TR-Dizin Açık Erişimli Yayınlar

Permanent URI for this collectionhttps://hdl.handle.net/11727/10759

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    Clinicohistopathological Features and Treatment Outcomes of Neuroendocrine Tumors; A Single Center Experience
    (2017) Sumbul, A. T.; Sedef, A. M.; Kose, F.; Mertsoylu, H.; Sezer, A.; Ozyilkan, O.; Abali, H.; https://orcid.org/0000-0002-5573-906X; https://orcid.org/0000-0001-8825-4918; D-4793-2014; AAD-2817-2021
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    The prognostic value of mean apparent diffusion coefficient measured with diffusion-weighted magnetic resonance image in patients with prostate cancer treated with definitive radiotherapy
    (2022) Onal, Cem; Erbay, Gurcan; Guler, Ozan Cem; Oymak, Ezgi; 35753556
    Purpose: To assess the correlation between initial tumor apparent diffusion coefficient (ADC) values and clinicopathological parameters in prostate cancer (PCa) patients treated with definitive radiotherapy (RT). Additionally, the prognostic factors for freedom from biochemical failure (FFBF) and progressionfree survival (PFS) in this patient cohort were analyzed. Materials and methods: The clinical data of 503 patients with biopsy-confirmed PCa were evaluated retrospectively. All patients had clearly evident tumors on diffusion-weighted magnetic resonance imaging (DW-MRI) for ADC values. Univariable and multivariable analyses were used to determine prognostic factors for FFBF and PFS. Results: The median follow-up was 72.9 months. The 5-year FFBF and PFS rates were 93.2% and 86.2%, respectively. Significantly lower ADC values were found in patients with a high PSA level; advanced clinical stage; higher ISUP score, and higher risk group than their counterparts. Receiver operating characteristic (ROC) curve analysis revealed an ADC cut-off value of 0.737 x 10-3 mm2/sec for tumor recurrence. Patients who progressed had a lower mean ADC value than those who did not (0.712 +/- 0.158 vs. 1.365 +/- 0. 227 x 10-3 mm2/sec; p < 0.001). There was a significant difference in 5-year FFBF (96.3% vs. 90%; p < 0.001) and PFS rates (83.8% vs. 73.5%; p = 0.002) between patients with higher and lower mean ADC values. The FFBF and PFS were found to be correlated with tumor ADC value and ISUP grades in multivariable analysis. Additionally, older age was found to be a significant predictor of worse PFS. Conclusions: Lower ADC values were found in patients with high-risk characteristics such as a high serum PSA level, stage or grade of tumor, or high-risk disease, implying that ADC values could be used to predict prognosis. Lower ADC values and higher ISUP grades were associated with an increased risk of BF and progression, implying that treatment intensification may be required in these patients. (c) 2022 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 173 (2022) 285-291
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    Validity and Reliability Evidence of Professional Obsolescence Scale According to Different Test Theories
    (2021) Altun, Sedagul Akbaba; Buyukorturk, Sener; Seheryeli, Merve Yildirim
    This study aims to develop a scale that will determine the factors causing professional obsolescence in the field of education. In this context, the Professional Obsolescence Scale (POS) has been developed to determine the professional and organizational obsolescence of primary, secondary and high school administrators. In this scale development process, steps were followed in line with the suggestions of Crocker and Algina (2006) and Cronbach (1984). Firstly, 63 items were prepared and 991 school principals participated the study. R (version 4.0.1) software was used to analyze the data. Item and test parameters and information functions have been estimated using Samejima's Graded Response Model based on Item Response Theory. Principal Axis Analysis was performed for the construct validity of the scale, and four-dimensions structure with 47 items has been obtained. These dimensions are named as "Being Open to Professional Development", "Job-Ability Harmony in Profession", "Organizational Support in Professional Development", "Professional Burnout". The scores obtained from each dimension are evaluated within themselves. It has been observed that each dimension fulfills the conditions of unidimensionality, local independence, model-data fit and parameter invariance. According to the Classical Test Theory, Cronbach Alpha coefficients are between 0.807 and 0.945. The Stratified Alpha coefficient calculated for the whole scale is 0.94. According to the Item Response Theory, the marginal reliability coefficients were between 0.857 and 0.936 and the empirical reliability coefficients were found between 0.854 and 0.938.
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    Early Maxillary Expansion with the Ni-Ti Memory Leaf Expander-A Compliance-Free Fixed Slow Maxillary Expansion Screw: A Report of 2 Cases
    (2021) Ulug, Bahar; Ozcirpici, Ayca Arman; 35110164
    Transversal problems such as crowding and crossbite are one of the most common problems dealt with in early orthodontic treatments. Early correction of these problems may ease or even eliminate the future need for treatment. This paper presents the management of 2 cases with transverse discrepancy using the Ni-Ti Memory Leaf Expander-a new compliance-free slow maxillary expansion appliance. The total treatment time for both cases was 9 months. In both cases, the inter-canine, inter-premolar, and inter-molar distances, as well as the arch length, have all increased.
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    Do Hemodialysis Patients Need Immune Boosting with Vitamin, Mineral, and Probiotic Supplementation during COVID-19 Pandemic?
    (2021) Gungor, Ozkan; Ulu, Sena; Hasbal, Nuri Baris; Onan, Engin; Turgut, Didem; Arici, Mustafa
    Coronavirus disease 2019 (COVID-19) has been accepted as a global pandemic, and poses a greater risk to the elderly and those with comorbidities. Comorbid diseases (particularly end-stage kidney disease with hemodialysis) and impaired immunity place patients in the high-risk group for COVID-19. In recent studies, it was also mentioned that exaggerated inflammation and a cytokine storm were the underlying causes related to the high mortality in COVID-19 patients. Currently, treatment modalities to balance the immune system of such vulnerable patient groups are essential, to protect them from the disease. Several vitamins (like vitamins C, D, and E), trace elements like zinc, and probiotics have been proposed as immune boosters to protect and combat infectious conditions. It is well known that these vitamins and elements are insufficient in hemodialysis patients. In this review, we aimed to evaluate the immune-boosting mechanisms of vitamins C, D, E, zinc, and probiotics, the studies related to their beneficial effects against infections, and their possible benefits for hemodialysis patients during the COVID-19 pandemic.