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Dental restorations fail for a variety of reasons. Secondary caries is one of the primary causes of failure of dental restorations. One method for reducing frequency and severity of this problem is the use of fluoride containing restorative materials. The ability of a material to inhibit secondary caries formation is an important clinical therapeutic property. This investigation assessed the capacity of esthetic restorative materials to resist caries in vitro. Class V cavities were prepared in buccal and lingual surfaces of 50 extracted sound third molars. The occlusal and gingival cavosurface margin of each preparation was on enamel surface. The five materials were used: Conventional glass ionomer cement Ceramfil beta (PSP), two polyacid modified resin composites Compoglass (Vivadent) and Dyract (Dentsply/DeTrey), non fluoride releasing composite resin Valux Plus (3M) and fluoride releasing composite resin Tetric (Vivadent). After 10 weeks in an acid gel for caries-like lesion formation, the teeth were sectioned occluso-gingivally through the middle of the restorations and examined by polarized light microscopy, while immersed in water. The statistical analysis of the results showed that secondary caries initiation and progression might be reduced significantly when fluoride-containing materials were placed. The conventional glass ionomer cement (Ceramfil beta) provided the highest protection against caries attack and the non-fluoride releasing composite resin (Valux Plus) restoration provided the least (p<0.05).  相似文献   
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PURPOSE: To evaluate the effect of saliva contamination on the microleakage of an etch-and-rinse adhesive and a self-etching adhesive. MATERIALS AND METHODS: Class V cavity preparations at the cementoenamel junction were made on the buccal and lingual surfaces of 40 freshly extracted human molars. The teeth were randomly assigned into two groups for different adhesives: Group I, Single Bond (two-step etch-and-rinse adhesive) and Group II, Futura Bond NR (one-step self-etching adhesive). The adhesive materials were applied according to their manufacturers' recommendations. The specimens were then further subdivided into five subgroups (A-E; n = 8): group A, contamination before adhesive curing; group B, contamination before adhesive curing and re-application of adhesive; group C, contamination after adhesive curing; group D, contamination after adhesive curing and re-application of adhesive; and group E, no contamination (control). Contamination of adhesive surfaces was performed with fresh natural saliva and the saliva was removed by a gentle air blast. The specimens were restored with Z250 hybrid composite. After thermocycling (500x, 5 degrees C to 55 degrees C) and immersion in 0.5% basic fuchsin, the dye penetration was evaluated under a stereomicroscope. Statistical analysis was performed with the Kruskal-Wallis test at p < 0.05. RESULTS: No statistically significant differences were found among the contamination subgroups on the enamel or on the dentin for either group (p > 0.05). There was no significant difference in leakage between Group I and Group II for any subgroup (p > 0.05). CONCLUSION: Contamination of adhesives with saliva before and after adhesive curing did not worsen the microleakage of the two-step etch-and-rinse adhesive Single Bond or the one-step self-etching adhesive Futura Bond NR.  相似文献   
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Recently, longitudinal stent deformation (LSD) has been reported increasingly. Even though the reported cases included almost all stent designs, most cases were seen in the Element? stent design (Boston Scientific, Natick, MA, USA). It is considered that stent design, lesion and procedural characteristics play a role in the etiology of LSD. Yet, the effect of LSD on long-term clinical outcomes has not been studied well. Element stents implanted between January 2013 and April 2015 in our hospital were examined retrospectively. Patients were grouped into two according to the presence of LSD, and their clinical, lesion and procedural characteristics were studied. Twenty-four LSD’s were detected in 1812 Element stents deployed in 1314 patients (1.83?% of PCI cases and 1.32?% of all Element stents). LMCA lesions (16.7?% vs 1.6?%, p?<?0.001), complex lesions (75?% vs 35.1?%, p?<?0.001), bifurcation lesions (37.5?% vs 18.3?%, p?=?0.017), ostial lesions (33.3?% vs 12.8?%, p?=?0.003), using of extra-support guiding catheter (54.2?% vs 22.3?%, p?<?0.001) and extra-support guidewire (37.5?% vs 16.2?%, p?=?0.005) were found to be more frequent in cases with LSD than in cases without it. In addition, the number of stents, stent inflation pressure and the use of post-dilatation were significantly different between the two groups. Two patients had an adverse event during the follow-up period. LSD is a rarely encountered complication, and is more common in complex lesions such as ostial, bifurcation and LMCA lesions. The use of extra-support guiding catheter, extra-support guidewires and low stent inflation pressure increases the occurrence of LSD. Nevertheless, with increased awareness of LSD and proper treatment, unwanted long-term outcomes can be successfully prevented.  相似文献   
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Purpose  

Adequate graft fixation over a certain time period is necessary for successful cartilage repair and permanent integration of the graft into the surrounding tissue. The aim of the present study was to test the primary stability of a new cell-free collagen gel plug (CaReS?-1S) with two different graft fixation techniques over a simulated early postoperative period.  相似文献   
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Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? This study reflects the second largest series of revascularization operations performed in different etiologic and risk groups with the longest follow up. Beyond that this is the only study in which CC‐EMG techniques were used preoperatively to exclude some patients and to predict postoperative success in penile revascularization.

OBJECTIVE

? To determine the overall long‐term success of penile revascularization surgery in the treatment of vasculogenic erectile dysfunction (ED) and also to investigate the effect of risk factors on the results of a modified Furlow–Fisher technique.

PATIENTS AND METHODS

? Between 1999 and 2010, 125 men with a mean (sd , range) age of 43.2 (11.3, 23–69) years underwent penile revascularization surgery. In all, 110 men completed the long‐term follow‐up with a mean follow‐up of 73.2 months. ? Diagnostic evaluations, penile colour Doppler ultrasonography, corpus cavernosum electromyography, and cavernosometry, were performed in all the men before surgery. ? The efficacy of the surgery was assessed as improvement or failure according to the change in the five‐item version of the International Index of Erectile Function (IIEF‐5). A ≥5 point increase in the IIEF‐5 score during the latest patient visit after surgery compared with that before surgery was regarded as improvement (surgical success).

RESULTS

? The mean (sd ) IIEF‐5 score was 7.3 (3.2) before surgery and at the end of the follow‐up periodit was 16.8 (3.1). ? The success rates were 81.8% at 3 months, 77.2% at 1 year, 70% at 2 years, 66.3% at 3 years and 63.6% at 5 years after surgery in the men who achieved a no‐ED threshold score of >26 in the IIEF‐15. ? The success rate was the highest in the men with no risk factors (92.8%). ? Seven patients (6.36%) showed signs of glans hypervascularization as a major complication.

CONCLUSIONS

? Penile revascularization surgery has not been widely used by urologists probably due to the technical difficulties and the use of phosphodiesterase type 5 inhibitors. ? However, with reported high rates of noncompliance or failure of oral pharmacotherapy it seems likely that this surgery will become more popular in the near future.  相似文献   
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The simple yet powerful technique of induced pluripotency may eventually supply a wide range of differentiated cells for cell therapy and drug development. However, making the appropriate cells via induced pluripotent stem cells (iPSCs) requires reprogramming of somatic cells and subsequent redifferentiation. Given how arduous and lengthy this process can be, we sought to determine whether it might be possible to convert somatic cells into lineage-specific stem/progenitor cells of another germ layer in one step, bypassing the intermediate pluripotent stage. Here we show that transient induction of the four reprogramming factors (Oct4, Sox2, Klf4, and c-Myc) can efficiently transdifferentiate fibroblasts into functional neural stem/progenitor cells (NPCs) with appropriate signaling inputs. Compared with induced neurons (or iN cells, which are directly converted from fibroblasts), transdifferentiated NPCs have the distinct advantage of being expandable in vitro and retaining the ability to give rise to multiple neuronal subtypes and glial cells. Our results provide a unique paradigm for iPSC-factor-based reprogramming by demonstrating that it can be readily modified to serve as a general platform for transdifferentiation.  相似文献   
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Previously conducted studies revealed that smoking enhanced the efficacy of clopidogrel by increasing formation of the active metabolite (AM) from the prodrug through induction of the cytochrome CYP1A2. The expression of cytochrome enzymes depends on genotype and no data exists in literature conducted in Turkish patients comparing the clopidogrel responsiveness between active smokers and non-active smokers treated with clopidogrel. In this study, our aim was to investigate the clopidogrel responsiveness in clopidogrel-treated Turkish acute coronary syndrome (ACS) patients according to their smoking status. We retrospectively enrolled 258 patients who were hospitalized due to ACS. Clinical variables of the patients, especially smoking status were recorded. Clopidogrel resistance was evaluated by using adenosine diphosphate (ADP) induced platelet aggregometry. Clopidogrel resistance was detected as a change in maximal aggregation ≤20% from baseline. A total of 139 patients were active smokers while 12 were former smokers. 107 patients did not have a history of smoking. Ten of the smokers were hyporesponsive to clopidogrel, whereas 36 of non-smokers were hyporesponsive to clopidogrel (p?612.5 predicted the clopidogrel resistance with a sensitivity of 60% (OR: 100.65, %95 CI?=?19.996–506.615 p?相似文献   
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