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141.
Technical failure (TF) continues to have a significant impact on the success of pancreas transplantation. We assessed risk factors for TF in 1115 pancreas transplants performed at a single center between 1998 and 2011. The overall TF rate was 10.2%. In a multivariable model, donor BMI ≥30 (HR 1.87, p = 0.005), donor Cr ≥2.5 (HR 3.16, p = 0.007), donor age >50 (HR 1.73, p = 0.082) and preservation time >20 h (HR 2.17, p < 0.001) were associated with TF. Bladder drainage of exocrine secretions was protective (HR 0.54, p = 0.002). We incorporated these factors in a Composite Risk Model. In this model the presence of one risk factor did not significantly increase risk of TF (HR 1.35, p = 0.346). Two risk factors in combination increased risk greater than threefold (HR 3.65, p < 0.001) and three risk factors increased risk greater than sevenfold (HR 7.66, p = <0.001). The analysis also identified many factors that were not predictive of TF, including previous transplants, immunosuppressive agent selection, and almost all recipient demographic parameters. While the model suggests that two or more risk factors predict TF, strategies to reduce preservation time may mitigate some of this risk.  相似文献   
142.
Solid organ transplantation is encumbered by an increasing number of waitlisted patients unrequited by the current organ supply. Preclinical models suggest that advances in deceased donor management and treatment can increase the quantity and quality of organs available for transplantation. However, the science of donor intervention and the execution of high quality, prospective, multi‐center, randomized‐controlled trials are restricted by a myriad of logistical challenges mired in regulatory and ethical ambiguity. By highlighting the obstacles to conducting research in deceased donors, this report endeavors to stimulate the creation of a multi‐disciplinary framework to facilitate the design, implementation and supervision of innovative trials that increase the quantity and/or quality of deceased donor organs.  相似文献   
143.

Introduction

Practitioners have noted a striking increase in the number of young patients under the age of 40 years old who develop esophageal adenocarcinoma. The aim of this study was to characterize the presentation, pathology and therapeutic outcome of these young patients.

Methods

The records of patients who presented to the Foregut Surgical Service at the University of Southern California with esophageal adenocarcinoma between 2000 and 2007 were retrospectively reviewed. The presentation, tumor stage and histology, therapy and outcome of the patients under the age of 40 were compared to those ≥40.

Results

Of the 374 patients reviewed, 20 (5 %) were under the age of 40. There were two patients in their second and 18 in their third decade of life. The youngest patient was 25 years old. A history of gastroesophageal reflux disease or Barrett’s esophagus was less common in patients <40 than in those ≥40; 15 and 5 % compared to 61 and 46 %. Similarly, patients <40 had a significantly longer time interval between the onset of symptoms and the diagnosis of their cancer than those ≥40; 4.5 vs. 2 months, p?=?0.04. They also had a higher prevalence of stage IV disease (30 vs. 6 %, p?=?0.0003), a shorter time to recurrence (9.5 vs.19 month, p?=?0.002), and a poorer median survival (17 vs. 43 month, p?=?0.04).

Conclusion

Esophageal adenocarcinoma in patients <40 years old commonly presents with an advanced stage of the disease and an associated poor survival. This is likely due to a low index of suspicion that dysphagia seen in younger patients is due to a malignancy.  相似文献   
144.
145.
Some recent studies suggest that errorless learning principles may be beneficial in memory rehabilitation for people with dementia, while others indicate that effortful processing may be more important. The present study compared the effects of four different learning techniques, varying in level of effort required and number of errors elicited, on free recall, cued recall and recognition of novel and previously known associations among people with early-stage dementia. Ten participants with a diagnosis of early-stage Alzheimer's, vascular or mixed dementia learned novel and previously familiar face–name associations with each of four techniques – vanishing cues, forward cues, target selection, and paired associate learning – in a within-subjects design. All conditions produced significant learning for both novel and familiar associations. There were no significant differences between conditions, although mean scores were slightly higher for errorful conditions. Reducing errors did not produce any benefits. Enhancing level of effort had no significant effects for familiar associations, but high-effort conditions were significantly more effective than low-effort conditions in facilitating cued recall of novel associations. The results confirm that memory rehabilitation techniques can produce significant benefits, but do not support the view that error reduction during learning facilitates greater improvement in early-stage dementia. Effort enhancement may be more important, especially when learning novel associations.  相似文献   
146.
Abstract

The development and initial validation of a measure designed to assess physical appearance-related verbal and nonverbal external feedback are described. The factor structure of the Feedback on Physical Appearance Scale (FOPAS) was replicable across two samples that completed the measure based on different instructional protocols. Reliability and convergence with measures of body image, eating disturbance, and global psychological functioning were acceptable. The results are discussed with regard to the potential importance of appearance-related feedback as a factor in the development and maintenance of body image and eating disturbance.  相似文献   
147.
148.

Purpose

To investigate agreement and reliability among clinicians when diagnosing low back-related leg pain (LBLP) in primary care consulters.

Methods

Thirty-six patients were assessed by one of six physiotherapists and diagnosed as having either leg pain due to nerve root involvement (sciatica) or referred leg pain. Assessments were video recorded. In part one, the physiotherapists each viewed videos of six patients they had not assessed. In part two, videos were viewed by another six health professionals. All clinicians made an independent differential diagnosis and rated their confidence with diagnosis (range 50–100 %).

Results

In part one agreement was 72 % with fair inter-rater reliability (K = 0.35, 95 % CI 0.07, 0.63). Results for part two were almost identical (K = 0.34, 95 % CI 0.02, 0.69). Agreement and reliability indices improved as diagnostic confidence increased.

Conclusion

Reliability was fair among clinicians from different backgrounds when diagnosing LBLP but improved substantially with high confidence in clinical diagnosis.
  相似文献   
149.
Three‐dimensional biomimetic scaffolds resembling the native extracellular matrix (ECM) are widely used in tissue engineering, however they often lack optimal bioactive cues needed for acceleration of cell proliferation, neovascularization, and tissue regeneration. In this study, the use of the ECM‐related protein Olfactomedin‐like 3 (Olfml3) demonstrates the importance and feasibility of fabricating efficient bioactive scaffolds without in vitro cell seeding prior to in vivo implantation. First, in vivo proangiogenic properties of Olfml3 were shown in a murine wound healing model by accelerated wound closure and a 1.4‐fold increase in wound vascularity. Second, subcutaneous implantation of tubular scaffolds coated with recombinant Olfml3 resulted in enhanced cell in‐growth and neovascularization compared with control scaffolds. Together, our data indicates the potential of Olfml3 to accelerate neovascularization during tissue regeneration by promoting endothelial cell proliferation and migration. This study provides a promising concept for the reconstruction of damaged tissue using affordable and effective bioactive scaffolds.  相似文献   
150.
B cells undergo a number of different developmental stages, from initial formation of their B cell receptor (BCR) genes to differentiation into antibody‐secreting plasma cells. Because the BCR is vital in these differentiation steps, autoreactive and exogenous antigen binding to the BCR exert critical selection pressures to shape the B cell repertoire. Older people are more prone to infectious disease, less able to respond well to vaccination and more likely to have autoreactive antibodies. Here we review evidence of changes in B cell repertoires in older people, which may be a reflection of age‐related changes in B cell selection processes.  相似文献   
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