【摘要】 目的 探讨老老年患者留置尿管内壁细菌生物被膜形成情况及其对导管相关感染(CRI)的影响。〖HTH〗方法〖HTSS〗 分析2007年2月—2009年10月住院的175例留置尿管患者,均为男性,年龄75~96岁,平均86岁。不同留置时间(7~15 d 53例、16~30 d 49例、31~45 d 44例、gt;45 d 29例)的尿管,于拔出尿管后运用超声震荡使尿管内表面生物被膜完全脱落,梯度稀释后进行生物被膜活菌计数,细菌的培养分类及构成比分析；采用扫描电镜观察尿管内壁细菌生物被膜形成的情况；观察尿管留置时间与生物被膜CRI的关系。结果 随着尿管留置时间的延长,尿管内表面生物被膜活菌计数呈指数趋势增长,CRI发生率有升高趋势,各置管时段组间尿管内表面生物被膜活菌计数及CRI发生率比较差异均有统计学意义(Plt;0.05)。扫描电镜见生物被膜的形成随时间的延长而明显增多。结论 细菌生物被膜形成是老老年患者留置尿管相关性尿路感染的重要致病因素,尿管留置时间越长,尿管生物被膜感染的危险性及几率越高。更换尿管或缩短留置时间仍是防止尿管生物被膜感染的主要方法。
Objective To investigate the influence of hypoxic preconditioning on pulmonary structure of rats exposed to simulated high altitude hypoxia and to explore the role of hypoxia inducible factor-1α（HIF-1α）.Methods Fifty-six Wistar rats were randomly divided into 7 groups(n=8 in each group),ie,a normal control group(N group)，an acute hypoxic control group(H0 group)，an acute hypoxic group(H1 group)，a 3 000 m hypoxic preconditioning group(C3.0 group)，a 3 000 m hypoxic preconditioning + acute hypoxic group (C3.1 group)，a 5 000 m hypoxic preconditioning group(C5.0 group)，and a 5 000 m hypoxic preconditioning + acute hypoxic group(C5.1 group).After treated with hypoxic preconditioning，the animals were exposed to simulated altitude of 6 000 m for 24 hours.Then the protein and mRNA expression of HIF-1α in lung of N，H0，C3.0 and C5.0 groups were assessed by Western blot and RT-PCR，respectively.The lung structure in N，H1，C3.1 and C5.1 groups was observed by light microscope and electron microscope.Results Pulmonary interstitial edema was apparently observed in H1 group，while significantly relieved in two hypoxic preconditioning groups.HIF-1α protein was not detected in rat lungs by Western blot analysis.Compared to N group，the levels of HIF-1α mRNA significantly increased in C3.0 group and C5.0 group(both Plt;0.01).Conclusions Hypoxic preconditioning can relieve hypoxic pulmonary interstitial edema and increase HIF-1α mRNA expression in rat lungs.HIF-1 may be involved in the process of hypoxic preconditioning in rat lungs.