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1.
OBJECTIVE: The aim of this study was to measure leakage of 4 resin-based sealers. STUDY DESIGN: Four groups of premolars (n = 60) were prepared using GT Rotary files and the crown-down technique and filled by the single-cone technique with AH26, AHPlus, EndoREZ, and an experimental MBP as sealer. Leakage was measured using the fluid filtration method after 15, 30, and 60 days and determined as microL/min(-1) x 10 psi. RESULTS: Statistical analysis by ANOVA and Tukey HSD test indicated that root fillings with AH Plus and the MBP showed lower leakage values after 15 days (P < .05). At 30 days, AH26 presented higher leakage values when compared to other sealers (P < .05). At 60 days, MBP and AH Plus presented the lower leakage values, differing significantly from EndoREZ (P < .05). CONCLUSION: It was observed that AH Plus and the experimental MBP showed lower leakage after 60 days than AH 26 and EndoREZ.  相似文献   
2.
We investigated the association between pulse wave velocity (PWV) and HIV infection, antiretroviral treatment-related characteristics, viral load, immune status, and metabolic changes in a cross-sectional study nested in a cohort of HIV/AIDS patients who have been followed for metabolic and cardiovascular changes since 2007. The study included patients recruited from the cohort (N = 261) and a comparison group (N = 82) of uninfected individuals, all enrolled from April to November 2009. Aortic stiffness was estimated using the carotid-femoral PWV (Complior-Artech, Paris, France). The groups were similar with respect to age, metabolic syndrome, diabetes mellitus, Framingham score, and use of antihypertensive and hypolipidemic medications. Hypertension was more frequent among the controls. Individuals with HIV had higher triglyceride, glucose and HDL cholesterol levels. Among individuals with HIV/AIDS, those with a nadir CD4+ T-cell count <200 cells/mm3 had a higher PWV (P = 0.01). There was no statistically significant difference when subjects were stratified by gender. Heart rate, age, male gender, and blood pressure were independently correlated with PWV. Nadir CD4+ T-cell count did not remain in the final model. There was no significance difference in PWV between HIV-infected individuals and uninfected controls. PWV was correlated with age, gender, and blood pressure across the entire population and among those infected with HIV. We recommend cohort studies to further explore the association between inflammation related to HIV infection and/or immune reconstitution and antiretroviral use and PWV.  相似文献   
3.

Objective  

To evaluate the effectiveness and safety of polyunsaturated fatty acids for the treatment of the premenstrual syndrome (PMS) using a graded symptom scale and to assess the effect of this treatment on basal plasma levels of prolactin and total cholesterol.  相似文献   
4.
The Brazilian Consensus on Gastroesophageal Reflux Disease considers gastroesophageal reflux disease to be a chronic disorder related to the retrograde flow of gastroduodenal contents into the esophagus and/or adjacent organs, resulting in a variable spectrum of symptoms, with or without tissue damage. Considering the limitations of classifications currently in use, a new classification is proposed that combines three criteria-clinical, endoscopic, and pH-metric-providing a comprehensive and more complete characterization of the disease. The diagnosis begins with the presence of heartburn, acid regurgitation, and alarm manifestations (dysphagia, odynophagia, weight loss, GI bleeding, nausea and/or vomiting, and family history of cancer). Also, atypical esophageal, pulmonary, otorhinolaryngological, and oral symptoms may occur. Endoscopy is the first approach, particularly in patients over 40 yr of age and in those with alarm symptoms. Other exams are considered in particular cases, such as contrast radiological examination, scyntigraphy, manometry, and prolonged pH measurement. The clinical treatment encompasses behavioral modifications in lifestyle and pharmacological measures. Proton pump inhibitors in manufacturers' recommended doses are indicated, with doubling of the dose in more severe cases of esophagitis. The minimum time of administration is 6 wk. Patients who do not respond to medical treatment, including those with atypical manifestations, should be considered for surgical treatment. Of the complications of gastroesophageal reflux disease, Barrett's esophagus presents a potential development of adenocarcinoma; biopsies should be performed, independent of Barrett's esophagus extent or location. In this regard the designation "short Barrett's" is not important in terms of management and prognosis.  相似文献   
5.
Four genetic polymorphisms located at the promoter (C-257T) and coding regions of CFH gene (exon 2 G257A, exon 14 A2089G and exon 19 G2881T) were investigated in 121 dengue patients (DENV-3) in order to assess the relationship between allele/haplotypes variants and clinical outcomes. A statistical value was found between the CFH-257T allele (TT/TC genotypes) and reduced susceptibility to severe dengue (SD). Statistical associations indicate that individuals bearing a T allele presented significantly higher protein levels in plasma. The −257T variant is located within a NF-κB binding site, suggesting that this variant might have effect on the ability of the CFH gene to respond to signals via the NF-κB pathway. The G257A allelic variant showed significant protection against severe dengue. When CFH haplotypes effect was considered, the ancestral CG/CG promoter-exon 2 SNP genotype showed significant risk to SD either in a general comparison (ancestral × all variant genotypes), as well as in individual genotypes comparison (ancestral × each variant genotype), where the most prevalent effect was observed in the CG/CG × CA/TG comparison. These findings support the involvement of −257T, 257A allele variants and haplotypes on severe dengue phenotype protection, related with high basal CFH expression.  相似文献   
6.
Clinical Oral Investigations - To evaluate ex vivo the efficacy of the integrated motor Tri Auto ZX2 in controlling the apical extent of preparation compared to conventional visual control (CVC) of...  相似文献   
7.

Introduction

Left atrioventricular valve regurgitation is the most concerning residual lesion after surgical correction of atrioventricular septal defect.

Objective

To determine factors associated with moderate or greater left atrioventricular valve regurgitation within 30 days of surgical repair of incomplete atrioventricular septal defect.

Methods

We assessed the results of 51 consecutive patients 14 years-old and younger presenting with incomplete atrioventricular septal defect that were operated on at our practice between 2002 and 2010. The following variables were considered: age, weight, absence of Down syndrome, grade of preoperative left atrioventricular valve regurgitation, abnormalities on the left atrioventricular valve and the use of annuloplasty. The median age was 4.1 years; the median weight was 13.4 Kg; 37.2% had Down syndrome. At the time of preoperative evaluation, there were 23 cases with moderate or greater left atrioventricular valve regurgitation (45.1%). Abnormalities on the left atrioventricular valve were found in 17.6%; annuloplasty was performed in 21.6%.

Results

At the time of postoperative evaluation, there were 12 cases with moderate or greater left atrioventricular valve regurgitation (23.5%). The variation between pre- and postoperative grades of left atrioventricular valve regurgitation of patients with atrioventricular valve malformation did not reach significance (P=0.26), unlike patients without such abnormalities (P=0.016). During univariate analysis, only absence of Down syndrome was statistically significant (P=0.02). However, after a multivariate analysis, none of the factors reached significance.

Conclusion

None of the factors studied was determinant of a moderate or greater left atrioventricular valve regurgitation within the first 30 days of repair of incomplete atrioventricular septal defect in the sample. Patients without abnormalities on the left atrioventricular valve benefit more of the operation.  相似文献   
8.
Juvenile ossifying fibroma (JOF) is a rare fibro-osseous neoplasm, defined as a variant of the ossifying fibroma that arises within the craniofacial bones. Two subgroups, juvenile psammomatoid ossifying fibroma (PsJOF) and juvenile trabecular ossifying fibroma, have been delineated by their histology. PsJOF occurs predominantly in the sinonasal and orbital bones. This work reports on 2 cases of extensive PsJOF in the body of the right mandible as well as reviews the literature regarding the radiographic and histologic features, treatment, and prognosis of PsJOF of the jaws.  相似文献   
9.
The polysialylated form of the neuronal cell adhesion molecule (PSA‐NCAM) is expressed by immature neurons in the amygdala of adult mammals, including non‐human primates. In a recent report we have also described the presence of PSA‐NCAM‐expressing cells in the amygdala of adult humans. Although many of these cells have been classified as mature interneurons, some of them lacked mature neuronal markers, suggesting the presence of immature neurons. We have studied, using immunohistochemistry, the existence and distribution of these immature neurons using post mortem material. We have also analysed the presence of proliferating cells and the association between immature neurons and specialised astrocytes. These parameters have also been studied for comparative purposes in the amygdalae of cats and squirrel monkeys. Our results demonstrate that cells coexpressing doublecortin and PSA‐NCAM, but lacking neuronal nuclear antigen expression, were present in the amygdala of adult humans. These cells were organised in elongated clusters, which were located between the white matter of the dorsal hippocampus and the basolateral amygdaloid nucleus. These clusters were not associated with astroglial specialised structures. No cells expressing the proliferative marker Ki67 were observed in the amygdaloid parenchyma, although some of them were found in the vicinity of the lateral ventricle. Immature neurons were also present in the amygdala of squirrel monkeys and cats. These cells also appeared clustered in monkeys, although not as organised as in humans. In cats these cells are scarce, appear isolated and most of the PSA‐NCAM‐expressing structures corresponded to processes apparently originating from the paleocortical layer II.  相似文献   
10.

Objective

To evaluate the height and weight development of children with congenital heart disease undergoing surgery with the goal of determining when they reach the threshold of normal development and whether there are differences between patients with developmental pattern below the level of normality preoperatively (z-score<-2 for the analyzed parameter) in comparison to the total group of cardiac patients.

Methods

We prospectively followed up 27 children undergoing operation into five time periods: preoperatively and at four subsequent outpatient appointments: 1st month, 3rd month, 6th month and 12th month after hospital discharge. The anthropometric parameters used were median z-score (MZ), weight (WAZ), height (HAZ), subscapular skinfold (SSFAZ), upper arm circumference (UAC) and triceps skinfold (TSFAZ). The evolution assessment of the parameters was performed by analysis of variance and comparison with the general normal population from unpaired t test, both in the total group of cardiac patients, and in subgroups with preoperative parameters below the normal level (Zm<-2).

Results

In the total group there was no significant evolution of MZ of all parameters. WAZ was statistically lower than the normal population until the 1st month of follow-up (P=0.028); HAZ only preoperatively (P=0.044), SSFAZ in the first month (P=0.015) and at 12th month (P=0.038), UAC and TSFAZ were always statistically equal to the general population. In patients whose development was below the level of normality, there were important variation of WAZ (P=0.002), HAZ (P=0.001) and UAC (P=0.031) after the operation, and the WAZ was lower than the normal population until the 3rd month (P=0.015); HAZ and UAC, until the first month (P=0.024 and P=0.039 respectively), SSFAZ, up to the 12th month (P=0.005), the TSFAZ only preoperatively (P=0.011).

Conclusion

The operation promoted the return to normalcy for those with heart disease in general within up to three months, but for the group of patients below normal developmental pattern of the return occurred within 12 months.  相似文献   
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