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101.
102.
Zhen-Yu Wu Young Joo Lee Yungil Shin Soojeong Choi Soo Yeon Baek Jung Whan Chun Loai Saleh Albinsaad Woo Jung Choi Namkug Kim BeomSeok Ko 《JOURNAL OF BREAST CANCER》2021,24(3):349
Tumor localization is challenging in the context of ductal carcinoma in situ (DCIS) treated with breast-conserving surgery. Conventional localization methods are generally performed under the guidance of ultrasonography or mammography and are rarely performed with magnetic resonance imaging (MRI), which is more sensitive than the aforementioned modalities in detecting DCIS. Here, we report the application of MRI-based individualized 3-dimensional (3D)-printed breast surgical guides (BSGs) for patients with breast cancer. We successfully resected indeterminate and suspicious lesions that were only detected using preoperative MRI, and the final histopathologic results confirmed DCIS with clear resection margins. MRI guidance combined with 3D-printed BSGs can be used for DCIS localization, especially for lesions easily detectable using MRI only. 相似文献
103.
Beata Bobrowska Wojciech Zasada Andrzej Surdacki Tomasz Rakowski Pawe? Kleczyński Jolanta ?wierszcz Olga Kruszelnicka Renata Rajtar-Salwa Saleh Arif Danuta Sorysz Dariusz Dudek Jacek S. Dubiel 《International journal of medical sciences》2013,10(10):1361-1366
Background. Patients with degenerative aortic stenosis (AS) exhibit elevated prevalence of coronary artery disease (CAD) and internal carotid artery stenosis (ICAS). Our aim was to investigate prevalence of significant CAD and ICAS in relation to demographic and cardiovascular risk profile among patients with severe degenerative AS.Methods. We studied 145 consecutive patients (77 men and 68 women) aged 49-91 years (median, 76) with severe degenerative AS who underwent coronary angiography and carotid ultrasonography in our tertiary care center. The patients were divided into two groups according to the presence of either significant CAD (n=86) or ICAS (n=22).Results. The prevalence of significant CAD or ICAS was higher with increasing number of traditional risk factors (hypertension, hypercholesterolemia, diabetes, smoking habit) and decreasing renal function. We found interactions between age and gender in terms of CAD (p=0.01) and ICAS (p=0.06), which was confirmed by multivariate approach. With the reference to men with a below-median age, the prevalence of CAD or ICAS increased in men aged >76 years (89% vs. 55% and 28% vs. 14%, respectively), whereas the respective percentages were lower in older vs. younger women (48% vs. 54% and 7% vs. 17%).Conclusions. In severe degenerative AS gender modulates the association of age with coronary and carotid atherosclerosis with its lower prevalence in women aged >76 years compared to their younger counterparts. This may result from a hypothetical “survival bias”, i.e., an excessive risk of death in very elderly women with severe AS and coexisting relevant coronary or carotid atherosclerosis. 相似文献
104.
Mohamed A. Salem Rasha Ali Radwan Eman Sherien Mostafa Saleh Alseekh Alisdair R. Fernie Shahira M. Ezzat 《RSC advances》2020,10(52):31511
Aging is an unavoidable fate that afflicts all life, during this process in mammals reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. Therefore, the maintenance of antioxidant homeostasis is an important anti-aging strategy for skin. Nature has excellent anti-aging remedies that act externally as well as internally to delay the visual signs of aging. In view of this fact, the present study investigates the in vitro anti-aging activity of five medicinal plants belonging to phenolic rich families namely Rosmarinus officinalis, Lavandula officinalis, Matricaria chamomilla, Camellia sinensis and Pelargonium graveolens. The selected plants are those most frequently used in the preparation of ethnomedicinal recipes for the prevention or treatment of aging. The inhibitory effects of the ethanolic and aqueous extracts of the five selected plants on the activity of tyrosinase, elastase, and collagenase enzymes were investigated. Furthermore, the chemical composition of the plants and the antioxidant capacity of their extracts were assessed. The results showed that R. officinalis had the highest total phenolics content which was correlated with its potent antioxidant and anti-aging activities. To pinpoint the active metabolites in the tested extracts, we evaluated the metabolite variations using ultra-performance liquid chromatography coupled with high resolution electrospray ionization-tandem mass spectrometry (UPLC-HR-ESI-MS/MS). Multivariate data analysis (MVDA) revealed that R. officinalis significantly accumulated metabolites from the aromatic diterpenoid, flavonoid and phenolic acid classes. These results indicate that rosemary can be used for further development of topical preparations with anti-aging properties.Aging is an unavoidable fate that afflicts all life, during this process in mammals, reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. 相似文献
105.
Veldtman Gruschen Possner Mathias Mohty Dania Issa Ziyad Alsaleh Monerah AlMarzoog AlJuhara Thaar Emmanual Shisamma Salam Yezan AlHabdan Mohammed Saleh Alsaied Tarek Rathod Rahul H. Siblini Ghassan Vriz Olga 《The international journal of cardiovascular imaging》2021,37(9):2651-2660
The International Journal of Cardiovascular Imaging - Abnormal atrial mechanics in biventricular circulations have been associated with elevated left heart filling pressures. Similar associations... 相似文献
106.
Altaf Hussain Shah Hesham Saleh Khalil Mohammed Zaheer Kola 《Saudi Dental Journal》2015,27(3):165-170
Automated Implantable Cardioverter Defibrillators (AICD), simply known as an Implantable Cardioverter Defibrillator (ICD), has been used in patients for more than 30 years. An Implantable Cardioverter Defibrillator (ICD) is a small battery-powered electrical impulse generator that is implanted in patients who are at a risk of sudden cardiac death due to ventricular fibrillation, ventricular tachycardia or any such related event. Typically, patients with these types of occurrences are on anticoagulant therapy. The desired International Normalized Ratio (INR) for these patients is in the range of 2–3 to prevent any subsequent cardiac event. These patients possess a challenge to the dentist in many ways, especially during oral surgical procedures, and these challenges include risk of sudden death, control of post-operative bleeding and pain.This article presents the dental management of a 60 year-old person with an ICD and concomitant anticoagulant therapy. The patient was on multiple medications and was treated for a grossly neglected mouth with multiple carious root stumps. This case report outlines the important issues in managing patients fitted with an ICD device and at a risk of sudden cardiac death. 相似文献
107.
Mohamed I. El-Anwar Salah A. Yousief Tarek A. Soliman Mahmoud M. Saleh Wael S. Omar 《Saudi Dental Journal》2015,27(4):201-207
Objective
This study aimed to evaluate stress patterns generated within implant-supported mandibular overdentures retained by two different attachment types: ball and socket and locator attachments.Materials and methods
Commercial CAD/CAM and finite element analysis software packages were utilized to construct two 3D finite element models for the two attachment types. Unilateral masticatory compressive loads of 50, 100, and 150 N were applied vertically to the overdentures, parallel to the longitudinal axes of the implants. Loads were directed toward the central fossa in the molar region of each overdenture, that linear static analysis was carried out to find the generated stresses and deformation on each part of the studied model.Results
According to FEA results the ball attachment neck is highly stressed in comparison to the locator one. On the other hand mucosa and cortical bone received less stresses under ball and socket attachment.Conclusions
Locator and ball and socket attachments induce equivalent stresses on bone surrounding implants. Locator attachment performance was superior to that of the ball and socket attachment in the implants, nylon caps, and overdenture. Locator attachments are highly recommended and can increase the interval between successive maintenance sessions. 相似文献108.
Ahmed Mousa Altaf A. Kondkar Saleh A. Al-Obeidan Taif A. Azad Tahira Sultan Essam Osman Khaled K. Abu-Amero 《Saudi medical journal》2015,36(6):671-677
Objectives:
To compare the mean total antioxidant status (TAS) among 3 glaucoma types, namely: pseudoexfoliation glaucoma (PEG), primary open angle glaucoma (POAG), and primary angle closure glaucoma (PACG), and study its potential association with various clinical glaucoma-parameters.Methods:
In this case-control study, plasma samples were obtained between September 2013 and October 2014 from 340 glaucoma patients (PEG [n=54]; POAG [n=147]; PACG [n=139]), and 351 controls of matching age, gender, ethnicity, and 5 different systemic co-morbidities from King Abdulaziz University Hospital, Riyadh, Saudi Arabia. The TAS in all samples was determined by a colorimetric-based assay.Results:
The mean±standard deviation of TAS was significantly lower among cases: 0.77±0.32 than controls: 1.1±0.22, p<0.0001. Moreover, the TAS levels were significantly different across the 3 types of glaucoma: 0.86±0.24 in PEG, 0.47±0.32 in POAG, and 0.98±0.41 in PACG (all p<0.0001). In addition, there was a significant correlation between TAS and age at onset (Pearson correlation coefficient [R] 0.17, p<0.0001), cup/disc ratio (R: -0.13, p=0.004), and number of anti-glaucoma medications (R: -0.16, p=0.001).Conclusion:
Our findings provide evidence that plasma TAS levels are decreased in patients with glaucoma, more so in POAG and PEG than PACG, supporting the hypothesis that decreased antioxidative defense and/or increased oxidative stress may have a critical role in the pathogenesis of glaucoma.Glaucoma is a progressive optic neuropathy associated with optic nerve damage, and is one of the most leading cause of blindness worldwide.1 Elevated intraocular pressure (IOP) as a result of reduction in normal aqueous outflow is a major causal risk factor that is well supported by animal studies.2-4 Although IOP is considered a major risk factor for glaucoma,2,3 other concomitant factors affecting the pathophysiology of glaucomatous retinal ganglion cell (RGC) death include retinal ischemia,5 nutritional status,6 and oxidative stress.7 There is evidence of oxidative damage in ocular diseases, such as cataract and age-related macular degeneration.8 In addition, significant oxidative damage has been demonstrated in human trabecular meshwork (TM) cells of patients with glaucoma,7 causing elevated IOP and visual field damage.9 Furthermore, our previous studies have documented mitochondrial abnormalities10-12 (oxidative stress marker), and glutathione-S-transferase (antioxidant) gene (GST) polymorphisms to be associated with various types of glaucoma.13 It is clearly evident from the literature, and our own studies, that oxidative stress mechanisms play a critical role in the pathogenesis of glaucoma. Previous studies had demonstrated reduced total antioxidant capacity in aqueous humor and blood samples from patients with glaucoma.14-17 To evaluate the role of oxidative stress in different types of glaucoma we had previously investigated total antioxidants status (TAS) in the plasma of pseudoexfoliation glaucoma (PEG) patients,18 primary angle closure glaucoma (PACG) patients,19 and in the plasma of primary open angle glaucoma (POAG) patients.20 As an extension to these studies, here, we compare the mean TAS level among these 3 glaucoma types, and study the potential association between the TAS level and various clinical parameters important to each type of glaucoma.18-20 相似文献109.
Khairy MA Zoheir Ahmed A Abd-Rabou Gamaleldin I Harisa Abdelkader E Ashour Sheikh Fayaz Ahmad Sabry M Attia Saleh A Bakheet Hala E Abdel-Hamied Adel R Abd-Allah Ashok Kumar 《International journal of clinical and experimental pathology》2015,8(8):8821-8831
IQGAPs genes play critical role in either induction or suppression of cancer and its progression, however the relationship between Ras genes and these genes are still unclear. In this study, we tried to understand the mechanistic action of IQGAPs genes and its correlation with Ras genes in mouse hepatic cancer model. The genetic expressions of IQGAP1, IQGAP2, IQGAP3, Hras, Kras, Nras, Mras, Caspase3, and BAX were followed in both hepatocellular carcinoma and normal liver cells of Balbc mice. Genotoxic agent diethylnitrosamine (DEN)-induced hepatic cancer model was induced in male mice and recorded the occurrence of hepatocellular carcinoma by morphological and histological changes in the liver. It was observed that mRNA expressions of IQGAP1, Hras, Kras, Nras, Mras, Caspase3, and BAX genes were highly elevated in hepatocellular carcinoma cells when compared with normal liver cells, additionally their expressions increased by concentrating the dose of DEN. While, the expressions of IQGAP2 and IQGAP3 were significantly decreased in hepatocellular carcinoma cells when compared with normal liver cells, as well as their expressions decreased more with increasing the dose of DEN. It was concluded from this study that IQGAP1 has a strong signaling relationship with Ras genes in induction of cancer and it is considered as a key gene for induction or suppression of the hepatocellular carcinoma. 相似文献
110.
The use of fibers in cementitious composites yields numerous benefits due to their fiber-bridging capabilities in resisting cracks. Therefore, this study aimed to improve the shear-resisting capabilities of conventional concrete through the hybridization of multiple synthetic fibers, specifically on reinforced concrete structures in seismic-prone regions. For this study, 16 hybrid fiber-reinforced concretes (HyFRC) were developed from the different combinations of Ferro macro-synthetic fibers with the Ultra-Net, Super-Net, Econo-Net, and Nylo-Mono microfibers. These hybrids were tested under direct shear, resulting in improved shear strength of controlled specimens by Ferro-Ultra (32%), Ferro-Super (24%), Ferro-Econo (44%), and Ferro-Nylo (24%). Shear energy was further assessed to comprehend the effectiveness of the fiber interactions according to the mechanical properties, dosage, bonding power, manufactured material, and form of fibers. Conclusively, all fiber combinations used in this study produced positive synergistic effects under direct shear at large crack deformations. 相似文献