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81.

Objective

This in vitro study evaluated the influence of two 10% carbamide peroxide bleaching agents - a commercial product (Opalescence PF; Ultradent Products, Inc.) and a bleaching agent prepared in a compounding pharmacy - on the chemical degradation of a light-activated composite resin by determining its release of ions before and after exposure to the agents.

Material and Methods

Thirty composite resin (Filtek Z250; 3M/ESPE) samples were divided into three groups: group I (exposed to Opalescence PF commercial bleaching agent), group II (exposed to a compounded bleaching agent) and group III (control - Milli-Q water). After 14 days of exposure, with a protocol of 8 h of daily exposure to the bleaching agents and 16 h of immersion in Milli-Q water, the analysis of ion release was carried out using a HP 8453 spectrophotometer. The values were analyzed statistically by ANOVA, Tukey''s test and the paired t-tests. The significance level was set at 5%.

Results

After 14 days of the experiment, statistically significant difference was found between group II and groups I and III, with greater ion release from the composite resin in group II.

Conclusions

The compounded bleaching agent had a more aggressive effect on the composite resin after 14 days of exposure than the commercial product and the control (no bleaching).  相似文献   
82.
BACKGROUND: To compare retinal thickness and subretinal hyper-reflectivity using Stratus optical coherence tomography (OCT3) between the eyes of patients with bilateral end-stage exudative age-related macular degeneration (AMD), where one eye has been treated with photodynamic therapy (PDT). METHODS: Patients with PDT-treated stable choroidal neovascularization (CNV), defined as a fibrotic lesion not requiring treatment for 6 months, in one eye and an untreated end-stage CNV (disciform) scar in their fellow eye, underwent refraction protocol logMAR visual acuity (VA) in letters, slit-lamp biomicroscopy, fluorescein angiography and OCT3 scan. Subretinal scar thickness was measured as Outer High Reflectivity Band Thickness (OHRBT) and retinal thickness as neuroretinal foveal thickness (NFT) on OCT3. RESULTS: Thirty-two eyes of 16 patients were studied. Mean OHRBT was 255.62 microm in treated eyes and 350.8 microm in untreated eyes (P = 0.001). Mean NFT was 130.3 microm in the treated eye and 79.9 microm in the untreated eye (P = 0.017). Mean VA was 42 letters in treated eyes and 15 letters in untreated eyes (P < 0.005). CONCLUSION: Based on OCT3 findings, eyes with AMD treated with PDT have a thinner fibrous scar and better preserved retinal thickness when compared with untreated fellow eyes with end-stage fibrotic scarring.  相似文献   
83.
84.
The Kir4.1 gene (KCNJ10) encodes an inwardly rectifying K(+) channel subunit abundantly expressed in the CNS. Its expression in the mammalian inner ear has been suggested but its function in vivo in the inner ear is unknown. Because diverse human hereditary deafness syndromes are associated with mutations in K(+) channels, we examined auditory function and inner ear structure in mice with a genetically inactivated Kir4.1 K(+) channel subunit. Startle response experiments suggest that Kir4.1-/- mice are profoundly deaf, whereas Kir4.1+/- mice react like wild-type mice to acoustic stimuli. In Kir4.1-/- mice, the Reissner membrane is collapsed, the tectorial membrane is swollen, and type I hair cells and spiral ganglion neurons as well as their central processes degenerate over the first postnatal weeks. In the vestibular ganglia, neuronal cell death with apoptotic features is also observed. Immunostaining reveals that Kir4.1 is strongly expressed in stria vascularis of wild-type but not Kir4.1-/- mice. Within the spiral ganglion, Kir4.1 labeling was detected on satellite cells surrounding spiral ganglion neurons and axons. We conclude that Kir4.1 is crucial for normal development of the cochlea and hearing, via two distinct aspects of extracellular K(+) homeostasis: (1). in stria vascularis, Kir4.1 helps to generate the cochlear endolymph; and (2). in spiral and vestibular ganglia, Kir4.1 in surrounding glial cells helps to support the spiral and vestibular ganglion neurons and their projecting axons.  相似文献   
85.
Background Self‐reporting is widely used in medical research. The objective of the present study was to evaluate the specificity and sensitivity of self‐reported lesions of acne (scars and active lesions) obtained by an interview with the examination carried out by a dermatologist. Methods A questionnaire was applied to male adolescents who registered for obligatory military service. After that, skin examination was carried out. Results Of the 2,191 adolescents examined, 474 (21.60%) showed acne scars, and 625 (28.51%) admitted to having scars. The sensitivity of self‐reported scars was 50.84%, and the specificity was 77.65%. The prevalence of active acne obtained by the dermatological examination was 85.76% and from self‐reported acne was 76.12%, with a sensitivity of 80.95% and a specificity of 52.88%. Neither schooling nor social class made any difference to sensitivity or specificity. Conclusions Our findings showed that sensitivity and specificity of self‐reported acne was very low, pointing out that, in a sample of adolescents, self‐reporting of acne shows itself as an inadequate instrument for epidemiological studies.  相似文献   
86.

BACKGROUND

It has been demonstrated that neutrophils, eosinophils and monocytes, under appropriated stimulus, may express tissue factor and therefore, activate the extrinsic pathway of coagulation. We performed a transversal and case-control study of patients with chronic urticaria and patients with psoriasis, in our outpatient clinic to evaluate the production of D-dimer.

OBJECTIVE

To evaluate D-dimer serum levels in patients with chronic urticaria and its possible correlation with disease activity.

PATIENTS AND METHODS

The study was conducted from October 2010 until March 2011. We selected 37 consecutive patients from our Allergy Unit and Psoriasis Unit, and divided them into three groups for statistical analysis: (i) 12 patients with active chronic urticaria (CU); (ii) 10 patients with chronic urticaria under remission and (iii) 15 patients with psoriasis (a disease with skin inflammatory infiltrate constituted by neutrophils, lymphocytes and monocytes). Another five patients with urticarial vasculitis were allocated in our study, but not included in statistical analysis. The serum levels of D-dimer were measured by Enzyme Linked Fluorescent Assay (ELFA), and the result units were given in ng/ml FEU.

RESULTS

Patients with active chronic urticaria had the highest serum levels of D-dimer (p<0.01), when compared to patients with CU under remission and the control group (patients with psoriasis).

CONCLUSIONS

Patients with active chronic urticaria have higher serum levels of D-dimer, when compared to patients with chronic urticaria under remission and patients with psoriasis. We found elevated serum levels of D-dimer among patients with urticarial vasculitis.  相似文献   
87.
PURPOSE: To evaluate corneal changes and ocular aberrations during an orthokeratology test. DESIGN: A prospective, nonrandomized cohort study. METHODS: Fourteen myopic patients (26 eyes) underwent an orthokeratology fitting test with the BE contact lens (Ultravision Pty, Ltd, Brisbane, Australia). Best spectacle-corrected visual acuity (BSCVA), uncorrected (Ultravision Pty, Ltd, Brisbane, Australia) visual acuity (UCVA), subjective cycloplegic refraction, biomicroscopy, corneal topography, optical pachymetry, and aberrometry were performed at baseline and one and eight nights orthokeratology. The short-term effect of orthokeratology using corneal topography, tomography, and ocular aberrations was evaluated. RESULTS: The mean spherical equivalent changed from -2.24 +/- 0.98 diopters (D) at baseline to 0.15 +/- 0.76 D after the eight nights of lens wear (P = .001). All patients had an UCVA of 20/30, 69.2% with 20/20. Changes in central corneal pachymetry were not observed. There was a statistically significant increase in the temporal corneal thickness from night one, without any difference between nights one and eight (P > .001). A significant increase of higher-order root mean square values was observed from baseline (0.42 +/- 0.16 mum), night one (0.81 +/- 0.24 mum), and night eight (1.04 +/- 0.24 mum). Increases in coma (Z7+Z8) and spherical aberration (Z12) were observed. Positive horizontal (Z8) coma increased in right eyes, and negative horizontal (Z8) coma increased in left eyes (P < .001). CONCLUSIONS: Myopia reduction resulting from rapid central corneal flattening and improvement of UCVA occurred after orthokeratology. Higher-order aberrations (HOAs), particularly spherical aberration and coma, increased significantly during the orthokeratology test. An increase of temporal pachymetry and differences in coma direction induced between the eyes may be related to the subclinical lens decentration temporally.  相似文献   
88.
Cutaneous leishmaniasis represents a public health problem that affects 85 countries. It is an endemic disease in Brazil, having an important socioeconomic impact. An exuberant case of cutaneous leishmaniasis is reported herein. A 28-year-old male patient with Down syndrome had had verrucous plaques on the back for over a year, with progressive growth. PCR of a lesion sample was positive for Leishmania braziliensis. The patient's condition was classified as atypical cutaneous leishmaniasis. He was successfully treated with amphotericin B and miltefosine. The treatment remains a challenge, given the toxicity and low cure rate of the currently recommended drugs.  相似文献   
89.
Objective: To evaluate the influence of the local prenatal surveillance of twin pregnancies in the obstetrical results.

Methods: A prospective cohort study of multiple pregnancies delivered over a period of 16 years in a tertiary centre was conducted. In this study 861 twin pregnancies were included. They were compared for obstetric complications, gestational age at delivery, mode of delivery and birthweight, according to the place of the surveillance.

Results: Of the 861 cases examined, the following obstetric complications were significantly different: metrorrhagia (p?=?0.039), infections (p?p?=?0.007), PROMPT (p?p?=?0.024). The mode of delivery was similar but occurred mostly ≤32 weeks (p?p?Conclusion: Our results demonstrate the crucial importance of prenatal surveillance be carried in a differentiated referral centers with specific/strict protocols or the urgent implementation of same protocols in all other places of surveillance, since this straight surveillance greatly reduces the occurrence of prenatal complications, mainly PROMPT, PTD.  相似文献   
90.
Opportunistic infections in endogenous Cushing's syndrome are associated with severe cortisol excess and carry a high mortality. Pulmonary cryptococcosis is one of these opportunistic infections and can mimic a lung neoplasm, therefore making its diagnosis difficult. We report a case of a young male with ACTH-dependent Cushing's syndrome and severe hypercortisolism. The patient achieved cure after the transfenoidal surgery, but developed a febrile state. A chest computed tomography showed a pulmonary nodule that did not change in serial chest radiographs. Diagnosis of tuberculosis, fungal and bacterial infections were inconclusive, so the hypothesis of lung neoplasm became more probable. The necropsy, however, disclosed a pseudotumoral cryptococcosis. Opportunistic infections, like Cryptococcus neoformans, should be considered in patients with Cushing's syndrome and a pulmonary infiltrate.  相似文献   
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