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991.
Statement of problemPatients and clinicians are aware of the efficacy and benefits of complete dentures, but evidence regarding their longevity is limited.PurposeThe purpose of this systematic review was to examine the literature describing the longevity of complete dentures and to review variations in longevity by denture type and duration of follow-up.Material and methodsFour electronic databases were searched by using key terms: MEDLINE, CINAHL (EBSCO), Dentistry and Oral Sciences Databases, and The Cochrane Library. Studies meeting the inclusion criteria were reviewed according to an established protocol and data extracted. Reference lists of identified studies were examined. Risk of bias was assessed by using the AXIS tool. Weighted means and weighted standard deviations were calculated. Pooled complete denture failure proportions were estimated by using random effects models based on the DerSimonian and Laird method.ResultsThe search yielded 21 607 unique abstracts, of which 273 met the inclusion criteria. Assessment of the full-text articles reduced this number to 42. Of these, 24 studies were rated as having low risk of bias and 18 as very low. The weighted mean ±standard deviation longevity of maxillary complete dentures was 10.3 ±3.8 years, of mandibular dentures was 8.6 ±2.6 years, and of both maxillary and mandibular dentures was 10.8 ±4.7 years. The pooled failure proportion for complete dentures observed for 2 years or less was 0.05 (95% confidence interval [CI]: 0.00-0.10), 5 to 6 years was 0.12 (95% CI: 0.08-0.16), and 10 years or more was 0.41 (95% CI: 0.28-0.53).ConclusionsComplete dentures, fabricated primarily in university settings, were found to have a weighted mean ±standard deviation longevity of 10.1 ±4.0 years. The failure rate of these prostheses increased with denture age, and the longevity of maxillary dentures was greater than that of mandibular dentures.  相似文献   
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Computational simulations of stenting procedures in idealized geometries can only provide general guidelines and their use in the patient-specific planning of percutaneous treatments is inadequate. Conversely, image-based patient-specific tools that are able to realistically simulate different interventional options might facilitate clinical decision-making and provide useful insights on the treatment for each individual patient.The aim of this work is the implementation of a patient-specific model that uses image-based reconstructions of coronary bifurcations and is able to replicate real stenting procedures following clinical indications. Two clinical cases are investigated focusing the attention on the open problems of coronary bifurcations and their main treatment, the provisional side branch approach. Image-based reconstructions are created combining the information from conventional coronary angiography and computed tomography angiography while structural finite element models are implemented to replicate the real procedure performed in the patients.First, numerical results show the biomechanical influence of stents deployment in the coronary bifurcations during and after the procedures. In particular, the straightening of the arterial wall and the influence of two overlapping stents on stress fields are investigated here. Results show that a sensible decrease of the vessel tortuosity occurs after stent implantation and that overlapping devices result in an increased stress state of both the artery and the stents. Lastly, the comparison between numerical and image-based post-stenting configurations proved the reliability of such models while replicating stent deployment in coronary arteries.  相似文献   
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Background

Since scarce data exist on the pathogenesis of nasopharyngeal carcinoma in Caucasian patients, we attempted to elucidate the responsible molecular pathways in this patient population.

Methods

Formalin-fixed paraffin-embedded tumor tissue samples from 107 patients, diagnosed with locally-advanced nasopharyngeal carcinoma and treated with chemotherapy or chemo-radiotherapy, were analyzed by immunohistochemistry for the expression of the following proteins: E-cadherin, P-cadherin, Fascin-1, Cyclin D1, COX-2, EGFR, VEGF-A, VEGF-C, VEGFR-2, VEGFR-3, ERCC1, p53, p63, Ki67, MAPT, phospho-p44/42MAPK, PTEN, phospho-AKT, phospho-mTOR, and phospho-GSK-3β. EBER status was assessed by in situ hybridization. The majority of the cases were included in tissue microarray. All stains were performed and assessed centrally by two pathologists. The median follow-up time was 76.8 (42.3 – 99.2) months.

Results

Biomolecules expressed in >90% of cases were: p53, COX-2, P-cadherin, EBER, phospho-GSK-3β, and Fascin-1. WHO II+III tumors were more frequently EBER & PTEN positive and VEGF-A negative. Advanced age was significantly associated with positive phospho-GSK-3β and ERCC1 expression; male gender with positive phospho-AKT and phospho-p44/42MAPK; and worse performance status (1 or 2) with negative Ki67, ERCC1, PTEN, and phospho-mTOR expression. Earlier disease stage was closely associated with p63, MAPT, PTEN, and Cyclin D1 positivity. Univariate Cox regression analysis highlighted Cyclin D1 as a negative prognostic factor for disease-free survival (p=0.034) and EBER as a positive one for overall survival (p=0.048). In multivariate analysis, advanced age and stage, poor performance status, and positive ERCC1 emerged as predictors of worse disease-free and overall survival, as opposed to positive phospho-mTOR. Clustering analysis defined two protein-expression groups being predictive of better overall survival (p=0.043).

Conclusions

Our study is the first to examine the activation and interaction of established biomolecules and signaling pathways in Caucasian NPC patients in an effort to reveal new therapeutic targets.  相似文献   
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The aim of our study is to compare the results of emergency surgery versus conservative treatment with interval surgery in patients diagnosed with appendiceal mass and abscess. A retrospective review of 48 patients with appendiceal mass and abscess treated from January 2002 to January 2013 at General Surgery Department of Kipshidze Central University Hospital was performed. Patients with emergency surgery were compared to patients treated by nonoperative management with interval surgery. Demographics, clinical profile, and operative outcomes were studied. The emergency surgery group included 25 patients, and the interval surgery group included 23 patients. The clinical characteristics of the emergency surgery and interval surgery groups were not statistically different. In the emergency surgery group, an open appendectomy was performed on 17 patients, and colonic resections (ileocecectomy or right hemicolectomy) were performed on 8 patients. In the interval surgery group, an open appendectomy was performed on 21 patients, and colonic resections were performed on 2 patients. There were no statistical differences in types of surgery, postoperative complications, operation time without colonic resections, and postoperative hospitalization period among these 2 groups. Operation time with colonic resections was of greater duration in the emergency surgery group than in the interval surgery group (P = 0.04). Both treatment methods for appendiceal mass and abscess have the same results. The surgeon must consider clinical symptoms and results of investigations in each particular case when choosing an appropriate treatment method. Prospective randomized controlled trials are required for comparing the results of all 3 treatment methods of appendiceal mass.Key words: Appendicitis, Mass, Abscess, Appendectomy, Ileocecectomy, Right hemicolectomyAcute appendicitis is one of the most frequent acute surgical pathologies. The inflammation in acute appendicitis may sometimes be fixed by the patient''s own defense mechanisms, by the formation of an inflammatory mass (an appendiceal phlegmon) or a circumscribed abscess (an appendiceal abscess), often presenting as a palpable mass days following the onset of symptoms. This complication occurs in 2 to 7% of all cases of appendicitis.1,2Management of appendiceal mass and abscess is either operative or conservative. More evidence is needed to identify which method is superior.1 Immediate appendectomy may be technically demanding because of the distorted anatomy and difficulties in closing the appendiceal stump due to the inflamed tissues. According to the aforementioned, the operation could be finished with colonic resections (ileocecectomy or right hemicolectomy).24Conservative management with interval appendectomy has traditionally remained the gold standard management. The need for interval appendectomy after a successful nonsurgical treatment has recently been questioned as the risk of recurrence is relatively small.57 After successful nonsurgical treatment of an appendiceal mass, the true diagnosis is uncertain in some cases and underlying diagnosis of cancer or Crohn''s disease (CD) may be delayed.1,8,9The aim of our study is to compare the results of emergency surgery versus conservative treatment followed by elective surgery in patients diagnosed with appendiceal mass and abscess.  相似文献   
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