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34.

Purpose  

The tumor suppressor gene PTEN negatively regulates Akt, a downstream mediator phosphoinositol 3-kinase. Several studies have reported the role of PTEN gene in Akt downregulation and apoptosis induction in different cancers and cell lines. However, the role of loss of PTEN expression in Akt activation and spontaneous apoptosis in oral squamous cell carcinoma clinical specimens is not well established.  相似文献   
35.

Background

Elective temporary clipping (ETC) is increasingly used in surgery for aneurysms. This study was to assess whether the impact of ETC on intraoperative aneurysmal rupture (IAR) translates into neurological outcome.

Methods

Patients who underwent surgery for ruptured anterior circulation aneurysms were prospectively studied for various factors related to ETC, IAR and neurological outcome at 3 months. Univariate and multivariate analyses were performed using SPSS20.

Results

Of the total 273 ruptured aneurysm surgeries studied, IAR was observed in only six out of 132 aneurysms (4.5 %) who had ETC, compared with 78 out of 141 (55.3 %) without ETC (p?<?0.001). Aneurysms complicated by IAR had significantly longer clipping time (8.3 min) compared with those without IAR (1.9 min) (p?<?0.001). IAR had significant association with unfavorable outcome (38 % vs. 24 %) (p?=?0.02). Patients with ETC had significantly shorter clipping time (2.9 min) compared with those without ETC (4.8 min) (p?=?0.02). Unfavorable outcome was noted in 30 out of 132 with ETC (23 %), compared with 48 out of 141 without ETC (34 %) (p?=?0.04). This beneficial effect was nonsignificantly greater in younger and good clinical grade patients. While episodes of ETC within clipping time of 20 min did not show significant difference in outcome, repeated rescue clipping (45 % unfavorable outcome, p?=?0.048) and total clipping time of at least 20 min (75 % unfavorable outcome, p?=?0.008) had significant impact on outcome. In multivariate analysis, the use of ETC (p?=?0.027) and total temporary clipping less than 20 min (p?=?0.049) were noted to result in significantly better outcome, independent of other factors.

Conclusions

The use of ETC decreased the occurrence of IAR and the total clipping time, thereby leading to significantly better outcome, independent of other factors. While repeated elective clipping within total clipping time of 20 min did not influence outcome, repeated rescue clipping and total clipping time of at least 20 min had significant impact on outcome.  相似文献   
36.

Introduction

Previous studies, including research published more than 10 years ago in Northern Alberta, have demonstrated improved outcomes with increased surgical volume and subspecialisation in the treatment of rectal cancer. We sought to examine contemporary rectal cancer care in the same region to determine whether practice patterns have changed and whether outcomes have improved.

Methods

We reviewed the charts of all patients with rectal adenocarcinoma diagnosed between 1998 and 2003 who had a potentially curative resection. The main outcomes examined were 5-year local recurrence (LR) and disease-specific survival (DSS). Surgeons were classified into 3 groups according to training and volume, and we compared outcome measures among them. We also compared our results to those of the previous study from our region.

Results

We included 433 cases in the study. Subspecialty-trained colorectal surgeons performed 35% of all surgeries in our study compared to 16% in the previous study. The overall 5-year LR rate and DSS in our study were improved compared to the previous study. On multivariate analysis, the only factor associated with increased 5-year LR was presence of obstruction, and the factors associated with decreased 5-year DSS were high-volume noncolorectal surgeons, presence of obstruction and increased stage.

Conclusion

Over the past 10 years, the long-term outcomes of treatment for rectal cancer have improved. We found that surgical subspecialization was associated with improved DSS but not LR. Increased surgical volume was not associated with LR or DSS.  相似文献   
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Heart failure (HF) is a common cause of pleural effusion. Atrial tachyarrhythmias (ATa) can precipitate HF. ATa precipitating unilateral pleural effusion (PLE) has not been reported. We report a case of ATa in a patient with hypertrophic cardiomyopathy with recurrent unilateral rightsided PLE and resolution of effusion with catheter ablation of the arrhythmia.  相似文献   
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Specular microscopy is a noninvasive diagnostic tool that allows for in vivo evaluation of corneal endothelium in health and various diseased states. Endothelial imaging helps in the diagnosis and management of several endothelial disorders. The review focuses on the principles of specular microscopy, limitations of endothelial imaging, and its interpretation in common conditions seen in the clinical practice. A thorough PubMed search was done using the keywords specular microscopy, corneal endothelium, and endothelial imaging.  相似文献   
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