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791.
A case of solid pseudopapillary tumor of the pancreas 总被引:2,自引:0,他引:2
Karatag O Yenice G Ozkurt H Basak M Basaran C Yilmaz B 《World journal of gastroenterology : WJG》2006,12(38):6239-6243
INTRODUCTION Most pancreatic tumors are malignant and have a bad prognosis. However, solid-pseudopapillary tumor of the pancreas (SPT) is a rare benign or low-grade malignancy. Because of this, it is important to make the diagnosis of this tumor preoperat… 相似文献
792.
Renin–angiotensin system gene polymorphisms: association with susceptibility to Henoch–Schonlein purpura and renal involvement 总被引:4,自引:0,他引:4
Ozkaya O Söylemezoğlu O Gönen S Misirlioğlu M Tuncer S Kalman S Buyan N Hasanoğlu E 《Clinical rheumatology》2006,25(6):861-865
The clinical course of Henoch–Schönlein Purpura (HSP) in children is variable, with some patients having a much more rapidly progressing course than others. We investigated whether polymorphisms of the renin–angiotensin system (RAS) genes are involved in HSP. Three RAS genotypes were examined in 114 children with HSP and in 164 healthy children: the angiotensin I converting enzyme (ACE) insertion/deletion polymorphism, the M235T mutation in the angiotensinogen gene (Agt), and the A1166C in the angiotensin II type I receptor (AT1R) gene. Significant differences were observed between HSP patients and control group in the frequency of ACE and Agt genotypes (p=0.004 and p=0.003, respectively). The TT genotype of Agt gene was associated with a 3.5-fold increased risk for Henoch–Schönlein nephritis (HSN) compared with the MM/MT genotype (odds ratio, 3.5; 95% confidence interval, 1.2–10.4). There was a trend to a higher prevalence of the TT genotype of the Agt gene among patients with nephrotic range proteinuria when compared to the patients with mild proteinuria, although the difference did not reach a statistical significance. The results of this study suggest that polymorphisms of ACE gene and Agt gene likely influence the risk of developing HSP. However, among the three genes of the RAS studies, only Agt gene was associated with the susceptibility to HSN. RAS gene polymorphisms studied are not associated with the presence of nephrotic range proteinuria. Additional studies are warranted to verify the correlation between RAS gene polymorphisms and susceptibility to HSP. 相似文献
793.
Infection with Chlamydia pneumoniae but not Helicobacter pylori is related to elevated apolipoprotein B levels 总被引:2,自引:0,他引:2
OBJECTIVE: Results of many studies show that apolipoprotein B (apo B) is a better marker of risk of vascular disease than other lipid markers including LDL and HDL-cholesterol and triglycerides. We investigated the association between two infectious agents: C. pneumoniae and H. pylori, known to have an atherogenic effect, and apo B, to evaluate the effects of chronic infections on apo B levels. METHODS AND RESULTS: The study group consisted of 257 patients in whom diagnostic coronary angiography was performed. C. pneumoniae IgG and IgM and H. pylori IgG and IgA antibodies were measured by enzyme-linked immunosorbent assay and apo B levels were measured by the nephelometry method. Established risk factors of atherosclerosis were recorded. Of 257 patients recruited, 104 had normal vessels, 88 had 3 or more vessels obstructed and 65 had ectatic vessels without atherosclerosis. Mean apo B concentration was significantly higher in C. pneumoniae IgG and IgM positive healthy subjects compared with C. pneumoniae negatives (0.954 vs. 0.722 and 0.973 vs. 0.851, p < 0.001 and p = 0.007, respectively). Apo B levels were significantly higher in severe atherosclerotic patients (0.985 +/- 0.234 g/l) compared with control subjects (0.892 +/- 0.244 g/l) (p = 0.008), but the difference was not significant in ectatic subjects (0.946 +/- 0.272 g/l) when compared with controls (p = 0.18). Apo B levels were higher but not statistically significant in H. pylori antibody positive cases when compared with negatives. CONCLUSIONS: Apo B levels increased with C. pneumoniae infection. This finding supports the hypothesis that lipid profiles change to atherogenic lipid profile in chronic infections. 相似文献
794.
Tamer Cebe Karolin Yanar P?nar Atukeren Tuna Ozan Aylin Irmak Kuru? Ahmad Kunbaz Mustafa Erin? Sitar Murat Mengi Mehmet ?erif Ayd?n Mukaddes E?refo?lu Seval Ayd?n Ufuk ?akatay 《Age (Dordrecht, Netherlands)》2014,36(6):9728
Age-related myocardial dysfunction has important implications with impaired redox homeostasis. Current study focused on investigation of redox homeostasis and histopathological changes in the myocardium of mimetically (MA), naturally aged (NA), and young control (YC) rats. Chronic d-galactose administration to young male Wistar rats (5 months old) was used to set up experimental aging models. We investigated 16 different oxidative damage biomarkers which have evaluated redox homeostasis of cellular macromolecules such as protein, lipid, and DNA. As a protein oxidation biomarker, advanced oxidation end products, protein carbonyl groups, protein-bound advanced glycation end products, dityrosine, kynurenine, and N-formylkynurenine concentrations in MA and NA rats were found to be significantly higher compared to those in YC rats. On the other hand, the levels of protein thiol groups were not significantly different between groups, whereas lipid peroxidation biomarkers such as conjugated diens, lipid hydroperoxides, and malondialdehyde in MA and NA rats were found to be significantly higher in comparison to those in YCs. For the assessment of oxidative DNA damage, we analyzed eight hydroxy-5′-deoxyguanosine concentrations of MA and NA groups which were higher than YCs. As an antioxidant status in the MA and NA groups, Cu–Zn superoxide dismutase, ferric reducing antioxidant power, and total thiol levels were lower than those in the YCs. Only nonprotein thiol levels were not significantly different. We also observed similar histopathological changes in MA and NA rats. We concluded that the mimetic aging model could be considered as a reliable experimental model for myocardial senescence. 相似文献
795.
Ozan Mustafa Gürsoy M.D. Süleyman Karakoyun M.D. Macit Kalçık M.D. Mehmet Özkan M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(7):E198-E201
Purpose: Although nonobstructive prosthetic valve thrombosis (PVT) does not develop hemodynamic compromise, it carries potential risk for thromboembolism. Real time three‐dimensional transesophageal echocardiography (RT‐3DTEE), has emerged as a complementary tool in depicting “en face” views of prosthesis compared with two‐dimensional transesophageal echocardiography (2DTEE). We aimed to evaluate the utility of RT‐3DTEE in assessment of mitral ring‐located thrombosis. Method: We present 3 cases of mechanical mitral valve thrombosis complicated by thromboembolism, who were all examined and followed‐up by 2D transthoracic echocardiography (TTE), 2DTEE, and RT‐3DTEE. Result: The consequencies of thromboembolism in the patients were coronary embolism, transient ischemic attack, and ischemic stroke, respectively. They were all inadequately anticoagulated at the time of admission. 2DTTE and TEE examination was unsatisfactory; RT‐3DTEE depicted nonobstructive mitral ring thrombosis in each of the patients. The patients were followed up under effective anticoagulation and antiplatelet therapy. RT‐3DTEE was able to demonstrate the evolution of thrombus size in each of the patients. Conclusion: Nonobstructive ring‐located PVT which poses risk for thromboembolism, may be diagnosed with certainty and imaged with clarity utilizing RT‐3DTEE. 相似文献
796.
Ozge Gumusay Ugur Coskun Tülay Akman Ahmet Siyar Ekinci Muharrem Kocar Özlem Balvan Erceleb Ozan Yazıcı Mehmet Ali Kaplan Veli Berk Bulent Cetin Burcu Yapar Taskoylu Ayhan Yildiz Gamze Goksel Ahmet Alacacioglu Umut Demirci Efnan Algin Mukremin Uysal Ilhan Oztop Berna Oksuzoglu Faysal Dane Mahmut Gumus Suleyman Buyukberber 《Journal of cancer research and clinical oncology》2014,140(1):151-157
Background
The development of brain metastases (BMs) was associated with poor prognosis in melanoma patients. Patients with BMs have a median survival of <6 months. Melanoma is the third most common tumor to metastasize to the brain with a reported incidence of 10–40 %. Our aim was to identify factors predicting development of BMs and survival.Patients and methods
We performed a retrospective analysis of 470 melanoma patients between 2000 and 2012. The logistic regression analyses were used to identify the clinicopathological features of primary melanoma that are predictive of BMs development and survival after a diagnosis of brain metastases.Results
There were 52 patients (11.1 %) who developed melanoma BMs during the study period. The analysis of post-BMs with Kaplan–Meier curves has resulted in a median survival rate of 4.1 months (range 2.9–5.1 months). On logistic regression analysis site of the primary tumor on the head and neck (p = 0.002), primary tumor thickness (Breslow >4 mm) (p = 0.008), ulceration (p = 0.007), and pathologically N2 and N3 diseases (p = 0.001) were found to be significantly associated with the development of BMs. In univariate analysis, tumor thickness and performance status had a significant influence on post-BMs survival. In multivariate analysis, these clinicopathologic factors were not remained as significant predictive factors.Conclusions
Our results revealed the importance of primary tumor characteristics associated with the development of BMs. Ulceration, primary tumor thickness, anatomic site, and pathologic ≥N2 disease were found to be significant predictors of BMs development. 相似文献797.
The Current Status of Fluoroscopy and Echocardiography in the Diagnosis of Prosthetic Valve Thrombosis—A Review Article 下载免费PDF全文
Mustafa Ozan Gürsoy M.D. Macit Kalçik M.D. Süleyman Karakoyun M.D. Mehmet Özkan M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(1):156-164
Prosthetic valve thrombosis (PVT) is a potentially life‐threatening complication of heart valve replacement. Early diagnosis is crucial for the prevention of significantly morbid and lethal complications. Cinefluoroscopy (CF) and echocardiography have been widely used for diagnosing PVT. In recent years, the role of CF has declined since the introduction of transesophageal echocardiography and the great improvements in ultrasound technology including real time three‐dimensional imaging. Nevertheless, both echocardiography and CF provide different kinds of information on prosthesis function, and therefore they are considered as complementary and not alternative. In this review, we aimed to summarize the current status of CF and echocardiography in the diagnosis of PVT. 相似文献
798.
Bar SAYLAM Ozan EFESOY Rabia BOZDOAN ARPACI Rukiye Nalan TFTK Mesut TEK Kansu BÜYÜKAFAR Murat BOZLU Selahittin AYAN 《Turkish Journal of Medical Sciences》2021,49(3):1491
Background/aimThe effect of testosterone replacement therapy was investigated on bladder functions, histology, apoptosis as well as Rho-kinase expression in the rat bladder outlet obstruction (BOO) and hypogonadism models. Materials and methods30 mature male rats divided into 4 groups: sham group (n = 8), BOO group (n = 8), BOO + orchiectomy group (n = 7), BOO + orchiectomy + testosterone (T) treatment group (n = 7). Cystometric findings, apoptosis index, Rho-kinase (ROCK-2) expression, and smooth muscle/collagen ratio were compared. Results BOO did not change ROCK-2 expression level, compared to sham group (P > 0.05). However, when compared to BOO group (P < 0.01), BOO + orchiectomy led ROCK-2 increase. The testosterone treatment failed to reverse the up-regulation of ROCK-2 induced by orchiectomy although it tended to lower ROCK-2 level. Compared to sham group (P = 0.002), changes in maximal bladder capacity and leak point pressure were higher (P = 0.026, P = 0.001), and bladder compliance was lower in BOO group. Also, the apoptosis index was different between the two groups (P = 0.380). Smooth muscle/collagen ratio was higher in BOO + orchiectomy + T group than in BOO + orchiectomy group (P = 0.010).ConclusionsThe research draws attention to alternating treatment approaches in case of the presence of hypogonadism and BOO. 相似文献