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排序方式: 共有1425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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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6.
Alper Alkan Erdal Erdem Omer Günhan Cimen Karasu 《Journal of oral and maxillofacial surgery》2002,60(8):898-904
PURPOSE: Bone healing is impaired in diabetes mellitus, particularly due to increased collagen breakdown. Recently, tetracyclines have been used to treat experimental bone defects because they have anticollagenolytic properties, and positive effects on the healing process have been obtained. The objective of this study was to develop a computer-assisted histomorphometric technique to quantitatively determine the amount of regenerating bone within experimental bone defects in a diabetic rodent model. MATERIALS AND METHODS: This study examined the effects of systemic doxycycline administration on the healing of tibial bone defects in healthy albino rats and in experimentally induced diabetic rats. Twenty-four female albino rats were assigned to 4 groups: diabetic, diabetic plus doxycycline, control, or control plus doxycycline. The standardized bone defects were histomorphometrically examined 10 and 30 days postoperatively. Histomorphometric analysis of the amount of new bone formation was performed using the Zeiss Vision image analysis program KS 400 (Kontron Elektron GmbH, Eching, Germany). RESULTS: At 10 days of healing, the diabetic groups exhibited inferior healing compared with the control groups in terms of the amount of new bone formation within the defects. However, the effect of doxycycline administration to the diabetic and control groups was not statistically different. At 30 days of healing, there were no statistically significant differences between the amount of newly formed bone in any of the groups. CONCLUSIONS: This study found that doxycycline administration did not significantly alter the amount of new bone formation during the healing of bone defects in control and diabetic rats. 相似文献
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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
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Altintaş DU Karakoç GB Yilmaz M Pinar M Kendirli SG Cakan H 《Clinical & developmental immunology》2004,11(1):87-96
BACKGROUND: Aeroallergen sampling provides information regarding the onset, duration and severity of the pollen season that clinicians use to guide allergen selection for skin testing and treatment. OBJECTIVES: This atmospheric survey reports (1) airborne pollen contributions in Adana in one-year period (2) pollen onset, duration and peak level (3) the relationship between airborne pollen and selected meteorological variables and; (4) effects on symptoms in pollen allergic children. METHODS: Pollen sampling was performed with a volumetric Burkard Spore Trap. Meteorological data were measured daily from April 2001 to April 2002. Asthma symptom scores were investigated in 186 pollen allergic children that were on follow up in pediatric allergy outpatient clinics during same period. RESULTS: Average measurements included 82.5% tree pollen, 7.7% grass pollen and 9.8% herb pollen 54 taxa were identified during one year. The most prominent tree pollens were Cupressaceae, Eucalyptus and Pinus. The most common herb was Chenopodiaceae pollen family. When airborne pollen levels were examined in relation to single meteorological conditions; daily variations in total pollen counts were not significantly correlated with any variable studied (humidity, rainfall, temperature and wind) (p > 0.05). On the other hand, statistically significant relationship between pollen concentration and symptom scores were found (p > 0.05). Positive correlations were seen between both Gramineae and Herb pollen, and humidity and rainfall from March to July. However, positive correlations were detected between tree pollen counts and temperature and humidity in May and June. CONCLUSION: This survey is the first volumetric airborne pollen analysis conducted in the survey area in Adana. This study suggested that the effects of weather on pollen count and symptom scores in this population could not be clearly identified with the evaluation of one-year data. However, pollen counts had effect on allergic symptoms in pollen allergic children. Examination of the complex interaction of multiple whether parameters would perhaps more fully elucidate the relationship between meteorology and aerobiology and provide the clinician with information necessary to forecast pollen prevalence. An awareness of the ever chancing, local aeroallergen patterns requires regular monitoring. Such awareness serves as a useful guide in the effective testing and treatment of atopic patients. 相似文献
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A mixture of experts network structure for modelling Doppler ultrasound blood flow signals 总被引:1,自引:0,他引:1
Mixture of experts (ME) is a modular neural network architecture for supervised learning. This paper illustrates the use of ME network structure to guide modelling Doppler ultrasound blood flow signals. Expectation-Maximization (EM) algorithm was used for training the ME so that the learning process is decoupled in a manner that fits well with the modular structure. The ophthalmic and internal carotid arterial Doppler signals were decomposed into time-frequency representations using discrete wavelet transform and statistical features were calculated to depict their distribution. The ME network structures were implemented for diagnosis of ophthalmic and internal carotid arterial disorders using the statistical features as inputs. To improve diagnostic accuracy, the outputs of expert networks were combined by a gating network simultaneously trained in order to stochastically select the expert that is performing the best at solving the problem. The ME network structure achieved accuracy rates which were higher than that of the stand-alone neural network models. 相似文献
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Doppler ultrasound is known as a reliable technique, which demonstrates the flow characteristics and resistance of ophthalmic arteries. In this study, ophthalmic arterial Doppler signals were obtained from 106 subjects, 54 of whom suffered from ocular Behcet disease while the rest were healthy subjects. Multilayer perceptron neural network (MLPNN) employing delta-bar-delta training algorithm was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by least squares (LS) autoregressive (AR) method for determining the MLPNN inputs. The MLPNN was trained with training set, cross validated with cross validation set and tested with testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the MLPNN. The correct classification rate was 96.43% for healthy subjects and 93.75% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the MLPNN employing delta-bar-delta training algorithm was effective to detect the ophthalmic arterial Doppler signals with Behcet disease. 相似文献