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81.
Left ventricular noncompaction is an unusual but increasingly recognized cardiomyopathy, the etiology of which is still not definitely established. Clinical presentation includes a wide spectrum of scenarios, including heart failure, thromboembolism and malignant arrhythmias, with half of deaths occurring suddenly. Early detection of LVNC is therefore essential to prevent sudden cardiac death. To our knowledge, this is the first report of the presence of cardiac sympathetic nervous dysfunction, assessed by 123iodine-metaiodobenzylguanidine myocardial scintigraphy, in a patient with LVNC, preserved left ventricular systolic function and exercise-induced nonsustained ventricular tachycardia. This finding may be related to the increased arrhythmic risk observed in this cardiomyopathy, giving a new insight into the pathophysiology of LVNC.  相似文献   
82.
AIM: To investigate age, sex, histopathology and Helicobacter pylori (H. pylori) status, as risk factors for gastroduodenal disease outcome in Brazilian dyspeptic patients.tients submitted to upper gastroscopy at Hospital das Clinicas of Marilia, antral biopsy specimens were obtained and subjected to histopathology and H. pylori diagnosis. All patients presenting chronic gastritis (CG) and peptic ulcer (PU) disease localized in the stomach, gastric ulcer (GU) and/or duodenal ulcer (DU) were included in the study. Gastric biopsies (n = 668) positive for H. pylori by rapid urease test were investigated for vacuolating cytotoxin A (vacA ) medium (m) region mosaicism by polymerase chain reaction. Logistic regression analysis was performed to verify the association of age, sex, histopathologic alterations, H. pylori diagnosis and vacA m region mosaicism with the incidence of DU, GU and CG in patients. RESULTS: Of 1466 patients submitted to endoscopy, 1060 (72.3%) presented CG [male/female = 506/554; mean age (year) ± SD = 51.2 ± 17.81], 88 (6.0%) presented DU [male/female = 54/34; mean age (year) ± SD = 51.4 ± 17.14], and 75 (5.1%) presented GU [male/female = 54/21; mean age (year) ± SD = 51.3 ± 17.12] and were included in the comparative analysis. Sex and age showed no detectable effect on CG incidence (overall c 2 = 2.1, P = 0.3423). Sex [Odds ratios (OR) = 1.8631, P = 0.0058] but not age (OR = 0.9929, P = 0.2699) was associated with DU and both parameters had a highly significant effect on GU (overall c 2 = 30.5, P 0.0001). The histopathological results showed a significant contribution of ageing for both atrophy (OR = 1.0297, P 0.0001) and intestinal metaplasia (OR = 1.0520, P 0.0001). Presence of H. pylori was significantly associated with decreasing age (OR = 0.9827, P 0.0001) and with the incidence of DU (OR = 3.6077, P 0.0001). The prevalence of m1 in DU was statistically significant (OR = 2.3563, P = 0.0018) but not in CG (OR = 2.678, P = 0.0863) and GU (OR = 1.520, P = 0.2863). CONCLUSION: In our population, male gender was a risk factor for PU; ageing for GU, atrophy and metapla-sia; and H. pylori of vacA m1 genotype for DU.  相似文献   
83.
The aim of this study was to determine the effect of the oral environment on the corrosion of dental alloys with different compositions, using electrochemical methods. The corrosion rates were obtained from the current-potential curves and electrochemical impedance spectroscopy (EIS). The effect of artificial saliva on the corrosion of dental alloys was dependent on alloy composition. Dissolution of the ions occurred in all tested dental alloys and the results were strongly dependent on the general alloy composition. Regarding the alloys containing nickel, the Ni-Cr and Ni-Cr-Ti alloys released 0.62 mg/L of Ni on average, while the Co-Cr dental alloy released ions between 0.01 and 0.03 mg/L of Co and Cr, respectively.The open-circuit potential stabilized at a higher level with lower deviation (standard deviation: Ni-Cr-6Ti = 32 mV/SCE and Co-Cr = 54 mV/SCE). The potenciodynamic curves of the dental alloys showed that the Ni-based dental alloy with >70 wt% of Ni had a similar curve and the Co-Cr dental alloy showed a low current density and hence a high resistance to corrosion compared with the Ni-based dental alloys. Some changes in microstructure were observed and this fact influenced the corrosion behavior for the alloys. The lower corrosion resistance also led to greater release of nickel ions to the medium. The quantity of Co ions released from the Co-Cr-Mo alloy was relatively small in the solutions. In addition, the quantity of Cr ions released into the artificial saliva from the Co-Cr alloy was lower than Cr release from the Ni-based dental alloys.  相似文献   
84.

Introduction

Although impaired pulmonary function and respiratory sleep disorders are described as responsible for increased mortality in acromegalic patients, little is known about the tracheal abnormalities in this group of patients. Thus, the objectives of this study were to describe the tracheal structural abnormalities and correlate these changes with the respiratory function and clinical data of acromegalic patients.

Material and methods

This is a cross-sectional study that was carried out at two university hospitals. Twenty acromegalic patients underwent spirometry, forced oscillation technique, and computed tomography (CT) assessments. Dyspnea and daytime sleepiness were assessed using the Modified Medical Research Council (MMRC) scale and the Epworth Sleepiness Scale (ESS), respectively. Forty matched subjects served as controls.

Results

The acromegalic patients exhibited larger median ratios between forced expiratory flow and forced inspiratory flow at 50% of the forced vital capacity (FEF50%/FIF50%) (2.05 vs. 1.06, p = 0.0001) compared with healthy volunteers. In the CT analysis, acromegalic patients exhibited larger median differences between their cervical and thoracic tracheal diameters (Δ tracheal diameters) (3 vs. 1 mm; p = 0.003). An association was found between FEF50%/FIF50% and the following variables: mean resistance (Rm), cervical tracheal diameter, and Δ tracheal diameters. Rm also exhibited a negative correlation with cervical tracheal diameter. Neither the MMRC scale nor the ESS exhibited any significant correlation with large airway obstruction (LAO) indices or with the measured tracheal diameters.

Conclusions

Acromegalic patients have tracheal structural abnormalities which are associated with functional indicators of LAO but not with clinical data.  相似文献   
85.
Purpose: To evaluate the reproducibility of the Stroke Specific Quality of Life (SS-QOL) items that address the participation component of the International Classification of Functioning, Disability and Health (ICF) and analyse the correlation between the subscore of these 26 items and the total SS-QOL score.

Methods: Seventy-five stroke survivors participated in this study. Reproducibility was evaluated using the intraclass correlation coefficient (ICC2,1), standard error of measurement (SEM), minimum detectable change (MDC) and the Bland–Altman plot. The correlation between the subscore of the 26 items and the total SS-QOL score was analysed using Spearman’s correlation coefficients (rho) and simple linear regression. An alpha risk?≤?0.05 was considered for all analyses.

Results: The SS-QOL items that address the participation component of the ICF demonstrated excellent reliability (intra-rater ICC2,1?=?0.96; inter-rater ICC2,1?=?0.95). The SEM and MDC were adequate. The Bland–Altman plot demonstrated satisfactory agreement. A significant and strong correlation (rho?=?0.83) was found between the 26 SS-QOL items that address participation and the total SS-QOL score. Moreover, the evaluation of participation was found to explain 73% of the evaluation of health-related quality of life.

Conclusion: The 26 SS-QOL items that address the participation component of the ICF demonstrated adequate reproducibility. Thus, participation, which represents the social aspects of functionality, can be adequately evaluated with these items.
  • Implications for Rehabilitation
  • The 26 Stroke Specific Quality of Life items that address participation proved to be reproducible for the analysis of social participation following a stroke.

  • The findings can lead to a better understanding of the social participation of individuals with chronic hemiparesis and assist in the establishment of adequate treatment for such individuals.

  • The rehabilitation process can be directed towards more specific goals focused on the patient expectations, thereby contributing to greater humanization and effectiveness of treatment to improve social participation following a stroke.

  相似文献   
86.
There has been no systematic study of the immune response of individuals aged over 60 years living in Schistosomiasis mansoni-endemic areas, although senescence is reportedly associated with susceptibility to infection and progressive decline in immune function. We have shown previously, in two endemic areas in Minas Gerais, Brazil, that the frequency of individuals aged over 60 years with chronic schistosomiasis is no longer negligible. Moreover, several elderly individuals who have always lived in these endemic areas stay protected from infection. An important question for studies of ageing and disease control in developing countries is which differences in the immunological profile of these negatively tested (non-infected) individuals can account for their resistance to either infection or reinfection. We show, in the present study, that non-infected (negative) elderly individuals develop innate immune mechanisms of protection that replace the age-associated decline in T cell function. Non-infected elderly individuals from endemic areas of schistosome infection present an increase in the frequency of the natural killer (NK) CD56(low) subset of NK cells expressing Toll-like receptors (TLR)-1, -2, -3 and -4 as determined by flow cytometry analysis. In addition, the proportion of dendritic cells expressing TLR-1 is elevated as well as the frequency of monocytes expressing TLR-1 and -4. These results suggest that TLR expression by cells of the innate immune system may be related to the negative status of infection in some elderly individuals who are constantly exposed to S. mansoni. Developing mechanisms of protection from infection may represent a biomarker for healthy ageing in this population.  相似文献   
87.
Fungi are amongst the bioaerosols of most importance, as indicated by the growing interest in this field of research. The aim was to characterize the exposure to fungal burden in podiatry clinics using culture-based and molecular methods. Methods: Airborne fungi were collected using an impaction air sampler and surface samples were also performed. Fourteen air samples were collected for direct detection of fungal DNA from filamentous fungi and dermatophytes. Overall, 63.6 % of the evening samples and 46 % of the morning samples surpassed the threshold values (150 CFU/m3). Molecular detection, by real time PCR, of the target fungal species/strains (Aspergillus and Stachybotrys species) was negative for all samples collected. Trichophyton rubrum was detected by PCR analysis in one DNA sample collected on day six. Results suggest the use of both culture-based and molecular methodologies are desirable for a complete evaluation of fungal burden in this particular health care setting.  相似文献   
88.

Objective:

The purpose of this study was to compare the accuracy of two working cast fabrication techniques using strain- gauge analysis.

Methods:

Two working cast fabrication methods were evaluated. Based on a master model, 20 working casts were fabricated by means of an indirect impression technique using polyether after splinting the square transfer copings with acrylic resin. Specimens were assigned to 2 groups (n=10): Group A (GA): type IV dental stone was poured around the abutment analogs in the conventional way; Group B (GB), the dental stone was poured in two stages. Spacers were used over the abutment analogs (rubber tubes) and type IV dental stone was poured around the abutment analogs in the conventional way. After the stone had hardened completely, the spacers were removed and more stone was inserted in the spaces created. Six strain-gauges (Excel Ltd.), positioned in a cast bar, which was dimensionally accurate (perfect fit) to the master model, recorded the microstrains generated by each specimen. Data were analyzed statistically by the variance analysis (ANOVA) and Tukey''s test (α= 5%).

Results:

The microstrain values (με) were (mean±SD): GA: 263.7±109.07με, and GB: 193.73±78.83με.

Conclusion:

There was no statistical difference between the two methods studied.  相似文献   
89.
Regional odontodysplasia (RO), also known as ghost teeth, is an unusual nonhereditary developmental anomaly of tooth formation that characteristically affects enamel and dentin formation of the primary and/or permanent dentition. In the present paper, we report a case of RO affecting a 7-year-old boy, with 9 years of follow-up. During this time, progressive development of dental tissue was observed, including complete root formation. However, delayed dental eruption was evident. In view of these findings, we discuss the clinical presentation, pathogenesis, differential diagnosis, and treatment of RO.  相似文献   
90.
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