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91.
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C. Duncan K. Savage M. Williams B. Dickerson A. V. Kondas K. A. Fitzpatrick J. L. Guerrero T. Spraker G. J. Kersh 《Transboundary and Emerging Diseases》2013,60(4):345-350
In 2010, Coxiella burnetii was identified at a high prevalence in the placentas of Northern fur seals (Callorhinus ursinus) collected at a single rookery on St. Paul Island Alaska; an area of the United States where the agent was not known to be present. As contamination was hypothesized as a potential cause of false positives, but nothing was known about environmental C. burnetii in the region, an environmental survey was conducted to look for the prevalence and distribution of the organism on the island. While environmental prevalence was low, two strains of the organism were identified using PCR targeting the COM1 and IS1111 genes. The two strains are consistent with the organism that has been increasingly identified in marine mammals as well as a strain type more commonly found in terrestrial environments and associated with disease in humans and terrestrial animals. Further work is needed to elucidate information regarding the ecology of this organism in this region, particularly in association with the coastal environment. 相似文献
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D.R. MacFadden B. Coburn N. Shah A. Robicsek R. Savage M. Elligsen N. Daneman 《Clinical microbiology and infection》2019,25(1):108.e1-108.e7
Objectives
Early empiric antibiotic therapy in patients can improve clinical outcomes in Gram-negative bacteraemia. However, the widespread prevalence of antibiotic-resistant pathogens compromises our ability to provide adequate therapy while minimizing use of broad antibiotics. We sought to determine whether readily available electronic medical record data could be used to develop predictive models for decision support in Gram-negative bacteraemia.Methods
We performed a multi-centre cohort study, in Canada and the USA, of hospitalized patients with Gram-negative bloodstream infection from April 2010 to March 2015. We analysed multivariable models for prediction of antibiotic susceptibility at two empiric windows: Gram-stain-guided and pathogen-guided treatment. Decision-support models for empiric antibiotic selection were developed based on three clinical decision thresholds of acceptable adequate coverage (80%, 90% and 95%).Results
A total of 1832 patients with Gram-negative bacteraemia were evaluated. Multivariable models showed good discrimination across countries and at both Gram-stain-guided (12 models, areas under the curve (AUCs) 0.68–0.89, optimism-corrected AUCs 0.63–0.85) and pathogen-guided (12 models, AUCs 0.75–0.98, optimism-corrected AUCs 0.64–0.95) windows. Compared to antibiogram-guided therapy, decision-support models of antibiotic selection incorporating individual patient characteristics and prior culture results have the potential to increase use of narrower-spectrum antibiotics (in up to 78% of patients) while reducing inadequate therapy.Conclusions
Multivariable models using readily available epidemiologic factors can be used to predict antimicrobial susceptibility in infecting pathogens with reasonable discriminatory ability. Implementation of sequential predictive models for real-time individualized empiric antibiotic decision-making has the potential to both optimize adequate coverage for patients while minimizing overuse of broad-spectrum antibiotics, and therefore requires further prospective evaluation.Summary
Readily available epidemiologic risk factors can be used to predict susceptibility of Gram-negative organisms among patients with bacteraemia, using automated decision-making models. 相似文献94.
目的探讨氯胺酮麻醉前不同时间肌内注射阿托品对小儿呼吸道的影响。方法将2012年1月至2013年6月在廊坊市第四人民医院住院的100例患儿按随机数字表法分为两组:A组(50例)于氯胺酮麻醉前30~60 min肌内注射阿托品(0.02 mg/kg),B组(50例)阿托品(0.02 mg/kg)与氯胺酮同时间肌内注射。两组患儿均于氯胺酮肌内注射2~4 min后入室准备手术,术中观察记录两组患儿呼吸道和肺部的听诊变化及脉搏血氧饱和度(Sp O2)变化。结果 A组Ⅰ级(即呼吸道未受影响)44例,Ⅱ级以上(即呼吸道受到不同程度影响)6例,阳性率为12%(6/50);B组Ⅰ级33例,Ⅱ级以上17例,阳性率为34%(17∕50)。两组患儿呼吸道受影响程度的比较,差异有统计学意义(P<0.01)。结论小儿氯胺酮麻醉前30 min肌内注射阿托品,能有效降低氯胺酮对患儿呼吸道的影响,提高术中患儿的安全系数。 相似文献
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The most common cause of stroke in children with sickle cell anemia is infarction due to ischemia. In adults, however, stroke is most commonly hemorrhagic in nature. Other causes of stroke in patients with sickle cell disease are very rare. In this short communication, we describe a woman with sickle cell anemia responsive to hydroxyurea (HU) therapy who had primary stroke due to paradoxical embolization caused by a large atrial septal defect. Successful management of the stroke included surgical closure of the defect with trans-esophageal echocardiographic guidance. To the best of our knowledge, this is the first patient with sickle cell anemia and stroke due to congenital heart disease who did not require open heart surgery for successful management. 相似文献
98.
Do governing body and CSU nurses on clinical commissioning groups really lead a nursing agenda? Findings from a 2015 Survey of the Commissioning Nurse Leaders' Network Membership
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99.
Background Exenatide is an incretin mimetic licensed for treatment of Type 2 diabetes poorly controlled despite maximally tolerated doses of oral therapy. Similar in structure to the natural incretin hormone glucagon‐like peptide 1 (GLP‐1), it helps restore underlying pathophysiological abnormalities. Case report We report the successful use of exenatide, combined with insulin, in a 66‐year‐old woman initially diagnosed with Type 2 diabetes in 1989 but now exhibiting a Type 1 phenotype. Diet, lifestyle advice and oral glucose‐lowering agents were commenced but persisting poor control necessitated insulin therapy in 2005. She later presented twice in diabetic ketoacidosis, suggesting conversion to a Type 1 phenotype (postprandial C‐peptide < 94 pmol/l). Despite differing insulin regimens, control remained poor with frequent hyperglycaemic and hypoglycaemic excursions, severely impairing quality of life. Whilst an inpatient in 2007 [glycated haemoglobin (HbA1c) 10.2%, body mass index (BMI) 31.5 kg/m2] exenatide was commenced in an attempt to stabilize glycaemic control. Dramatic improvements were seen and continued. Eight months later, HbA1c had fallen by 2% with an 8‐kg weight loss and 10‐unit reduction in daily insulin dose. Quality of life dramatically improved. C‐peptide remains undetectable. Conclusions This patient with features of both Type 1 and Type 2 diabetes benefited greatly from exenatide with insulin therapy. The improvement seen in glycaemic control could not be attributable to enhanced insulin secretion but could be as a result of a combination of the other incretin effects (postprandial glucagon suppression, delayed gastric emptying and weight loss secondary to increased satiety) all improving insulin sensitivity, reducing insulin dose and smoothing control. 相似文献
100.
SIEW YEN HO Ph.D. JANET M. McCOMB M.D. CHRISTOPHER D. SCOTT M.B. ROBERT H. ANDERSON M.D. 《Journal of cardiovascular electrophysiology》1993,4(5):504-512
Conduction System in Dual AV Nodal Pathways. Introduction: Although the electrophysiologic criteria for dual atrioventricular nodal pathways are well established, the anatomical substrate is still unclear.
Methods and Results: We examined the hearts from 10 patients who had been studied electrophysiologically prior to cardiac transplantation. All 10 patients were male, aged 22 to 60years. Nine of the 10 patients had dual atrioventricular nodal pathways according to acceptedcriteria. Histologic studies of the atrioventricular conduction system showed normal structureof the atrioventricular node in all 10 hearts, with minor variations within the node in 3 cases, within the penetrating bundle in 3 cases, and within the nonbranching bundle in 3 cases. Theatrial approaches to the atrioventricular node were generally scanty in 6 hearts. The solitarycase that was shown electrophysiologically to lack dual pathways had no obvious difference inthe structure of the nodal area other than sparsity of transitional cells. We were unable tolocate any extranodal atrial tracts as described by other investigators.
Conclusion: The anatomical substrate for conduction over dual pathways may he too subtleto be detected by gross morphologic studies. Since dual pathways were unmasked in allpatients but one during electrophysiologic studies, it may be that the potential for these pathways is ubiquitous. 相似文献
Methods and Results: We examined the hearts from 10 patients who had been studied electrophysiologically prior to cardiac transplantation. All 10 patients were male, aged 22 to 60years. Nine of the 10 patients had dual atrioventricular nodal pathways according to acceptedcriteria. Histologic studies of the atrioventricular conduction system showed normal structureof the atrioventricular node in all 10 hearts, with minor variations within the node in 3 cases, within the penetrating bundle in 3 cases, and within the nonbranching bundle in 3 cases. Theatrial approaches to the atrioventricular node were generally scanty in 6 hearts. The solitarycase that was shown electrophysiologically to lack dual pathways had no obvious difference inthe structure of the nodal area other than sparsity of transitional cells. We were unable tolocate any extranodal atrial tracts as described by other investigators.
Conclusion: The anatomical substrate for conduction over dual pathways may he too subtleto be detected by gross morphologic studies. Since dual pathways were unmasked in allpatients but one during electrophysiologic studies, it may be that the potential for these pathways is ubiquitous. 相似文献