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81.
Dilek Akakin Demir Kiran Naziye Ozkan Mehmet Erşahin Zarife Nigar Ozdemir-Kumral Berrak Yeğen Göksel Şener 《Acta histochemica》2013
Spinal cord injury (SCI) induced oxidative stress affects multiple organ systems including the kidney. We studied the possible protective effects of melatonin on SCI-induced oxidative damage in renal tissues of rats. Wistar albino rats (n = 24) were exposed to SCI and divided into vehicle- or melatonin-treated SCI groups. Melatonin was administred intraperitoneally at a dose of 10 mg/kg for seven days. Renal tissues were investigated by light and electron microscopy. Furthermore, tissue malondialdehyde (MDA) and glutathione (GSH) levels and myeloperoxidase (MPO) and superoxide dismutase (SOD) activities were also determined. In the vehicle-treated SCI group, the renal histology was disturbed compared to controls, whereas the melatonin-treated SCI group showed significantly reduced degeneration of renal tissue as seen by both light and electron microscopy. MDA levels, MPO and SOD activities were increased and GSH levels were decreased in the vehicle-treated SCI group compared to controls. On the other hand, decreased MDA levels and MPO activities and increased GSH levels were observed in the melatonin-treated SCI group compared to vehicle-treated SCI group. These results showed that experimentally induced SCI caused oxidative stress in the rat kidney, whereas melatonin treatment reduced oxidative stress, suggesting that it may be used as a complementary therapy of renal problems occurring following SCI. 相似文献
82.
Xuening Chen Asli Ergun Halil Gevgilili Seher Ozkan Dilhan M. Kalyon Hongjun Wang 《Biomaterials》2013
Bottom-up assembly of osteon-like structures into large tissue constructs represents a promising and practical strategy toward the formation of hierarchical cortical bone. Here, a unique two-step approach, i.e., the combination of electrospinning and twin screw extrusion (TSE) techniques was used to fabricate a microfilament/nanofiber shell–core scaffold that could precisely control the spatial distribution of different types of cells to form vascularized osteon-like structures. The scaffold contained a helical outer shell consisting of porous microfilament coils of polycaprolactone (PCL) and biphasic calcium phosphates (BCP) that wound around a hollow electrospun PCL nanofibrous tube (the core). The porous helical shell supported the formation of bone-like tissues, while the luminal surface of nanofibrous core enabled endothelialization to mimic the function of Haversian canal. Culture of mouse pre-osteoblasts (POBs, MC 3T3-E1) onto the coil shells revealed that coils with pitch sizes greater than 135 μm, in the presence of BCP, favored the proliferation and osteogenic differentiation of POBs. The luminal surface of PCL nanofibrous core supported the adhesion and spreading of mouse endothelial cells (ECs, MS-1) to form a continuous endothelial lining with the function similar to blood vessels. Taken together, the shell–core bi-layered scaffolds with porous, coil-like shell and nanofibrous tubular cores represent a new scaffolding technology base for the creation of osteon analogs. 相似文献
83.
Sammer Marla B. K. Stahl Andrew Ozkan Eray Sher Andrew C. 《Journal of digital imaging》2021,34(3):741-749
Journal of Digital Imaging - In our pediatric radiology department, radiographs (XR) are the shared responsibility of the body section and interpreted in addition to modality or site-specific... 相似文献
84.
Ozkan T Tuncer S Aydin A Hosbay Z Gulgonen A 《The Journal of hand surgery, European volume》2004,29(3):265-270
A brachioradialis muscle rerouting procedure was used to restore active supination in five children with cerebral palsy and a pronation deformity. Following release and lengthening of the pronator quadratus and pronator teres muscles, respectively, the brachioradialis tendon was divided as a Z plasty and the distal part of the tendon was passed through the interosseous space in a dorsal to palmar direction, and then sutured to its proximal end. The procedure resulted in a gain of 81 degrees of active supination. 相似文献
85.
Parapneumonic effusions continue to be a significant source of morbidity and mortality. Treatment at earlier stages before fibrous peel and loculations occur has a much better prognosis. Using image guidance, addition of intracavitary fibrinolytic instillation, close follow-up with drainage of residual or new collections are some of the other factors that improve prognosis. In this article, we discussed treatment strategies, percutaneous management of parapneumonic effusions, its alternatives and results. 相似文献
86.
Tracheobronchial foreign bodies in children: importance of accurate history and plain chest radiography in delayed presentation 总被引:10,自引:0,他引:10
AIM: To evaluate the factors associated with delayed diagnosis of foreign body aspiration (FBA) in children and to compare clinical, radiological and bronchoscopic findings in the patients with suspected FBA. MATERIAL AND METHODS: The medical records of 214 children who underwent bronchoscopy for suspected FBA were reviewed. The data were analysed in three groups: the patients with negative bronchoscopy for FBA (group I), early (group II) and delayed diagnosis (group III). RESULTS: The majority of the patients with FBA were between 1 and 3 years of age. Choking episodes, coughing and decreased breath sounds were determined in a significantly higher number of the patients with FBA. The plain chest radiography revealed radio-opaque foreign bodies (FBs) in 19.7% of all patients with FBA. Emphysema was more common in children with FBA. Clinical and radiological findings of pneumonia and atelectasis were significantly more common in the groups with negative bronchoscopy and with delayed diagnosis (p < 0.01). The FBs were most frequently of vegetable origin, such as seeds and peanuts. A significant tissue reaction with inflammation was more common in the delayed cases. CONCLUSION: To prevent delayed diagnosis, characteristic symptoms, signs and radiological findings of FBA should be checked in all suspected cases. As clinical and radiological findings of FBA in delayed cases may mimic other disorders, the clinician must be aware of the likelihood of FBA. Regardless of radiological findings, bronchoscopy should be considered in patients with an appropriate history. 相似文献
87.
Sibel Ozkan Gurdal Ayse Nilufer Ozaydin Erkin Aribal Beyza Ozcinar Neslihan Cabiolu Cennet Sahin Vahit Ozmen 《Diagnostic and interventional radiology (Ankara, Turkey)》2021,27(2):157
PURPOSEWe aimed to show the effects of long-term screening on clinical, pathologic, and survival outcomes in patients with screen-detected breast cancer and compare these findings with breast cancer patients registered in the National Breast Cancer Registry Data (NBCRD).METHODSWomen aged 40–69 years, living in Bahcesehir county, Istanbul, Turkey, were screened every 2 years using bilateral mammography. The Bahcesehir National Breast Cancer Registry Data (BMSP) data were collected during a 10-year screening period (five rounds of screening). BMSP data were compared with the NBCRD regarding age, cancer stage, types of surgery, tumor size, lymph node status, molecular subtypes, and survival rates.RESULTSDuring the 10-year screening period, 8758 women were screened with 22621 mammograms. Breast cancer was detected in 130 patients; 51 (39.2%) were aged 40–49 years. The comparison of breast cancer patients in the two programs revealed that BMSP patients had earlier stages, higher breast-conserving surgery rates, smaller tumor size, more frequent negative axillary nodal status, lower histologic grade, and higher ductal carcinoma in situ rates than NBCRD patients (p = 0.001, for all).CONCLUSIONThese results indicate the feasibility of successful population-based screening in middle-income countries.Breast cancer is the most frequent cancer and cause of cancer-related deaths among Turkish women, as well as globally (1–5). Although the incidence of breast cancer increases every year, mortality rates are decreasing in developed countries because of nationwide screening programs and modern treatment options (5, 6). An invited mammography screening program for women aged between 40 and 69 years revealed a 60% reduction in cancer-related 10-year mortality in a landmark study (7). A systematic review of Myers et al. (8) showed that breast cancer screening reduced mortality by 20% in average-risk women of all age groups. However, this review did not evaluate the differences between annual and biannual mammographic screening.In 2004, the Cancer Control Department of Turkey recommended biannual mammographic screening for women aged 50–69 years, based on European Guidelines. The population of Turkey is relatively young, and almost half of all breast cancer patients in Turkey are younger than 50 years. According to and National Breast Cancer Registry Data (NBCRD) reports, the starting age for mammography screening was set as 40 years. The Bahcesehir Mammographic Screening Program (BMSP) was the first organized population-based 10-year (2009–2019) mammography screening program in Turkey, a middle-income country.Turkish Federation of Breast Diseases Societies started a voluntary data registry program that was provided by breast surgeons working in secondary or tertiary hospitals. This program aimed to collect detailed information of breast cancer patients and to pool comprehensive country-specific breast cancer data. This registry, namely the NBCRD, was the first specified database on breast cancer in the country and was started in 2005, before the BMSP (9). Data from 36 centers were collected for 10 years. However, the cancer registry is a standard database containing general information as defined by the International Agency for Research on Cancer standards.The aim of this study was to show the feasibility of a population-based breast cancer screening program in an emerging, middle-income country, Turkey. The objective of our study was to evaluate the effectiveness of a population-based breast cancer screening program by comparing it with NBCRD data. 相似文献
88.
Evaluation of flow hemodynamics by color-Doppler following two different brachial arterial repair techniques. 总被引:1,自引:0,他引:1
S Kili? A K Bacako?lu A Y G?ktay M H Ozkan G Erg?r K Bayatli A Gürbüz A Ekin 《European journal of vascular and endovascular surgery》2004,28(3):310-316
OBJECTIVES: We compared the clinical and hemodynamic results following surgical repair of traumatic brachial artery injury using two different techniques micro- and macrovascular repair. MATERIALS AND METHODS: This was a retrospective study of 27 patients who had sustained penetrating, clean cut injuries of the brachial artery. Macrovascular techniques and a saphenous vein graft was used in 13 patients, while 14 patients were treated by primary microsurgical technique. Postoperatively, patients were followed for a mean of 26 months. All patients had color Doppler examination of the brachial artery, digital artery pressures and transcutaneous oxygen saturation determined. RESULTS: Clinical results based on distal pulses, Allens test and digital pressures were similar in the two groups. Color Doppler showed 8/13 anastomotic stenoses in macrovascular vein grafted repairs and 2/14 in microvascular repairs (p<0.05). The ratio of flow velocity proximal compared distal to the injury was significantly decreased in patients who had macrovascular repairs. CONCLUSION: Using ratio between proximal and distal site of anastomosis maximal peak systolic velocity as a objective color Doppler parameter, we were able to demonstrate differences in the hemodynamic status following macrovascular repair with vein grafts and microvascular primary repair. The results emphasize the importance of using a standard repair technique for similar injuries rather than the preference of the surgeon. 相似文献
89.
Purpose
The aim of this study was to compare the efficacy of serum amyloid A (SAA) with that of C-reactive protein (CRP), and procalcitonin (PCT) in diagnosis and follow-up of necrotizing enterocolitis (NEC) in preterm infants.Methods
A total of 152 infants were enrolled into this observational study. The infants were classified into 3 groups: group 1 (58 infants with NEC and sepsis), group 2 (54 infants with only sepsis), and group 3 (40 infants with neither sepsis nor NEC, or control group). The data including whole blood count, CRP, PCT, SAA, and cultures that were obtained at diagnosis (0 hour), at 24 and 48 hours, and at 7 and 10 days were evaluated.Results
A total of 58 infants had a diagnosis of NEC. Mean CRP (7.4 ± 5.2 mg/dL) and SAA (46.2 ± 41.3 mg/dL) values of infants in group 1 at 0 hour were significantly higher than those in groups 2 and 3. Although the area under the curve of CRP was higher at 0 hour in infants with NEC, there were no significant differences between groups with respect to the areas under the curve of SAA, CRP, and PCT at all measurement times. Levels of SAA decreased earlier than CRP and PCT in the follow-up of NEC (mean SAA levels were 45.8 ± 45.2, 21.9 ± 16.6, 10.1 ± 8.3, and 7.9 ± 5.1 mg/dL at evaluation times, respectively). Levels of CRP and SAA of infants with NEC stages II and III were significantly higher than those with only sepsis and/or NEC stage I.Conclusions
Serum amyloid A, CRP, and PCT all are accurate and reliable markers in diagnosis of NEC, in addition to clinical and radiographic findings. Higher CRP and SAA levels might indicate advanced stage of NEC. Serial measurements of SAA, CRP, and PCT, either alone or in combination, can be used safely in the diagnosis and follow-up of NEC. 相似文献90.