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21.
目的:观察儿科抗生素的应用状况以及葡萄糖球菌的耐药情况,并对儿科抗生素使用合理性进行评价。方法:选取我院儿科抗生素应用状况数据库资料作为研究对象,分析我院儿科抗生素应用状况、葡萄球菌对不同抗生素的耐药性情况。结果:儿科抗生素使用率较高,平均使用率达90.96%,而且某些单品种抗生素使用较多,微生物送检率达91.29%;葡萄球菌对常用抗生素青霉素、红霉素等的耐药性可达88.0%以上,对万古霉素尚未产生耐药性,辛内吉及呋喃坦啶耐药性较低,低于10%;抗生素二联用情况也比较常见,占35.83%,三联及以上联用情况尚未出现。结论:儿科抗生素使用率比较高,而且葡萄球菌的耐药性情况也较为普遍,临床医护人员需要对此引起重视,合理应用抗生素,保证疗效的同时,预防细菌耐药性的增强。  相似文献   
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临床上骨科内固定手术后,由于感染或者感染后形成的高抗药性生物膜,在全身应用大剂量抗生素的情况下,病灶局部组织仍难达到有效的抗生素浓度,使感染久治难愈,导致内固定失败,为了减少术后感染的发生,可以使用载抗生素内植入物来进行治疗,或者在感染后经过清创后再次使用载抗生素内植入物进行治疗.本文对载抗生素内植入物的研究进展作一综述.  相似文献   
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Rationale:Whereas metronidazole-induced hepatotoxicity is quite rare in the general population, in individuals carrying a nucleotide excision repair disorder, namely Cockayne syndrome, there is a high risk of developing this complication.Patient concerns:We report the case of a 44-year-old man, affected by xeroderma pigmentosum, who was admitted to the hospital presenting aspiration pneumoniae caused by worsening dysphagia and with severe hepatotoxicity during the hospitalization.Diagnoses:Acute hepatitis, which was leading to acute liver failure, occurred during antibiotic treatment with metronidazole and ceftazidime with an elevation of liver enzymes consistent with hepatocellular damage pattern.Interventions:Hydration with glucose 5% solution, pantoprazole and vitamin K were administered, meanwhile other causes of hepatitis were ruled out and the ongoing antibiotic treatment was stopped suspecting a drug-induced liver injury.Outcomes:Liver function nearly completely recovered 1 month later with a first rapid improvement, within few days, of aminotransferases and coagulation studies, and slower of cholestatic enzymes.Lessons:We describe the first case available in the literature of hepatotoxicity associated with metronidazole treatment in a xeroderma pigmentosum patient. Clinicians therefore, based on this report and according to the possible underlying mechanism shared by other genetic diseases characterized by alterations in the pathway of DNA-repair, should consider such adverse event also in patients affected by this rare disease.  相似文献   
24.
从一株吸水链霉菌的培养液中分离得到对难辨梭状芽孢杆菌有作用的抗生素T0007A。基于其理化及生物学性质、光谱特征和氨基酸分析结果,确认抗生素T0007A为由脯氨酸∶亮氨酸∶异亮氨酸(8∶7∶1)组成的新肽类抗生素。  相似文献   
25.
Current national and international trends in antibiotic resistance are becoming a public health crisis. Multi-drug resistant organisms are more prevalent in hospital settings and, alarmingly, are now being identified in the community. Over-reliance on broad-spectrum antibiotics, as well as inappropriate prescribing practices, play a significant role in encouraging the emergence of resistant organisms. This article reviews the mechanisms of bacterial resistance, current trends in national and international antibiotic resistance, and examines approaches to combat pathogens while sparing benign microbes.  相似文献   
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The progressive increase in antibiotic resistance in recent decades calls for urgent development of new antibiotics and antibiotic stewardship programs to help select appropriate treatments with the goal of minimising further emergence of resistance and to optimise clinical outcomes. Three new tetracycline-class antibiotics, eravacycline, omadacycline, and tigecycline, have been approved within the past 15 years, and represent a new era in the use of tetracyclines. These drugs overcome the two main mechanisms of acquired tetracycline-class resistance and exhibit a broad spectrum of in vitro activity against gram-positive, gram-negative, anaerobic, and atypical pathogens, including many drug-resistant strains. We provide an overview of the three generations of tetracycline-class drugs, focussing on the efficacy, safety, and clinical utility of these three new third-generation tetracycline-class drugs. We also consider various scenarios of unmet clinical needs where patients might benefit from re-engagement with tetracycline-class antibiotics including outpatient treatment options, patients with known β-lactam antibiotic allergy, reducing the risk of Clostridioides difficile infection, and their potential as monotherapy in polymicrobial infections while minimising the risk of any potential drug-drug interaction.

KEY MESSAGES

  • The long-standing safety profile and broad spectrum of activity of tetracycline-class antibiotics made them a popular choice for treatment of various bacterial infections; unfortunately, antimicrobial resistance has limited the utility of the early-generation tetracycline agents.
  • The latest generation of tetracycline-class antibiotics, including eravacycline, tigecycline, and omadacycline, overcomes the most common acquired tetracycline resistance mechanisms.
  • Based on in vitro characteristics and clinical data, these newer tetracycline agents provide an effective antibiotic option in the treatment of approved indications in patients with unmet clinical needs – including patients with severe penicillin allergy, with renal or hepatic insufficiency, recent Clostridioides difficile infection, or polymicrobial infections, and those at risk of drug–drug interactions.
  相似文献   
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Purpose:?An unbiased approach of drug discovery through high-throughput screening (HTS) of libraries of chemically defined and bioactive small molecule compounds was used to identify modulators of radiation injury with an emphasis on radioprotectors and mitigators rather than radiosensitisers. Assay system endpoints included radiation-induced genotoxicity and DNA damage in yeast and apoptosis in murine lymphocytes. Large-scale data mining of chemically diverse libraries identified agents that were effective with all endpoints. HTS of bioactive compound libraries against murine lymphocytes profiled tetracycline and fluoroquinolone antibiotics and cyclopiazonic acid as having activity, and structure-activity analysis showed a common pharmacophore. Purine nucleosides, the interferon inducer tilorone, and linoleic acid were also identified as potential mitigators of radiation damage that often were also radioprotective. Many of these compounds enhance DNA repair, have anti-inflammatory activity, and stimulate hematopoiesis. Selected compounds within these initial verified hits from both types of libraries identified potent mitigators of lethal whole body irradiation (WBI) in mice.

Conclusion:?In spite of the fact that in vitro HTS has limitations and is unable to fully recapitulate all aspects of the complex in vivo acute radiation response, it identified several classes of molecules that had activity as radioprotectors and radiomitigators of the hematopoietic system in vivo. In the future, addition of 3-dimensional (3-D) or stem cell cultures or pathway analysis, may improve the power of HTS, but our findings indicate that common, evolutionary conserved, canonical pathways can be identified that could be exploited to mitigate radiation-induced defects.  相似文献   
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