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91.
92.
Salivary gland cancers include a diverse group of tumours with many histological subtypes which occur in both major and minor salivary glands. As a result of this heterogeneity and different sites of presentation, there have been no randomised controlled trials to evaluate the indications and efficacy of neck treatments by either surgery or radiotherapy for occult or apparent neck node metastases. Neck dissection is an important treatment strategy for neck metastases arising from major and minor salivary gland malignancy as well as being useful for disease staging. However, there is considerable controversy in how to manage the neck in these patients. In this review, we discuss the management of neck metastases relating to malignant salivary gland tumours.  相似文献   
93.
OBJECTIVE: This study was conducted to evaluate the 16-year efficacy of hepatitis B virus (HBV) vaccine in healthcare workers of Oil Company Hospital, Tehran, Iran. METHODS: Two hundred healthcare workers were enrolled in the study in 1989. All HBV markers were tested and those with positive HBV markers, positive antihepatitis C virus or anti-HIV were excluded from the study. The remaining participants received three doses of HBV vaccine and again all of our participants were reevaluated in 2005. Hepatitis B surface antigen (HBsAg), antihepatitis B surface antibody (anti-HBsAb), and antihepatitis B core antibody (anti-HBcAb) were checked in all participants and those with anti-HBcAb above 10 IU/l were excluded from the final evaluation. RESULTS: No participant was positive for HBsAg in either 1989 or 2005. Protective levels of anti-HBsAb were absent in all participants in 1989, but present in 67 (80.7%) participants in 2005 (P<0.001). Anti-HBsAb titer after vaccination was significantly higher in female participants than in male participants (P=0.01). Mean anti-HBsAb titer was 640+/-411.7 IU/l (range: 2-1000 IU/l) and the lowest protective titer was 12 IU/l. CONCLUSION: According to our results, 80.7% of our participants had a protective titer of anti-HBsAb 16 years after vaccination. Although all anti-HBc positive participants were free of clinical hepatitis and were negative for HBsAg, hepatitis B vaccination was proved to be highly effective in preventing clinically significant infection and chronic carrier status up to 16 years after the primary vaccination. Hence, HBV revaccination may not be mandatory in healthcare workers, according to their sufficient long-term level of anti-HBsAb.  相似文献   
94.
Sphingosine-1-phosphate (S1P), a bioactive lipid, is a potent candidate for treatment of ischemic vascular disease. However, designing biomaterial systems for the controlled release of S1P to achieve therapeutic angiogenesis presents both biological and engineering challenges. Thus, the objective of this study was to design a hydrogel system that provides controlled and sustained release of S1P to establish local concentration gradients that promote neovascularization. Alginate hydrogels have been extensively studied and characterized for delivery of proangiogenic factors. We sought to explore if chitosan (0, 0.1, 0.5, or 1%) incorporation could be used as a means to control S1P release from alginate hydrogels. With increasing chitosan incorporation, hydrogels exhibited significantly denser pore structure and stiffer material properties. While 0.1 and 0.5% chitosan gels demonstrated slower respective release of S1P, release from 1% chitosan gels was similar to alginate gels alone. Furthermore, 0.5% chitosan gels induced greater sprouting and directed migration of outgrowth endothelial cells (OECs) in response to released S1P under hypoxia in vitro. Overall, this report presents a platform for a novel alginate-chitosan hydrogel of controlled composition and in situ gelation properties that can be used to control lipid release for therapeutic applications.  相似文献   
95.
96.

Introduction

Intraorifice barriers (IOBs) are usually used before internal bleaching for coronal sealing and the prevention of cervical resorption. The aim of this study was to investigate the effect of different IOBs on the fracture resistance (FR) of endodontically treated anterior teeth bleached with various bleaching agents (BAs).

Methods

After performing root canal treatment for 72 extracted bovine upper incisors, the coronal 3 mm of gutta-percha was removed, and samples were classified into 3 based on the type of IOB: calcium-enriched mixture, mineral trioxide aggregate, and resin-modified glass ionomer. After applying IOBs, samples of each group were subdivided into 4 based on the BA: carbamide peroxide 45% (CP), hydrogen peroxide 35% (HP), sodium perborate (PB), and distilled water as the control. At the end of bleaching, the access cavities were restored with composite resin. The FR was measured with a universal testing machine at a crosshead speed of 5 mm/min. The data were analyzed using 2-way analysis of variance and least significant difference post hoc tests (P < .05).

Results

The effect of BAs on the FR was significant (P < .05); however, the effect of the IOB and the interactive effect of these variables were not significant (P > .05). The FR in the HP and PB groups was significantly different from the control (P < .05) but that of CP was not significantly different from the control (P > .05).

Conclusions

Mineral trioxide aggregate and calcium-enriched mixture act similarly to resin-modified glass ionomer as an IOB. CP, unlike HP and PB, did not significantly decrease the FR.  相似文献   
97.
Type 1 Gaucher disease (GD1) is an inherited lysosomal storage disease, which is often managed by enzyme replacement therapy (ERT). The bone response to ERT is usually slower than visceral and hematological responses. There is uncertainty as to whether an increase in the dosage of ERT has a beneficial effect. The aim of our study was to determine whether or not there is sufficient evidence to make a definitive statement about the effects of ERT and substrate reduction therapy (SRT) on bone marrow infiltration and bone mineral density (BMD) in GD1. We conducted a systematic review of all studies examining the effects of ERT and SRT on bony complications of GD1 published before July 2008. The studies were identified by a computerized search with use of Medline, Embase, The Cochrane Database of Systematic Reviews, The Cochrane Central Register of Controlled Trials (CCTR), and bibliographies of papers subsequently retrieved from the search. Three hundred studies were grouped according to whether they deal with the natural history of GD1 or therapeutic issues, and 17 studies were included in the review. The results from our systematic review suggest that further investigations, such as better analysis of the Gaucher Registry, are needed on the effects of ERT and SRT on bony complications of GD1. Studies on the effects of the newly identified velaglucerase and the plant-derived glucocerebrosidase on bony complications of GD1 are also needed.  相似文献   
98.
Background: Autogenous intramembranous bone graft present several advantages such as minimal resorption and high concentration of bone morphogenetic proteins. A method for measuring the amount of bone that can be harvested from the symphysis area has not been reported in real patients. Purpose: The aim of the present study was to intrasurgically quantitate the volume of the symphysis bone graft that can be safely harvested in live patients and compare it with AutoCAD® (version 16.0, Autodesk, Inc., San Rafael, CA, USA) tomographic calculations. Materials and Methods: AutoCAD software program quantitated symphysis bone graft in 40 patients using computerized tomographies. Direct intrasurgical measurements were recorded thereafter and compared with AutoCAD data. The bone volume was measured at the recipient sites of a subgroup of 10 patients, 6 months post sinus augmentation. Results: The volume of bone graft measured by AutoCAD averaged 1.4 mL (SD 0.6 mL, range: 0.5–2.7 mL). The volume of bone graft measured intrasurgically averaged 2.3 mL (SD 0.4 mL, range 1.7–2.8 mL). The statistical difference between the two measurement methods was significant. The bone volume measured at the recipient sites 6 months post sinus augmentation averaged 1.9 mL (SD 0.3 mL, range 1.3–2.6 mL) with a mean loss of 0.4 mL. Conclusion: AutoCAD did not overestimate the volume of bone that can be safely harvested from the mandibular symphysis. The use of the design software program may improve surgical treatment planning prior to sinus augmentation.  相似文献   
99.
Prostate cancer is the most common visceral cancer in men. Many studies have shown that nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the risk of prostate cancer. We systematically searched all relevant databases (MEDLINE, EMBASE, The Cochrane Collaboration, CINAHL, Database of Abstracts of Review of Effects and ACP Journal Club) to March 2008. We also explored bibliographies of the articles, pertinent journals and conferences. We selected relevant articles according to predefined inclusion criteria by 2 independent reviewers. We used both fixed and random-effect models for meta-analysis. We performed subgroup and sensitivity analysis based on predefined variables. From 962 extracted articles, 20 met the inclusion criteria with a total of 25 768 participants. All the studies had an observational design. There was a statistically significant protective effect for NSAIDs on risk of prostate cancer (odds ratio [OR] 0.92, 95% confidence interval [CI] 0.86–0.97). Subgroup analysis did not show any effect of study design or quality score on the results. There was a small but statistically significant protective effect for acetylsalicylic acid (ASA) (OR 0.95, 95% CI 0.91–1.00). Exposure to non-ASA NSAIDs was associated with a slightly reduced likelihood of prostate cancer (OR 0.92, 95% CI 0.85–1.00). With the available data, we were not able to determine an optimum dosage for NSAIDs. We conclude that taking NSAIDs may reduce the risk of prostate cancer. Nevertheless, the effect is small.  相似文献   
100.
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