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Öğe COMBINING ABILITIES OF GRAIN YIELD AND YIELD RELATED TRAITS IN RELATION TO DROUGHT TOLERANCE IN TEMPERATE MAIZE BREEDING(SOC FIELD CROP SCI, 2015) Erdal, Sekip; Pamukcu, Mehmet; Ozturk, Ahmet; Aydinsakir, Koksal; Soylu, SuleymanTemperate maize growing regions are increasingly prone to drought stress which is emerging as a primary constraint to maize productivity. Introgression of tropical sources of drought tolerance into temperate maize breeding may contribute to improving the drought tolerance of the relatively narrow temperate germplasm base that is currently in use. In the present study, seven tropical drought tolerant inbred lines and two well-adapted commercial temperate inbred lines were crossed in a half-diallel design. The 9 parents, 36 diallel hybrids and 2 commercial checks were tested in well-watered and managed water stressed conditions in Antalya, Turkey in 2013 and 2014. Significant differences were detected between genotypes for number of days to anthesis, anthesis-silking interval, plant height, thousand kernel weight, number of ears per plant, number of kernels per ear and grain yield. Tropical inbreds G1 and G5 were comparable to the adapted temperate commercial inbreds in terms of general combining ability. Specific combining ability analysis revealed that tropical x temperate hybrids had higher values compared to tropical x tropical hybrids. Yield potential of hybrid G5 x G9 in particular, a promising tropical x temperate hybrid, was significantly higher under both well watered and drought conditions. Our results suggest that tropical drought tolerant germplasm is likely to have high utility in temperate maize breeding programs.Öğe Epidemiologic survey: reference ranges of serum insulin-like growth factor 1 levels in Caucasian adult population with immunoradiometric assay(SPRINGER, 2011) Bayram, Fahri; Gedik, Vedia Tonyukuk; Demir, Ozgur; Kaya, Ahmet; Gundogan, Kursat; Emral, Rifat; Ozturk, AhmetGender, age adjusted, population based reference ranges are necessary to use insulin-like growth factor 1 (IGF-1) as a diagnostic marker or for therapeutic monitoring in growth hormone (GH) related diseases. The aim of the present study was to describe the serum IGF-1 distribution and to calculate age and gender specific reference values for Caucasian adult population. A representative sample of 1002 male and 1039 female, totally 2041 participants aged above 18 years old was examined. The subjects suffering from diabetes mellitus, renal diseases, liver diseases, cancer, or diseases of pituitary gland were excluded by medical history, physical examination, and laboratory tests. The subjects were not using any drug that could affect IGF-1 levels. Body mass index (BMI) >30 or <18 kg/m(2) were excluded. Serum IGF-1 concentrations were determined by immunoradiometric assay (IRMA). Serum IGF-1 concentrations were declined with age in both males and females after the age of 18. Males had significantly higher serum IGF-1 levels than females in the age groups 18-24, 50-69 (P < 0.05), but not in others (P > 0.05). The present study established age and gender specific reference ranges for serum IGF-1 levels calculated for Caucasian adult population with IRMA that could be used in medical practice.Öğe Factors Affecting Complication Rates of Percutaneous Nephrolithotomy in Children: Results of a Multi-Institutional Retrospective Analysis by the Turkish Pediatric Urology Society(ELSEVIER SCIENCE INC, 2014) Onal, Bulent; Dogan, Hasan Serkan; Satar, Nihat; Bilen, Cenk Y.; Gunes, Ali; Ozden, Ender; Ozturk, AhmetPurpose: We assessed factors affecting complication rates of percutaneous nephrolithotomy in children. Materials and Methods: We retrospectively evaluated data on 1,205 renal units in 1,157 children treated with percutaneous nephrolithotomy at 16 Turkish centers between 1991 and 2012. Of the patients 28.3% had a history of urolithiasis. Complications were evaluated according to the Satava classification system and modified Clavien grading system. Univariate and multivariate analyses were done to determine predictive factors affecting complication rates. Results: A total of 515 females and 642 males were studied. Mean +/- SD patient age was 8.8 +/- 4.7 years (range 4 months to 17 years). Mean +/- SD stone size, operative time and postoperative hospital stay were 4.09 +/- 4.06 cm 2, 93.5 +/- 48.6 minutes and 5.1 +/- 3.3 days, respectively. Postoperative stone-free rate was 81.6%. A total of 359 complications occurred in 334 renal units (27.7%). Complications were intraoperative in 118 cases and postoperative in 241. While univariate analysis revealed that stone history, positive urine culture, operative time, length of hospitalization, treatment success, punctured calyx and location of the stone significantly affected the complication rates (p <0.05), operative time, sheath size, mid calyceal puncture and partial staghorn formation were the statistically significant parameters affecting complication rates on multivariate logistic regression analysis. Conclusions: Percutaneous nephrolithotomy is the treatment of choice for most renal calculi in children. The technique is effective and safe in children, with a high success rate and a low rate of major complications. The significant factors identified should be considered by clinicians to decrease associated complication rates.Öğe Penis replantation after self-mutilation(SPRINGER, 2009) Ozturk, Ahmet; Kilinc, Mehmet; Guven, Selcuk; Gormus, Niyazi; Belviranli, Metin; Kaynar, Mehmet; Arslan, MehmetIn this case report, the procedure of penis replanting and its complications after genital self-mutilation in a male adult are explained.Öğe Simultaneous Bilateral Percutaneous Nephrolithotomy in Children: No Need to Delay(MARY ANN LIEBERT INC, 2011) Guven, Selcuk; Ozturk, Ahmet; Arslan, Mehmet; Istanbulluoglu, Okan; Piskin, Mesut; Kilinc, MehmetBackground and Purpose: Children with bilateral kidney stones are generally treated using staged percutaneous nephrolithotomy (PCNL). Reports related to simultaneous bilateral PCNL (SBPCNL) in children are scarce. We aimed to evaluate the efficacy and safety of SBPCNL in children. Patients and Methods: The children who underwent SBPCNL applications between January 2007 and February 2010 in our clinic were evaluated. Patient data were collected from the retrospective reviews of hospital records. Results: SBPCNL was conducted in five patients for bilateral renal stones. The mean age of the patients was 6.28 years (range 0.75-15 y), and the mean follow-up was 10.6 months (range 1-36 mos). The mean renal stone burden was 19 mm (range 11-22 mm). Four children underwent bilateral standard PCNL, and one child underwent bilateral tubeless PCNL. The mean duration of SBPCNL was 75 minutes (range 55-120 min), and the hospitalization time was 4 days (range 2-5 d). No blood transfusion was necessary in any patient. Except for the patient with complex renal stones, all patients were stone free after the intervention, and none needed a conversion to open surgery. Conclusion: SBPCNL is a safe and effective procedure in children if they are selected properly and if the surgeon has sufficient experience with the procedure. More studies with a higher number of participants are needed, however, for further evaluation of the procedure.Öğe Successful Percutaneous Nephrolithotomy in Children: Multicenter Study on Current Status of its Use, Efficacy and Complications Using Clavien Classification(ELSEVIER SCIENCE INC, 2011) Guven, Selcuk; Istanbulluoglu, Okan; Gul, Umit; Ozturk, Ahmet; Celik, Huseyin; Aygun, Cem; Ozdemir, UmitPurpose: In this multicenter study we aimed to evaluate the efficacy and safety of percutaneous nephrolithotomy in children with respect to different features and using the Clavien classification system. Materials and Methods: Percutaneous nephrolithotomies performed in children at 3 urology departments between March 2006 and May 2010 were included in the study. Results are presented for complex/simple renal stones, tubeless/totally tubeless percutaneous nephrolithotomy, simultaneous bilateral percutaneous nephrolithotomy, instrument size and age groups. Patients were divided into 3 distinct groups, infants and toddlers (3 years or younger, group 1), preschool children (4 to 7 years, group 2) and school children (8 to 16 years, group 3). Perioperative complications are presented according to the modified Clavien classification system. Results: A total of 140 percutaneous nephrolithotomies were performed in 130 patients (41.5% female, mean age 10.17 years). There were 23, 25 and 92 renal units in groups 1, 2 and 3, respectively. Pediatric instruments were used in 60 renal units and adult-sized instruments in 80. General assessment of complications showed Clavien grade I complications in 17 patients, II in 4, IIIa in 11 and IIIb in 7. There were no grade IV or V complications. Conclusions: Percutaneous nephrolithotomy can be applied safely in children of varying ages, even infants. Complications, as assessed with Clavien classification, are comparable to those seen in adults provided there is enough experience with the technique.Öğe Totally Tubeless Percutaneous Nephrolithotomy: Is It Safe and Effective in Preschool Children?(MARY ANN LIEBERT, INC, 2010) Ozturk, Ahmet; Guven, Selcuk; Kilinc, Mehmet; Topbas, Emrah; Piskin, Mesut; Arslan, MehmetBackground and Purpose: After the introduction of tubeless percutaneous nephrolithotomy (PNL), many studies conducted in adult patients have confirmed its efficacy and safety. There are limited studies reporting that tubeless PNL can be safely applied in children, however. Furthermore, there are no reports that evaluate the use of totally tubeless PNL in children. The present study evaluates the results of totally tubeless PNL in preschool children. Patients and Methods: The data of children seen in our clinic who were considered suitable for totally tubeless PNL were analyzed. Of 16 children, 8 patients underwent totally tubeless PNL (group 1) and 8 standard PNL (group 2). The two groups of patients were compared with regard to length of hospitalization, analgesic requirements, transfusion rates, hemoglobin (Hb) decrease, and immediate, early, and late complications. Results: The mean ages of the patients were 56.6 months (9-84 mos) and 56.0 months (5-84 mos), and the mean follow-up was 21.5 months (3-44 mos) and 43.4 months (36-54 mos) in groups 1 and 2, respectively. Both groups were similar with regard to age, stone size, Hb change, and complications. Although operation duration, hospitalization period, and analgesic requirement were less in the totally tubeless PNL group, these differences were not statistically significant. Conclusions: The latest application of PNL, totally tubeless PNL, is also a safe and effective procedure in very small children if they are selected properly and if the surgeon has sufficient experience with the procedure. More studies with a higher number of participants are needed, however, to confirm that totally tubeless PNL increases the comfort of pediatric patients, decreases their hospitalization period, and is more economical.Öğe Treatment of complete urethral obstruction by using pneumatic lithotripsy in a dog: A preliminary report(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2016) Maden, Mehmet; Ider, Merve; Parlak, Kurtulus; Ozturk, AhmetIn this preliminary case presentation, use of the minimally invasive cystoscopic pneumatic lithotripsy technique in the treatment of complete urethral obstruction in a dog has been described. The animal of the case comprised a 5-year old Chihuahua presenting with difficulty during urination and inability to urinate for the previous 2 days. Post-renal azotemia and hematuria was determined. Urethral stones causing complete urethral obstruction were visualized via cystoscopy, fragmented with a pneumatic lithotripter and the stone fragments were removed using the voiding urohydropulsion method. In conclusion, the pneumatic lithotripsy method was successfully used in the treatment of complete urethral obstruction.
