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81.
Bulent Demir Ilker Murat Caglar Ismail Ungan Murat Ugurlucan Hande Oktay Tureli Osman Karakaya 《Archives of Medical Science》2013,9(6):1055-1061
Introduction
Platelets play a major role in thromboembolic events. Increased mean platelet volume (MPV) indicates higher platelet reactivity and also a tendency to thrombosis. Patent foramen ovale (PFO), persistence of the fetal anatomic shunt between right and left atria, is strongly associated with cryptogenic stroke. The aim of this study is to determine the relationship between MPV and PFO and if such an association exists, whether higher MPV levels may require antiplatelet therapy before a thromboembolic event happens, together with a literature review.Material and methods
Thirty patients (15 women, 15 men), free of any cerebrovascular events, were diagnosed with PFO by transesophageal echocardiography (TEE), enrolled as the study group. Thirty consecutive patients (16 women and 14 men), who were diagnosed as normal in TEE, were enrolled as the control group. These two groups were compared according to MPV and anatomical features of the right atrium.Results
There was no significant difference between study and control groups in clinical features and also no difference was observed in platelet counts; however, MPV in the PFO group was significantly higher than the control group (8.38 ±0.93 fl and 7.45 ±0.68 fl respectively).Conclusions
Our results indicate that elevated MPV may be detected in patients with PFO. This might be one of the explanations for the relationship between PFO and cryptogenic stroke; however, larger cohorts are warranted in order to define further mechanisms. 相似文献82.
An investigation was carried out on equal-channel angular pressing (ECAP) and extrusion processing of a ZM21 Mg alloy to obtain an improved candidate material for the manufacturing of biodegradable Mg stents. Ultrafine-grain size billets of the ZM21 alloy were obtained by two-stage ECAP aimed at achieving an initial refining of the structure at 200 °C and then reaching the submicrometer grain size range by lowering the processing temperature down to 150 °C. The investigation revealed a significant improvement in the properties of the ECAP-treated samples compared with the starting coarse-grained ZM21 alloy. The 0.2% yield strength rose from 180 to 340 MPa after 150 °C ECAP processing, while maintaining a fairly high tensile ductility. The ultrafine ZM21 alloy billets were then used for the extrusion of stent precursors having the form of small-size tubes. The grain size after extrusion remained in the submicrometer range while the hardness was revealed to be significantly higher than that of the coarse-grained ZM21 Mg alloy. It was demonstrated that processing of biodegradable Mg stent having an ultrafine-grained microstructure by ECAP and low-temperature extrusion is feasible and that the obtained products feature promising properties. 相似文献
83.
84.
Aytekin E Caglar NS Ozgonenel L Tutun S Demiryontar DY Demir SE 《Clinical rheumatology》2012,31(1):91-97
The home-based exercise therapy recommended to the patients with ankylosing spondylitis (AS) is a simply applicable and cheap
method. The aim of this study was to investigate the effects of home-based exercise therapy on pain, mobility, function, disease
activity, quality of life, and respiratory functions in patients with AS. Eighty patients diagnosed with AS according to the
modified New York criteria were included in the study. Home-based exercise program including range of motion, stretching,
strengthening, posture, and respiratory exercises was practically demonstrated by a physiotherapist. A training and exercise
manual booklet was given to all patients. Patients following home-based exercise program five times a week at least 30 min
per session (exercise group) for 3 months were compared with those exercising less than five times a week (control group).
Visual analog scale pain (VASp) values at baseline were significantly higher in the exercise group. The exercise group showed
improvements in VASp, tragus–wall distance, morning stiffness, finger–floor distance, modified Schober's test, chest expansion,
the Bath Ankylosing Spondylitis Disease Activity Index, the Bath Ankylosing Spondylitis Functional Index, Ankylosing Spondylitis
Quality of Life Questionnaire (ASQoL), forced expiratory volume in first second, and forced vital capacity at third month.
There was significant difference in ASQoL scores between the two groups in favor of the exercise group at third month. Regular
home-based exercise therapy should be a part of main therapy in patients with AS. Physicians should recommend that patients
with AS do exercise at least five times a week at least 30 min per session. 相似文献
85.
Orüm H Pamuk GE Pamuk ON Demir M Turgut B 《Journal of thrombosis and thrombolysis》2012,33(2):154-159
Recently, it has been reported that ankylosing spondylitis (AS) was characterised by endothelial dysfunction and the development
of atherosclerotic complications. In this study, we evaluated platelet and endothelial activation parameters in AS patients.
Fiftynine AS patients and 22 healthy controls were included. The clinical features and acute phase parameters were evaluated.
In all patients and healthy controls, platelet-monocyte complexes (PMC), platelet-neutrophil complexes, basal and ADP-stimulated
P-selectin (CD62P) expression were determined by flow cytometry; soluble E-selectin (sE-selectin) and soluble CD40L (sCD40L)
were determined by ELISA. AS patients were divided into two groups as active and inactive by using BASDAI. In 15 AS patients,
the evaluated parameters were assessed before and after 12 weeks of anti-TNF therapy. PMC and sCD40L levels in AS patients
were significantly higher than in the control group (P values 0.013 and 0.016). The evaluated variables were similar in active and inactive AS groups (P > 0.05). There were no significant changes in platelet and endothelial activation parameters in AS patients after anti-TNF
therapy (P > 0.05). Platelet activation which is reflected by high levels of PMC and sCD40L might be responsible for the increased frequency
of atherosclerosis in AS. The platelet activation in our AS patients was not associated with disease activity and did not
improve after anti-TNF therapy. 相似文献
86.
87.
The aim was to evaluate the concentrations of lipid subfractions in relation to adipokines and metabolic parameters in adult growth hormone (GH)-deficient hypopituitary patients on conventional replacement therapy. The study included 21 GH deficient-hypopituitary patients (age: 36.0 ± 15.1 years, male/female: 7/14) on conventional replacement therapy other than GH and 20 comparable controls (age: 37.3 ± 14.0 years, male/female: 6/14). Lipid subfractions (Lipoprint system), serum adipokine (leptin, adiponectin, resistin) concentrations, body composition, a surrogate marker for insulin resistance (HOMA) and conventional lipid profile were evaluated. No statistically significant difference was found with respect to HOMA, adipokine concentrations and anthropometric parameters between patients and controls except for significantly increased waist-to-hip ratio in hypopituitary group. Total and LDL cholesterol concentrations were significantly higher in the patients. LDL particle size (268.88 ± 3.16 vs. 271.31 ± 3.11 ?, P = 0.151) and small-dense LDL subfraction did not differ significantly. According to logistic regression analysis, triglyceride concentrations ≥1.69 mmol/L was the sole parameter significantly and independently predicted small (<268 ?) LDL particle size (P = 0.019) in the whole group. Increased triglyceride concentrations affect LDL particle size in GH-deficient hypopituitary patients. Small dense LDL seems not directly contribute to atherogenic potential in hypopituitarism. 相似文献
88.
Gurcan Dogukan Arslan Dilek Guven Mehmet Demir Abdurrahman Alpaslan Alkan Delil Ozcan 《Indian journal of ophthalmology》2021,69(5):1189
Purpose:The aim of this study was to evaluate the structural and functional changes occurring in patients with branch retinal vein occlusion (BRVO) according to the distance of the affected arteriovenous (AV) crossing to the centers of the fovea and optic disc by optic coherence tomography angiography (OCTA).Methods:Forty-five patients with unilateral BRVO and 45 age- and sex-matched healthy controls were included in this retrospective observational study. Images of the macula (3 mm × 3 mm) and affected AV crossing sites were obtained by OCTA. The fovea-AV crossing distance (FAVD), optic disc-AV crossing distance (DAVD), and optic disc-fovea distance (DFD) were measured.Results:The FAVD/DFD ratio was positively correlated with the vessel density in the superficial and deep affected hemifields (r = 0.430, P < 0.05 and r = 0.308, P < 0.05, respectively) and negatively correlated with the superficial foveal avascular zone and logarithm of the minimum angle of resolution (logMAR) visual acuity (r = –0.412, P < 0.05 and r = –0.356, P < 0.05, respectively). The DAVD/DFD ratio was not correlated with the logMAR visual acuity, superficial FAZ area or vessel densities in the affected hemifield (all P > 0.05).Conclusion:The affected AV crossing site that was further away from the fovea had better visual acuity and quantitative microvascular parameters in the affected hemifields. However, this correlation was not observed for the distance between the affected AV crossing site and the optic disc. 相似文献
89.
90.
Nüvit Duraker Bakir Batı Zeynep Civelek Çaynak Davut Demir 《World journal of surgery》2013,37(6):1241-1248