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Oguz Ozan PhD Kaan Orhan PhD Secil Aksoy DDS Murat Icen DDS Burak Bilecenoglu PhD Bayram Ufuk Sakul PhD 《Journal of prosthodontics》2013,22(1):42-48
Purpose: The aim of this study was to compare vertical and horizontal mandibular alveolar bone resorption by measuring bone morphological variation in Kennedy Class II removable partial denture (RPD) wearers and non‐wearers using cone‐beam computed tomography (CBCT). Materials and Methods: In total, 124 sites in the CBCT scans of 62 (29 RPD non‐wearers, 33 RPD wearers) Kennedy Class II patients were analyzed retrospectively. Three‐dimensional representations of the mandible with superimposed cross‐sectional slices were developed with the CBCT scans to evaluate the mandibular alveolar height and width by measuring distances between the mandibular canal, mylohyoid ridge, alveolar crest, and lower border of the mandible in four regions (eight sites) of Kennedy Class II non‐wearers and wearers of RPDs. Results: Mandibular alveolar bone height and width were significantly lower in edentulous sites when compared with dentate sites in both Kennedy Class II non‐wearers and wearers of RPDs (p < 0.05). Additionally, mean vertical and horizontal mandibular bone resorption was significantly higher in RPD wearers than in non‐wearers (p < 0.05). Conclusions: Vertical and horizontal alveolar bone resorption was found to be higher in the RPD wearing patients when comparing the dentate and edentulous sites. 相似文献
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Berna Akkus Yildirim Yemliha Dolek Ozan Cem Guler Gungor Arslan Cem Onal 《Medical Dosimetry》2019,44(4):332-338
We performed this dosimetric study to compare a nonstandard volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT) techniques with high-dose rate (HDR) brachytherapy (BRT) plan of vaginal vault in patients with postoperative endometrial cancer (EC). Twelve postoperative patients with early stage EC were included in this study. Three plans were performed for each patient; dosimetric and radiobiological comparisons were made using dose-volume histograms and equivalent dose for determining the planning target volume (PTV) coverages in brachytherapy and external beam radiotherapy, and organs-at-risk (OARs) doses between three different delivery techniques. All the plans achieved adequate dose coverage for PTV; however, the VMAT plan yielded better dose conformity, and the HT plan showed better homogeneity for target volume. With respect to the OARs, the bladder D2cc was significantly lower in the BRT plan than in the VMAT and HT plans, with the highest bladder D2cc value being observed in the HT plan. However, no difference was observed in the rectum D2cc of the three plans. Other major advantages of the BRT plan over the VMAT and HT plans were the relatively lower body integral doses and femoral head doses as well as the fact that the integral doses were significantly lower in the BRT plan than in the VMAT and HT plans. This is the first dosimetric comparison of vaginal vault treatment for EC with BRT, VMAT, and HT plans. Our analyses showed the feasibility of stereotactic body radiotherapy technique as an alternative to HDR-BRT for postoperative management of EC patients. 相似文献
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Patzig Maximilian Forbrig Robert Küpper Clemens Eren Ozan Saam Tobias Kellert Lars Liebig Thomas Schöberl Florian 《Journal of neurology》2022,269(2):982-996
Journal of Neurology - To approach the clinical value of MRI with vessel wall imaging (VWI) in patients with central nervous system vasculitis (CNSV), we analyzed patterns of VWI findings both at... 相似文献
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Ghrelin is a recently discovered hormone secreted by cells of the stomach. The aim of this study was to investigate fasting and refeeding induced alterations on ghrelin immunolabelling of cells of the stomach. Thirty-six adult male Wistar rats were used in this study. Rats were divided into six groups. Group I: control group; Group II: rats fasted for 7 days; Group III: rats fed for 1 day after 7 days of fasting; Group IV: rats fed for 3 days after 7 days of fasting; Group V: rats fed for 5 days after 7 days of fasting; Group VI: rats fed for 7 days after 7 days of fasting. At the end of the experiment, rats were sacrificed and stomach tissues were processed for imunohistochemistry to localize ghrelin. Ghrelin-immunopositive cells were detected only in the mucosal lining of the stomach. After fasting for 7 days, the number of ghrelin-immunopositive cells increased significantly compared to the control rats. Following refeeding, the number of ghrelin-immunoreactive cells was reduced to a level comparable to the controls. Therefore, fasting and refeeding after fasting were observed to result in changes in ghrelin immunoreactivity in the cells of the stomach. We conclude that ghrelin is highly expressed in the stomach and that fasting increases the expression of ghrelin in the stomach, but this expression decreases after refeeding. Our results indicate that regulation of ghrelin is a process probably involved in the long-term control of nutritional states. 相似文献
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AIM: The aim of this study was to evaluate the prevalence of signs and symptoms of temporomandibular disorders (TMD) in a population of 792 Turkish adults ranging in age from 15- to 72-years-old. METHODS AND MATERIALS: Subjects were examined objectively and subjectively for signs and symptoms of TMD through the distribution of frequency of the data obtained from a questionnaire and a physical examination using a similar methodology of previous studies. RESULTS: This study determined the prevalence of signs and symptoms of TMDs in subjects from male and female subgroups in a Turkish adult population. Both signs and symptoms of TMDs were generally more prevalent in females than in males. CONCLUSION: The prevalence of signs and symptoms were generally greater than in previous studies of other populations. 相似文献
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Gandham Lakshminarayana Youssef Elmahroug Ashok Kumar Huseyin Ozan Tekin Najeh Rekik Mengge Dong Dong-Eun Lee Jonghun Yoon Taejoon Park 《Materials》2021,14(9)
For both the B2O3-Bi2O3-CaO and B2O3-Bi2O3-SrO glass systems, γ-ray and neutron attenuation qualities were evaluated. Utilizing the Phy-X/PSD program, within the 0.015–15 MeV energy range, linear attenuation coefficients (µ) and mass attenuation coefficients (μ/ρ) were calculated, and the attained μ/ρ quantities match well with respective simulation results computed by MCNPX, Geant4, and Penelope codes. Instead of B2O3/CaO or B2O3/SrO, the Bi2O3 addition causes improved γ-ray shielding competence, i.e., rise in effective atomic number (Zeff) and a fall in half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP). Exposure buildup factors (EBFs) and energy absorption buildup factors (EABFs) were derived using a geometric progression (G–P) fitting approach at 1–40 mfp penetration depths (PDs), within the 0.015–15 MeV range. Computed radiation protection efficiency (RPE) values confirm their excellent capacity for lower energy photons shielding. Comparably greater density (7.59 g/cm3), larger μ, μ/ρ, Zeff, equivalent atomic number (Zeq), and RPE, with the lowest HVL, TVL, MFP, EBFs, and EABFs derived for 30B2O3-60Bi2O3-10SrO (mol%) glass suggest it as an excellent γ-ray attenuator. Additionally, 30B2O3-60Bi2O3-10SrO (mol%) glass holds a commensurably bigger macroscopic removal cross-section for fast neutrons (ΣR) (=0.1199 cm−1), obtained by applying Phy-X/PSD for fast neutrons shielding, owing to the presence of larger wt% of ‘Bi’ (80.6813 wt%) and moderate ‘B’ (2.0869 wt%) elements in it. 70B2O3-5Bi2O3-25CaO (mol%) sample (B: 17.5887 wt%, Bi: 24.2855 wt%, Ca: 11.6436 wt%, and O: 46.4821 wt%) shows high potentiality for thermal or slow neutrons and intermediate energy neutrons capture or absorption due to comprised high wt% of ‘B’ element in it. 相似文献
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Parag Goyal Ozan Unlu Peter J. Kennel Ross C. Schumacher Lauren G. Gilstrap Ashok Krishnaswami Larry A. Allen Mathew S. Maurer Michael W. Rich Anil Makam 《Journal of cardiac failure》2021,27(2):190-197
BackgroundTo facilitate evidence-based medicine (EBM) on an individual level, it may be important for clinical practice guidelines (CPGs) to incorporate the performance parameters of diagnostic studies and therapeutic interventions (such as likelihood ratio and absolute benefit or harm), and to incorporate relevant patient contexts that may influence decision-making. We sought to determine the extent to which heart failure CPGs currently incorporate this information.MethodsWe reviewed the American College of Cardiology Foundation/American Heart Association (ACCF/AHA) 2013 Heart Failure CPG, the 2017 ACCF/AHA/HFSA update, and European Society of Cardiology (ESC) 2016 Heart Failure CPG. We abstracted variables for each CPG recommendation from the following domains: quality of evidence, strength of recommendation, diagnostic and therapeutic performance parameters, and patient context.ResultsWe examined 169 recommendations from the ACCF/AHA 2013 CPGs and 2017 update and 187 recommendations from the 2016 ESC CPGs. Performance parameters for diagnostic studies (2013 ACCF/AHA: 13%; 2017 ACCF/AHA/HFSA update: 0%; 2016 ESC: 0%) and therapeutic interventions (2013 ACCF/AHA: 65%; 2017 ACCF/AHA/HFSA update: 64%; 2016 ESC: 16%) were not commonly included in CPGs. Patient context was included in about half of ACCF/AHA recommendations and a quarter of ESC recommendations.ConclusionsThe majority of recommendations from heart failure CPGs lack information on diagnostic and therapeutic performance parameters and patient context. Given the importance of these components to effectively implement EBM, particularly for a heterogeneous heart failure population, innovative strategies are needed to optimize CPGs so they provide comprehensive yet succinct recommendations that can improve population-level outcomes and ensure optimal patient-centered care. 相似文献