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1.
目的研究肺炎克雷伯菌中质粒介导的喹诺酮类耐药基因的分布和特性。方法 PCR检测qnr、qepA、aac(6’)-Ib-cr基因,阳性产物进行DNA测序以确定其基因型,接合转移试验探讨质粒介导的喹诺酮类耐药基因的体外转移性,稀释法测定试验菌株的MIC,用切胶回收的方法初步定位耐药基因。结果我们在肺炎克雷伯菌KP3606株发现新的基因亚型qnrB31,GenBank登录号为HQ418999,肺炎克雷伯菌KP4047株发现新的基因亚型qnrB32,GenBank登录号为HQ704413;体外接合转移试验获得成功,各菌株和各接合子对喹诺酮类药物敏感试验有不同的结果,未检出qnrA、qnrS、qnrC、qnrD、qepA、aac(6’)-Ib-cr基因;经基因定位,qnrB31和qnrB32基因位于约23kb的质粒上。结论在喹诺酮类耐药的各种基因中,qnrB是最有可能发生变异的基因,应引起足够的重视。  相似文献   

2.
目的 了解耐药不动杆菌氟喹诺酮类耐药基因的存在状况.方法 GNS-448药敏卡及K-B法测定抗菌药物的敏感性,聚合酶链反应(PCR)检测靶位DNA回旋酶编码基因(gyrA)与拓扑异构酶Ⅳ编码基因(parC)之氟喹诺酮耐药决定区突变分析,以及可移动遗传元件可介导的喹诺酮类耐药基因[qnrA、qnrB、qnrS、qepA、aac(6’)-Ⅰb-cr].结果 20株不动杆菌对12种常用抗菌药物严重耐药,对左氧氟沙星耐药率85%,亚胺培南90%,美洛培南耐药率达到95%.19株耐药鲍曼不动杆菌均检出gyrA基因氟喹诺酮耐药决定区(QRDR)第83位密码子TCA→TTA有义突变(氨基酸序列Ser→ Leu);20株不动杆菌中,parC基因均检出存在QRDR区第80位密码子TCG→TTG有义突变(氨基酸序列Ser→Leu);没有检出耐药鲍曼不动杆菌可移动遗传元件可介导的氟喹诺酮类耐药基因qnrA、qnrB、qnrS、qepA、aac(6’)-Ⅰ b-or.结论 鲍曼不动杆菌氟喹诺酮类药物的耐药机制主要与gyrA和parC基因QRDR区突变相关.  相似文献   

3.
目的研究临床分离的阴沟肠杆菌的耐药性和其对喹诺酮类抗生素耐药的分子机制。方法采用VITEK2型全自动微生物检测系统鉴定临床分离的细菌,用K—B法测定阴沟肠杆菌对25种抗生素的敏感性,用聚合酶链反应检测耐环丙沙星的阴沟肠杆菌质粒介导的喹诺酮类耐药基因,包括qnrS、qnrA、qnrB、qepA和aac(6’)-Ib,并对阳性的aac(6’)-Ib结果进行测序分析。结果71株阴沟肠杆菌对环丙沙星和左氧氟沙星的耐药率分别为46.5%和40.8%,对第一、二、三代头孢菌素类药物的耐药率在50%以上,对青霉素类药物的耐药率在70%以上,对含β-内酰胺酶抑制剂复合物的耐药率在50%以上,对氨基糖苷类药物(庆大霉素、妥布霉素)的耐药率在46.5%以上,对碳青霉烯类药物的敏感性最好,对亚胺培南、美罗培南的耐药率为0。37株耐环丙沙星的阴沟肠杆菌中1株检出qnrA基因(2.7%),4株检出qnrS基因(10.8%),qnrB基因全阴性,qnr基因的总阳性率为13.5%。2株检出qepA基因(5.4%)。25株捡出aac(6’)-Ib基因(67.6%),经测序证实其中5株为aac(6’)-Ib—cr(13.5%)。1株菌同时携带qnrs和aac(6’)-Ib—cr基因。质粒介导的喹诺酮类耐药基因的总携带率为29.7%。结论临床分离的耐喹诺酮类药物的阴沟肠杆菌携带qnrA、qnrS、qepA和aac(6’)-Ib—cr基因,未检出qnrB。qnr、qepA和aac(6’)-Ib—cr基因引起质粒介导的阴沟肠杆菌对喹诺酮类抗生素的耐药。  相似文献   

4.
目的了解广州地区质粒介导喹诺酮类耐药(PMQR)基因在铜绿假单胞菌中的流行状况并分析其与耐药之间的关系。方法收集2005-2007年临床分离到的212株铜绿假单胞菌,采用K-B纸片扩散法进行药敏试验,通过PCR检测质粒介导喹诺酮类耐药基因qnrA、qnrB、qnrS、qnrC、qnrD、aac(6’)-Ib-cr和qepA,并对阳性扩增产物进行DNA测序分析。结果 212株铜绿假单胞菌对喹诺酮类药物环丙沙星和左氧氟沙星的耐药率分别为10.8%(23/212)和19.3%(41/212)。qnrB、qnrS和aac(6’)-Ib-cr的阳性率分别为0.9%(2/212)、0.5%(1/212)和0.9%(2/212),qnrA、qnrC、qnrD、qepA未检出。4株PMQR基因阳性菌株中,仅1株对左氧氟沙星表现为耐药,其余对环丙沙星和左氧氟沙星均表现为敏感。结论 2005-2007年间广州地区铜绿假单胞菌耐药现象严重,该地区铜绿假单胞菌中已携带有PMQR基因,且敏感菌株中也有该类基因存在。  相似文献   

5.
目的 了解质粒介导喹诺酮耐药qnr基因在临床分离的三种常见肠杆菌科细菌中的分布,研究qnr阳性株的质粒特性和流行播散情况.方法 VITEK-60全自动微生物分析仪检测大肠埃希菌、肺炎克雷伯菌和阴沟肠杆菌对临床常用抗菌药物的耐药性,琼脂稀释法检测环丙沙星、诺氟沙星和左氧氟沙星的最低抑菌浓度(MIC);PCR扩增质粒介导的喹诺酮类耐药基因 (qnrA、qnrB、qnrC、qnrD、qnrS),阳性产物进行DNA测序比对以确定基因型;.对qnr基因阳性菌株进行接合转移试验,探讨qnr基因的可转移性;脉冲场凝胶电泳技术(PFGE)分析同源性及流行播散情况.结果 301株大肠埃希菌中共检出qnr阳性菌株14株,其中2株同时携带两种基因,qnrA、qnrB、qnrS基因分别检出5、2、9株;145株肺炎克雷伯菌中共检出qnr阳性菌株17株,其中1株同时携带两种基因,qnrA、qnrB、qnrS基因分别检出1、11、6株;173株阴沟肠杆菌中共检出qnr阳性菌株57株,其中3株同时携带两种基因,qnrA、qnrB、qnrS基因分别检出14、36、10株;所有菌株中均未检出qnrC和qnrD基因;接合转移试验结果显示,14株qnr基因阳性的大肠埃希菌、17株qnr阳性肺炎克雷伯菌和57株qnr阳性阴沟肠杆菌中分别有4、3和26株体外接合成功,qnrB阳性阴沟肠杆菌中少数菌株存在同源性,大多呈散发流行趋势.结论 临床肠杆科细菌中存在qnr阳性菌株的流行,总体以qnrB为主;qnr基因在喹诺酮类耐药和敏感菌株中均存在,喹诺酮类药物敏感菌株中qnr基因的检出值得关注;qnr基因可通过其所在质粒进行水平转移;携带qnrB基因的阴沟肠杆菌大多无同源性,呈散发流行趋势.  相似文献   

6.
目的检测临床分离的多重耐药德尔卑沙门菌对抗菌药物的敏感性及其耐药机制。方法选取8株多重耐药的德尔卑沙门菌,用微量肉汤稀释法检测对12种抗菌药物的敏感性。质粒指纹图谱分析耐药质粒分布。聚合酶链反应(PCR)检测TEM、CTX-M型β内酰胺酶基因、I型整合子相关的整合酶intI基因和qacEΔ12sul1耐消毒剂和磺胺基因,染色体和质粒介导喹诺酮耐药基因gyrA,parC,qnrA/qnrB/qnrC/qnrS,aac(6')-Ⅰb-cr,oqxAB等12种耐药基因。结果8株多重耐药菌对氨苄西林、哌拉西林、头孢呋辛、头孢西丁、卡那霉素、庆大霉素、复方磺胺甲唑、四环素及氯霉素等9种抗菌药物全部耐药,2株对头孢曲松耐药。所有菌株对亚胺培南、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、头孢吡肟敏感。质粒电泳显示,8株菌均携带1~4种大小不等质粒,其中约182kb大小质粒可发现于3株菌中。所有8株菌都携带TEM编码基因,intI和qacEΔ12sul1、aac(6')-Ⅰb-cr基因。有2株菌携CTX-M-14型耐药基因。在喹诺酮耐药相关基因中,5株菌的GyrA发生了D87S的氨基酸突变,5株菌的ParC发生了T57S的氨基酸突变。5株菌携带oqxAB基因,4株菌携带qnrS基因。所有菌株都未携带qnrA/qnrB/qnrC耐药基因。结论多重耐药沙门菌同时存在多种耐药基因,耐药质粒与I型整合子系统共存是导致菌株同时对多种结构各异的抗菌药物耐药的原因。  相似文献   

7.
目的探索本地区医院大肠埃希氏菌喹诺酮耐药基因的分布及耐药机制。方法采用PCR扩增与测序、基因初步定位、质粒接合转移实验等方法确定喹诺酮耐药的大肠埃希氏菌qnr的基因类型,以分析研究有关的耐药特点与机制。结果各大肠埃希氏菌株中仅qnrB基因阳性,qnrA、qnrS、qnrC、qnrD、qepA、aac(6’)-Ib-cr基因均阴性;并且qnrB基因包括qnrB2、qnrB5、qnrB9、qnrB16、qnrB18、qnrB19和qnrB31等位基因;在这些qnrB等位基因中,qnrB31与qnrB16、qnrB2与qnrB9同源性较高;各qnrB等位基因分别位于约21.0 kb至28.0 kb长的质粒上。结论在本地区医院存在不同的qnrB等位基因流行;实验菌株的喹诺酮耐药与qnrB等位基因结构中LexA-蛋白结合位点共有序列缺失有关。  相似文献   

8.
何菡  孙桂珍  王清涛 《北京医学》2012,34(12):1055-1059
目的 了解质粒介导喹诺酮耐药基因qnr在肺炎克雷伯杆菌中的流行情况并探讨其相关耐药机制.方法 纸片法和E-test法检测肺炎克雷伯杆菌对抗菌药物的敏感性;多重PCR方法检测菌株中qnr的携带情况;接合实验证实qnr的可转移性;肠道细菌基因间重复序列PCR(ERIC-PCR)分型检测qnr阳性菌株的同源性;变性高效液相色谱技术(DHPLC)检测qnr阳性菌株染色体旋转酶GyrA和拓扑异构酶ParC变异位点.结果 2006年首都医科大学附属北京朝阳医院临床分离的160株肺炎克雷伯杆菌中检出48株qnr阳性菌株,分别为1株qnrA阳性菌,21株qnrB阳性菌,22株qnrS阳性菌,4株同时携带qnrB和qnrS.25株qnrB阳性菌和7株qnrS阳性菌接合实验成功.同源性分析未发现qnr基因在院内有暴发流行.检测到GyrA亚基存在4种氨基酸突变类型,ParC亚基存在2种氨基酸突变类型.结论 本研究分离的肺炎克雷伯杆菌中qnrB和qnrS为流行亚型.qnr基因在不同菌株中可水平转移,与编码GyrA和ParC氨基酸位点突变同时存在时可导致高水平耐药.  相似文献   

9.
目的了解产超广谱β-内酰胺酶(extended spectrum beta-lactamases,ESBLs)大肠埃希菌和肺炎克雷伯菌的遗传标记基因(整合子qacE△1、转座子tnpU)、氨基糖苷类修饰酶编码aac(6′)-Ib基因和喹诺酮类药物耐药qnrA基因分布状况,为临床使用药物治疗感染和消毒灭菌工作提供参考。方法收集本院的产ESBLs大肠埃希菌和肺炎克雷伯菌共60株,采用PCR方法检测这些菌株中qacE△1、tnpU、aac(6′)-Ib和qnrA基因,MIC法药物敏感试验分析菌株的耐药性。结果 60株产ESBLs的大肠埃希菌和肺炎克雷伯菌中qacEΔ1基因检出率61.7%,tnpU基因检出率7.6%,aac(6′)-Ib检出率为11.7%,qnrA基因检出率3.3%。60株菌中有38株含1种或以上基因,其药敏敏感度最高的是亚胺培南、厄它培南、哌拉西林/他唑巴坦,敏感率均为97.4%,而对氨苄西林和头孢唑啉完全耐药。结论产ESBLs大肠埃希菌和肺炎克雷伯菌的耐药与耐药基因传递机制整合子和转座子系统密切相关,分离株携带qacE△1、tnpU、aac(6′)-Ib和qnrA基因是细菌呈多重耐药的主要原因,提示临床应慎重用药。  相似文献   

10.
目的 了解阴沟肠杆菌中质粒介导喹诺酮类耐药基因qnrA、qnrB、qnrS的流行现状及耐药性检测.方法 PCR法对57株环丙沙星耐药的阴沟肠杆菌进行qnrA、qnrB、qnrS基因检测,并用琼脂稀释法对11种抗菌药物的耐药性测定.结果 57株阴沟肠杆菌中阴沟肠杆菌对5种喹诺酮类药物的耐药率高达89.5% ~ 100%,对氨苄西林、四环素、头孢曲松、头孢美唑、庆大霉素、亚胺培南的耐药率分别为100%、64.9%、87.7%、93%、49.1%和100%.qnrA基因阳性19株(33.3%),qnrB基因阳性15株(26.3%),qnrS基因阳性2株(3.5%),qnrA基因和qnrB基因同时阳性8株,qnrA基因和qnrS基因同时阳性1株,qnrB基因和qnrS基因同时阳性1株.结论 我院阴沟肠杆菌临床分离株中存在qnr基因的流行,qnr阳性菌株呈多重耐药,应加强对该类基因的监测及临床用药监管.  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

19.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

20.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

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