ABSTRACT
OBJECTIVE To investigate the risk factors and to take some useful measures to prevent and reduce infection in order to enhance medical quality,to ensure medical security,to strengthen hospital infection manangement and to prevent hospital infection effectively. METHODS We investigated the prevalence rate of hospital infection among our hospitalized patients in 2001,2003 and 2005, respectively. RESULTS The hospital infection rate was 4.6-6.42% in these years.Risk factors and the abuse of antibiotic were decreasing. CONCLUSIONS In order to control hospital infection rate,mensures should be taken including intensively monitoring the departments with high infection rate,strengthening hospital operation,rationally using the antibiotics,and studying the management for hospital infection.
ABSTRACT
The effects of drugs on intracellular calcium concentration(［Ca2+］i) were investigated with fura-2 fluorescence technique to investigate ATP and thrombin-induced Ca2+ entry in bovine aortic endothelial cells(BAEC). It was found that application of ATP and thrombin gave rise to biphasic ［Ca2+］i elevation. ATP or thrombin only triggered a fraction of cyclopiazonic acid(CPA)-sensitive Ca2+ store, which was enough to activate Ca2+ entry. The Ca2+ release induced by thrombin resulted from the activation of phospholipase C(PLC), whereas the PLC-independent mechanism was involved in ATP-induced Ca2+ release. Nifedipine had no effect on ATP and thrombin- induced Ca2+ entry. SK&F 96365 and ginsenoside-2A inhibited both ATP and CPA-induced Ca2+ entry, however no effect of them on thrombin-induced Ca2+ entry was found. The inhibitory effects of SK&F 96365 and ginsenoside-2A on CPA-induced Ca2+ entry were less than that on ATP-induced Ca2+ entry. The Ca2+ influx sensitive to SK&F 96365 was not the same as that to ginsenoside-2A. These observations suggest that both ATP and thrombin evoke Ca2+ release and Ca2+ influx by activation of different receptor. However their mechanisms appear different.
ABSTRACT
Endothelium-derived hyperpolarizing factor (EDHF) is the third factor released by en-dothelial cell other than NO and PGI2. It relaxes smooth muscle accompanied by a hyperpolarization in the membrane potential. EDHF may be epoxye-icosatrienoic acids (EETs) formed from arachidon-ic acid by the action of cytochrome P450. It is synthesized and/or released by endothelial cell as a result of an cytosolic Ca2+ increase, which is stimulated by the action of acetylcholine or bradykinin on endothelial cell. EDHF is shown to activate Ca2+-activated K+ channels and induce a hyperpolarization in the membrane potential in vascular smooth muscle. The hyperpolarization of the membrane inhibits the opening of voltage-dependentcalcium channels, allows calcium sequestration and removal mechanisms to lower intracellular calcium, and leads smooth muscle to relaxation. In large conducing arteries, EDHF may provide a secondary system to NO, which assumes primary importance in endothelium-dependent relaxation and inhibits the release of EDHF. However, in small resistance arteries, EDHF appears to be a major determinant of vascular calibre, and may be of primary importance in the regulation of vascular resistance.