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排序方式: 共有1612条查询结果,搜索用时 19 毫秒
1.
Mohammed Ghonime Riham Shawky Hesham Soliman Ramadan El-Domany Ahmed Abdelaziz 《Immunological investigations》2015,44(3):237-252
A group of 11 medicinal plants, including Lavandula pubescens, Trigonella foenugricium, Salsola schweinforthi, Calligonum comosum, Silene succulenta, Silene villosa, Bogonvillea glabra, Cakile maritime, Gomphrene celesoids, Mirabilis jalaba, and Silene nocturna growing in Egypt, were extracted and examined for their immunomodulatory and antioxidant activities. RAW 264.7 cells were recruited to investigate the immunomodulatory effect through multiple parameters analysis. First, the proliferation index of macrophages cells was evaluated revealing that Trigonella foenugricium, Silene succulenta and Silene villosa have a significant cytotoxic effect on RAW cells. Interestingly, we observed enhancement of macrophages phagocytic function of by all extracts except Cakile maritime, Gomphrena celosioides and Silene nocturna. Afterwards, macrophages were challenged by incubation with LPS and the effect of various extracts on inflammatory responses was investigated; the generation of NO from activated macrophage was substantially suppressed by 7 extracts namely, Trigonella foenugricium, Calligonum comosum, Silene succulenta, Bougainvillea glabra, Mirabilis jalaba, Gomphrena celosioides and Silene nocturna. TNF-α was decreased by percentage range from 3.8 to 85.8% and Trigonella foenugricium extract showed the highest inhibition of TNF-α release. All extracts except Trigonella foenugricium, Salsola schweinforthi, Silene succulenta and Mirabilis jalaba significantly inhibited COX-2 production from stimulated macrophage. Moreover, evaluating the potential antioxidant activity of these extracts showed that Trigonella foenugricium, Salsola schweinforthi, Calligonum comosum, Bogonvillea glabra and Mirabilis jalaba exhibited some antioxidant activities. Taken together, our results suggest that some of these extracts may have a considerable antinflammatory and antioxidant effects and may be a potential therapeutic choice in the treatment of inflammatory diseases. 相似文献
2.
Fouad Ayoub Maria Saadeh Hasan Fayyad-Kazan Ramzi Haddad 《Journal of cranio-maxillo-facial surgery》2019,47(2):273-279
Introduction
The majority of previous research delineating the morphological characteristics of the orolabial region has been on Caucasian populations, with very minor research on Mediterranean populations, and none on the Lebanese population.Aim
The primary aim was to collect information on the gender-specific 3D morphology of the mouth and lips in young Middle Eastern adults. The secondary aim was to explore the presence of associations between orolabial morphology and age and body mass index (BMI), and to assess correlations between linear orolabial dimensions and area/volume measures.Methods
The study used non-invasive stereophotogrammetry to collect information on gender-specific 3D labial morphology (linear distances, areas, and volumes) for 122 adult Lebanese subjects, aged 18–30 years (47 males, 75 females). Associations between labial morphology and age and body mass index were assessed, in addition to correlations between linear orolabial dimensions and area/volume measures.Results
All linear, angular, area, and volume lip measurements displayed significant variability. Both lip area and volume were smaller in the upper than in the lower lip. Eighteen out of the 20 linear measurements were significantly larger in males. The ratio, area, and volume measurements mostly displayed no statistically significant gender dimorphism.Conclusions
Alongside presenting the first documented report on anthropometric labial measurements of a young Lebanese adult population, this research highlights the presence of gender dimorphism in linear and angular measurements, but not in area and volume measurements, and a strong association between certain linear labial measurements and lip area and volume. In addition, it presents pilot data on the association between labial anthropometry and body mass index. 相似文献3.
Al-Omiri MK Rayyan MR Abu-Hammad O 《Journal of the American Dental Association (1939)》2011,142(3):289-300
BackgroundThe authors conducted a study to analyze the stress concentration areas in a tooth restored with a post-retained crown under various conditions.Materials and MethodsThe authors constructed a three-dimensional finite element model describing a maxillary second premolar restored with an all-ceramic crown supported by a titanium post and a resin-based composite core. They applied static vertical and horizontal loads of 100 newton to the cusp tip of the crown and recorded Von Mises and tensile stress values. The variables investigated were the presence of the post, coronal and apical post extensions, post diameter, post shape, and post and core material.ResultsThe study results showed that horizontal loading generated higher levels of stress than did vertical loading. The greatest stress levels were concentrated at the cervical region and at the post-dentin interface in all models. Under both loads, a higher modulus of elasticity of the post material and a wider post diameter were associated with increased stress values at the post-dentin interface. Reduction of the post extension above the level of bone was associated with increased dentinal stresses near the apex of the post.ConclusionsAlthough endodontic posts provide retention for coronal restorations, they result in dentinal stress values higher than those of crowns without posts. Posts that had a similar modulus of elasticity to dentin and smaller diameters were associated with better stress distribution. Resting coronal restorations on sound dental tissues affected stress distribution more than did the core material or the length of the coronal post extension.Clinical ImplicationsMany factors influence the distribution of stress within dentin and, consequently, the fracture resistance of teeth restored with post-retained crowns. Clinicians need to keep these factors in mind when performing endodontic procedures that involve placement of post-retained crowns to ensure optimal success. 相似文献
4.
5.
El-Solh AA Saltzman SK Ramadan FH Naughton BJ 《Archives of physical medicine and rehabilitation》2000,81(10):1388-1393
OBJECTIVE: To develop an artificial neural network (ANN) designed to predict discharge destination from postacute geriatric rehabilitation units. DESIGN: Nonconcurrent prospective study. SETTING: Postacute geriatric rehabilitation units: a 20-bed unit in a nonproprietary skilled nursing facility and a 40-bed unit in a suburban private facility. PATIENTS: Consecutive sample of 661 patients admitted between January 1995 and February 1999, including a derivation group of 452 patients and a validation group of 209 patients. INTERVENTIONS: A feed-forward, back-propagation neural network to predict discharge destination. MAIN OUTCOME MEASURE: Discharge destination from postacute geriatric rehabilitation. RESULTS: An ANN was trained on clinical pattern set derived from 452 patients and validated prospectively on 209 consecutive patients admitted to postacute geriatric rehabilitation units. The neural network achieved a sensitivity of 85.7% (95% confidence interval [CI], 83.7-89.4) and specificity of 94.1% (95% CI, 84.4-99.1) in identifying discharge destination with a corresponding area under the curve of 95.7% (95% CI, 92.1-98.3). CONCLUSION: An ANN can predict discharge to the community postacute rehabilitation with a high degree of accuracy. It could have particular value to predict return to the community for older adults with multiple comorbidities after an acute hospitalization. 相似文献
6.
W. Bouida H. Baccouche M. Sassi Z. Dridi T. Chakroun I. Hellara R. Boukef M. Hassine F. Added R. Razgallah I. Khochtali S. Nouira On behalf of the Ramadan Research Group 《Thrombosis journal》2017,15(1):15
Background
The effects of Ramadan fasting (RF) on clopidogrel antiplatelet inhibition were not previously investigated. The present study evaluated the influence of RF on platelet reactivity in patients with high cardiovascular risk (CVR) in particular those with type 2 diabetes mellitus (DM).Methods
A total of 98 stable patients with ≥2 CVR factors were recruited. All patients observed RF and were taking clopidogrel at a maintenance dose of 75 mg. Clinical findings and serum lipids data were recorded before Ramadan (Pre-R), at the last week of Ramadan (R) and 4 weeks after the end of Ramadan (Post-R). During each patient visit, nutrients intakes were calculated and platelet reactivity assessment using Verify Now P2Y12 assay was performed.Results
In DM patients, the absolute PRU changes from baseline were +27 (p = 0.01) and +16 (p = 0.02) respectively at R and Post-R. In addition, there was a significant increase of glycemia and triglycerides levels with a significant decrease of high-density lipoprotein. In non DM patients there was no significant change in absolute PRU values and metabolic parameters. Clopidogrel resistance rate using 2 cut-off PRU values (235 and 208) did not change significantly in DM and non DM patients.Conclusions
RF significantly decreased platelet sensitivity to clopidogrel in DM patients during and after Ramadan. This effect is possibly related to an increase of glycemia and serum lipids levels induced by fasting.Trial registration
Clinical Trials.gov NCT02720133. Registered 24 July 2014.Retrospectively registered.7.
8.
Reem Abdelraouf Elsharkawy Tarek Habeeb Ramadan Mohamed Aboelnour Badran 《Egyptian Journal of Anaesthesia》2018,34(1):15-19
Background
An intra-articular injection is considered the leading method for postoperative analgesia after knee surgery. Dexmedetomidine has peripheral and central analgesic effect. The study was conducted to compare between the analgesic effect of intra-articular and intravenous dexmedetomidine in arthroscopic knee surgery.Methods
One hundred patients underwent elective arthroscopic knee surgery had randomly allocated into two equal groups. (Group IA) the patients had received 1?µg/kg dexmedetomidine added to local anesthetic bupivacaine intra-articularly while (Group IV): the patients had received 1?µg/kg dexmedetomidine added to 20?ml saline over 10?min starting with local intra-articular anaesthesia. Pain VAS, heart rate, mean arterial blood pressure, total requirement for analgesic, the first request for it, and first time to mobilize within the first 24?h were assessed.Results
The VAS were significantly lower in IA group at 4 and 6?h during rest and at 4, 6, 12?h during motion, Also, the duration of first analgesic request was significantly prolonged in IA group than IV group (11?h?±?2.2 vs 9.2?h?±?3.2, respectively) (p value .001). Moreover, the total analgesic consumption was significantly lesser IA group compared with that in IV group (87?±?27.7?mg Vs 108?±?37.6?mg, respectively) (p value .002). No postoperative adverse effects were recorded.Conclusion
Intra-articular dexmedetomidine when added to local anaesthesia improves the postoperative analgesic profile with decrease the needs for postoperative analgesia and prolong the time for analgesic request.Clinical trial registration:NCT02730845. 相似文献9.
Behavior of In Situ Cross‐Linked Hydrogels with Rapid Gelation Kinetics on Contact with Physiological Fluids 下载免费PDF全文
Ramadan Diryak Vassilis Kontogiorgos Muhammad U. Ghori Paul Bills Ahmed Tawfik Gordon A. Morris Alan M. Smith 《Macromolecular chemistry and physics.》2018,219(8)
The impact of different physiological fluids on the rheological properties of gellan gum is investigated using a commercially available rheometer with a modified lower plate. The power of this method is demonstrated by measuring in real time, the rapid gelation kinetics, and gel strength of gellan gum exposed to simulated gastric fluid, lacrimal fluid, saliva, and wound fluid (all having a different ionic composition), highlighting potential use in the intelligent design of in situ gelling delivery systems. Changes in rheological behavior are examined in situ, gelation kinetics are modeled, and microstructure analyzed in the different simulated physiological environments. 相似文献
10.
This study examined the relationship between oxidation–reduction potential (ORP) in frozen-thawed semen and the post-thaw sperm parameters. Levels of ORP were measured in 25 samples from men presenting for routine infertility work-up and were expressed as millivolt (mV)/106 sperm/ml. Frozen-thawed samples were examined for post-thaw total motility (TM%), progressive motility (PM%), total sperm count (TSC) and ORP. The cryo-survival rate (CSR) was calculated as post-thaw TM/pre-freeze TM × 100. Data are provided as median and interquartile range (25th and 75th percentiles). The post-thaw TM% (10.0% [4.00%, 15.1%]), PM% (5.88% [2.97%, 9.33%]) and TSC (12.5 [10.0, 17.5] × 106 sperm) were significantly lower than the pre-freeze TM% (45.9% [32.9%, 59.1%], PM% (31.5% [24.4%, 40.0%] and TSC (120 [90, 250] ×106 sperm) (p < .001). Post-thaw ORP (2.62 [2.52, 3.13] mV/106 sperm/ml) was significantly higher than pre-freeze ORP (0.73 [0.54, 1.21] mV/106 sperm/ml; p < .001). The CSR was 21.7% (11.3%, 31.9%). The post-thaw seminal ORP was negatively correlated with post-thaw TM% (r = −.5; p = .02), PM% (r = −.41; p = .03), TSC (r = −.60; p = .03) and CSR (r = −.52; p = .01). Increased levels of ORP are significantly correlated with poor post-thaw sperm quality and CSR. 相似文献