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51.
铜绿假单胞菌噬菌体PaP3生物学特性的研究 总被引:2,自引:0,他引:2
目的测定铜绿假单胞菌噬菌体PaP3的最佳感染复数、一步生长曲线和吸附K值及交叉吸附K值等基本生物学特性。方法按照感染复数(MOI)分别为0.0001、0.001、0.01、0.1、1和10加入噬菌体纯培养液和宿主菌,充分裂解细菌后,测定噬菌体滴度;以MOI=10的比例加入噬菌体及宿主菌,进行一步生长实验;纯化PaP3颗粒,免疫家兔,获得抗血清,通过中和反应实验测定PaP3和其抗血清之间的吸附反应常数K值。同时,利用抗血清交叉中和试验确定本室分离的三株噬菌体之间的血清学关系。结果当MOI=0.001时PaP3感染其宿主菌产生的子代噬菌体滴度最高;根据一步生长实验结果绘制一步生长曲线;通过血清交叉中和反应得出不同的吸附常数。结论PaP3最佳感染复数为0.001,感染宿主菌的潜伏期是20min,爆发期是60min,平均爆发量约为31,其抗血清反应的吸附常数K值为262。 相似文献
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影响颅脑外伤术后颅内感染的危险因素分析 总被引:6,自引:0,他引:6
目的探讨影响颅脑外伤开颅术后颅内感染的危险因素。方法采用回顾性研究比较分析了912例颅脑损伤术后出现颅内感染与未出现颅内感染组间的差异因素。结果非感染 770例,颅内感染142例(15.6%)。感染类型有无菌性脑膜炎、细菌性脑膜炎、脑室炎及脑室积脓、脑脓肿、硬膜下腔积脓、术区皮下或(和)骨瓣下化脓或合并骨髓炎、切口感染。细菌检出率占感染的27.5%。颅脑外伤术后感染与高温季节、高龄、重度以上损伤、短期内两次以上手术、连续两侧开颅术、长时间 (>5 h)手术、显微外科手术、颅底与后颅凹手术、脑室外引流、皮下或硬膜外积液以及急诊手术等因素相关(P<0.05)。结论对具有上述危险冈素的易感患者应给予更密切的关注和预防性的处理。 相似文献
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Pulmonary Lophomonas blattarum infection in patients with kidney allograft transplantation 总被引:3,自引:0,他引:3
Yong Wang Zheng Tang Shuming Ji Zhen Zhang Jinsong Chen Zhen Cheng Dongrui Cheng Zhihong Liu Leishi Li 《Transplant international》2006,19(12):1006-1013
The aim of the study was to analyse the clinical manifestation and management of pulmonary Lophomonas blattarum infection in four allograft transplantation recipients retrospectively. Four patients with pulmonary L. blattarum infection were diagnosed by using Fiberoptic bronchoscopy (FOB) and bronchoalveolar lavage (BAL) examination. Their clinical manifestation and management are summarized. Four cases of pulmonary L. blattarum were found during the period from the second month to the third month after transplantation. Concurring infection by other pathogens was found in three of them. Common initial symptoms included fever (>38 degrees C) without cough and breathlessness. Lower lobe shadowing could be found on chest X-ray. Body temperature decreased to the normal range in three patients and to 37.5 degrees C in the other one, after intravenous injection of metronidazole and tapering immunosuppressant. Radiological examination confirmed improved health condition of the patients afterwards. Two patients received repeated FOB and only dead L. blattarum was found. Pulmonary L. blattarum infection in allograft transplant recipients carry relatively obscure initial symptoms. Possible L. blattarum infection needs to be screened in post-transplantation pulmonary infection patients with similar symptoms, especially in those who respond poorly to anti-infection treatment. Microscopic examination of BAL fluid can help to identify pulmonary L. blattarum infection and metronidazole is an ideal treatment choice. 相似文献
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58.
颅内肿瘤切除术后颅内感染危险因素分析 总被引:1,自引:0,他引:1
目的 探讨颅内肿瘤切除术后颅内感染的危险因素和预防措施。方法 回顾性分析442例颅内肿瘤切除术患者的临床资料。结果 442例颅内肿瘤切除术患者发生颅内感染33例,感染率为7.47%。非脑膜瘤手术颅内感染率为10.04%,高于脑膜瘤术后颅内感染率3.83%(P〈0.05);手术时间≥4h者颅内感染率为9.87%,高于手术时间〈4h者颅内感染率4.78%(P〈0.05);有脑脊液漏者颅内感染率为15.00%,高于无脑脊液漏者颅内感染率6.28%(P〈0.05);引流管留置≥24h者颅内感染率为11.58%,高于未留置或留置〈24h者颅内感染率5.03%(P〈0.05)。结论 手术时间≥4h、引流管留置时间≥24h、存在脑脊液漏是颅内肿瘤切除术后发生颅内感染的危险因素。 相似文献
59.
Nozha Brahmi Youssef Blel Nadia Kouraichi Salma Lahdhiri Hafedh Thabet Abderrazek Hedhili Mouldi Amamou 《Journal of infection and chemotherapy》2006,12(4):190-194
The present study included three periods: (1) a 12-month prerestriction and control period in 2001; (2) a 12-month restriction
period with reduced ceftazidime prescribing in favor of piperacillin-tazobactam (2002); (3) and a 24 month postrestriction
period (2003–2004). Note that, for results, P represents the difference between 2002 and 2001; P′, the difference between 2003 and 2001; and P″, the difference between 2004 and 2001. No changes in hygiene practices were observed during these three periods. The purpose
of this study was to assess the effect of reducing ceftazidime use in an intensive care unit (ICU) upon Gram-negative bacterial
resistance, particularly as regards Pseudomonas aeruginosa. During the three periods of the study, patients were similar concerning age, Simplified Acute Physiology Score (SAPSII),
the site of nosocomial infection, and the requirements for mechanical ventilation (75% in 2001, 76% in 2002, 74% in 2003,
and 85% in 2004). The most commonly isolated pathogens were P. aeruginosa, Acinetobacter baumannii, and Enterobacteriaceae. The use of ceftazidime decreased significantly from 12.6% in 2001 to 9% in 2002, to 3% in 2003 (P′ = 0.0009), and 2.6% in 2004 (P″ = 0.0001) in favor of piperacillin-tazobactam (0% 2001 to 3.7% in 2003; P′ = 0.002; and 5% in 2004; P″ = 0.0001). Simultaneously, we observed a significant decrease in isolates of P. aeruginosa resistant to piperacillin-tazobactam (P = 0.03; P′ = 0.004; P″ = 0.009), and those resistant to imipenem in 2003 (P′ = 0.008). We also noted a significant decrease in A. baumannii isolates resistant to ceftazidime (P′ = 0.01; P″ = 0.0004) and those resistant to imipenem in both 2002 and 2004 (P = 0.03; P″ = 0.04), and a considerable decrease in isolates of Klebsiella pneumoniae producing expanded spectrum betalactamase (ESBL) in 2003 and 2004 (P′ = 0.04; P″ = 6.10−5). In contrast, we noted an increase in penicillinase-producing isolates of K. pneumoniae, from 6% in 2001 to 16% in 2002 (p = 0.01), 20% in 2003 (P′ = 0.001), and 32% in 2004 (P″ = 10−6). We concluded that restriction of ceftazidime use was demonstrated to be efficient in reducing antimicrobial resistance,
especially to K. pneumoniae ESBL. 相似文献
60.