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The aim of this study was to evaluate in vitro the antimicrobial activity of glass ionomer (GIC) and zinc oxide-eugenol (ZOE) cements against Candida albicans. Standardized GIC and ZOE specimens were maintained in contact with C. albicans suspension (1 x 10(6) cells/ml) at 37 degrees C for 24 h, 48 h or 7 days. A control group without any testing cement was included. After the incubation period, aliquots of 0.1 ml were plated on Sabouraud's agar, and then the number of colonies was counted. The results were expressed as values of logarithms of colony-forming units per milliliter (log CFU/mL) and were analyzed statistically by Kruskal-Wallis ANOVA. After 48 h of incubation, the ZOE group presented no growth of C. albicans. GIC and control groups presented similar mean values at all tested periods. According to the results obtained, it could be concluded that, under the experimental conditions, ZOE cement was more effective in vitro against C. albicans than GIC.  相似文献   
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BACKGROUND: Aluminum oxide crystal microdermabrasion has recently become popular for facial rejuvenation. Although it is a widely used technique with perceptible benefits, the clinical efficacy on photodamaged skin has yet to be established. OBJECTIVE: To measure and quantify the effect of microdermabrasion on photodamaged skin. METHODS: Ten subjects underwent one treatment a week for five to six treatments. Skin surface roughness, topography, elasticity, stiffness, compliance, temperature, sebum content, and histology were analyzed. RESULTS: Subjectively, seven patients noticed a mild improvement. Physician analysis of clinical photography indicated mild improvement in the majority of patients. Objectively, immediately following treatment skin temperature increased, sebum content decreased, and a temporary increase in skin roughness and mild flattening of some wrinkles occurred. Dynamic skin analysis demonstrated a perceptible decrease in skin stiffness and an increase in skin compliance. Histology showed slight orthokeratosis and flattening of rete ridges and a perivascular mononuclear cell infiltrate, edema, and vascular ectasia in the upper reticular dermis 1 week after completion of the series of treatments. CONCLUSION: Immediately following the procedure, changes occurring in skin characteristics can be measured that are consistent with mild abrasion and increased blood flow. Objective biomechanical analysis demonstrated a statistically significant decrease in skin stiffness and an increase in skin compliance consistent with persistent edema. Subjectively, patients and physicians report a mild improvement in the majority of subjects. Histology showed dramatic vascular changes in the reticular dermis below the level of direct abrasion. The effect of negative pressure may result in these vascular changes.  相似文献   
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Suppression of tinnitus by electrical stimulation via a cochlear implant has been studied in recent years. Some individuals who undergo cochlear implant surgery report total or partial relief of the symptoms even in the contralateral ear. The mechanisms involved in this suppression are not clear. The results obtained in our study demonstrated an improvement of 71% in 29 implant cases, confirming data found in the literature. Our aim was to study tinnitus in individuals before surgery and after cochlear implant activation and to observe improvement in the perception of tinnitus, comparing these results with data in the literature. We conducted a retrospective study of 29 postlingual adults who had profound sensorineural hearing loss and underwent cochlear implant surgery at the cochlear implant sector of the Otorhinolaryngology, Head and Neck Surgery Department, University of Campinas, S?o Paulo, Brazil, between May 2003 and June 2005. The device employed in this procedure was the Nucleus 24K multichannel device (Cochlear Ltd, Lane Cove, Australia). After the internal component was activated, patients completed a questionnaire. Before surgery, 21 of the 29 patients (72%) who later underwent cochlear implant surgery presented with tinnitus, which was bilateral in 14 cases (67%). After the cochlear implant was activated, seven patients (33%) presented with total suppression, and eight patients (39%) reported partial relief. In the 14 cases with bilateral symptoms, tinnitus was totally suppressed or decreased in both ears in 12 cases (86%). Individuals who underwent multichannel cochlear implant surgery presented with reduced tinnitus even in the contralateral ear.  相似文献   
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Background

The Amplatzer septal occluder (ASO) allows the percutaneous closure of small to very large atrial septal defects (ASDs). The CardioSEAL/STARflex (CS/SF) can be used only for closure of small to moderate ASDs (stretch size up to 18 mm). These 2 devices are widely used in clinical practice. Therefore, a comparison of their use in the closure of small to moderate ASDs is needed.

Methods

From December 1996 to September 2002, 274 consecutive patients (mean age 20.3 ± 17 years) underwent percutaneous closure of small to moderate ostium secundum ASDs. The CS/SF device was used in 121 patients, and the ASO was used in 153.

Results

There were no differences in age, sex ratio, or pulmonary/systemic flow ratio. Stretch size of the defect was higher in the ASO group (13.6 ± 3.5 mm vs 15.5 ± 3.2 mm, P < .001). Procedure time and fluoroscopy time were shorter in patients treated with the ASO (61 ± 21 vs 75 ± 32 min, P < .0003, and 11.6 ± 9 vs 23.8 ± 17.4 min, P < .0001, respectively). Residual shunt at procedure and discharge was significantly more frequent in the CS/SF group (P < .0001). There were no differences in the complication rate for the 2 groups (CS/SF 4/121 vs ASO 6/153). Length of follow-up was longer in the CS/SF group (24 ± 14 vs 16 ± 9 months, P = .0001). Residual shunting was significantly more frequent in the CS/SF group during follow-up, while closure rate reached 100% after 1 month in ASO group.

Conclusions

The 2 devices are clinically safe and effective in ASD closure. However, percutaneous closure of small to moderate ASDs with ASO is quicker and provides an higher rate of complete occlusion.  相似文献   
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Sleep and Breathing - There are no studies comparing tests performed at home with those carried out in the laboratory, using the same device. The&nbsp;only studies that have been performed...  相似文献   
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