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31.
32.
Osama A. Smettei Sawsan Sayed Abdullah M Al Habib Fahad Alharbi Rami M. Abazid 《Journal of the Saudi Heart Association》2018,30(3):165-171
Background
Coronary computed tomography angiography (CCTA) is increasingly being used for the evaluation of coronary artery disease; however, radiation exposure remains a major limitation of its use.Objective
To compare image quality and radiation exposure in two groups of patients undergoing CCTA using a 256-slice dual-source helical computed tomography scanner with high-pitch (FLASH) or prospective [step-and-shoot (SAS)] gating protocols.Methods
A prospective, single-center study was performed in our cardiac center. In total, 162 patients underwent CCTA with either FLASH or SAS scanning protocols. Subjective image quality was graded on the basis of a four-point grading system (1, non-diagnostic; 2, adequate; 3, good; 4, excellent). Objective image quality was assessed using image signal, noise, and signal-to-noise ratio (SNR). The effective radiation dose was also estimated.Results
The clinical and demographic characteristics of the patients in both groups were similar. The median age of the patients in both groups was 48.43?years, and males accounted for 63% and 68.7% of the FLASH and SAS groups, respectively. We found that the subjective image quality obtained with the FLASH protocol was superior to that obtained with the SAS protocol (3.35?±?0.6?mSv vs. 2.82?±?0.61?mSv; p?<?0.001). Image noise was higher in the FLASH group but was not statistically significant (25.0?±?6.13 vs. 24.0?±?6.8; p?=?0.10), whereas the signal and SNR was significantly higher with the FLASH protocol than with the SAS protocol [(469?±?116 vs. 397?±?106; p?>?0.001) and (21.6?±?8.7?mSv vs. 16.6?±?7.7?mSv; p?<?0.001), respectively]. Radiation exposure was 62% lower in the FLASH protocol than in the SAS protocol, (1.9?±?0.4?mSv vs. 5.12?±?1.8?mSv; p?<?0.001).Conclusion
The use of 256-slice CCTA performed with the FLASH protocol has a better objective and subjective image quality as well as lower radiation exposure when compared with the use of prospective electrocardiography gating. 相似文献33.
Background
Obesity in type 2 diabetes patients is a serious health issue by itself; it is also associated with other health problems including psychiatric illnesses. The psychological effects of dieting and weight loss have been a matter of controversy in the field of obesity management.Objective
The aim of this study was to compare the impact of weight loss because of aerobic exercise training and dietary measures on psychological wellbeing and biochemical modulation in obese type 2 diabetes patients.Material and methods
One hundred obese type 2 diabetes patients of both sexes participated in this study, and were included into two equal groups. The first group (A) received aerobic exercise training, three sessions per week for three months combined with dietary measures. The second group (B) received no training intervention for three months.Results
There was a significant decrease in body mass index (BMI), leptin, total cholesterol (TC), low density lipoprotein cholesterol (LDL-c), triglycerides(TG), homeostasis model assessment-insulin resistance- index (HOMA-IR) , beck depression inventory (BDI ) & profile of mood states(POMS) and increase in high density lipoprotein cholesterol (HDL-c) & Rosenberg self-esteem scale (RSES) of group (A) after treatments, but the changes of group (B) were not significant. Moreover, there were significant differences between mean levels of the investigated parameters of group (B) and group (A) at the end of the study.Conclusion
Physical training and dietary measures can be used as methods of choice for psychological wellbeing and biochemical modulation in obese type 2 diabetes patients. 相似文献34.
35.
Ahmed S. Bahaj Haddad H. Alkaff Bashair N. Melebari Anwar N. Melebari Suhail I. Sayed Syeddah S. Mujtaba Sherif K. Abdelmonim Saeed A. Alghamdi Fares E. Alghamdi Omar A. Abu Suliman Mohammad A. Alessa Firas R. Abi Sheffah Anas H. Al-Tammas Rajab A. Al-Zahrani Osama A. Marglani John C. Heaphy Osama A. Bawazir Ameen Z. Alherabi 《Saudi medical journal》2020,41(10):1098
Objectives:To evaluate the accuracy and efficacy of fine-needle aspiration cytology (FNAC) in diagnosing thyroid nodules, correlating it with the histopathological findings.Methods:A retrospective evaluation of 314 patients was undertaken at a tertiary referral center of King Abdullah Medical City (KAMC), Makkah, Kingdom of Saudi Arabia, between 2010-2019. Patients who presented with thyroid swellings underwent ultrasonography and FNAC. If indicated, surgery was performed. The FNAC findings were compared to the final histopathological reports.Results:The findings for FNAC from our data set of 314 patients showed a sensitivity value of 79.8%, specificity of 82.1%, accuracy of 74.8%, positive predictive value of 74.8%, and negative predictive value of 85.9%.Conclusion:Our study showed that FNAC has high sensitivity and specificity in the initial evaluation of patients with thyroid nodules. When guided by ultrasonography, the accuracy can be markedly improved. Molecular markers once widely available can improve the diagnostic power of FNAC to be no less than the histopathologic evaluation of thyroid tissue. 相似文献
36.
37.
Purpose: The aim of this study was to determine effect of compressive cyclic loading on fatigue resistance and microleakage of monolithic CAD/CAM molar ceramic and composite crowns. Materials and Methods: Thirty‐two extracted molars were prepared to receive CEREC crowns according to manufacturer's guidelines using a special paralleling device (Parallel‐A‐Prep). Sixteen feldspathic ceramic crowns (VITABLOCS Mark II) (VMII) and 16 resin‐composite crowns (Paradigm‐MZ100 blocks) (PMZ) were milled using a CEREC‐3D machine. Eight crowns of each group were cemented to their respective teeth using self‐etching resin cement (Panavia‐F‐2.0) (PAN), and eight were cemented using self‐adhesive resin cement (RelyX‐Unicem‐Clicker) (RXU). Following storage for 1 week in water, specimens were subjected to uniaxial compressive cyclic loading in an Instron testing machine at 12 Hz for 1,000,000 cycles. Load was applied at the central fossa, and the cycle range was 60–600 N. Specimens were then subjected to microleakage testing. Data were statistically analyzed using factorial ANOVA and Post Hoc (Tukey HSD) tests. Results: All composite crowns survived compressive cyclic loading without fracture, while three ceramic crowns from the subgroup cemented with RXU developed surface cracks at the center of occlusal surfaces, extending laterally. Microleakage scores of ceramic crowns cemented with PAN were significantly lower than those of the other three subgroups (p < 0.05). Conclusions: After 1,000,000 cycles of compressive cyclic loading, PMZ composite molar crowns were more fatigue‐resistant than VMII ceramic crowns. Cement type had a significant effect on fatigue resistance of the ceramic crowns but not the composite ones. Microleakage scores of ceramic crowns cemented with PAN were significantly lower than those of the other subgroups (p < 0.05). 相似文献
38.
39.
Mahmoud Rafaat Kandil Kawthar Abdel-Motagally Fadel Hossam Eldin Khalifa Mostafa Kamel Ghanem Khaled Osama Mohamed 《Neurological research》2013,35(3):232-241
AbstractObjectives: Headache is one of the most common complaints in medicine. Epidemiological and population-based studies reported that migraine has a variable prevalence worldwide. This study was done to estimate the prevalence of migraine across various age groups in Assiut district, Egypt.Methods: This is a door-to-door study. It included 4700 randomly selected individuals.Results: Headache was reported in 1668 subjects (35.49%), of them, 87.65% (n = 1462) had primary headaches. Migraine prevalence was 10.51% with female-to-male ratio of 2.4:1 particularly in ages of 20–40 years. The mean age of patients was 31.46 ± 13.39 years and age at onset was 24.16 ± 12.10 years. Nearly, 63.5% had frequent attacks, 65.2% of the attacks were severe enough to stop daily activities and lasted for >1 day in 32.5% of females compared to 40.7% and 14.5% for males. Chronic or daily migraine was more in females (35.3% versus 20.7% for males). Approximately, 5.6% had chronic migraine and 1.2% had daily migraine from the start, while 24.2% had transformation from episodic to chronic migraine within 6.1 ± 4.4 years. Migraine was prevalent among those with middle educational levels and labor workers. The duration of migraine attacks was found to reduce with age but the chronic/daily migraine increased with age. Hypertension, anxiety, irritable bowel syndrome, and depression were common comorbidities with migraine.Conclusions: We believe that the work done in this study is informative as it determined the actual prevalence of migraine across various age groups and the important predictors of change in the severity, duration, and frequency of migraine in our locality. 相似文献
40.
Elisabeth C. Caparelli Brooke Schleyer Tianye Zhai Hong Gu Osama A. Abulseoud Yihong Yang 《Neuromodulation》2022,25(4):633-643
ObjectivesTranscranial magnetic stimulation (TMS) has been extensively used for the treatment of depression, obsessive-compulsive disorder, and certain neurologic disorders. Despite having promising treatment efficacy, the fundamental neural mechanisms of TMS remain understudied.Materials and MethodsIn this study, 15 healthy adult participants received simultaneous TMS and functional magnetic resonance imaging to map the modulatory effect of TMS when it was applied over three different sites in the dorsolateral prefrontal cortex. Independent component analysis (ICA) was used to identify the networks affected by TMS when applied over the different sites. The standard general linear model (GLM) analysis was used for comparison.ResultsICA showed that TMS affected the stimulation sites as well as remote brain areas, some areas/networks common across all TMS sites, and other areas/networks specific to each TMS site. In particular, TMS site and laterality differences were observed at the left executive control network. In addition, laterality differences also were observed at the dorsal anterior cingulate cortex and dorsolateral/dorsomedial prefrontal cortex. In contrast with the ICA findings, the GLM-based results mainly showed activation of auditory cortices regardless of the TMS sites.ConclusionsOur findings support the notion that TMS could act through a top-down mechanism, indirectly modulating deep subcortical nodes by directly stimulating cortical regions.Clinical Trial RegistrationThe Clinicaltrials.gov registration number for the study is NCT03394066. 相似文献