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61.
2003-2005年新生儿感染常见致病菌及耐药性的变迁   总被引:10,自引:2,他引:8  
目的了解本地区新生儿2003至2005年感染常见致病菌的种类及耐药的现状,以指导临床合理应用抗生素。方法收集我院新生儿科2003年1月至2005年12月收治的613份体液培养阳性(痰液、血液、分泌物、胃液等标本)的患儿资料,对常见检出菌及其耐药性的变迁情况进行分析。结果共检出40种613株病原菌,以革兰阴性杆菌为主约占57.6%,而肺炎克雷伯菌和大肠埃希菌分别位于前二位,其产ESBLs菌株检出率分别为78.1%和82.6%。药敏结果显示,常见致病菌对青霉素、第一、二代头胞类抗生素、红霉素类耐药性显著增加,但对第三代头胞类抗生素如头孢曲松、头孢噻肟(凯福隆)、头孢他啶(复达欣)及B内酰胺酶抑制剂复方制剂、碳青霉烯类、万古霉素等较敏感。产ESBLs菌仅对亚胺培南及B内酰胺酶抑制剂复方制剂敏感。结论革兰阴性杆菌特别是肺炎克雷伯菌和大肠埃希菌是新生儿感染主要病原菌,产ESBLs菌比例增加应引起高度重视。碳青霉烯类、哌拉西林/三唑巴坦和头孢哌酮/舒巴坦,可作为新生儿严重医院感染经验用药,应尽量根据药敏试验调整抗生素。  相似文献   
62.
目的 探讨多药耐药基因(mdrl)转染骨髓造血细胞移植后,其在体内分布和安全性.方法 骨髓造血细胞转染mdrl基因后移植入BALB/C鼠,免疫组织化学和RT.PCR观察mdrl基因在骨髓、外周血及重要脏器的表达;监测外周血白细胞变化及重要脏器病检分析其安全性.结果 P-糖蛋白(P-gP)在骨髓表达率随时间降低,各时间组差异无统计学意义(x2=3.74,P>0.05),在外周血表达第2月最高,为(9.95±1.84)%,各时间组差异无统计学意义(x2=2.31,P>0.05),在重要脏器无表达;移植未转染组与移植转染组外周血白细胞计数至移植60 d后,两者差异有统计学意义(t=6.173,P<0.05),病检除肝和肾有炎性渗出和水肿病变外,其余无异常.结论 mdrl基因在骨髓和外周血有持续较高表达,在重要脏器无表达;mdrl基因转染对造血恢复及重要脏器无明显影响.  相似文献   
63.
Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy.  相似文献   
64.
德国小蠊抗药性及其抗性衰退情况研究   总被引:4,自引:1,他引:3  
目的了解德国小蠊的抗药性及抗药性衰退情况.方法以点滴法测定德国小蠊对溴氰菊酯、敌敌畏、二氯苯醚菊酯、残杀威等的抗药性及抗药性衰退情况.结果现场品系分别为0.098、0.490、5.612、0.741ug/虫,正常饲养1年后抗性分别为0.086、0.232、3.412、0.317ug/虫,5年后抗性分别为0.008、0.123、0.410、0.0811ug/虫,LD50最高为二氯苯醚菊酯,1年后抗性衰退倍数范围为1.14~2.39,5年后抗性衰退倍数范围为3.98~13.69.结论具有高等抗性德国小蠊经实验室饲养5年后抗性基本衰退.  相似文献   
65.
目的探讨血清甘油三酯/高密度脂蛋白胆固醇(TG/HDL-C)比值水平与胰岛素抵抗的关系。方法对146例2型糖尿病患者测定空腹胰岛素(FINS)、空腹血糖(FBG),TG,HDL-C,低密度脂蛋白胆固醇(LDL-C)水平,计算TG/HDL-C比值,并按TG/HDL-C和FBG水平分组,比较组间差异与胰岛素抵抗指数(HOMA-IR)的关系。结果糖尿病组TG/HDL-C比值水平(2.531±3.741)显著高于正常对照组(0.898±0.487),差异有显著性(t=4.279,P<0.001)。TG/HDL-C比值增高组HOMA-IR(3.291±2.004)明显高于TG/HDL-C比值正常组(2.403±1.789),差异有显著性(t=2.796,P<0.01)。血糖水平>10 mmol/L组HOMA-IR(3.575±2.216)明显大于血糖水平≤10mmol/L组(2.384±1.584),差异有显著性(t=3.760,P<0.001)。结论糖尿病患者TG/HDL-C比值水平与胰岛素抵抗存在着密切的相关性。  相似文献   
66.
目的 评价耐药对地区肺结核病治疗效果的影响.方法 对上海地区2004年2月-9月新登记敏感及耐药肺结核病人1年治疗转归进行分析和比较.结果 在全市各区(县)结核病定点医院新登记1 597例肺结核病病人中,805例培养阳性,其中731例经菌型鉴定为结核分枝杆菌的病人纳入分析.731例病人的总耐药率为18.7%,耐多药率为6.7%.敏感组治疗成功率达到93.0%,非MDR的耐药病人治疗成功率达到85%以上,MDR组治疗成功率为71.4%.经x2检验,差别有统计学意义(x2=83.996 8,P<0.01).在68例治疗不成功的病人中,耐药病人占38.2%;而在30例治疗失败的病人中,耐药病人占60%.复治敏感病人的治疗成功率(92.0%)与初治敏感病人(93.1%)相当,但是复治耐药病人的治疗成功率远低于初治耐药病人.结论 (1)上海地区肺结核病病人治疗管理效果良好;(2)耐药是肺结核病治疗失败的重要因素,应加强和改进对耐药结核病的治疗措施;(3)耐药和敏感病人治疗效果存在较大差异,应分别评价.  相似文献   
67.
目的:评价乳胶结合实验,检测重症监护病房(ICU)耐甲氧西林金黄色葡萄球菌(MRSA)及其肠毒素(SE),并进行耐药性分析。方法:收集260株金黄色葡萄球菌临床分离株,通过药敏试验将其分为耐甲氧西林金黄色葡萄球菌和甲氧西林敏感金黄色葡萄球菌(MSSA),用反向间接血凝试验(RPHA)检测金黄色葡萄球菌肠毒素。结果:MRSA产肠毒素为134株,MSSA产肠毒素为38株,MRSA产肠毒素率为100%,MSSA产肠毒素率为30%。结论:重症监护病房应重视MRSA的检测和金黄色葡萄球菌肠毒素的检测,合理使用广谱抗菌药物。  相似文献   
68.
69.
BACKGROUND: Chronic kidney disease patients who are resistant to erythropoietin (EPO) treatment may suffer from malnutrition and/or inflammation. METHODS: In a cross-sectional study of haemodialysis patients, we investigated the relationship between the natural logarithm of the weekly EPO dose normalized for post-dialysis body weight and outcome measures of nutrition and/or inflammation [BMI, albumin and C reactive protein (CRP)] by means of multiple linear regression analysis. On the basis of the decile distribution of weekly EPO doses, we also evaluated four groups of patients: untreated, hyper-responders, normo-responders and hypo-responders. RESULTS: Six hundred and seventy-seven adult haemodialysis patients were recruited from five Italian centres. BMI and albumin were lower in the hypo-responders than in the other groups (21.3+/-3.8 vs 24.4+/-4.7 kg/m(2), P<0.001; and 3.8+/-0.6 vs 4.1+/-0.4 g/dl, P<0.001), whereas the median CRP level was higher (1.9 vs 0.8 mg/dl, P = 0.004). The median weekly EPO dose ranged from 30 IU/kg/week in the hyper-responsive group to 263 IU/kg/week in the hypo-responsive group. Transferrin saturation linearly decreased from the hyper- to hypo-responsive group (37+/-15 to 25+/-10%, P = 0.003), without any differences in transferrin levels. Ferritin levels were lower in the hypo-responsive than in the other patients (median 318 vs 445 ng/ml, P = 0.01). At multiple linear regression analysis, haemoglobin, BMI, albumin, CRP and serum iron levels were independently associated with the natural logarithm of the weekly EPO dose (R(2) = 0.22). CONCLUSIONS: Our findings support a clear association between EPO responsiveness and nutritional and inflammation variables in haemodialysis patients; iron deficiency is still a major cause of hypo-responsiveness.  相似文献   
70.
Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells.  相似文献   
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