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91.
ObjectiveThe current study aimed at examining a fluoride containing bioactive glass (BiominF®) paste as a temporary filling material capable of remineralizing the demineralized enamel or dentin, and its ability to decrease a simulated dentinal fluids pressure on the resin/dentin interface, without affecting the shear bond strength of a universal bonding agent to enamel and dentin.Methods60 premolars were utilized for the acid resistance, trans-microradiography (TMR) and shear bond strength (SBS) experiments. Enamel and dentin discs were demineralized for 4 days to create a subsurface demineralized zone followed by applying BiominF® paste, 1.23% acidulated phosphate fluoride, or a temporary filling material for 24 h.30 extracted human non-carious third molars were utilized for the pulpal pressure experiment in which direct communication to the pulp chamber was created by cutting at a level approximately 1 mm below the cemento-enamel junction while the coronal enamel was ground to expose mid coronal dentin. The dentin surface was exposed to a simulated pulpal pressure. The dentin surfaces had BiominF® paste, an oxalate desensitizing agent, or temporary filling material followed by application of a universal adhesive system.ResultsOne way ANOVA showed that BiominF® paste remineralized effectively the demineralized enamel or dentin, did not affect the bond strength of the enamel and dentin surfaces to the tested adhesive system p < 0.05, and improved the acid resistance of the demineralized enamel and dentin against a secondary erosive challenge. Moreover, BiominF® paste decreased the nanoleakage expression in the dentin/adhesive interface exposed to a simulated pulpal pressure.SignificanceBiominF® paste may serve as a temporary filling material that may improve the longevity of adhesive restorations and help to conserve tooth structures by preserving the demineralized enamel and dentin form cutting during cavity preparation. 相似文献
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Rehab M. Samaka Moshira M. Abd El‐Wahed Hayam A. Aiad Mona A. Kandil Dalia R. Al‐Sharaky 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(4):316-328
John Cunningham virus (JCV) encodes an oncogenic T‐antigen, which is capable of interacting with key growth regulatory pathways. JCV definite role as causal agent of human cancer, still awaits final confirmation. The present study was conducted to assess the possible role of JCV in Egyptian colorectal carcinoma (CRC) and correlate the expression with the clinicopathological features and survival. JCV in situ hybridization (ISH) signals and large T antigen immunoreactivity were examined in 87 colonic specimens. Positive glandular JCV ISH signals were detected in 20%, 25% and 40% of normal, adenoma and CRC cases respectively. Stromal JCV ISH signals were identified in 26% of CRC cases and 5% of adenoma however, normal mucosa did not show stromal positivity with significant difference (p = 0.03). Glandular JCV expression was significantly associated with high grade (p = 0.03), high mitotic index (p=0.02) and low apoptotic index (p = 0.00). Positive stromal signals were significantly associated with low apoptosis (p = 0.00). No positive nuclear immunostaining of JCV large T antigen was detected in all specimens. JCV stromal expression was the 2nd most powerful indicator of short survival and bad prognosis (p = 0.03) in CRC patients. JCV might play an etiological role in CRC tumorogenesis and short survival in Egyptian CRC patients. 相似文献
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Nahed Mounir Sherif Mona Mahmoud Arafa Soha Eldessouki Ibrahim Salwa Galal Moussa 《The Egyptian Rheumatologist》2013,35(3):121-126
Aim of the workThe aim of the present study was to measure the level of the chemokine CXC ligand 13 protein (CXCL13) in the plasma and unstimulated saliva of rheumatoid arthritis (RA) patients in order to find out its role in the disease activity and its relation to secondary Sjögren’s syndrome (sSS).Patients and methodsThe study was conducted on thirty rheumatoid arthritis patients attending the Outpatient Clinic of Rheumatology and Rehabilitation department of Ain shams University Hospitals. The patients’ group had been classified into group (1) which included fifteen RA patients associated with sSS diagnosed according to the American–European Consensus Group Classification Criteria and group (2) which included fifteen RA patients not associated with sSS. Ten healthy subjects were included as a control group. Patients were subjected to full history taking, clinical examination, and laboratory detection of CXCL13 level in the plasma and saliva of patients as well as the control groups using ELISA technique. Assessment of disease activity in RA patients was done using the disease activity score (DAS28).ResultsPlasma levels of CXCL13 were significantly higher in RA patients than control group (p < 0.001). Plasma levels of CXCL13 were significantly correlated with the RA disease activity (r = 0.677, p < 0.001) and disease duration (r = 0.406, p < 0.05), while the salivary levels were higher in those with sSS and correlated with sSS disease duration (r = 0.536, p < 0.05). A highly significant correlation was found between salivary CXCL13 and severity of sSS (r = 0.816, p < 0.001). Salivary levels of CXCL13 above 110 pg/ml may diagnose sSS with sensitivity 80% and specificity 84%.ConclusionThe results of this preliminary study point out the importance of CXCL13 as a marker for RA disease activity, its role in diagnosing sSS, and estimation of sSS severity. 相似文献
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Adam M. Garber Robert J. Mentz Hussein R. Al-Khalidi Linda K. Shaw Mona Fiuzat Christopher M. O’Connor Eric J. Velazquez 《Journal of thrombosis and thrombolysis》2016,41(3):365-373
We aimed to characterize the independent predictors of LVT following STEMI and the association with outcomes. The clinical predictors of left ventricular thrombus (LVT) formation after ST-segment elevation myocardial infarction (STEMI) are not well-defined in the contemporary era. We performed a retrospective analysis of STEMI patients at Duke from 2000 to 2011 who had a transthoracic echocardiogram within 90 days post-STEMI and compared patients with and without LVT (LVT+ vs. LVT?). Univariate Cox proportional hazards regression models of baseline characteristics were examined and significant variables were used in a multivariable model to assess adjusted relationships with LVT. A multivariable Cox PH survival model with covariate adjustments was used for assessment of LVT and long-term mortality. Of all eligible patients, 1734 patients met inclusion criteria and 4.3 % (N = 74) had a LVT. LVT+ patients tended to have a history of heart failure (HF) and higher initial troponin compared to LVT- patients. After adjustment, higher heart rate, non-white race, HF severity, and presence of left anterior descending artery (LAD) disease were independent predictors of LVT. There was a trend toward an association between LVT and increased all-cause mortality (HR 1.36; 95 % CI 0.84–2.21, P = 0.22), however this was not statistically significant. LVT was seen in over 4 % of this contemporary post-STEMI population. Several baseline characteristics were independently associated with LVT: Heart rate, HF severity, LAD disease, and non-white race. Prospective studies are warranted to determine whether anticoagulation in patients at increased risk for LVT improves outcomes. 相似文献
96.
Naïka C. Gabriel Elizabeth Sloand Faye Gary Mona Hassan Desiree R. Bertrand Jacquelyn Campbell 《Health care for women international》2016,37(7):773-789
The purpose of this study was to explore the perceptions of violence against women (VAW) held by Haitian men to gain a better understanding of why VAW occurs. Women in Haiti have experienced significant violence, both before and following the 2010 earthquake. Fifteen men aged 26 to 47 participated in a focus group. The data revealed three themes: men's beliefs about VAW and its context, factors influencing VAW, and recommended interventions. When approaching VAW, men must be part of the collective effort. Their insights are valuable when planning and implementing interventions to decrease VAW in Haiti and worldwide. 相似文献
97.
Ahmed Faeq Hussein Shaiful Jahari Hashim Ahmad Fazli Abdul Aziz Fakhrul Zaman Rokhani Wan Azizun Wan Adnan 《Journal of medical systems》2018,42(1):15
The non-stationary and multi-frequency nature of biomedical signal activities makes the use of time-frequency distributions (TFDs) for analysis inevitable. Time-frequency analysis provides simultaneous interpretations in both time and frequency domain enabling comprehensive explanation, presentation and interpretation of electrocardiogram (ECG) signals. The diversity of TFDs and specific properties for each type show the need to determine the best TFD for ECG analysis. In this study, a performance evaluation of five TFDs in term of ECG abnormality detection is presented. The detection criteria based on extracted features from most important ECG signal components (QRS) to detect normal and abnormal cases. This is achieved by estimating its energy concentration magnitude using the TFDs. The TFDs analyse ECG signals in one-minute interval instead of conventional time domain approach that analyses based on beat or frame containing several beats. The MIT-BIH normal sinus rhythm ECG database total records of 18 long-term ECG sampled at 128 Hz have been analysed. The tested TFDs include Dual-Tree Wavelet Transform, Spectrogram, Pseudo Wigner-Ville, Choi-Williams, and Born-Jordan. Each record is divided into one-minute slots, which is not considered previously, and analysed. The sample periods (slots) are randomly selected ten minutes interval for each record. This result with 99.44% detection accuracy for 15,735 ECG beats shows that Choi-Williams distribution is most reliable to be used for heart problem detection especially in automated systems that provide continuous monitoring for long time duration. 相似文献
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