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991.
AIM: To investigate the effect of intraventricular pressure change by volume overload (VOL) on expression of proto-oncogene c-fos,c-jun,c-myc and egr-1. METHODS: Left ventricular systolic pressure(LVSP) and left ventricular end diastolic pressure (LVEDP) of rat with VOL induced by aortacaval fistula operation and rats of control group were measured at 30 min, 1, 4, 6, 12 and 48 h after the operation,these mRNAs at the foregoing time points were measured by slot bloting method and quantified with densitometry. RESULTS: Be compared with the control group, VOL rats LVSP decreased (P<0.05) and declined most remarkably at 48 h,LVEDP elevated significantly at 30 min (P<0.05), reached a maximal value at 12 h and the levels of control group at 48 h (P>0.05) after the operation.The proto-oncogene expression signals were not detected in the control,negative controls and VOL rats at 30 min after the operation. The c-fos,c-jun and egr-1 mRNA signals appeared earlier,at 1 h, and c-myc mRNA increased later at 4 h.All reached peak value at 4 h and then declined gradually.The c-fos mRNA were not detected at 48 h. The c-myc,c-0jun and egr-1 mRNA persisted throught the entire observation period from 1 h to 48 h. CONCLUSIONS: During VOL early phase the overload have effect on expression of the proto-oncogene mRNA,c-fos,c-jun and egr-1 mRNA appear earlier, c-myc later,egr-1,c-jun and c-myc persist longer period, but the expressions do not strengthen with the ventricule wall load increase.This sequential induction pattern may reflect the time course regularity of the proto-oncogenes expression induced by VOL,and indicate the proto-oncogenes expression initiate while the heart load accumulate some extent and duration and the load magnitude may not play a critical role. 相似文献
992.
AIM: To study the relationship between the disturbance of nitric oxide/endothelin-1(NO/ET-1) and hepatic ischemia/reperfusion(I/R) injury as well as the regulation of NO/ET-1 system by hepatic ischemic preconditioning(IPC). METHODS: The changes of NO/ET-1 system and their relationship with hepatic I/R injury were compared between I/R group and IPC+I/R group in a rat hepatic I/R model. Two hours after reperfusion, the liver tissues were detected by RT-PCR to see whether there was inducible nitric oxide synthase (iNOS) mRNA expression. RESULTS:In the acute phase of hepatic reperfusion, the ratio of NO/ET-1 was reduced, which was due to a significant reduction of NO2-/NO3- (the metabolic product of NO) and significant elevation of ET-1 in the blood plasma. The content of ALT, AST, LDH and TNF-α in blood plasma, and of MDA in liver tissue were increased but ATP in liver tissue was reduced, the hepatic damage was deteriorated. The protection of the hepatic IPC was concerned with the elevation of the ratio of NO/ET-1 caused by the elevation of NO2-/NO3-, and reduction of ET-1 as well. There was no iNOS mRNA detected in the liver tissues.CONCLUSION: Hepatic I/R injury is related to the disturbance of NO/ET-1. The protection of the hepatic IPC in the acute phase might be conducted by its regulation of NO/ET-1 system. The cNOS rather than the iNOS generated the NO in this situation. 相似文献
993.
AIM:To investigate the effect of berberine on IL-1 or tumour necrosis factor (TNF) induced polymorphonuclear leucocyte(PMN)-endothelium adhesion and adhesion molecules.METHODS:Based on the model of human umbilical vein endothelial cell (HUVEC), this study adopted Rose Bengal Stain, cell ELISA, immunocyto-chemical techniques to investigate the effect of berberine on PMN-endothelium adhesion and the expression of cell adhesion molecules (CAMs).RESULTS:Berberine inhibited IL-1, TNF-induced HUVEC adhesion for PMN when pretreated HUVEC and antagonised IL-1, TNF-induced upregulation of ICAM-1 on HUVEC. Meanwhile, TNF-stimulated PMN adhesion for HUVEC and CD18 upexpression on PMN was diminished in the presence of berberine.CONCLUSION: Inhibite PMN-endothelium adhesion by downregulating the CAMs expression to inhibite PMN migration across endothelium is one of the mechanisms of antiinflammation of berberine. 相似文献
994.
AIM:To explore the relationship between change of serum melatonin (MT) and pathogenesis of hepatic encephalopathy (HE). METHODS: Changes of MT level in sera of cirrhosic patients with HE and without HE were determined by ELISA, normal serum served as control. The change of serum MT level in exacerbation and remission in HE was also determined.RESULTS:MT level in patients with HE was higher than that withour HE (P<0.01). MT levels of both groups were higher than that of normal group (P<0.01). They were (308.53±59.07) ng/L, (139.85±34.59)ng/L,(77.73±28.41)ng/L, respectively. Serum MT level in exacerbation was higher than that in remission (P<0.01), they were (301.52±66.42)ng/L and (147.81±23.31) ng/L, respectively. CONCLUSION: The elevation of MT content in sera may be closely related to the onset of hepatic coma. 相似文献
995.
996.
JIN Li-qin LU Jian-xin YU Kang YUAN Qian XIE Ke-jian WANG Kai-fa ZHANG Yu-lan 《园艺学报》2000,16(8):726-729
AIM: To study the activation effects of maize pollen polysaccharides(PPM) on human thoracic cavity macrophage (hTMΦ). METHODS: Activities of lactate dehydrogenase(LDH) and acid phosphatase (ACP) in the hTMΦ were detected by automatic biochemical analyzer, and the level of tumor necrosis factor alpha(TNF-α) and interleukin-6(IL-6) in the hTMΦ was analyzed by radioimmunoassay, after hTMΦ were cultured with 0.312, 0.625, 1.250, 2.500, 5.000 mg/mL PPM-RPMI 1640 for 24 and 48 hours in vitro. RESULTS: The activities of LDH and ACP increased in the hTMΦ induced by PPM, and the levels of TNF-α and IL-6 in the hTMΦ induced by PPM increased markedly too. And the induced expression effect of TNF-α and IL-6 is associated with the concentration of PPM, and time for PPM inducing. CONCLUSION: PPM can induce cytokines secretion in hTMΦ, and activate hTMΦ in vitro. 相似文献
997.
Neurovascular unit (NVU) is composed of neurons, endothelial cells, pericytes, astrocytes, macrophages/microglia, smooth muscle cells, extracellular matrix, etc, and plays vital roles in maintenance of the normal brain tissue function and cellular homeostasis. Cerebral ischemia caused by stroke can harm various components of NVU. Repairing damaged NVU and maintaining its structural and functional integrity are an effective way to improve stroke treatment. Resent research has found that rapamycin not only enhances autophagy of neurons but also effectively repairs the injuried components of NVU , thereby reducing neural damage after stroke. In this paper, the mechanisms of rapamycin underlying the repair of injured NVU after ischemic stroke is reviewed to provide guidance for its application in the treatment of stroke. 相似文献
998.
999.
不结球白菜维生素C和可溶性糖含量的遗传分析 总被引:14,自引:1,他引:13
采用主基因—多基因混合遗传模型分析方法,对不结球白菜乌塌菜×矮脚黄、雪克青×矮脚黄两个组合的维生素C、可溶性糖含量进行单世代和联合世代遗传分析。结果表明,两组合中维生素C含量遗传符合一个主基因和多基因的混合遗传模型,主基因遗传率为5268%~7412%。可溶性糖在雪克青×矮脚黄组合中也符合主基因—多基因遗传模型,主基因遗传率为8973%~8979%。维生素C和可溶性糖主基因效应均以加性效应为主,在乌塌菜×矮脚黄组合中,两性状主基因有较明显的负向显性效应,在雪克青×矮脚黄组合中,显性效应不明显。育种实践中应注重对主基因加性效应的利用。 相似文献
1000.