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排序方式: 共有3619条查询结果,搜索用时 31 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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Burcin Ustbas Gul Deniz Kilic Yanilmaz Dilan Arslan Mehmet Bayramicli Ozge Akbulut 《Journal of plastic, reconstructive & aesthetic surgery》2019,72(3):477-483
Background
There is a need for a peripheral nerve model on which surgeons-in-training can simulate the repair of nerve injuries at their own pace. Although practicing on animal models/cadavers is considered the “gold standard” of microsurgical training, the proposed model aims to provide a platform for improving the technical skills of surgical trainees prior to their practice on cadaver/animal models. In addition, this model has the potential to serve as a standardized test medium for assessing the skill sets of surgeons.Methods
Several formulations of silicone were utilized for the design and fabrication of a model which realizes the hierarchical structure of peripheral nerves. The mechanical properties were characterized via the Universal Testing Machine; the damage caused by the needle on the entry sites was assessed through scanning electron microscopy (SEM).Results
Mechanical properties of the formulations of silicone were tested to mimic human peripheral nerves. A formulation with 83.3?wt% silicone oil and 0.1?wt% cotton fiber was chosen to be used as nerve fascicles. Both 83.3?wt% silicone oil with cotton fiber and 66.6?wt% silicone oil without fiber provided a microsuturing response similar to that of epineurium at a wall thickness of 1?mm. SEM also confirmed that the entry of the needle did not introduce significant holes at the microsuturing sites.Conclusions
The proposed peripheral nerve model mimicked human tissues mechanically and cosmetically, and a simulation of the repair of a fifth-degree nerve injury was achieved. 相似文献5.
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Alan A Arslan Anne Zeleniuch-Jacquotte Annekatrin Lukanova Yelena Afanasyeva Joseph Katz Mortimer Levitz Giuseppe Del Priore Paolo Toniolo 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2123-2130
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk. 相似文献
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Background
The combination therapies recommended by the World Health Organization for treatment of brucellosis are doxycycline plus rifampicin or doxycycline plus streptomycin. Although highly successful results have been obtained with these two regimens, relapse rates as high as 14.4%. The most effective and the least toxic chemotherapy for human brucellosis is still undetermined. The aim of the present study was to investigate the efficacy, adverse effects and cost of ofloxacin plus rifampicin therapy, and doxycycline plus rifampicin therapy and evaluate in the treatment of brucellosis. 相似文献8.
Sabri Acarturk Emrah Arslan Ferit Demirkan Sakir Unal 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(4):409-16; discussion 417-8
Severe middle vault deformity with disturbed nasal form and function is one of the most challenging procedures to correct in a secondary rhinoplasty. Reconstructing the deformity with autologous septal cartilage would be the primary choice of most surgeons, if it were always available. However in certain cases the lack of a sufficient quantity of autologous cartilage has forced surgeons to explore other viable options. This paper discusses our experience with the combined use of spreader and dorsal onlay grafts from various materials in the reconstruction of severe middle vault deformity in 110 patients. In follow up, (between 6 and 42 months; mean 21 months) all patients were noted to have improved in both aesthetics and function with no major complications noted. In summary, this study proposes that any engrafting material can be used safely when the proper surgical principals and technique are employed. 相似文献
9.
Comparison of CT-guided sclerotherapy with using 95% ethanol and 20% hypertonic saline for managing simple renal cyst. 总被引:1,自引:0,他引:1
Hulusi Egilmez Vedat Gok Ibrahim Oztoprak Mehmet Atalar Ali Cetin Mubeccel Arslan Yener Gultekin Orhan Solak 《Korean journal of radiology》2007,8(6):512-519
OBJECTIVE: We wanted to compare the efficacies of 95% ethanol and 20% hypertonic saline (HS) sclerotherapies that were performed in a single session under CT guidance for the management of simple renal cysts. MATERIALS AND METHODS: A prospective series of 74 consecutive patients (average age: 57.6 +/- 8.1 years) with simple renal cysts were enrolled in this study. They were randomized into two groups and 95% ethanol or 20% HS, respectively, corresponding to 25% of the aspiration volume, was injected. Treatment success was determined six months later with follow-up clinical evaluation and performing ultrasonography. RESULTS: The sclerotherapy was accepted as technically successful without major complications in all except two patients who were excluded because of a communication between the simple renal cyst and the pelvicalyceal collecting system. Thirty-six patients in the ethanol group received sclerotherapy with 95% ethanol and 36 patients in the HS group underwent sclerotherapy with 20% HS. The complete regression ratio of the ethanol group was significantly higher (94% versus 72%, respectively) than that of the HS group. There was one patient with partial regression in each group. The failure ratio of the ethanol group was significantly lower (3% versus 25%, respectively) than that of the HS group. CONCLUSION: Ethanol sclerotherapy under CT guidance is a successful and safe procedure and it can be used for the treatment of simple renal cysts. Sclerotherapy with 95% ethanol is more effective than 20% HS sclerotherapy. Sclerotherapy with HS may be an option for patients preferring to undergo a less painful treatment procedure. 相似文献
10.
In this study, Doppler signals recorded from ophthalmic artery of 75 subjects were processed by PC-computer using classical and model-based methods. The classical method (fast Fourier transform) and three model-based methods (Burg autoregressive, moving average, least-squares modified Yule–Walker autoregressive moving average methods) were selected for processing ophthalmic arterial Doppler signals with uveitis disease. Doppler power spectra of ophthalmic arterial Doppler signals were obtained by using these spectrum analysis techniques. The variations in the shape of the Doppler spectra as a function of time were presented in the form of sonograms in order to obtain medical information. These Doppler spectra and sonograms were then used to compare the applied methods in terms of their frequency resolution and the effects in determination of uveitis disease. 相似文献