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11.
Thrombocytosis is an important laboratory finding in rheumatoid arthritis (RA) and it has a correlation with disease activity. Janus kinase 2 valin 617 phenylalanine (JAK2V617F) mutation has gained importance in the diagnosis of myeloproliferative diseases recently. There is no published report in literature on the association between RA and JAK2V617F-positive essential thrombocythemia (ET). In this report, we present a JAK2V617F-positive ET case that had RA. A 57-year-old male patient was diagnosed with RA according to the criteria of American College of Rheumatology (ACR), whose complaint was of pain in the hands and morning stiffness lasting for about 2 h. The patient was evaluated for thrombocytosis because he was in remission and suffering persistent thrombocytosis under treatment. After excluding the causes of secondary thrombocytosis, bone marrow aspiration and biopsy was performed. On peripheral blood and bone marrow PCR examination, the patient was detected to be JAK2V617F positive heterozygously and diagnosed with ET. As a conclusion, mild–moderate thrombocytosis is frequent in RA; however, ET can be diagnosed by JAK2V617F evaluation in peripheral blood in thrombocytosis, especially when platelet count is more than 1 million/ml and when persisting thrombocytosis is detected in RA remission.  相似文献   
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Background: Aortic stiffness is an independent risk factor for cardiovascular events and mortality. The measurement of pulse‐wave velocity (PWV) is the most simple, noninvasive, and robust method to determine aortic stiffness. Whether aortic stiffness contributes to aortic valve sclerosis (AVS) remains unknown. The aim of the present study was to examine the relationship between PWV and AVS in subjects free of clinically evident atherosclerotic disease. Methods: We enrolled 62 patients (48 men; age 65 ± 8 years) diagnosed with AVS and an additional 62 age‐, hypertension‐, diabetes mellitus‐, and history of smoking‐matched subjects without AVS. Applanation tonometry was applied to assess the augmentation index and aortic PWV. The subjects with symptomatic vascular disease were excluded from the study. AVS was defined by echocardiography as thickening and calcification of the normal trileaflet aortic valve without obstruction to the left ventricular outflow. Results: There was no significant difference between the two groups regarding the aortic PWV and augmentation index (11.7±3.3 vs 11.8±3.7, P=0.85; 28.0±9.4 vs 25.0±8.6, P=0. 17, respectively). The presence of AVS was significantly correlated with ejection fraction (r=0.211, P=0.011), male gender (r=0.362, P=0.0001), and age (r=0.200, P=0.026). Conclusions: The lack of an association between the aortic PWV and AVS suggests that AVS is a complex phenomenon consisting of several distinct processes, related to both atherosclerotic and nonatherosclerotic processes.  相似文献   
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The role of endothelial dysfunction and platelet activation in patients with cardiac syndrome X is controversial. The aim of this study was to investigate the plasma levels of circulating E- and P-selectin molecules in patients with syndrome X. The study included 21 patients with cardiac syndrome X (11 men and 10 women, mean age = 56 +/- 5 years) and 20 patients with significant coronary artery disease who had stable angina pectoris (11 men and 9 women, mean age = 60 +/- 8 years). Twenty-two age- and sex-matched subjects (12 men and 10 women, mean age = 58 +/- 8 years) undergoing diagnosis of atypical chest pain in whom coronary arteries were found normal and exercise test had no signs of ischemia served as the control group. Syndrome X was defined as presence of typical chest pain on exertion or at rest with positive exercise test and angiographically normal epicardial coronary arteries with no evidence of coronary spasm after intracoronary infusion of ergonovine maleate. The mean plasma concentrations of P-selectin were significantly elevated both in patients with coronary artery disease and syndrome X as compared with control subjects (49.15 +/-7.47 and 42.80 +/- 8.93 vs 22.63 +/-6.47 ng/mL, p < 0.001). Similarly, both patients with coronary artery disease and syndrome X had higher plasma concentrations of E-selectin than the control group (78.85 +/- 16.69 and 68.38 +/- 15.30 vs 36.43 +/- 4.72 ng/mL, p < 0.001). In conclusion, patients with syndrome X had increased plasma concentrations of soluble adhesion molecules, E-selectin and P-selectin, reflecting an ongoing chronic inflammation involved with endothelial dysfunction and enhanced platelet activation/damage in this setting.  相似文献   
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The wind energy sector is growing rapidly. Wind turbines are increasing in size, leading to higher tip velocities. The leading edges of the blades interact with rain droplets, causing erosion damage over time. In order to mitigate the erosion, coating materials are required to protect the blades. To predict the fatigue lifetime of coated substrates, the Springer model is often used. The current work summarizes the research performed using this model in the wind energy sector and studies the sensitivity of the model to its input parameters. It is shown that the Springer model highly depends on the Poisson ratio, the strength values of the coating and the empirically fitted a2 constant. The assumptions made in the Springer model are not physically representative, and we reasoned that more modern methods are required to accurately predict coating lifetimes. The proposed framework is split into three parts—(1) a contact pressure model, (2) a coating stress model and (3) a fatigue strength model—which overall is sufficient to capture the underlying physics during rain erosion of wind turbine blades. Possible improvements to each of the individual aspects of the framework are proposed.  相似文献   
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Hematological malignancies with renal cell carcinoma (RCC) are rarely seen. We reported here two cases of coincidence of RCC with multiple myeloma (MM) and Hodgkin??s disease (HD). A 69-year-old male patient with tumor that was located at the upper pole of left kidney was admitted to our clinic. Partial tumoral resection was perfomed and stage-I RCC was diagnosed after the histopathological examination of tumor. Moreover, he was diagnosed with IgG kappa stage-IIA MM as a result of bone marrow examination and serum immunofixation electrophoresis. Radiotherapy, combination chemotherapy, and autologous stem cell transplantation (ASCT) were performed. The patient is still alive who achieve a complete remission. A 53-year-old male patient suffered from cervival lymphadenopathy. He has a story of right radical nefrectomy that has been performed 4?years ago. Stage II-B lymphocyte-predominant HD was diagnosed. Combination chemotherapy was started, but relapse occurred 25?months later. ASCT was not planned due to cardiovascular problems and the patient died. Clinicans should keep in mind the coincidence of RCC with MM and HD.  相似文献   
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The aim is to evaluate the antioxidant enzyme levels in tumoral tissues and accompanying normal tissues in gastrointestinal cancer; and compare the colorectal cancer (CRC) with gastric cancer (GC).MethodAntioxidant enzymes including glutathione reductase (GR), glutathione peroxidase (GPX), superoxide dismutase (SOD), malondialdehyde (MDA) and glucose 6 phosphate dehyrogenase (G6PD) which are important for anti-oxidant functions were evaluated in fresh tumor tissues and adjacent normal tissues obtained from a total of 58 patients.ResultsAll the enzyme levels were higher in tumoral tissues compared to normal tissue from non-cancerous disease. There was not a significant difference for enzyme levels between CRC and GC groups except GPx. GPx activity tended to be higher in cases without serosal involvement (SI), and this activity was higher in cases without lymph node (LN) involvement in normal tissue (p = 0.012). MDA activity was higher in cases without serosal involvement compared to with SI groups in tumor tissue (p = 0.050). G6PD activity in normal tissue was higher in cases with serosal involvement and LN involvement (p = 0.064, 0.046, respectively). GR activity was higher in signet ring cell cancer (SRC) than adeno cancer. In GC, G6PD activity in tumor was tended to be higher in undifferentiated cancer (p = 0.071).ConclusionThe antioxidant enzymes activities such as GPX, SOD, G6PD, MDA and GR were found to be related with malignant phenotype in gastrointestinal cancers. We need further studies to understand the biologic and clinical importance of these enzymes in GI cancers.  相似文献   
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We prospectively evaluated 59 eyes following uneventful phacoemulsification and intraocular lens implantation with optic coherence tomography at one and seven postoperative days (POD). Acute vitreomacular traction was observed in two eyes (3.3%) at the first POD. Spontaneous resolution occurred in both eyes within one week. The temporary visual loss associated with acute vitreomacular traction syndrome may go unnoticed as visual acuity rapidly improves.  相似文献   
20.
Characteristics of intraocular bleeding and its management in association with blood dyscrasias are discussed. We present a patient with massive bilateral choroidal hemorrhage secondary to Glanzmann's syndrome. Magnetic resonance imaging and ultrasonographic findings were ordered. During the clinical course, bilateral intravitreal hemorrhage and tractional retinal detachment occurred. Left pars plana vitrectomy was performed under general anaesthesia. The procedure was unsuccessful because of intraoperative uncontrolled bleeding.  相似文献   
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