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排序方式: 共有3010条查询结果,搜索用时 15 毫秒
1.
Senem Maral Muradiye Acar Ozlem Sahin Balcik Eyyup Uctepe Omer Faruk Hatipoglu Derya Akdeniz Hatice Uludag Altun Ali Kosar Mehmet Gunduz Esra Gunduz 《Medicine》2015,94(16)
Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment. 相似文献
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Ozlem Coskun Serap Ucler Leyla Cavdar Levent E Inan 《Journal of clinical neuroscience》2007,14(4):334-339
Discontinuation of medication is the treatment of choice for patients with chronic daily headache (CDH) who overuse their medications. This treatment may be difficult due to increased headache severity observed in patients immediately after withdrawal. We retrospectively evaluated the efficacy of valproic acid therapy in 66 patients with overuse of CDH medication during withdrawal therapy. Patients were all withdrawn from medications and valproic acid started at 250 mg or 500 mg daily. Forty-two (63.6%) patients had decreased headache severity, including 27.3% objective responses in the first week. At the last visit in the 12th week, 50 patients were headache-free and only one patient had persistent headache. Fifteen patients withdrew from therapy due to side effects and lost to follow-up within this timeframe. Thus, low dose valproic acid appears to be safe and effective in the management of withdrawal therapy. 相似文献
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Cankurtaran Ozlem Olgac Guven Kutlu Cemal Asim 《Indian Journal of Thoracic and Cardiovascular Surgery》2004,20(2):91-92
Indian Journal of Thoracic and Cardiovascular Surgery - 相似文献
6.
Julide Ozen Bahar Dirican Kaan Oysul Murat Beyzadeoglu Ozlem Ucok Bedri Beydemir 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,99(6):743-747
OBJECTIVE: The aim of the study was to examine the dose enhancement from scattered radiation at bone-dental implant interfaces during simulated head and neck radiotherapy. STUDY DESIGN: Four cylindrical titanium dental implants with 3 different sizes and lengths were implanted into a human mandible in 4 different positions. Ionization measurements for 6 MV X, 25 MV X, and Co-60 gamma rays were done. Thermoluminescent dosimeter (TLD 100 ) chips were used to measure radiation dose enhancement due to the scattered electrons from titanium and electronic disequilibrium at the tissue-metal interface. RESULTS: The results showed that for Co-60, there is a 21% maximum increase in dose to alveolar mandibular bone at the close proximity to the titanium. For 6-MV x-rays the dose enhancement increase was almost the same or slightly lower than for Co-60, while for 25-MV high-energy x-rays, dose enhancement was lower than that of others. This increase in dose enhancement fell off rapidly and became insignificant at 2 mm from the interface. CONCLUSION: Total dose that may lead to osteoradionecrosis risk of the mandible is slightly but not significantly affected by the scattered dose of the dental implants of lower jaw in the radiation field exposed to 3 different radiation beams. 相似文献
7.
M. Ïmer T. Okar S. Çobanoğlu R. Kayapinar M. Memiş K. Hepgül K. Kutlu 《Acta neurochirurgica》1996,138(10):1246-1249
Summary Modification of a type of end-to-side anastomosis that has been described before is studied. The recipient artery is occluded for only 3–4 minutes to complete the anastomosis by using only the running suture. The anastomotic site was studied by inspection and Scanning Electron Microscope (SEM) at different times after the operation on 30 rats. 相似文献
8.
Yazicioglu M Oner N Celtik C Okutan O Pala O 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》2004,22(4):183-190
Asthma and allergic rhinitis are common problems in children and the causative pollen allergens vary according to the geographical area. The aim of this study was to investigate patterns of sensitization to common inhalant allergens, especially pollens, in Turkish children living in the Trakya region and to determine differences between rural and urban areas. Allergen skin testing was prospectively performed on 539 children aged between 4 and 17 years with respiratory allergy. The reaction was considered to be positive if the mean wheal diameter was at least 3 mm greater than that of the negative controls. We detected positive skin reactions in 420 (77.9%) children. Two hundred and eighty-one (52.1%) mite, 277 (51.4%) pollen, 174 (32.3%) mold, 65 (12.1%) animal dander, 12 (2.2%) cockroach and 6 (1.1%) latex skin sensitivities were detected. Among the pollen allergies 173 were cereal pollen (32.1%), 170 grass pollen (31.5%) and 144 tree pollen allergies (26.7%). The most common positive skin test among the pollens was to cultivated wheat (Titicum vulgare) (n = 116, 21,5%), followed by rye grass (Lolium perenne) and orchard grass (Dactylis glomerata). Positive skin reactions to Alternaria, to Candida albicans, and to all pollens except Ulmus competris, Pinus sylvetris, Platanus vulgaris and Tilia platyphyllos, were higher in children with allergic rhinitis than in those with asthma. In children from rural areas, allergic skin reactivity was found to be more common against Candida albicans, sheep dander and all pollens except Corylus avellana, Fraxinus excelsior, Populus alba, Pinus sylvetris, Platanus vulgaris and Chenopodium album, than in urban children. Although Trakya is close to Greece and other Mediterranean countries, this study suggests that the pollens, which sensitize children, are not similar. 相似文献
9.
Cevik MO 《Behavioral neuroscience》2003,117(4):774-784
Experiments 1 and 2 address the controversy regarding the reliability of methamphetamine effects on interval timing. A temporal discrimination procedure was used, in which the rats were reinforced for pressing the left or the right levers after short and long signals, respectively. Methamphetamine (0.5 mg/kg sc) severely disrupted operant performance at 20-100 min after injection, which disabled the measurement of drug effects on temporal perception (Experiment 1). The same dose of methamphetamine shifted the psychometric function to the left at 100-180 min after injection, indicating an increase in subjective durations (Experiment 2). Although these results confirm the role of dopamine in interval timing, that a change in the speed of a neural clock mediates the methamphetamine-induced change in temporal perception is still a working hypothesis. 相似文献
10.
Morphology of the lumbar spinal canal in normal adult Turks 总被引:2,自引:0,他引:2
Pathological changes can occur in the diameters of the lumbar spinal canal. Therefore, assessing the canal size an important diagnostic procedure. Two hundred plain anterioposterior radiographs of the lumbar spine were examined. The sample consisted of 100 males and 100 females. The transverse diameter of the bony spinal canal (interpedicular distance), which was measured as the minimum distance between the medial surfaces of the pedicles of a given vertebra, was measured. In addition, the transverse diameter of the vertebral body, which was measured as the minimum distance across the waist of the vertebra, was measured. The distances were measured to the nearest one tenth of a millimetere using a Vernier caliper. At all levels (L1 - L5) the transverse diameters of the lumbar spinal canal were approximately 1 - 1.5 mm higher in males than in females. The intersegmental differences increased proximodistally, in both sexes. The ratio of the transverse diameter canal to the width of the vertebra ranged from 0.55 to 0.60 mm in both sexes. The distribution of the different lumbar canal types were 47% A, 42% B, 11% C. Additionally, subtypes were determined and classified. 相似文献