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41.

Purpose

To evaluate the predictive and prognostic role as well as the clinical impact on decision-making of serum cholinesterase (ChoE) levels in patients treated with radical prostatectomy for clinically nonmetastatic prostate cancer.

Materials and methods

We conducted a retrospective analysis of our multi institutional database. Preoperative ChoE was evaluated as continuous and dichotomized variable using a visual assessment of the functional form of the association of ChoE with biochemical recurrence (BCR)-free survival. We assessed its association with perioperative clinicopathologic characteristics and outcomes. Multivariable models established its independent prognostic value for BCR. Cox proportional hazard coefficients were used to build nomograms for the prediction of early and late BCR. Decision curve analysis was used to assess the clinical impact on decision making of preoperative ChoE.

Results

In all, 6,041 patients were available for the analysis. Decreased ChoE was associated with higher biopsy Gleason score, preoperative PSA levels, pathologic Gleason score, pathological stage, lymph node metastasis, positive surgical margin, and lymphovascular invasion at radical prostatectomy (all P < 0.01). Preoperative ChoE ≤ 6.52 U/ml was associated with higher probability of BCR (HR 1.72, 95% CI 1.48–1.99, P < 0.001). Preoperative and postoperative multivariable models that adjusted for the effects of established clinicopathologic features confirmed its independent association with BCR. In decision curve analysis inclusion of preoperative ChoE did not improve the net benefit of preoperative and postoperative models for the prediction of BCR.

Conclusions

Despite independent association with clinicopathologic features and BCR, preoperative serum ChoE has no impact on clinical decision making. Future studies should investigate the possible relationship between ChoE activity and neoplastic cell transformation with a rational for targeting.  相似文献   
42.
The objectives of this study were to (1) to evaluate the shear bond strength (SBS) of two ceramic brackets when new and when rebonded following various bracket base conditioning methods, and (2) to determine bond failure mode relative to bracket base morphology. 100 Symetri ClearTM (SC) and 100 Radiance Plus® (RP) ceramic brackets were bonded to bovine incisors and divided into five groups: one group served as controls and four had brackets rebonded following conditioning by: no surface treatment, sealant, sandblasting, and flame then steam. SBS, adhesive remnant index, and bracket base morphology were evaluated. SBS showed no statistical difference between new and rebonded with no surface treatment or sealant (SC brackets) and with sealant or flame and steam (RP brackets). When comparing SC to RP, SBS was higher with SC, no surface treatment, and sandblasted groups. All groups had varying amounts of adhesive left on the tooth, with the sandblasted group having the most. SEM analysis showed that sandblasting damaged the retention features of bracket bases. In conclusion, when rebonded, the SBS of SC brackets that had no surface treatment and both SC and RP brackets that had sealant showed no significant differences to new brackets. Sandblasting damaged the retention features of SC and RP bracket bases, resulting in low SBS.  相似文献   
43.
International Urology and Nephrology - The study aims to objectively and precisely describe, in elderly dialysis patients from a single center, the prevalence of malnutrition and severe...  相似文献   
44.
Purpose: Adrenalectomy has the potential to cure or improve the control of hypertension in patients with primary hyperaldosteronism due to unilateral adrenal adenoma (Conn's syndrome). This study assesses the patients' perception of, and costs associated with, laparoscopic adrenalectomy for Conn's syndrome. Materials and Methods: Clinical, radiological, operative, and pathological data were collected on patients undergoing adrenalectomy for Conn's syndrome over 8-years period in a UK tertiary referral center. Results: Thirty-eight patients (17M:21F, age 34–79 yrs, median 54 yrs) operated between Jan2005-Sept2012 had lateralization based on CT scans (n = 30) and/or MRI scans (n = 18) and confirmed on selective adrenal venous sampling (n = 25). Laparoscopic adrenalectomy was performed in all patients, with two cases requiring conversion to open operation. Median operative time was 105 min (range: 27–315). Costs were estimated as £19k for preoperative investigations, £20k for in-hospital stay, £53k for operating theatre use and £29k for disposable surgical instruments, with average £3499/patient (national tariff for adrenalectomy in 2015/2016 £3624). Follow-up at a mean of 30 months postoperatively using a visual analogue scale and a standardized questionnaire showed significantly improved quality of life (QoL) post-operatively. Majority of patients (85%) reported taking none or fewer anti-hypertensive medications (median reduction of 2 antihypertensive drugs). All patients stated that they would definitely have the operation again in preference to anti-hypertensive medications and they would recommend the operation to friends/relatives. Conclusions: Laparoscopic adrenalectomy for Conn's syndrome has a positive impact on hypertension control, leads to improved QoL and its costs are covered in the NHS financial model.  相似文献   
45.
There are no clear recommendations regarding cirrhotic cardiomyopathy (CC) evaluation in patients with pre-transplant liver cirrhosis. The roles of new methods, tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) in the diagnosis and prognosis of cirrhotic cardiomyopathy remain controversial. We investigated the utility of TDI/STE parameters in cirrhotic cardiomyopathy diagnosis and also in predicting mortality in patients with liver cirrhosis. Left/right ventricular function was studied using conventional TDI (velocities) and STE (strain/strain rate). We assessed left ventricular diastolic dysfunction, graded into four new classes (I/Ia/II/III). Serum NTproBNP (N-terminal prohormone of brain natriuretic peptide), troponin I, β-crosslaps, QTc interval, arterial compliance and endothelial function were measured. Liver-specific scores (Child–Pugh, MELD, MELDNa) were computed. There was a 1-y follow-up visit to determine mortality. We observed resting biventricular diastolic myocardial dysfunction, not presently included in the definition of cirrhotic cardiomyopathy. We provided an improved characterization of cardiac dysfunction in patients with liver cirrhosis. This might change the current definition. However, the utility of STE/TDI parameters in predicting long-term mortality in patients with liver cirrhosis remains controversial.  相似文献   
46.
The echoic memory trace (EMT) refers to neuronal activity associated with the short-term retention of stimulus-related information, especially within the primary and association auditory cortex. Using magnetoencephalography it is possible to determine quantitatively the lifetime of the EMT. Previous studies assumed that each new stimulus drives the EMT to its full strength, which then passively decays. In this study we show the limitations of this assumption using trains of auditory stimuli designed specifically for computing the EMT lifetime and its contextual sensitivity. We estimated a time-dependent EMT using a data-driven approach, which allows contributions from a relatively wide area around the auditory cortex in our quantitative measures. We identified: (1) internally generated cortical activations during the silent period between stimuli well separated in time from each other, which had influence on the morphology of the neuromagnetic response to the next external stimulus; and (2) EMTs with different lifetimes that modulate the amplitude of the evoked responses at different latencies, suggesting the existence of multiple neural delay lines. Long EMT lifetimes were observed on the descending part of the M100 complex, which showed handedness and gender-dependent interhemispheric asymmetry. Specifically, all subjects showed longer EMT lifetimes on the left hemisphere, except left-handed males. Distributed source analysis of the data for one left- and one right-handed male subject identified a secondary generator in the right-handed subject, which was located posterior to the early primary generator and dominated the auditory response at late latencies, where EMT lifetime asymmetry was high. The identified multiple neural delay lines and their laterality may provide a link between macroneuronal activity and left hemisphere specialization for processing linguistic material.  相似文献   
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