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71.
72.
Fatma Yildiztekin Ebru Erol Mahmut Yildiztekin Atilla L. Tuna Mehmet Ozturk 《Pharmaceutical biology》2016,54(9):1557-1563
Context We report the first ever chemical/biochemical study on Crocus mathewii Kerndorff (Iridaceae) – a Turkish endemic angiosperm. This plant has never been explored for its phytochemistry and bioactivities.Objective This study explores C. mathewii corm and aerial parts for the chemical and biological properties of hexane, ethyl acetate, methanol and water fractions of the extracts.Material and methods Plant material (20 g) was extracted by methanol (250?mL?×?5, 3 days each) and fractioned into hexane, ethyl acetate, methanol and water. All fractions were subjected to β-carotene–linoleic acid, DPPH·, ABTS·+, CUPRAC, metal chelating and tyrosinase inhibition activities. Hexane fractions were submitted to GC–MS analysis.Results Ethyl acetate fractions showed excellent IC50 values in DPPH· (aerial 36.21?±?0.76 and corm 33.87?±?0.02?mg/L) and ABTS·+ (aerial 33.01?±?0.79 and bulb 27.87?±?0.33?mg/L); higher than the IC50 of the standard α-tocopherol (DPPH 116.25?±?1.97; ABTS 52.64?±?0.37?mg/L), higher than BHA in DPPH (57.31?±?0.25?mg/L), but slightly lower in ABTS (19.86?±?2.73?mg/L). Methanol extract of aerial parts also showed higher activity than α-tocopherol in DPPH (85.56?±?11.51?mg/L) but slightly less (72.90?±?3.66?mg/L) than both the standards in ABTS. Linoleic (aerial 53.9%, corm 43.9%) and palmitic (aerial 22.2%, corm 18%) were found as the major fatty acids.Discussion and conclusion Some fractions of C. mathewii showed higher antioxidant activities than the standards. There is a need to explore more about this plant. 相似文献
73.
Selim Kurtoglu Mehmet Emre Atabek Ceyhun Dizdarer Ozgur Pirgon Pinar Isguven Sevil Emek 《Pediatric diabetes》2009,10(6):401-407
Background: Insulin detemir is a basal insulin analog designed to produce a superior pharmacokinetic profile to basal formulations of human insulin. It has shown consistently improved tolerability in comparison to neutral protamine Hagedorn (NPH) insulin in adult cohorts, but there are relatively few publications involving pediatric cohorts. Methods: The efficacy and safety of insulin detemir in children with type 1 diabetes was assessed using data from the Turkish cohort of PREDICTIVE? (a large, multinational, observational) study. The children investigated were using basal–bolus therapy involving NPH insulin or insulin glargine at baseline but were switched to insulin detemir as part of routine clinical care by their physicians. Results: Twelve weeks of treatment with insulin detemir significantly reduced mean hemoglobin A1c (9.7–8.9%, p < 0.001) and mean fasting glucose [185–162 mg/dL (10.3–9 mmol/L), p < 0.01]. Fasting glucose variability was also lower after treatment with insulin detemir than previously (on either NPH or glargine, p < 0.05). The frequencies of total, major and nocturnal hypoglycemic events were significantly reduced with insulin detemir relative to baseline, with an estimated mean of 6.89 fewer events/patient/yr overall (p < 0.001) and 2.6 fewer nocturnal events/patient/yr (p < 0.01). Weight and insulin dose remained relatively unchanged. Conclusions: Twelve weeks of treatment with insulin detemir improved glycemic control and reduced hypoglycemia in children with type 1 diabetes. This improved tolerability might allow further dose titration and therefore additional improvements in glucose control. 相似文献
74.
Mehmet Tetikoğlu Serdar Aktas Hacı Murat Sagdık Sıla Tasdemir Yigitoglu Fatih Özcura 《Seminars in ophthalmology》2017,32(5):651-654
Aim: To evaluate the effect of the platelet indices on the stage of diabetic retinopathy (DR) and diabetic macular edema (DME). Methods: In this retrospective study, the mean platelet valume (MPV), Plateletcrit (PCT), platelet (PLT), and platelet distribution width (PDW) of 199 diabetic patients and 76 healthy subjects were enrolled. The participants were divided into four groups. The first group was healthy control; the second group consisted of diabetic patients without DR; the third group was nonproliferative DR (NPDR); and the fourth group was proliferative DR (PDR). Results: Significant differences were found only in MPV and PCT values between patients with diabetes and healthy participants (8.6±0.96 fL vs 8.32±0.9 fL, P=0.011, 0.216± 0.58 vs 0.202±0.52, P=0.038). Comparing the groups, a statistically significant difference in MPV values was found between groups 4 and 1 (8.91±.7 fL vs 8.32±0.9 fL P=0.001) and between groups 4 and 3 (8.91±.7 fL vs 8.42±0.9 fL P=0.014). The MPV values of patients with DME were significantly higher than those of diabetic patients without DME (8.87±0.80 fL vs 8.45±0.97 fL). Conclusion: High MPV values may be an important risk factor for the development of PDR and DME in patients with diabetic retinopathy. 相似文献
75.
Eren Erdogdu Berker Ozkan Salih Duman Melek Agkoc Sukru Mehmet Erturk Murat Kara Alper Toker 《The clinical respiratory journal》2022,16(5):361
BackgroundThe management of a solitary pulmonary nodule is a challenging issue in pulmonary disease. Although many factors have been defined as predictors for malignancy in solitary pulmonary nodules, the accurate diagnosis can only be established with the permanent histological diagnosis.ObjectiveWe tried to clarify the possible predictors of malignancy in solitary pulmonary nodules in patients who had definitive histological diagnosis.MethodsWe made a retrospective study to collect the data of patients with solitary pulmonary nodules who had histological diagnosis either before or after surgery. We made a statistical analysis of both the clinic and radiological features of these nodules with respect to malignancy both in contingency tables and with logistic regression analysis.ResultsWe had a total of 223 patients with a radiological diagnosis of solitary pulmonary nodule. Age, smoking status and pack years of smoking, maximum standardized uptake value (SUVmax), and radiological features such as solid component, spiculation, pleural tag, lobulation, calcification, and higher density were significant predictors of malignancy in contingency tables. Age, smoking status and smoking (pack/year), SUVmax, and radiological features including spiculation, pleural tag, lobulation, calcification, and higher density were the significant predictors in univariate analysis. However, multivariate analysis revealed only SUVmax greater than 2.5 (p < 0.0001), spiculation (p = 0.009), and age older than 61 years (p = 0.015) as the significant predictors for malignancy.ConclusionAge, SUVmax, and spiculation are the independent predictors of malignancy in patients with solitary pulmonary nodules. 相似文献
76.
Mohamad Alhajhamoud Sayit Ozbey Mehmet Alp Ilgaz Levent Candan Ibrahim Cinar Mario Vukoti Selma orovi Damijan Miljavec Ersin Kayahan 《Materials》2022,15(24)
Ti6Al4V titanium alloys are widely used in a variety of scientific and industrial fields. Laser beam welding is one of the most effective techniques for the joining of titanium plates. The main objective of this study was to investigate the influence of the most important laser parameters on welding performance of titanium alloy in two different physical environments such as air and water (i.e., serum) media. Specifically, the laser beam welding of 2 mm thick Ti6Al4V samples was applied using an Nd:YAG laser in open-air welding using argon as a shielding gas, and in wet welding using a serum environment. The deepest penetration was achieved at −3 mm focal position with 11 J of laser energy in both investigated media (i.e., air and serum). The maximum hardness (1130 HV) was achieved for the focal position of −4 mm in serum medium while it was 795 HV for a focal position of −5 mm in air medium. The minimum (1200 μm and 800 μm) and maximum (1960 μm and 1900 μm) weld widths were observed for air and serum medium, respectively. After the welding process, martensite, massif martensite, and transformed martensite were observed in the microstructure of Ti6Al4V. To the best of our knowledge, the underwater wet welding of titanium alloy was carried out and reported for the first time in this study. 相似文献
77.
Mehmet I. Buget Nur Canbolat Chasan M. Chousein Taha Kizilkurt Ali Ersen Kemalettin Koltka 《Medicine》2022,101(27)
Supracondylar humeral fractures are seen in children and treatment is usually closed reduction and percutaneous pinning (CRPP). This surgery can be performed at night, depending on its urgency. Fatigue and sleep deprivation can impact performance of doctors during night shifts. The purpose of this study is to investigate the association between night shifts postoperative morbidity and mortality of supracondylar fracture operations compared to daytime procedures.This prospective observational study included 94 patients who were aged 5 to 12 years with ASA I to III who had supracondylar humeral fractures, underwent CRPP under general anesthesia. Patients were stratified by the time of surgery using time of induction of anesthesia as the starting time of the procedure, into 2 groups: day (07:30 am–06:29 pm) and night (06:30 pm–07:29 am). In total, 82 patients completed the study: 43 in Group Day and 39 in Group Night.The operation duration in Group Night (114.66 ± 29.46 minutes) was significantly longer than in Group Day (84.32 ± 25.9 minutes) (P = .0001). Operation duration (OR: 0.007; P = .0001) and morbidities (OR: 0.417; P = .035) were independent risk factors in Group Night.Children who had supracondylar humeral fractures, undergoing urgent CRPP surgery, in-hospital mortality was associated with the time of day at which the procedure was performed. Patient safety is critically important for pediatric traumatic patient population. Therefore, we suggested to increase the number of healthcare workers and improve the education and experience of young doctors during night shifts. 相似文献
78.
Ünzüle Korkmaz
zer Birge Mehmet Sait Bakr Saliha San Tayup Simsek 《International journal of clinical and experimental pathology》2022,15(7):289
Ovarian torsion refers to partial or complete rotation of the ovary on its ligamentous support, often resulting in partial or complete obstruction of its blood supply. It is one of the most common gynecologic surgical emergencies and may affect females of all ages, but it is relatively rare in postmenopausal women. Chronic adnexal torsion with complete occlusion of the ovarian blood supply results in necrosis and loss of ovarian function. Clinical symptoms and signs are not specific and definitive diagnosis is often challenging. In this case report, we present a 65-year-old woman with chronic ovarian torsion that was detected 7 years after vaginal hysterectomy. Approximately 3% of postmenopausal cases with adnexal torsion are associated with malignancy. Ovarian torsion incidence is low in postmenopausal ovarian cancer due to the progression of accompanying inflammation, which causes immobility of the ovarian mass. 相似文献
79.
Alper Kurtoglu Alauddin Kochai Mustafa Erkan Inanmaz Erhan Sukur Dogan Keskin Mehmet Türker Mustafa Uysal Zafer Sen Ismail Daldal 《Medicine》2021,100(13)
Different methods have been used throughout the years for syndesmotic injury but there is no consensus on the ideal treatment. Some methods are expensive and some have more complications. The aim of this study is to compare single suture endobutton with double suture endobutton and screw fixation for syndesmotic injury.Sixty nine patients with syndesmotic injury with fibular fractures whom were treated with a single interosseous suture endobutton system (ZipTightTM, Zimmer Biomet), a double interosseous suture endobutton system (ZipTightTM, Zimmer Biomet) and 1 syndesmotic screw (TST, Istanbul, Turkey) were included in this study. Functional and radiological results from patient records between 2015 and 2018 were retrospectively evaluated.Twenty patients were treated with the double interosseous suture endobutton, 23 were treated with the single interosseous suture endobutton, and 26 were treated with traditional AO screw fixation. Three patients from the screw fixation group (11.5%) required revision surgery (P < .05). All the radiologic and clinical outcomes were statistical similar in all 3 groups.Our findings showed that the interosseous suture endobutton system is at least as safe as the screw fixation technique for treatment of syndesmosis joint injuries and can be used as an alternative to the screw method. The interosseous suture endobutton system eliminates the need for a second surgery to remove the hardware, which minimizes the probability of re-diastasis. Since our results showed no statistical difference between single and double interosseous suture endobutton systems, the less costly single endobutton system may be the better alternative. 相似文献
80.
Koygun Gozde Kayadibi Kars Meltem Demirel Emsen Ayca Artac Hasibe Aksoy Faruk Cakir Murat Tavli Lema Artac Mehmet 《Clinical and experimental medicine》2021,21(3):447-456
Clinical and Experimental Medicine - Breast cancer (BC) is the leading cause of cancer deaths in women. One of the reasons for the failure of BC treatment is reportedly the ineffectiveness of... 相似文献