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排序方式: 共有590条查询结果,搜索用时 15 毫秒
61.
62.
Aortic valve calcification: its significance and limitation as a marker for coronary artery disease 总被引:6,自引:0,他引:6
Hisar I Ileri M Yetkin E Tandoğan I Cehreli S Atak R Senen K Demirkan D 《Angiology》2002,53(2):165-169
Aortic valve calcification (AVC) is correlated with atherosclerotic risk factors; however, its significance remains largely unknown. The aim of this study was to investigate whether AVC detected by transthoracic echocardiography can be a useful marker for the identification of significant coronary artery disease (CAD), particularly in elderly patients. The study included 432 consecutive patients with suspected CAD who were admitted for the first time for coronary angiography. Two-dimensional transthoracic echocardiography and selective coronary angiography were performed in all patients. Aortic valve calcification was defined as bright dense echoes of > 1 mm on one or more cusps and decreased mobility of the involved cusp. Aortic valve calcification was detected in 64 of the 337 patients with significant CAD, but only in 9 of 95 cases with normal or mildly stenotic coronary arteries (19% vs 9%, p < 0.001). The severity of coronary artery disease (defined as the number of obstructed vessels) was not related to the presence of AVC (p > 0.05). Stepwise multiple logistic regression analysis of the study patients revealed only age (p=0.003, odds ratio= 1.56) and AVC (p<0.001, odds ratio = 2.03) as independent predictors of CAD. When the study population was divided into two groups as those below (n = 338) and above (n = 94) 75 years old, AVC failed to be a predictor of CAD in those >75 years old (p > 0.05, odds ratio = 0.8) while it remained the most significant predictor of CAD (p<0.001, odds ratio=2.19 in patients aged <75 years. In conclusion, detection of AVC by transthoracic echocardiography may be a useful noninvasive marker for identification of significant CAD in patients younger than 75 years old. Its clinical usefulness is limited in elderly patients. 相似文献
63.
Gulden Ersoz Barlas Naim Aytacoglu Nehir Sucu Lulufer Tamer Ismet Bayindir Necmi Kose Ali Kaya Murat Dikmengil 《BMC infectious diseases》2006,6(1):76
Background
Post-sternotomy mediastinitis (PSM) is a devastating surgical complication affecting 1–3% of patients that undergo cardiac surgery. Staphylococcus aureus is one of the most commonly encountered bacterial pathogen cultured from mediastinal samples obtained from patients with PSM. A component of the membrane of the gram positive bacteria, lipoteichoic acid, stimulates the blood monocytes and macrophages to secrete cytokines, radicals and nitrogen species leading to oxido-inflammatory damage. This seems to be responsible for the high mortality rate in PSM. For the evaluation of the pathogenesis of infection or for the investigation of alternative treatment models in infection, no standard model of mediastinitis seems to be available. In this study, we evaluated four mediastinitis models in rats. 相似文献64.
Baykan M Celik S Erdöl C Durmuş I Orem C Küçükosmanoğlu M Yilmaz R 《Annals of noninvasive electrocardiology》2003,8(2):101-106
Backround: P‐wave dispersion (P dispersion), defined as the difference between the maximum and the minimum P‐wave duration (P minimum), and maximum P‐wave duration (P maximum) have been used to evaluate the discontinuous propagation of sinus impulse and the prolongation of atrial conduction time respectively. The aim of this study was to investigate whether early assessment of P dispersion predicts paroxysmal atrial fibrillation (AF) in patients with acute anterior wall myocardial infarction (MI). Methods: We prospectively evaluated 147 consecutive patients (45 women, 102 men; aged 55 ± 9 years) with a first acute anterior wall MI. All patients were evaluated by echocardiography to measure the left atrial diameter and left ventricular ejection fraction (LVEF). Electrocardiography was recorded from all patients on admission and every day during hospitalization. Results: AF occurred in 25 patients. In 122 patients, AF did not occur. P maximum was found to be significantly higher in patients with AF than in patients without AF (115 ± 17.3 ms vs 101 ± 14.7 ms, P = 0.001 ). P dispersion also was significantly higher in patients with AF than in patients without AF (50 ± 12.5 ms vs 43 ± 10.1 ms, P = 0.01 ). There was no significant difference between the two groups in P minimum (64 ± 12.5 ms vs 59 ± 11.7 ms, P = 0.057 ). The echocardiographically left atrial diameters were not significantly higher in the patients with AF than those without (25 ± 3.38 mm and 23 ± 3.36 mm , respectively, P = 0.76 ). LVEF was found to be significantly different in the patients who developed AF and in those who did not (37.96 ± 6.18% vs 47.70 ± 6.01%, P = 0.0001 ). Conclusions: Although P maximum and P dispersion are significant predictive factors of AF in patients with acute anterior wall MI in the univariate analysis, on the basis of multivariate analysis, only age and LVEF were independent predictive parameters for AF. 相似文献
65.
Serum and urinary nitric oxide in Type 2 diabetes with or without microalbuminuria: relation to glomerular hyperfiltration 总被引:3,自引:0,他引:3
Apakkan Aksun S Ozmen B Ozmen D Parildar Z Senol B Habif S Mutaf I Turgan N Bayindir O 《Journal of diabetes and its complications》2003,17(6):343-348
BACKGROUND: Glomerular hyperfiltration is considered as one of the pathophysiological mechanisms for the development of diabetic nephropathy. Oxidative stress is enhanced in patients with diabetes mellitus. Reportedly, nitric oxide (NO) might be involved in the pathogenesis of hyperfiltration. We investigated the relationship between hyperfiltration and NO system, and malondialdehyde (MDA) levels in Type 2 diabetics with/without microalbuminuria. METHODS: In 39 microalbuminuric, 29 normoalbuminuric Type 2 diabetic patients and 32 healthy controls, serum creatinine, nitrite, nitrate, urinary microalbumin, nitrite, nitrate, plasma MDA and estimated glomerular filtration rate (EGFR) values, calculated according to the Cockcroft and Gault formula, were recorded. RESULTS: Serum and urine NO levels were higher in both microalbuminurics and normoalbuminurics than controls. There were no significant differences in EGFR between groups. However, hyperfiltration was determined in 31% of normoalbuminurics and 20% of microalbuminurics. Serum and urine NO levels were higher in patients with hyperfiltration. Plasma MDA levels were significantly elevated in both microalbuminurics and normoalbuminurics when compared with controls. Serum glucose and microalbuminuria were positively correlated in microalbuminuric diabetics. Serum NO levels were also positively correlated with EGFR in both normoalbuminurics and microalbuminurics. HbA1c levels were positively correlated with both urinary albumin excretion and plasma MDA levels in normoalbuminuric diabetics. CONCLUSIONS: Hyperglycemia is associated with an increased NO biosynthesis and lipid peroxidation. Increased oxidative stress may contribute to the high NO levels in Type 2 diabetes. Furthermore, the high NO levels may lead to hyperfiltration and hyperperfusion, which in turn leads to an increase in urinary albumin excretion and thus causes progression of nephropathy in early Type 2 diabetes. 相似文献
66.
67.
Summary The authors report the case of a 67-year-old woman with primary micro-invasive squamous cell carcinoma located in the lateral ventricle and originating from an epidermoid cyst. Radiological and histological features of the neoplasm are described and the relevant literature is studied briefly.Two consecutive surgical specimens were studied by light microscopy. In the histological sections of the subtotally removed material of the first operation, the cyst wall was layered by epithelium — the same as expected in an epidermoid cyst — and showed foci with mild to moderate dysplastic changes. Theses changes did not reach up to the degree of a carcinoma. However, because the cyst could not be resected totally, the possibility of a squamous cell carcinoma was considered in the differential diagnosis. In the present case, the diagnosis was firmly established in a second surgical specimen obtained ten months after the first operation. Now, the tumour proved to be a primary squamous cell carcinoma, which exhibited severe dysplastic changes.Primary squamous cell carcinoma of brain is extremely rare. To our knowledge, only 20 such tumours with pre-existing epidermoid cyst have been reported in the central nervous system. The intriguing observation in this case is a three year recurrence free survival following the subtotal removal of the malignant neoplasm at the second surgery, without postoperative radiotherapy. 相似文献
68.
Aytacoglu BN Ersoz G Sucu N Tamer L Coskun B Oguz I Bayindir I Kose N Ozeren M Dikmengil M 《Journal of chemotherapy (Florence, Italy)》2006,18(3):268-277
Post-sternotomy mediastinitis affects 1-3% of patients undergoing cardiac surgery and is lethal in 10-47% of these patients. We investigated the effect of an antioxidant/anti-inflammatory agent, caffeic acid phenethyl ester (CAPE), in the attenuation of inflammatory response induced by methicillin-resistant Staphylococcus aureus (MRSA) infection in a rat experimental mediastinitis model. Rats, divided into six equal groups, received MRSA precolonized stainless steel wire pieces implanted into their mediastinal spaces. Control group and CAPE control group received saline and CAPE 10 micromol/kg.day(-1 )respectively, where Group A received a single dose of teicoplanin 24 mg/kg i.m. for the first day and then 12 mg/kg.day(-1) . Group B received teicoplanin as in Group A plus CAPE 10 micromol/kg. day(-1 )intra-peritoneally. Group C received teicoplanin 60 mg/kg i.m. for the first day and then 30 mg/kg.day(-1 )and Group D received teicoplanin as in Group C plus CAPE 10 micromol/kg.day(-1) . By the end of 14 days rats were sacrificed and serum malondialdehyde (MDA), myeloperoxidase (MPO), nitric oxide (NO), urea and creatinine levels were evaluated. Mediastinal organ tissues were collected for histopathological analysis. Infection rates in all the drug-treated groups were lower than the control groups ( P=0.002) but statistical significance was attained only between the groups A and D ( P=0.018). In connective tissues and the peribronchial area polymorphonuclear leukocytic (PNL) infiltration in the treatment groups, although becoming very close, did not reach statistical significance (P =0.053, P=0.075, respectively). PNL infiltration especially in the peribronchial tissues of the Group B animals was found to be significantly less than the Control and CAPE Control groups with P values of 0.013 and 0.010, respectively. MDA and MPO levels were significantly lower in the treatment groups ( P<0.001 and P<0.001 respectively). Levels of the degradation products of NO were lower in treatment groups compared to two control groups (P=0.003, P= 0.005). NO levels in Group D were lowest among all treatment groups ( P=0.001). It has been demonstrated that although bacterial colonization can be controlled in mediastinitis, the inflammatory response persists. The combination of an antioxidant / anti-inflammatory agent, CAPE, added to standard antibiotic therapy might be effective in the treatment of post-sternotomy mediastinitis due to MRSA. 相似文献
69.
Cetin E Ozbek Z Saatci AO Durak I 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2006,22(5):494-499
PURPOSE: To evaluate the effect of scleral buckling surgery on corneal topography, corneal thickness, and anterior chamber depth. METHODS: Thirty-two eyes of 32 patients who underwent encircling buckling surgery for rhegmatogenous retinal detachment were included in the study. Fellow eyes comprised the control group. Orbscan II topography system was used to determine the changes in corneal topography, corneal thickness, and anterior chamber depth before surgery and 1 week, 1 month, and 3 months after surgery. Statistical analyses used in the study were independent t test, paired t test, one way analysis of variance, and correlation analyses. RESULTS: Postoperatively, mean central corneal astigmatism at 1 week, 1 month, and 3 months was 4.3 +/- 2.0 diopters (D), 3.3 +/- 1.6 D, and 3.1 +/- 1.0 D, respectively. The change between 1 week and 3 months was statistically significant. Central cornea was thickened at the first postoperative week. The thickness gradually decreased to the preoperative levels at 3 months. Anterior chamber depth decreased, and the anterior chamber remained shallow after the surgery. The comparison between preoperative (2.94 +/- 0.6 mm) and postoperative anterior chamber depth was statistically significant at 1 week (2.57 +/- 0.7 mm), 1 month (2.83 +/- 0.7 mm), and 3 months (2.73 +/- 0.6 mm). CONCLUSIONS: Corneal changes after scleral buckling surgery were mild to moderate and the cornea almost resumed its preoperative parameters in 3 months' time. However, the anterior chamber remained shallow during 3 months of follow-up. 相似文献
70.
In this study, we investigated the effects of tramadol and fentanyl on gastrointestinal transit (GIT) during acute systemic inflammation in an experimental model of cecal ligation and perforation (CLP). One-hundred-twenty male Swiss-Albino rats were divided randomly into 6 groups: Group I = sham-operated + saline; Group II = sham-operated + fentanyl; Group III = sham-operated + tramadol; Group IV = CLP + saline; Group V = CLP + fentanyl; Group VI = CLP + tramadol. Suspension of charcoal was administered as an intragastric meal to measure the GIT. GIT% (mean +/- sd) were 46.1% +/- 9.8%, 43.2% +/- 9.8%, 45.9% +/- 10.2%, 33.2% +/- 9.2%, 24.9% +/- 4.1%, and 31.8% +/- 8.4% in Groups I, II, III, IV, V, and VI, respectively. GIT% was significantly less in Group V than in Groups I, II, III, and IV (P < 0.05). The Group VI mean value was significantly lower than those of Groups I, II, and III (P < 0.05) but not different from those of Groups IV and V (P > 0.05). The antitransit effect of fentanyl was shown to have increased in the experimental sepsis model, but no decrease in GIT was obtained with tramadol. This was thought to be the result of an associated endogenic opioid system activation and receptor upregulation in sepsis. 相似文献