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Objective: To evaluate the effects on ventricular function and volumes following right ventricular outflow tract reconstruction (RVOTR) with pulmonary homograft replacement (PVR) and percutaneous pulmonary valve implantation (PPVI) for predominant pulmonary regurgitation. This study was not intended to compare the two approaches. Methods: We prospectively examined 25 patients (mean age 21+/-13 years, 96% tetralogy of Fallot, 1/25 with conduit dysfunction) who had PVR with RVOTR for severe pulmonary regurgitation (PR), and 11 patients (mean age 20+/-9 years, 64% tetralogy of Fallot, 9/11 with conduit dysfunction) who underwent PPVI for predominant PR. Mean age at primary repair in both groups was 4.3+/-6.6 years. Magnetic resonance imaging was performed prior to, and 1 year following, interventions. Results: Before procedure, NYHA classification was similar in both groups 2.1+/-0.5. Following interventions, there was a significant reduction in RV volumes in both groups. In the surgical (PVR) group, RV end-diastolic volume (EDV) decreased from 151+/-49 to 97+/-32ml/m(2) (p<0.0001) whereas end-systolic volume (ESV) decreased from 80+/-43 to 46+/-23ml/m(2) (p<0.0001). In the PPVI group, RV EDV decreased from 106+/-27 to 89+/-25ml/m(2) (p=0.002) and RV ESV from 49+/-20 to 40+/-16ml/m(2) (p=0.034). Both groups had a significant improvement in RV (63+/-20 to 72+/-16ml/beat, p=0.003 (PVR group), 53+/-14 to 67+/-16ml/beat, p=0.030 (PPVI group)) and LV effective stroke volume (61+/-18 to 73+/-16ml/beat, p=0.001 (PVR group); 59+/-24 to 75+/-16ml/beat, p=0.009 (PPVI group)). Conclusions: Following either PVR with RVOTR or PPVI, there was a significant reduction in RV volumes and an improvement in RV function. Importantly, in both groups, LV effective SV increased, and this may be the parameter to judge the benefit of the procedure. These results also support PPVI as an extra dimension in complex RVOT management.  相似文献   
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Red squirrels are declining in the United Kingdom. Competition from, and squirrel poxvirus (SQPV) disease carried by, grey squirrels are assumed to be determining the decline. We analyse the incidence of disease and changes in distribution of the two species in Cumbria, from 1993 to 2003 and compare these to the predictions of an individual-based (IB) spatially explicit disease model simulating the dynamics of both squirrel species and SQPV in the landscape. Grey squirrels increased whilst red squirrels declined over 10 years. The incidence of disease in red squirrels was related to the time since grey squirrels arrived in the landscape. Analysis of rates of decline in red squirrel populations in other areas showed that declines are 17-25 times higher in regions where SQPV is present in grey squirrel populations than in those where it is not. The IB model predicted spatial overlap of 3-4 years between the species that was also observed in the field. The model predictions matched the observed data best when contact rates and rates of infection between the two species were low. The model predicted that a grey squirrel population control of >60% effective kill was needed to stop the decline in red squirrel populations in Cumbria.  相似文献   
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A recent publication showed the earliest signs of renal osteodystrophy in patients on maintenance hemodialysis (MHD) to occur in the tufts [1]. We present three patients on MHD, in two of whom the earliest unequivocal radiographic improvement was seen in the tufts. The third patient had been on MHD and, following subtotal parathyroidectomy, showed significant osseous improvement in the hands with relatively equal improvement in the tufts and middle phalanges. It appears that, with the use of routine primary or secondary magnification, the tufts are radiographically a highly sensitive site for both the early occurrence and improvement of osteodystrophy in patients on MHD. We are not aware of any previous publication pointing out exclusive improvement in the tufts in patients on MHD with virtually no change in the mid-phalanges. Two of these three cases illustrate that renal osteodystrophy is reversible by maintenance hemodialysis alone.  相似文献   
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BackgroundRadical cystectomy (Cx) is the standard of care for muscle-invasive bladder cancer (BCa). In locally advanced pT4 BCa the oncologic outcome is inexplicit but Cx may be necessary for palliation.ObjectivesThe aim of this retrospective study was to evaluate the outcomes of Cx performed in patients with locally advanced pT4 BCa and to identify patient subgroups with improved outcome.MethodsBetween 2008 and 2017, we identified 76 of 905 patients who underwent Cx for pT4 BCa at a single tertiary referral center. The physical patients’ status was estimated according to the American Society of Anesthesiologists (ASA) classification. For the classification of postoperative complication rates, the Clavien-Dindo grading was used. Time-to-event variables with log-rank statistics were calculated with the use of the Kaplan-Meier method.ResultsMedian age was 74 years (range 42–90). Preoperatively, the physical status was estimated poor in 40 (52%) patients (ASA-score of ≥3). Overall, 19 (25%) patients had pT4b BCa, 41 (54%) patients were lymph node positive (c/pN+) and 14 (18%) patients had distant metastases (c/pM+). Within 30 and 90 days after surgery, 21% and 30% of the patients, respectively, developed severe complications (Clavien-Dindo grade ≥3). Overall, 30- and 90-day mortality rates were 9% and 11%, respectively. Moreover, 86% and 75% of patients who died within 30 and 90 days after surgery, respectively, had an ASA-score ≥3. At a median postoperative follow-up of 8 months (range 0–85), 53 (70%) patients have died. During the follow-up period, 46% of the patients died due to progressive disease, 16% died of a noncancer-specific cause, and for 8% of the patients, the reason remains unknown. Median overall survival (OS) and cancer-specific survival were 13.0 and 16.0 months, respectively. In subgroup analyses ASA-score ≥3 and hemoglobin <11.7 g/dl was significantly associated with poor OS. No statistically significant differences were detected between subgroups.ConclusionCx performed in patients with locally advanced pT4 BCa is associated with an increased mortality rate within 90 days postoperatively. Our study revealed that the ASA-score is a relevant and easily available tool to rate the patient´s condition and estimate postoperative outcome.  相似文献   
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