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1.
Five-year clinical performance of porcelain laminate veneers.   总被引:2,自引:0,他引:2  
OBJECTIVE: The clinical performance of porcelain laminate veneers was evaluated at 5 years. METHOD AND MATERIALS: One hundred eighty-six porcelain laminate veneers were placed in 61 patients, aged 18 to 70 years, by a single operator following the same clinical procedure. At the 5-year recall, esthetics, marginal integrity, marginal discoloration, fracture rate, and patient satisfaction were recorded. RESULTS: At recall 98.4% of the veneers were satisfactory without intervention. The retention rate was excellent, the fracture rate was very low, and the maintenance of esthetics was superior. Patient satisfaction was very high. CONCLUSION: Porcelain laminate veneers offer a reliable and effective procedure for the conservative and esthetic treatment of anterior teeth.  相似文献   
2.
Activation of the peroxisome proliferator-activator receptor gamma (PPARgamma) improves insulin resistance and glycemic control in patients with diabetes. As PPARgamma is expressed in the endothelial cell, we have investigated the effect of troglitazone, a PPARgamma activator, on the endothelial function in people with type 2 diabetes in a 12-week, prospective, randomized, double-blinded clinical trial. We studied 87 type 2 diabetic patients who were divided into 3 groups. Group A consisted of 27 patients with recently diagnosed diabetes and no clinical manifestations of macrovascular disease; group B, 29 patients with long-term diabetes and no clinically evident macrovascular disease; and group C, 31 diabetic patients with documented macrovascular disease (cardiovascular, cerebrovascular, or peripheral vascular disease). High-resolution ultrasound images were used to measure the flow-mediated dilation (FMD, endothelium-dependent) and nitroglycerin-induced dilation (NID, endothelium-independent) in the brachial artery. Laser Doppler perfusion imaging was used to measure vasodilation in the forearm skin in response to iontophoresis of 1% acetylcholine (Ach, endothelium-dependent) and 1% sodium nitroprusside (NaNP, endothelium-independent). The plasma concentrations of von Willebrand factor (vWF), soluble intercellular adhesion molecule (sICAM), and soluble vascular cell adhesion molecule (sVCAM) were also measured as indicators of endothelial cell activation. The FMD improved in the troglitazone-treated patients in group A (7.72 +/- 3.4 v 5.27 +/- 2.0, P <.05 [exit visit v baseline, percent of increase in brachial artery diameter, mean +/- SD]). The fasting insulin level also improved in this group (15.6 +/- 10 v 19.7 +/- 10, P <.05) and was strongly correlated to changes in FMD (r = -.73, P <.01). No changes were found in the FMD or the fasting insulin levels in the troglitazone-treated patients in groups B or C. The NID was not changed by troglitazone treatment in any of the 3 groups. Also, no differences were found in the microcirculation reactivity measurements or in the biochemical markers of endothelial dysfunction in all 3 groups. A small, but significant, improvement of the FMD was found in placebo-treated patients in group B, probably related to the low FMD levels at baseline in the patients (5.40 +/- 3.0 v 4.36 +/- 2.4, P <.05). We concluded that troglitazone treatment for 12 weeks improved endothelial function in the macrocirculation of patients with recently diagnosed type 2 diabetes and no clinical evidence of macrovascular disease. This improvement was strongly associated with the improvement of fasting plasma insulin concentrations.  相似文献   
3.
The two main objectives of this study were: (1) to examine the effect of aspirin on the endothelial function in healthy subjects and (2) to examine the effect of deionized water and 5% NaCl as iontophoresis solution vehicles. The skin microcirculation was evaluated at the forearm level of healthy subjects. A laser Doppler scanner was employed to measure vasodilation in response to the iontophoresis of 1% acetylcholine (endothelium-dependent) and 1% sodium nitroprusside (endothelium-independent). In the first experiment, nine healthy subjects were given 500 mg aspirin daily for 3 days. The microvascular reactivity was measured at the beginning and the end of the study. In the second experiment, the response to iontophoresis of acetylcholine and sodium nitroprusside as 1% solutions of deionized water was compared to the responses that were achieved after the iontophoresis of deionized water or 5% NaCl solution. After 3 days of aspirin intake, there were no changes in the vasodilatory response to acetylcholine (endothelium-dependent vasodilation) [81 +/- 11 vs 77 +/- 10 (% of increase over baseline at the beginning vs the end of the study, mean +/- SE), P = NS] or sodium nitroprusside (endothelium-independent vasodilation) (69 +/- 8 vs 64 +/- 12, P = NS). There was also a negligible response after the iontophoresis of 5% NaCl (3 +/- 4) and deionized water (6 +/- 4) in anodal mode (the mode employed for the iontophoresis of acetylcholine). In cathodal mode, employed for the iontophoresis of sodium nitroprusside, the response to 5% NaCl was still negligible but a considerable response was found after the iontophoresis of deionized water. In normal healthy subjects, aspirin administration has no effect on forearm skin microvascular reactivity, including both endothelium-dependent and endothelium-independent vasodilation. In addition, a NaCl solution would be preferable to deionized water as the iontophoresis solution vehicle.  相似文献   
4.
OBJECTIVE: To evaluate the vasodilation induced by topical application of methyl nicotinate (MN) and to compare it with the vasodilatory response to acetylcholine (ACh) and sodium nitroprusside (SNP) in healthy subjects and diabetic neuropathic patients. RESEARCH DESIGN AND METHODS: Ten diabetic patients with peripheral neuropathy (DN) and 10 age- and sex-matched healthy control subjects (C) were enrolled. The vasodilatory response to topical application of 1% MN and a placebo emulsion at the forearm and dorsum of the foot skin at 5, 15, 30, 60 and 120 min was measured using Laser Doppler Perfusion Imaging. The vasodilatory response to iontophoresis of 1% ACh and 1% SNP solutions was also evaluated. RESULTS: The maximal vasodilatory response to ACh, SNP and MN was similar at the forearm and foot level in the diabetic patients. In the control group, the responses to MN, ACh and SNP were similar on the forearm but in the foot, the MN vasodilatory response was higher when compared to the ACh and SNP responses. MN-related vasodilation was present 5 min after the application, reached its peak at 15-30 min and declined to pre-application levels 120 min afterward. CONCLUSIONS: Topical application of MN at the forearm and foot levels of diabetic neuropathic patients results in skin vasodilation that is comparable to the maximal vasodilation that can be induced by iontophoresis of ACh or SNP and lasts for less than 2 h. Further studies will be required to explore the potential of MN to increase blood flow and to prevent diabetic foot problems in clinical practice.  相似文献   
5.
Objectives

To compare the efficacy, acceptance and preference of conventional infiltration technique with a needleless jet anaesthetic device (Comfort-In).

Materials and methods

Non-fearful healthy adult volunteers, aged 19–40 years, were recruited in the Dental School of Aristotle University of Thessaloniki, Greece. Intact maxillary premolars were selected for local anaesthesia. Both techniques were applied sequentially with 35 min time gap on either buccal side on the same day by the same operator. The quadrant and the order of administration were randomly assigned using an online randomization generator. Immediately after administration, at 1, 3, 5, 10, 15, 20, 25 and 30 min, pulp vitality and soft tissue pain reaction tests were performed. Each participant was asked 6 questions in order to assess acceptance. At the end of the session, at 24 h and 7 days, all participants were asked to report any adverse events and their preference.

Results

In 63 volunteers who were successfully followed, 63 teeth received conventional local infiltration and 63 the Comfort-In. Both techniques presented with similar anaesthetic efficacy at 1, 3, 5, 10 and 15 min, whereas the conventional technique was more efficacious at 20 min (p < 0.005). Both presented similar acceptance apart from higher pain/discomfort during administration of Comfort-In (p = 0.002). Significantly higher preference was reported for the conventional technique immediately after the session, at 24 h and at 7 days (p < 0.0005); 19 (30.2%) reported the presence of ecchymosis or lacerations at the Comfort-In site as opposed to 5 (7.9%) with the conventional method (p < 0.0001).

Conclusion

Both techniques showed similar effectiveness. Conventional infiltration was preferred to needleless anaesthesia by non-fearful adult volunteers and was associated with less adverse events.

Clinical relevance

This study enhances the advantages of conventional local anaesthesia.

Trial registration

ISRCTN17400733

  相似文献   
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Cancer is driven by genetic mutations in oncogenes and tumor suppressor genes and by cellular events that develop a misregulated molecular microenvironment in the growing tumor tissue. The tumor microenvironment is guided by the excessive action of specific cytokines including transforming growth factor‐β (TGF‐β), which normally controls embryonic development and the homeostasis of young or adult tissues. As a consequence of the genetic alterations generating a given tumor, TGF‐β can preserve its homeostatic function and attempt to limit neoplastic expansion, whereas, once the tumor has progressed to an aggressive stage, TGF‐β can synergize with various oncogenic stimuli to facilitate tumor invasiveness and metastasis. TGF‐β signaling mechanisms via Smad proteins, various ubiquitin ligases, and protein kinases are relatively well understood. Such mechanisms regulate the expression of genes encoding proteins or non‐coding RNAs. Among non‐coding RNAs, much has been understood regarding the regulation and function of microRNAs, whereas the role of long non‐coding RNAs is still emerging. This article emphasizes TGF‐β signaling mechanisms leading to the regulation of non‐coding genes, the function of such non‐coding RNAs as regulators of TGF‐β signaling, and the contribution of these mechanisms in specific hallmarks of cancer.  相似文献   
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10.
The purpose of this study was to evaluate the effect of amantadine sulfate infusion on the N30 component of the median nerve short-latency somatosensory evoked potentials (SSEPs) in patients with Parkinson's disease (PD). Twenty patients with advanced PD and severe motor fluctuations received a 6-day course of amantadine sulfate infusion (400 mg/day) plus their usual levodopa medication. Patients were assessed clinically by means of the Unified Parkinson's Disease Rating Scale (UPDRS-III and -IV). SSEPs to median nerve stimulation were recorded from the parietal and frontal regions before and after the 6-day course of amantadine infusion. Mean UPDRS motor score during the ON and OFF phase improved after amantadine infusion, as did motor fluctuations. SSEP changes resulting from amantadine sulfate treatment were observed in the P20-N30 amplitude as follows: Mean P20-N30 amplitudes before and after treatment were 2.15 +/- 1.11 microV and 3.06 +/- 1.19 microV respectively (p = 0.000), whereas mean N30-P40 amplitude increased from 2.7 +/- 1.6 microV to 3.9 +/- 1.3 microV after treatment (p = 0.000). Our results indicate that coincident to its clinical impact, amantadine infusion in patients with PD affects electrophysiologic parameters as well.  相似文献   
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