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INTRODUCTION: The quality of first-responder performance at the end of automated external defibrillator (AED) training may not predict the performance adequately during a real resuscitation attempt. METHODS: Between January and December 2000, we evaluated 67 resuscitation attempts in Amsterdam and surroundings, where police officers used an AED. We compared their performance with their assessment at the end of their ERC AED training course. One of the main goals of training was to deliver a shock within 90 s after switching the power on in the AED. RESULTS: We analysed 127 police officers working in 67 police-teams. The police officers had a mean age of 35 years (range 23-54 years), 73% was male. The interval between AED training and the first resuscitation attempt was a median of 4 months (range 1-13). 78% percent of the 67 teams consisted of two police officers who both were qualified as "competent" after the initial training. Successful completion of the course correlated well with good performance during a resuscitation attempt (p = 0.009). When measured switching the power on in the AED, 92% of the victims received a shock within 90 s. CONCLUSIONS: Successful training correlates well with successful performance in the field. Competence of a team may be better than competence of two separate individuals. 相似文献
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A short and effective training programme is an essential prerequisite for the use of automated external defibrillators (AED) by EMS providers and first responders. We evaluated a 3-h AED course based on the ERC requirements. METHODS: As part of a study evaluating the effectiveness of AEDs used by first responders (ARREST 4), we trained all police officers in the region of Amsterdam, the Netherlands. By means of a Basic Life Support (BLS) assessment at the beginning of the course and at the end, we evaluated whether BLS can be improved in a 3-h AED course. Through a combined BLS and AED assessment at the end of the course, we evaluated whether AED skills can be acquired sufficiently. BLS skills were measured with the Laerdal SkillMeter in evaluation mode. AED skills were assessed using 13 criteria. By means of logistic regression, we analysed the influence of student characteristics, such as age, gender, previous training, resuscitation experience and motivation for BLS and AED on BLS and AED skills acquisition. RESULTS: Between September 1999 and June 2000, 823 police officers were trained (76% male, mean age 36 (S.D. 9) years). BLS improved significantly (P < 0.001) in all criteria, except for hypoventilation (P < 0.001). After training, 89% of the students were able to use an AED safely and effectively. Self-confidence and motivation improved from 12 and 73% to 99 and 94% over the course (P < 0.001). Independent student characteristics influencing the success of the AED course were: previous BLS training, motivation before the course for an AED, and resuscitation experience that dated back for more than 12 months. CONCLUSION: The majority of police officers can be trained to use an AED safely and effectively within a 3-h AED course. During this course, they also improve on their BLS skills. Successful completion of the course depends in part on the student characteristics. 相似文献
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ASXL1 mutations are frequent and prognostically detrimental in CSF3R‐mutated chronic neutrophilic leukemia
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Michelle A. Elliott Animesh Pardanani Curtis A. Hanson Terra L. Lasho Christy M. Finke Alem A. Belachew Ayalew Tefferi 《American journal of hematology》2015,90(7):653-656
Colony stimulating factor 3 receptor gene (CSF3R) mutations have recently been associated with chronic neutrophilic leukemia (CNL). Fourteen patients with CSF3R‐mutated CNL (median age 67 years; 57% males) were screened for additional mutations; 8 (57%) and 5 (38%) harbored an ASXL1 and/or SETBP1 mutation (two patients expressed both), respectively. Two patients developed blastic transformation, both SETBP1‐mutated and ASXL1‐unmutated, whereas two other cases evolved into chronic myelomonocytic leukemia (CMML), both ASXL1‐mutated and SETBP1‐unmutated. Median survival was 23.2 months (10 deaths documented). On multivariable analysis mutated ASXL1 (P = 0.009; HR 19.6, 95% CI 2.1–184.1) and thrombocytopenia (P = 0.005; HR 28.8, 95% CI 2.8–298.2) were independently predictive of shortened survival. This study provides information on the natural history of CSF3R‐mutated CNL and identifies mutant ASXL1 and thrombocytopenia as risk factors for survival. The study also suggests pathogenetic roles for SETBP1 and ASXL1 mutations in disease evolution into blast phase disease and CMML, respectively. Am. J. Hematol. 90:653–656, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Shililu J Ghebremeskel T Mengistu S Fekadu H Zerom M Mbogo C Githure J Gu W Novak R Beier JC 《The American journal of tropical medicine and hygiene》2003,69(3):295-302
The spatial distribution of anopheline mosquito species was studied throughout Eritrea during the 1999-2001 malaria transmission seasons from October to December for the highlands and western lowlands and February to April for the coastal region. Of the 302 villages sampled, 59 were visited in both the first and second year. Overall, 13 anopheline species were identified, with the Anopheles gambiae complex predominating during the first year (75.6%, n = 861) and the second year (91.9%, n = 1,262). Intrazonal variation accounted for 90% of the total variation in mosquito distribution. Polymerase chain reaction results indicated that 99% (n = 1,309) of the An. gambiae s.l. specimens were An. arabiensis, indicating that this was the only member of the gambiae complex present. There was a high degree of aggregation of anophelines within zones and villages, with more than 80% of the total anophelines being collected from less than 20% of the villages and from only 10% of the houses sampled. At least 80% of the anopheline mosquitoes were collected from grass-thatched Agudo-type housing. Vector abundance showed an inverse relationship with elevation, with highest densities in the low-lying western lowlands. Multiple regression analysis of log-transformed mean density of An. arabiensis with rainfall and the normalized difference vegetation index (NDVI) (average NDVI, minimum NDVI, and maximum NDVI) showed that these independent variables were not significantly associated with mosquito densities (R2 = 0.058). Our study contributes to the basic understanding of the ecology and distribution of malaria vectors with respect to species composition and spatial heterogeneities both that could be used to guide vector control operations in Eritrea. 相似文献
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Sara J. Felts Virginia P. Van Keulen Michael J. Hansen Michael P. Bell Kathleen Allen Alem A. Belachew Richard G. Vile Julie M. Cunningham Tanya L. Hoskin V. Shane Pankratz Larry R. Pease 《Neoplasia (New York, N.Y.)》2015,17(4):348-357
Breast tumors in (FVB × BALB-NeuT) F1 mice have characteristic loss of chromosome 4 and sporadic loss or gain of other chromosomes. We employed the Illumina GoldenGate genotyping platform to quantitate loss of heterozygosity (LOH) across the genome of primary tumors, revealing strong biases favoring chromosome 4 alleles from the FVB parent. While allelic bias was not observed on other chromosomes, many tumors showed concerted LOH (C-LOH) of all alleles of one or the other parent on sporadic chromosomes, a pattern consistent with cytogenetic observations. Surprisingly, comparison of LOH in tumor samples relative to normal unaffected tissues from these animals revealed significant variegated (stochastic) deviations from heterozygosity (V-LOH) in every tumor genome. Sequence analysis showed expected changes in the allelic frequency of single nucleotide polymorphisms (SNPs) in cases of C-LOH. However, no evidence of LOH due to mutations, small deletions, or gene conversion at the affected SNPs or surrounding DNA was found at loci with V-LOH. Postulating an epigenetic mechanism contributing to V-LOH, we tested whether methylation of template DNA impacts allele detection efficiency using synthetic oligonucleotide templates in an assay mimicking the GoldenGate genotyping format. Methylated templates were systematically over-scored, suggesting that the observed patterns of V-LOH may represent extensive epigenetic DNA modifications across the tumor genomes. As most of the SNPs queried do not contain standard (CpG) methylation targets, we propose that widespread, non-canonical DNA modifications occur during Her2/neuT-driven tumorigenesis.Abbreviations: SNP, single nucleotide polymorphism; LOH, loss of heterozygosity; ASO, allele-specific oligonucleotide probe; LSO, locus-specific oligonucleotide probe 相似文献
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Polymorphonuclear elastase in the early diagnosis of complicated pyogenic pleural effusions 总被引:3,自引:0,他引:3
Alemán C Alegre J Segura RM Armadans L Suriñach JM Varela E Soriano T Recio J Fernández De Sevilla T 《Respiration; international review of thoracic diseases》2003,70(5):462-467
BACKGROUND: Polymorphonuclear elastase (PMN-E) is a neutrophilic marker that has been implicated in acute inflammatory responses. OBJECTIVES: To evaluate the accuracy of PMN-E in the diagnosis of complicated pyogenic effusions. PATIENTS AND METHOD: We studied 536 patients with pleural effusion of various etiologies. There were 125 pyogenic bacterial effusions (42 typical parapneumonic, 17 borderline complicated parapneumonic and 66 complicated parapneumonic or empyema), 83 tuberculous, 91 malignant, 42 paramalignant, 95 transudates, 28 miscellaneous and 72 effusions of unknown origin. Classic markers (pH, glucose, proteins, adenosine deaminase, LDH, leukocytes and differential count) and the PMN-E level were quantified in pleural fluid. The accuracy of PMN-E as an early marker in the diagnosis of complicated pyogenic infectious effusions was evaluated among pleural effusions that were not diagnosed with classic biochemical markers, radiological findings or Gram stain. Since results of pleural fluid culture and cytological examination are generally available after a 48-hour delay, they were not included as early markers in the initial diagnosis of pleural effusions. RESULTS: Early diagnosis of complicated pyogenic bacterial effusions was achieved in only 48 of 66 cases with classic markers. Among those that were not diagnosed with these parameters, a pleural PMN-E value >3,500 microg/l discriminated between complicated and noncomplicated pyogenic bacterial effusions with a sensitivity of 67% and a specificity of 97%. CONCLUSIONS: PMN-E is useful in the early diagnosis and management of complicated pyogenic infectious effusions, which may be delayed with classic markers. 相似文献
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