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Our objectives were to study the prevalence, risk factors for carriage, and transmission dynamics of extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae (ESBLPE) in a national survey of cattle. This was a point prevalence study conducted from July to October 2013 in Israel. Stool samples were collected from 1,226 cows in 123 sections on 40 farms of all production types. ESBLPE were identified in 291 samples (23.7%): 287 contained Escherichia coli and 4 contained Klebsiella pneumoniae. The number of ESBLPE-positive cows was the highest in quarantine stations and on fattening farms and was the lowest on pasture farms (P = 0.03). The number of ESBLPE-positive cows was the lowest in sections containing adult cows (age, >25 months) and highest in sections containing calves (age, <4 months) (P < 0.001). Infrastructure variables that were significant risk factors for ESBLPE carriage included crowding, a lack of manure cleaning, and a lack of a cooling (P < 0.001 for each), all of which were more common in sections containing calves. Antimicrobial prophylaxis was given almost exclusively to calves and was associated with a high number of ESBLPE carriers (P < 0.001). The 287 E. coli isolates were typed into 106 repetitive extragenic palindromic (REP)-PCR types and mostly harbored blaCTX-M-1 or blaCTX-M-9 group genes. The isolates on the six farms with ≥15 isolates of ESBLPE were of 4 to 7 different REP-PCR types, with one dominant type being harbored by about half of the isolates. Fourteen types were identified on more than one farm, with only six of the farms being adjacent to each other. The prevalence of ESBLPE carriage is high in calves in cowsheds where the use of antimicrobial prophylaxis is common. ESBLPE disseminate within cowsheds mainly by clonal spread, with limited intercowshed transmission occurring.  相似文献   
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The reliable change index (RCI) expresses change relative to its associated error, and is useful in the identification of post-operative cognitive dysfunction (POCD). This paper examines four common RCIs that each account for error in different ways. Three rules incorporate a constant correction for practice effects and are contrasted with the standard RCI that had no correction for practice. These rules are applied to 160 patients undergoing coronary artery bypass graft (CABG) surgery who completed neuropsychological assessments preoperatively and 1 week post-operatively using error and reliability data from a comparable healthy non-surgical control group. The rules all identify POCD in a similar proportion of patients, but the use of the within subject standard deviation, expressing the effects of random error, as an error estimate is a theoretically appropriate denominator when a constant error correction, removing the effects of systematic error, is deducted from the numerator in a RCI.  相似文献   
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We compared our standard NIH (extended incubation) crossmatch (XM) with antihuman globulin (AHG) and flow cytometry XMs and correlated the results with rejection episodes and graft survivals. For 89 CsA-Pred, primary renal allograft recipients, AHG and/or FCXM results did not improve on the NIH-XM-negative (NEG) graft survival results, whether testing pretransplant or historical (Hx) sera. Similarly, there was no association of a positive (POS) AHG or FCXM with increased rejection episodes in these primary recipients. However, for retransplant (Re-Tx) recipients a neg AHG or FCXM did discriminate fewer rejections and an improved graft survival compared with the NIH-XM-neg. results. The overall one-year graft survival for the 47 Re-Tx recipients studied herein was 66% (based on a neg pre-Tx NIH-XM). Pre-Tx AHG-NEG, Re-Tx recipients displayed an improved graft survival compared with NIH-XM NEG recipients (77% vs. 66%, P less than 0.05) and with AHG-POS recipients (77% vs. 47%, P less than 0.05). Similarly, pre-Tx, FCXM-NEG, Re-Tx recipients displayed improved graft survivals compared with NIH-XM-NEG recipients (83% vs. 66%, P less than 0.05) and FCXM-POS recipients (83% vs. 48%, P less than 0.05). Re-Tx recipients displaying a POS AHG and/or FCXM experienced a significantly greater number of rejections than NEG-XM recipients (P less than 0.05, respectively). The AHG and FCXM results correlated with rejections and graft survivals whether testing pre-Tx or Hx high-PRA sera. Re-Tx recipients who were AHG-XM-NEG but FCXM-POS, experienced more rejection episodes than recipients who displayed a negative XM reactivity for both AHG and FCXM (P less than 0.02), but with no resulting differences in graft survival. HLA matching, pre-Tx blood transfusions and PRA did not impact on these crossmatch and graft survival results. Use of AHG and/or FCXMs for Re-Tx, but not primary, recipients should help to improve graft survival for these high-risk recipients.  相似文献   
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