血液净化治疗的重症患者血流感染的发生率和其菌群分布以及耐药性分析

目的:探讨血液净化治疗的重症患者血流感染的发生率,同时了解其血流感染的病原学分布情况以及耐药性特点,为临床合理用药提供参考依据。方法:选取2014年8月-2016年7月本院内科ICU行血液净化治疗的患者218例,对明确新发血流感染患者的致感染因素进行分析,同时分析其病原菌分布情况及耐药性特点。结果:218例患者发生新发血流感染者35例,占比16.06%,第二观察年限内发生率较第一观察年限有明显下降(P<0.05)。第一年观察年限分离出的致病菌构成以真菌及G-杆菌为主,第二观察年限分离出的致病菌构成以G+球菌及真菌为主。第一观察年限耐药率为38.10%(8/21),第二观察年限耐药率为57.14%(8/14)。结论:血液净化治疗的重症患者血流感染的发生率较高,病情病原菌中真菌属、G-杆菌、G+球菌分别为34.3%、31.4%、34.3%,G-杆菌耐药情况较为严重,而耐甲氧西林葡萄球菌有增多趋势,抗菌药物选择应同时兼顾G-菌和G+菌。     

肇庆市某院血流感染病原菌临床分布及耐药性分析

目的:了解2016-2018年肇庆市某院血培养病原菌临床分布及耐药性,为该地区血流感染的诊断和治疗提供实验室依据。方法:选取2016年1月-2018年12月血培养分离的654株病原菌及检测资料,采用生物梅里埃BacT/Alert 3D全自动血培养仪进行血培养,采用BIOFOSUN细菌鉴定药敏系统对病原菌进行菌种鉴定与药敏试验;采用WHONET 5.6对结果进行分析。结果:共分离654株病原菌,革兰阳性菌中检出率排名前三依次是表皮葡萄球菌57株(32.8%)、金黄色葡萄球菌42株(24.1%)和腐生葡萄球菌、化脓性链球菌、溶血葡萄球菌均为10株(5.7%);革兰阴性菌中检出率排名前三依次是大肠埃希菌123株(25.6%)、肺炎克雷伯菌102株(21.3%)、弗氏柠檬酸杆菌72株(15.0%);革兰阳性菌阳性率前三位的科室是新生儿科67株(38.5%)、呼吸科15株(8.6%)、心内科12株(6.9%)和内分泌科12株(6.9%);革兰阴性菌阳性率前三位科室是呼吸科62株(12.9%)、泌尿外科45株(9.4%)、内分泌科45株(9.4%)和肿瘤一区45株(9.4%);耐甲氧西林金黄色葡萄球菌(MRSA)检出率为52.4%,未发现耐万古霉素株;产超广谱β-内酰胺酶(ESBLs)大肠埃希菌、肺炎克雷伯菌检出率分别是50.4%和33.3%。结论:该院引起血流感染病原菌中,革兰阳性菌以表皮葡萄球菌、金黄色葡萄球菌为主,革兰阴性菌以大肠埃希菌、肺炎克雷伯菌、弗氏柠檬酸杆菌较为多见,产ESBLs菌株较为普遍;定期对血培养病原菌进行临床分布及耐药性分析,对血流感染的治疗和诊断十分重要。     

恶性肿瘤合并血流感染的临床特点

目的:研究恶性肿瘤合并血流感染患者的临床特征,为临床治疗提供参考。方法:选取2013-2017年本院恶性肿瘤合并血流感染患者221例。分析患者临床资料、肿瘤类型、致病菌及其药敏结果、转归情况。结果:本组男151例、女70例,死亡36例(16.3%),60岁以上老年人、低蛋白血症、贫血、TNM中晚期(Ⅲ、Ⅳ期)者较多。221例患者中最常见消化道肿瘤,占65.2%。共培养出病原菌237株,革兰阴性菌149株(62.9%)、革兰阳性菌73株(30.8%)、真菌15株(6.3%)。革兰阴性菌中大肠埃希菌占比最高(25.7%),对哌拉西林、氨苄西林、氨苄西林/舒巴坦耐药率最高(100%);肺炎克雷伯菌占比10.1%,对氨苄西林、哌拉西林耐药率较高,分别为100%、95.8%;鲍曼不动杆菌占比7.2%,对氨曲南耐药率最高(52.9%)。革兰阳性菌以表皮葡萄球菌、金黄色葡萄球菌为主,分别占7.6%、6.3%,对青霉素G耐药率最高,分别为83.3%、86.7%。真菌中白色念珠菌占比最高(4.2%)。结论:在恶性肿瘤患者的治疗过程中,应减少有创操作,严格无菌操作,预防血流感染的发生;同时恶性肿瘤患者合并血流感染以革兰阴性菌为主,临床应合理规范使用抗生素以提高疗效。     

血流感染成年患者的致病菌与药物敏感性研究

目的:研究血流感染成年患者的致病菌以及药物敏感性情况,为临床治疗提供依据。方法:分析在2015年1月-2016年12月本院各科室送检的临床患者血培养标本3 140例,阳性菌株359例,采用美国BD Phoenix~(TM)-100全自动鉴定药敏系统进行药物敏感性检测。结果:3 140例患者的血液标本中分离出病原菌359株,检出阳性率为11.43%。革兰阴性杆菌264株,占比73.54%;革兰阳性球菌91株,占比25.35%;真菌4例,占比1.11%。大肠埃希菌、阴沟肠杆菌对碳青霉烯类药物的耐药率为0;肺炎克雷白菌对碳青霉烯类药物的耐药率为3.57%。在金黄色葡萄球菌中耐甲氧西林金黄色葡萄球菌(MRSA)的检出率为21.43%,凝固酶阴性葡萄球菌(CNS)中耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)的检出率为71.43%。结论:血液感染成年患者的致病菌主要为革兰阴性杆菌为主,其中以大肠埃希菌和阴沟肠杆菌为主,对哌拉西林/他唑巴坦、阿米卡星及头孢他啶的耐药率较低;耐甲氧西林葡萄球菌对大环内酯类、青霉素类、氨基糖苷类、红霉素、克林霉素、喹诺酮类、复方磺胺的耐药率均较高,应引起临床研究的关注和重视。     

新生儿导管相关性血流感染病原学分布及耐药性分析

目的探讨新生儿重症监护室(NICU)导管相关性血流感染(CRBSI)病原学分布及耐药情况。方法将入住南华大学附属郴州市第一人民医院NICU行中心静脉置管的患儿纳入研究对象,根据置管部位分PICC组(经外周中心静脉置管)和UVC组(脐静脉置管),对CRBSI的发生率、临床特点、病原菌及药敏情况等进行回顾性分析。结果 CRBSI发生率为6.1/1000导管日,其中PICC组为5.3/1000导管日,UVC组为11.8/1000导管日。检出病原菌35株(真菌22株、G-菌8株、G+菌5株),真菌以白色假丝酵母菌为主,共17株(48.57%),G-菌以肺炎克雷伯菌为主,共5株(14.29%),G+菌以表皮葡萄球菌为主,共3株(8.57%)。真菌对两性霉素、氟康唑等敏感性高;G-菌对碳青霉烯类、哌拉西林/他唑巴坦及喹诺酮类敏感性高,对氨苄西林及头孢菌素类普遍耐药;G+菌对万古霉素及喹诺酮类敏感,对青霉素G、苯唑西林和头孢菌素普遍耐药。结论本院NICU CRBSI病原菌以白色假丝酵母菌最常见,对氟康唑敏感性高;其次为肺炎克雷伯菌,其耐药现象严重。     

宫颈癌根治术后泌尿系统感染患者的病原菌分布及耐药性分析

目的:检测宫颈癌根治术后泌尿系统感染患者的病原菌及耐药性,为临床合理用药提供指导。方法:选取本院2013年1月-2017年6月收治的90例宫颈癌根治术后泌尿系统感染患者,取尿袋中的尿液进行细菌培养,分离并鉴定病原菌,统计病原菌的分布情况。将分离出的病原菌实施耐药性检测,统计耐药率。结果:本组受试者中共分离出144株致病菌,革兰阴性菌85株、革兰阳性菌49株和真菌10株。革兰阴性菌中大肠埃希菌31.25%、肺炎克雷伯菌14.58%、阴沟肠杆菌6.94%,革兰阳性菌粪肠球菌18.06%和表皮葡萄球菌9.72%,真菌中白色假丝酵母菌4.86%和光滑假丝酵母菌2.08%。大肠埃希菌对亚胺培南的耐药率为0,肺炎克雷伯菌对氨曲南、亚胺培南、美罗培南、头孢噻肟、头孢吡肟、头孢他啶的耐药率为0,阴沟肠杆菌对环丙沙星、亚胺培南、庆大霉素、妥布霉素、左氧氟沙星、头孢噻肟的耐药率为0。粪肠球菌对氨苄西林、万古霉素的耐药率为0,表皮葡萄球菌对氨苄西林、万古霉素、呋喃妥因、利奈唑胺和四环素的耐药率为0。结论:宫颈癌根治术后泌尿系统感染患者的革兰阴性菌的构成比较高,应根据细菌培养结果和耐药性检测结果合理应用抗生素。     

140例慢性骨髓炎患者病原菌分布及耐药性分析

目的分析慢性骨髓炎患者病原菌分布及耐药性,以指导临床用药。方法回顾性分析2013年1月至2015年12月兰州军区兰州总医院全军创伤骨科中心收治的140例慢性骨髓炎患者的临床资料,对感染组织行细菌培养及药敏试验。结果共培养出病原菌34种146株,其中革兰氏阳性菌12种73株(占50.00%),革兰氏阴性菌20种69株(占47.26%),分枝杆菌、真菌各1株(各占0.69%)。革兰氏阳性菌感染率最高的4种细菌分别是金黄色葡萄球菌(占39.72%)、表皮葡萄球菌(占15.07%)、耐甲氧西林金黄色葡萄球菌(占13.70%)、粪肠球菌(占10.96%),该组耐药率最低的是万古霉素;革兰氏阴性菌感染率最高的4种细菌分别是铜绿假单胞菌(占26.08%)、阴沟肠杆菌(占15.94%)、大肠埃希菌(占14.49%)、肺炎克雷伯菌(占7.24%),该组耐药率最低的是亚胺培南。结论金黄色葡萄球菌及铜绿假单胞菌仍是引起慢性骨髓炎最主要的病原菌,了解慢性骨髓炎病原菌的分布及耐药性对指导临床用药具有重要意义。     

婴幼儿呼吸道感染细菌分布及药敏结果分析

目的:探讨沈阳地区婴幼儿呼吸道感染常见致病菌分布及耐药状况,为临床及时诊治患儿提供依据。方法:采用生物梅里埃公司的细菌鉴定系统(API)对沈阳市婴幼儿医院收治的1397例呼吸道感染患儿的痰液及血液进行细菌鉴定及K-B法药敏。结果:1397例患者的痰液标本中共检测到582株致病菌,其中,G-杆菌453株(77.8%),G+球菌98株(16.8%),混合感染15株(2.6%),真菌感染13株(2.2%),其他菌3株。G-杆菌对头孢他啶、头孢曲松、氨苄西林、头孢唑啉等耐药率均较高,对舒普深耐药率最低,其次为亚胺培南、头孢吡肟、环丙沙星等;G+球菌对红霉素、青霉素耐药率较高,对左旋氧氟沙星耐药率最低;3种真菌对抗真菌药物普遍敏感。结论:本地区小儿患者呼吸道感染以G-杆菌为主要致病菌,真菌的感染率也呈上升趋势,抗感染治疗应根据病原学结果集药物敏感试验选用抗菌药物。     

降钙素原水平检测对鉴别重症监护病房血流感染患者菌种的作用

目的:探讨PCT水平对鉴别重症监护病房血流感染患者菌种的价值。方法:选择2011年3月-2014年1月本院ICU患者131例作为研究对象,按照其菌种将其分为G-组、G+组及真菌组,比较各组PCT水平差异,并根据其ROC曲线判断血清PCT的诊断性能。结果:三组血清PCT中位数水平差异具有统计学意义(P<0.05);血清PCT水平对G-菌与G+菌及真菌所致的血流感染鉴别诊断性能较高。结论:血清PCT水平对于鉴别G-菌与G+菌或真菌引起的血流感染有一定的临床鉴别价值,但是对于G+菌与真菌引起的感染鉴别意义尚不明确。     

非发酵菌血流感染88例治疗经验分析

目的:分析呼吸内科与内科重症监护室(MICU)非发酵菌(Non-fermentative bacteria)血流感染患者经验性使用碳青霉烯类药物和酶抑制剂合剂治疗的临床效果。方法:回顾性分析本院2014年10月-2016年10月呼吸内科与MICU非发酵菌血流感染患者88例的临床资料,按照治疗用药方案不同将其分为碳青霉烯组42例和酶抑制剂组46例。两组患者均给予常规治疗,酶抑制剂组加用头孢哌酮治疗,碳青霉烯组加用亚胺培南治疗。比较两组临床疗效、不良反应及治疗前后的降钙素原和肾功能(肌酐)。结果:酶抑制剂组治疗总有效率为82.61%,高于碳青霉烯组的61.90%(P<0.05);酶抑制剂组死亡率为6.52%,低于碳青霉烯组的23.81%(P<0.05)。治疗后两组降钙素原、肌酐水平均较治疗前降低(P<0.05),且酶抑制剂组降钙素原、肌酐水平均低于碳青霉烯组(P<0.05)。碳青霉烯组不良反应发生率为26.19%(11/42),高于酶抑制剂组的19.56%(9/46),但比较差异无统计学意义(P>0.05)。结论:酶抑制剂合剂可以作为碳青霉烯类药物的替代选择,在血流感染治疗过程中发挥重要作用。     

A relative-risk framework for evaluating transient pathogen intrusion in distribution systems

Hydraulic transients generate significant negative pressures in water systems that may cause intrusion of contaminated water from the environment into the pipe. This paper expands the consideration of transient intrusion events from their purely hydraulic aspects by developing a risk-based framework for comparing the relative risk-reduction achieved by alternative transient-intrusion mitigation strategies. Alternative strategies may be any combination of changes to system operation or surge controls that would reduce the potential for intrusion of contaminants from the soil-groundwater environment surrounding the pipe. A reference groundwater contamination is assumed, and intrusion volumes and time-varying pathogen concentrations are computed respectively using hydraulic transient and water quality models. Risk-based measures are proposed to provide quantitative assessments of the relative reduction in the risk of receptor infection achieved by alternative mitigation strategies.     

不同条件下桩侧阻力端阻力性状及侧阻力分布概化与应用

根据24组51根桩竖向静载试验的侧阻力端阻力测试结果分析表明,桩侧土层性质与分布、桩长径比、后注浆效应是影响侧阻性状与分布的主要因素。软土中的桩其侧阻发挥正常,分布模式不受长径比影响;碎石土、砂土侧阻在桩顶以下约5d深度范围呈现应变软化,随深度增加逐渐演变为应变硬化导致桩身下部侧阻发挥滞后或发挥值显著降低,侧阻分布模式异化;土愈硬、长径比愈大,侧阻分布模式异化愈明显;后注浆对侧阻的增强与分布模式的影响,碎石土、砂土远甚于其它类土。工作荷载下的侧阻分布模式可概化为正梯形、倒梯形、橄榄形、灯笼形、蒜头形、峰谷形六种模式。端阻比随侧阻增强,随长径比增大而降低,随荷载水平提高呈非线性增长,给出了工作荷载下端阻比经验参考值。将每种侧阻概化模式分解为桩长l、kl的矩形、三角形分布侧阻单元,据此可查表确定供沉降计算的Mindlin解附加应力系数。计算结果表明,除正梯形和蒜头形分布外,其附加应力积分值按Geddes正梯形分布假定计算附加应力比实测侧阻概化分布大15%~74%,侧阻分布重心愈高差异愈大。     

Differential patterns of antimicrobial resistance in population subsets of Escherichia coli isolated from waste- and surface waters

The species Escherichia coli comprises different subgroups with distinct phylogeny, physiology and ecology and, thus, presumably, with different roles in antimicrobial resistance dissemination. E. coli strains isolated from raw and treated municipal wastewater and from urban water streams were characterized in terms of phylogenetic groups, antimicrobial resistance patterns and the presence of class 1 and class 2 integrons. Our main objective was to investigate the contribution of the different phylo-groups in antimicrobial resistance dissemination in urban waters. Groups A and B1 were predominant in all types of water, evidencing, respectively, the lowest and the highest resistance prevalence. Municipal wastewater treatment was accompanied by significant increases of ciprofloxacin and streptomycin resistance (p < 0.01). Antimicrobial resistance prevalence differed significantly between the different phylo-groups and within the same group, mainly in group A. Such differences contributed to explain the higher ciprofloxacin and streptomycin resistance rates observed in treated effluent in comparison with the raw wastewater. We conclude that the dynamics of the bacterial populations has a major role on the dissemination of antimicrobial resistance in the environment.     

Moment resistance statistical distribution of beam-to-column composite joints

In seismic design of steel–concrete composite moment resisting frames, the randomness of beam-to-column joint rotational response can affect the location of dissipative zones. In fact, in case of full-strength joints, the dissipation of the earthquake input energy occurs at the beam ends; conversely, in case of partial-strength joints, the connection components of beam-to-column joints are involved. Within this framework, random material variability of joint components plays an important role, because it affects the joint flexural strength and, as a consequence, also the plastic rotation supply. Therefore, within the framework of a research program aimed at the evaluation of the seismic reliability of steel–concrete composite frames including random material variability, this paper focuses the attention on the analysis of the influence of random material variability on the rotational response of beam-to-column joints. In particular, the aim of the work is the evaluation, by means of Monte Carlo simulations, of the statistical distribution laws of the parameters describing, from the overall point of view, the rotational behaviour of beam-to-column joints. Such distribution laws represent important input data for a complete probabilistic seismic demand analysis of steel–concrete composite moment-resisting frames where the joint modelling is performed by using rotational spring elements whose parameters are selected as random values satisfying the distribution laws previously derived.     

粉喷桩复合地基摩阻力分布规律分析

粉喷桩加固软土地基效果较好,但目前关于粉喷桩复合地基的加固机理的认识尚不明确,摩阻力及端阻力的分布规律有待研究。利用有限单元法,考虑桩土摩擦,对粉喷桩加固软土地基的工程背景进行了深入的计算,首先从机理上分析了粉喷桩加固软土地基的作用,然后详细探讨了粉喷桩不同的几何参数对摩阻力及下卧层附加应力的影响,确定了经济桩长及最佳置换率的范围,可为粉喷桩的后续理论研究提供一定的参考价值。     

Spatial distribution of infection risk of SARS transmission in a hospital ward

The classical Wells–Riley model for predicting risk of airborne transmission of diseases assumes a uniform spatial distribution of the infected cases in an enclosed space. A new mathematical model is developed here for predicting the spatial distribution of infection risk of airborne transmitted diseases by integrating the Wells–Riley equation into computational fluid dynamics. We applied our new integrated model to analyze a large nosocomial SARS outbreak in Hong Kong during the 2003 SARS epidemics, which was studied in the literature with regard to the association between airflow and SARS infection.     

Isolation, molecular characterization and antimicrobial resistance patterns of Salmonella and Escherichia coli isolates from meat-based fast food in Lebanon

The aim of this study was to characterize at the molecular level the different stains of Salmonella spp. and Escherichia coli that were isolated from meat-based fast food in Lebanon. In addition, this study evaluated the resistance of those strains to different antimicrobials that are commonly used. The foods included were Lahm-bi-Ajeen (LBA, meat pies) and Shawarma (Lebanese meat sandwiches similar to Gyros and Donairs, containing meat, vegetables, and sesame seeds-oil-based sauce). Polymerase chain reaction (PCR) was used to characterize and identify the strains of both bacteria. Salmonella species characterization was performed using rfb genes cluster genetic marker, while that of E. coli strains were carried out based on stx1, stx2, eaeA, fliC, and ehlyA virulence markers. The characterized strains were then tested for their response to various antimicrobials. The results showed that the tested foods were contaminated with Salmonella paratyphi (serogroup A) and Shiga Toxin (Stx)-producing E. coli (STX-EC). The PCR showed that 75% of E. coli tested strains was positive in PCR performed with stx1 primers, one of which was eaeA positive. Two of the tested strains were positive using PCR with fliC primers. The resistances of the various strains were evaluated using the following antimicrobials: Oxacillin, Teicoplanin, Trimethoprim/sulfamethoxazole, Gentamicin, Clindamycin, Cefotaxime, Cefuroxime, Erythromycin, and Vancomycin. Bacteria were highly resistant to one or more of the tested antimicrobials. Approximately 69% of E. coli and 77.8% of Salmonella spp. exhibited resistance. Salmonella spp. were shown to be 100% resistant to four antimicrobials: Oxacillin, Teicoplanin, Clindamycin, Vancomycin, and Erythromycin, while E. coli was 100% resistant to Teicoplanin and Trimethoprim/sulfamethoxazole. The most interesting findings were the high susceptibility of the E. coli to Gentamicin (100%). Highest resistance in the case of Salmonella spp. was seen against Cefotaxime (74%). Those two antimicrobials are commonly used for the treatment of enteric infections caused by gram-negative bacteria. The results showed that meat-based fast foods in Lebanon could be a public health hazard, especially Shawarma, as they may act as a potential vehicle for many antimicrobial-resistant pathogenic organisms. Improper hygienic standards and indiscriminate use of antimicrobials are two of the main causes for the prevalence of these pathogenic resistance strains in Lebanon. These results will emphasize the need to implement protective measures and more emphasis will be placed on the application of hygienic practices to reduce the levels of food contamination.     

沉井基础下沉阻力分布特征研究

以海口某大桥主墩的沉井基础为研究对象,对沉井的下沉全过程进行了实时监测,根据大量现场实测资料,系统分析了沉井基础的下沉机理和下沉过程中的受力特性,得出了沉井下沉不同深度,经过不同土层时井壁侧摩阻力和刃脚端阻力的大小及分布规律,提出了下沉系数K和侧壁摩阻力值σf的计算方法和经验公式,以及土压力系数ki的取值范围。在此基础上建立了下沉阻力的计算模型,给出了最大侧壁摩阻力f0的计算公式和分布特征,所得出的结论可供同类工程借鉴与参考。     

护理干预在颅脑损伤所致精神障碍患者中应用的临床效果观察

目的:观察护理干预在颅脑损伤所致精神障碍患者中应用的临床效果,探讨提高颅脑损伤所致精神障碍患者护理水平的措施。方法:选取颅脑损伤所致精神障碍的患者64例,按随机数字表法均分为传统组(n=32例)和干预组(n=32例),传统组采取传统的护理措施,干预组在传统护理措施基础上给予护理干预措施,比较两组患者治疗后NOSIE-30评分、MMSE量表评分和MoCA量表评分。结果:治疗4周后,干预组的NOSIE-30评分优于传统组,差异有统计学意义(P<0.05);治疗第2、4周,干预组的MoCA评分和MMSE评分均优于传统组,差异均有统计学意义(P<0.05)。结论:在颅脑损伤所致精神障碍患者临床护理过程中应积极加行护理干预措施,可促进患者临床症状的改善,有利于患者早日康复。     

The effects of UV disinfection on distribution pipe biofilm growth and pathogen incidence within the greater Stockholm area, Sweden

An assessment of the effects of the transition from conventional chlorination to UV disinfection on potable water biofilm growth and pathogen incidence was made. Two hydraulic systems were tested, one a 1.0 km polyethylene pilot-scale system within the Lov? waterworks, Stockholm, Sweden, as well as H?sselby and Nockeby municipal distribution systems within the greater Stockholm area. Biofilms were propagated on coupons and the amount of biomass analysed by standard culture and molecular methods. There was no measurable difference in biofilm biomass or pathogen incidence in the transition from conventional chlorination to UV-treatment in any system examined. With the exception of aeromonads, frank (salmonellae, enterobacteria) and opportunistic (legionellae) pathogens as well as indicator bacteria (E. coli, coliforms, enterococci) could not be detected within biofilms in either the pilot-scale or large-scale municipal system. Free-living protozoa were detected almost ubiquitously in biofilm samples in either experimental system though their exact significance and impact remains unknown and warrants further investigation.