the adhesion and the proliferation of human hepatocellular carcinoma cells, and provide a new clue to liver cancer treatment.METHODS:Human hepatocellular carcinoma cell line(BEL-7402)was used to identify the endogenous laminin and protein kinase C-α(PKC-α) expression, and the effects of laminin and PMA on the adhesion and the proliferation were also investigatedin vitro.RESULTS:By the effect of exogenous laminin, human hepatocellular carcinoma cell (BEL-7402) possessed endogenous laminin expression and increased the adhesion and the proliferation, which was showed the synergistic action by the effect of PMA in combination. By the action of PMA alone, the proliferation and the PKC-α expression increased by exogenous laminin were decreased, and the adhesion and the endogenous laminin expression were increased.CONCLUSIONS:The finding suggested that the adhesion and the proliferation of human hepatocellular carcinoma cell were closely related to the effects of endogenous or exogenous laminin, which were associated with cPKC-α activity. Therefore, the application of anti-laminin antibody in combination with PKC antagonist might be a new clue to find out the therapy for liver cancer. 相似文献
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AIM:To examine the effect of external counterpulsation(ECP) on renin-angiotensin system(RAS) and hemodynamics in dogs with myocardial ischemia and their relationship. METHODS:Acute myocardial ischemia was induced by occluding the left anterior descending of the dogs. The local renin activity, angiotensin Ⅱ(AngⅡ) level, angiotension-converting enzyme(ACE) activity were tested by biochemical methods and hemodynamics was recorded by a 8-channel physiological recorder.RESULTS:Ischemia could actiivate renin,ACE and AngⅡ in cardiovasculature and ECP reduced them except for renin in ischemic myocardium. Ischemia also could activate RAS in lung and kidney, which play an important role on circulating RAS, and ECP reduced them. Furthermore, ECP could improve hemodynamics and there existed a close relationship between local AngⅡlevel and hemodynamics. CONCLUSION:ECP can reduce local RAS and improve hemodynamics in dogs with myocardial ischemia, which might be one of mechanisms underlying the protective effect of ECP on ischemic myocardium. 相似文献
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AIM:To investigate the effect of Se-containing spirulina phycocyanin (Se-SPC) on liver injury of mice induced by carbon tetrachloride (CCl4). METHODS:The mouse model was conducted by intragastric feeding with 2% CCl4 oil for three times, meanwhile Se-SPC, spirulina phycocyanin (SPC) and Na2SeO3 were injected (ip) to various groups for 7 days. Then selenium (Se), glutathione peroxidase (GPx), superoxide dismutase (SOD), alanine aminotransferase (ALT), malondiaoldehyde (MDA) and nitric oxide (NO) levels in blood and liver were measured. RESULTS:The level of Se,GPx and SOD activities were obviously higher(P<0.05)but ALT activity,MDA and NO2-/NO3- levels were remarkably lower(P<0.05)in Se-SPC treated groups than those in CCl4 groups,and effects of high dose Se-SPC on Se,GPx,MDA and NO2-/NO3- were even more significant(P<0.01).Under the same dose of Se or protein,effects of all selected targets in Se-SPC groups were more efficient than those in SPC groups and inorganic-Se groups.Furthermore,Se levels had a positive correlation with GPx activity(r=01705),which had negative correlation with levels of MDA,NO2-/NO3- and ALT(r=-0.629,r=-0.336,r=-0.457,respectively), and positive correlations between ALT activity and MDA or NO2-/NO3- level were found (r=0.519,r=0.641). CONCLUSION:These results indicated that Se-SPC may attenuate liver injury of mice induced by CCl4 through its anti-inflammatory action and enhancing selenoenzyme expression. 相似文献
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ZHENG Hui LI Hong-yi WANG Zi-neng ZHAO Ying-she YU Li HE Si-cun BAI Zhi-quan ZHOU Zuo-yan YAO Ping WANG Yue-chun 《园艺学报》2002,18(5):553-555
AIM: The purpose of the present study was to explore the relationship between interleukin-6 mRNA expression and endometriosis. METHODS: Using the rat model, IL-6 mRNA expression in the endometrium was examined by RT-PCR. RESULTS: The expression of IL-6 mRNA in control rats did not change at 2, 4, 6 and 8 weeks after sham operation (P>0.05), but in model rats it gradually increased at 2, 4, 6 and 8 weeks after endometriosis (P<0.01). The expression of IL-6 mRNA in uterine endometrium with endometriosis was lower than in endometriotic tissue, but higher than in endometrium from healthy controls. CONCLUSION: The IL-6 mRNA expression may contribute to the development of endometriosis . The increase in IL-6 mRNA expression may promote the implantation and growth of endometriotic tissue. 相似文献
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The abnormality of the central noradrenergic system in Alzheimer's disease has two cases: decrease or increase. The former is easy to be understood, because it is resulted from the outstanding forfeit of the noradrenergic neurons in the nucleus locus ceruleus (nLC); but the noradrenalin concentration does not change and enen increase, it seems to disagree with the loss of the noradrenergic neurons in the nLC. This article put emphasis on it, enumerated the related evidence and analyzed the possible causes. At present time, the drugs to increase noradrenalin is used mostly in clinic. This paper summarized it and put forth our own opinions. 相似文献
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