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1.
抗生素的定义,首先来自于20世纪40年代链霉素的发现。在随后的几十年中,其他氨基糖苷类抗生素家族被大量发现并广泛应用,一度成为抗革兰阴性菌感染的首选抗生素。但由于其毒副作用较大,并且细菌对其不断产生耐药性,加上其他结构类别的新型抗生素的不断发现,使其一度几乎退出历史舞台。然而随着多重耐药细菌引起的感染率急剧上升,人们开始关注氨基糖苷类抗生素作为几种重要的治疗革兰阴性病原体的方案之一,并且发掘了其在治疗感染性疾病、艾滋病和遗传性疾病的潜力,使这个“老牌”抗生素重焕生机。  相似文献   
2.
Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c…  相似文献   
3.
患者,王丽莹,女,47岁,患者主诉,左侧乳房始终有一溃疡,并流脓汁,看过好多地方,用过好多抗菌素,始终未治愈。  相似文献   
4.
革兰阴性病原菌耐药性变化的分析   总被引:1,自引:0,他引:1  
目的:了解革兰阴性病原菌耐药水平的变化趋势。方法:对我院1998~2004年从各类临床标本分离出的革兰阴性病原菌的药敏试验结果进行统计分析。结果:病原菌对亚胺培南的总体敏感率始终保持在较高水平,以下依次为头孢他啶(69%)、阿米卡星(66%)和环丙沙星(66%),但是铜绿假单胞菌和不动杆菌对常用抗生素的敏感率呈下降趋势。大肠杆菌、肺炎克雷伯菌和阴沟肠杆菌对亚胺培南的敏感率始终维持很高水平,但对其它各类药物的敏感率大多呈现明显的下降趋势,或维持在较低水平。结论:革兰阴性病原菌耐药水平有增高的趋势。亚胺培南可作为重症患者经验用药的首选药物之一,慎重使用第3代头孢菌素,并尽量避免经验用药。  相似文献   
5.
目的:为寻求肠道G杆菌及弧菌快速鉴定的方法。方法:菌种经增菌及分离培养后,取菌落接种于综合生化培养基,并在综合生化培养基管口悬挂硫化氢和靛基质试纸条。同时以克氏双糖铁培养基作对照,置37℃培养18-24h。取综合生化管培养基,外加测试氧化酶,共获取11项生化指标。结果:对689株不同菌种与综合生化管培养基和常规双糖铁培养的测试结果,符合率为99.97%,(7577/7579)和99.79%(7563/7579)。结论:综合生化管是适合医疗卫生单位微生物实验室的一种快速检验方法。  相似文献   
6.
Bovine serum albumin was complexed with the core antigens of either Escherichia coli J5 LPS, Salmonella minnesota R595 LPS or E. coli lipid A. These core-BSA complexes were used for solid-phase coating in ELISAs for anti-core antibodies. Antibodies, binding to various parts of the core region were easily quantified in a single experimental set-up, which was hitherto not possible. The ELISA has only 3 incubation steps and is not costly as only moderate amounts of the core antigens (i.e., 1 microgram per test) were needed for coating. The sensitivity proved to be excellent and the complexes were biologically fully active (compared to native, smooth LPS), which make them suitable for the screening (after fusion) of monoclonal anti-core antibodies. Another possible application is the large-scale screening of blood-bank sera in order to find samples with a high anti-core antibody content.  相似文献   
7.
Chemokines are a superfamily of small chemotactic proteins. While increased levels of interleukin-8 have been measured in serum and urine during urinary tract infection, little is known about other chemokines in this condition. Monocyte chemoattractant protein (MCP)–1, macrophage inflammatory protein (MIP)–1, MIP-1 and interferon- inducible protein (IP)–10 were measured in 30 patients with culture-proven urosepsis during a 3-day follow-up and in 11 healthy humans after intravenous injection of endotoxin (4 ng/kg). Urine and serum levels of MCP-1, MIP-1, and IP-10, but not of MIP-1, were elevated in patients on admission, and decreased after initiation of antibiotic treatment. Endotoxin administration to healthy subjects induced increases in plasma and urine concentrations of all four chemokines. These data indicate that clinical and experimental gram-negative infection in humans is associated with enhanced production of chemokines that act mainly on mononuclear cells and that these chemokines are at least in part locally produced.  相似文献   
8.
Summary Acute leukaemia was complicated by pneumonia in 38 (34.8%) of 109 patients treated between 1979 and 1983; in 39.5% of the patients pneumonia occurred more than once. In 23 patients (60.5%) pneumonia occurred during cytostatic therapy, and 25 patients (65.8%) had less than 1000 mm2 granulocytes. Antibiotic therapy had no or only little effect in 70%. A total of 21 patients (55.3%) died of pneumonia. In 15 patients a direct relationship could be seen between pneumonia and the bacterial spectrum in the sputum. A prevalence of gram-negative bacteria was found (24 of 40 bacteria isolated, especially Enterobacteriaceae (19). Fungi were cultivated in 10 cases. Each of the typical pneumonia bacteria was only seen once respectively. It is most important that therapy begin immediately, even before the bacteria have been identified. Only then is there hope that the survival time of patients with acute leukaemia can be influenced.
  相似文献   
9.
目的 探讨耐碳青霉烯类革兰阴性杆菌的临床耐药性及耐药基因blaKPC的分子特征。方法 分析2017年1月-2018年12月某院临床检出的耐碳青霉烯类革兰阴性杆菌。通过WHONET 5.6软件对药物敏感试验数据进行统计分析,采用PCR检测碳青霉烯耐药基因blaKPC、blaNDM、blaIMP、blaVIM、blaOXA-48,对PCR阳性产物进行DNA测序,分析耐药基因的分子结构特点。结果 共收集510株耐碳青霉烯类革兰阴性杆菌,其中耐碳青霉烯类肠杆菌科细菌(CRE)420株,耐碳青霉烯非肠杆菌科细菌90株。菌株主要来自重症监护病房(ICU)、神经外科和呼吸科,分别占60.8%、11.8%、5.3%;标本来自痰、脓性分泌物、静脉血、无菌中段尿,分别占66.9%、8.8%、8.2%、6.5%。耐碳青霉烯类革兰阴性杆菌对常用抗菌药物具有较高的耐药性。PCR结果显示,420株CRE中blaKPC、blaNDM、blaIMP的阳性率分别为54.3%(228/420)、1.2%(5/420)、1.4%(6/420),未检测出blaVIM和blaOXA-48基因,其中肺炎克雷伯菌、产气肠杆菌、大肠埃希菌分别占携带blaKPC CRE的83.8%、11.8%、2.6%;其他少见菌种中也检出blaKPC基因。非肠杆菌科细菌中仅有2株鲍曼不动杆菌检测出blaKPC。DNA测序结果显示,174株携带blaKPC的菌株中173株检测为blaKPC-2、1株检测为blaKPC-1。结论 该地区耐碳青霉烯类革兰阴性菌以CRE为主,其中以携带blaKPC-2的肺炎克雷伯菌占绝对优势,其他菌株中也均有发现。提示临床需重点加强耐碳青霉烯类肺炎克雷伯菌的监测及预防,防控blaKPC的传播流行。  相似文献   
10.
The dissemination of carbapenem-resistant Gram-negative bacilli (CRGNB) is a global public health issue. CRGNB isolates are usually extensively drug-resistant or pandrug-resistant, resulting in limited antimicrobial treatment options and high mortality. A multidisciplinary guideline development group covering clinical infectious diseases, clinical microbiology, clinical pharmacology, infection control, and guideline methodology experts jointly developed the present clinical practice guidelines based on best available scientific evidence to address the clinical issues regarding laboratory testing, antimicrobial therapy, and prevention of CRGNB infections. This guideline focuses on carbapenem-resistant Enterobacteriales (CRE), carbapenem-resistant Acinetobacter baumannii (CRAB), and carbapenem-resistant Pseudomonas aeruginosa (CRPA). Sixteen clinical questions were proposed from the perspective of current clinical practice and translated into research questions using PICO (population, intervention, comparator, and outcomes) format to collect and synthesize relevant evidence to inform corresponding recommendations. The grading of recommendations, assessment, development and evaluation (GRADE) approach was used to evaluate the quality of evidence, benefit and risk profile of corresponding interventions and formulate recommendations or suggestions. Evidence extracted from systematic reviews and randomized controlled trials (RCTs) was considered preferentially for treatment-related clinical questions. Observational studies, non-controlled studies, and expert opinions were considered as supplementary evidence in the absence of RCTs. The strength of recommendations was classified as strong or conditional (weak). The evidence informing recommendations derives from studies worldwide, while the implementation suggestions combined the Chinese experience. The target audience of this guideline is clinician and related professionals involved in management of infectious diseases.  相似文献   
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