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81.
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
82.
I. Aktas C. Nazikoglu A. Kepez F. U. Ozkan M. Y. Kaysin P. Akpinar Z. Dogan C. Ileri S. Saymaz O. Erdogan 《Osteoporosis international》2016,27(12):3543-3547
Summary
We evaluated the effects of zoledronic acid (ZA) therapy on electrocardiographic (ECG) parameters for the first time in the literature. Measurements were performed on ECGs obtained before and after ZA infusion on the same day as well as 1 month after the infusion. ZA infusion did not have any short- or long-term effect on any parameter that might be associated with the tendency for atrial fibrillation or ventricular arrhythmias.Introduction
The aim of the present study was to evaluate the early and late effects of ZA therapy on ECG parameters which might be associated with the tendency for atrial and ventricular arrhythmias.Methods
Consecutive patients with osteoporosis who were admitted to our clinic between December 2013 and December 2014 and who were scheduled to receive ZA infusion constituted our study population. Twelve-lead surface ECGs were obtained from all patients before and after ZA infusion on the same day as well as 1 month after the infusion. All ECG parameters were measured and compared with each other for each patient.Results
Data of 100 patients were used in the analysis (9 male; 70.5 ± 11.6 years of age). There were no significant differences between repeated measurements regarding pmax, pmin, and p dispersion values. QT max and QT min values were significantly increased after infusion; however, there were no significant changes in QT dispersion, Tp-e interval, and Tp-e dispersion values.Conclusions
ZA infusion did not affect P wave dispersion both at the immediate post-infusion period and 1 month after infusion. QT values were significantly increased early after ZA infusion; however, there were no significant differences in parameters reflecting disparity of ventricular recovery times and transmural dispersion of ventricular repolarization. Based on these observations, it may be suggested that ZA infusion did not have any short- or long-term effect on any parameter that might be associated with the tendency for atrial fibrillation or ventricular arrhythmias.83.
84.
A. G. Zebitay M. Tutumlu F. F. Verit G. K. Ilhan E. S. Gungor O. Cetin 《Gynecological endocrinology》2016,32(6):442-445
We aimed to compare ovarian (O), uterine (U) and spiral (S) artery (A) resistance of patients diagnosed as fertile, unexplained infertility (UI) and tubal factor infertility (TFI) in the peri-implantation period and independent from the impact of the treatment. UI (n?=?70), TFI (n?=?75) and fertile (n?=?72) patients’ ovarian, uterine and spiral artery pulsatility index (PI), resistance index (RI) and the endometrial thickness, serum estradiol and progesterone levels were compared. The specificity and sensitivity values were calculated according to determined cutoff values. Both TFI and control groups’ UA PI values were significantly lower than the UI group’s PI values. The highest UA RI values were found in UI group and the lowest values were in the control group. UI and TFI groups’ OA PI/RI values were significantly higher than the control group. Both the control and TFI groups’ SA PI/RI values were significantly lower than UI group’s PI/RI values. UI patients’ uterine and spiral arteries PI values >1.86 and >0.85, RI values >0.80 and >0.53 can be used as a valuable test showing reduced uterine perfusion. Ovarian artery PI values >0.96 and RI values >0.58 can be used as tests showing decreased ovarian perfusion in patients with TFI. In these patients, embryo cryopreservation can be considered. 相似文献
85.
86.
Keles GC Cetinkaya BO Ayas B Isildak I Diraman E Koprulu H Acikgoz G 《Clinical oral investigations》2007,11(4):369-376
The hypothesis, a relationship between gingival tissue platelet activating factor (PAF) levels and healing after periodontal
surgery, was tested by measuring PAF levels in gingival tissues collected from sites that had undergone flap surgery and guided
tissue regeneration (GTR) or flap surgery alone. Using a split-mouth design, 20 intrabony defects were randomly assigned to
treatment with flap surgery and GTR (group 1) or with flap surgery alone (group 2). Gingival tissue samples were obtained
at surgery (baseline) and at 6-month follow-up evaluation visit. One half of each sample was used for analysis of PAF levels
by high-performance liquid chromatography, and the other half of the sample was used for histomorphometric analysis that included
measurements of number and diameter of blood vessels. PAF levels and diameter of blood vessels were significantly decreased
(p < 0.01), and the number of blood vessels was significantly increased (p < 0.05) in both groups after 6 months compared to the baseline values. Postoperative number of blood vessels were significantly
higher in group 1 (p < 0.05), whereas there was no significant difference in postoperative PAF levels between the two groups (p > 0.05). Based on the reported results, it is suggested that a decrease in gingival PAF levels might be found after conventional
and regenerative periodontal surgery. 相似文献
87.
Ozkan Y Akoğlu B Varol A Uçankale M Ozkan YK 《The International journal of prosthodontics》2007,20(3):256-258
A 49-year-old patient presented with an Angle Class III malocclusion with a partially edentulous mandible, as diagnosed by orofacial examination and radiographic and cephalometric analyses. The patient refused orthognathic surgery; therefore, the treatment plan included the preparation of all teeth and fabrication of provisional restorations to reestablish optimal occlusion. To allow for the placement of 3 implants, the edentulous posterior mandibular ridge was improved via alveolar distraction. The patient was recalled 3, 6, 12, and 24 months after prosthodontic treatment. The oral situation was stable and patient satisfaction was reported as high. 相似文献
88.
Cetinkaya BO Keles GC Ayas B Aydin O Kirtiloglu T Acikgoz G 《Clinical oral investigations》2007,11(1):61-68
Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal
defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity
of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments
with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly
assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at
preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured
in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative
12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between
baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects
with bioactive glass compared to the treatment with bioabsorbable membrane. 相似文献
89.
β‐adrenergic Receptor Blocker ICI 118,551 Selectively Increases Intermediate‐Conductance Calcium‐Activated Potassium Channel (IKCa)‐Mediated Relaxations in Rat Main Mesenteric Artery
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Endothelial IKCa and/or SKCa channels play an important role in the control of vascular tone by participating in endothelium‐dependent relaxation. Whether β‐AR antagonists, mainly used in hypertension, affect endothelial KCa channel function is unknown. In this study, we examined the effect of the β2‐AR antagonist and inverse agonist ICI 118,551 on the IKCa/SKCa channel activity by assessing functional relaxation responses to several agonists that stimulate these channels. Mesenteric arterial rings isolated from male Sprague Dawley mounted to organ baths. Acetylcholine elicited IKCa‐ and SKCa‐mediated relaxations that were abolished by TRAM‐34 and apamin, respectively. ICI 118,551, which did not dilate the arteries per se, increased the IKCa‐mediated relaxations, whereas SKCa‐mediated relaxations remained unaltered. Same potentiating effect was also detected on the IKCa‐mediated relaxations to carbachol and A23187, but not to NS309. Neither acetylcholine‐induced nitric oxide‐mediated relaxations nor SNP relaxations changed with ICI 118,551. The PKA inhibitor KT‐5720, the selective β2‐AR agonist salbutamol, the selective β2‐AR antagonist butoxamine, the non‐selective β‐AR antagonist propranolol, and the inverse agonists carvedilol or nadolol failed to affect the IKCa‐mediated relaxations. ICI 118,551‐induced increase was not reversed by salbutamol or propranolol as well. Besides, low potassium‐induced relaxations in endothelium‐removed arteries remained the same in the presence of ICI 118,551. These data demonstrate a previously unrecognized action of ICI 118,551, the ability to potentiate endothelial IKCa channel‐mediated vasodilation, through a mechanism independent of β2‐AR antagonistic or inverse agonistic action. Instead, the enhancement of acetylcholine relaxation seems likely to occur by a mechanism secondary to endothelial calcium increase. 相似文献
90.
Acar Baver Kose Ozkan Unal Melih Turan Adil Kati Yusuf Alper Guler Ferhat 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2020,30(1):163-173
European Journal of Orthopaedic Surgery & Traumatology - This retrospective study aimed to compare the clinical and radiological outcomes of patients who underwent biplane chevron medial... 相似文献