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81.
Kayan M Köroğlu M Yeşildağ A Ceylan E Aktaş AR Yasar S Aynali G Parlak C Munduz M Gürses C 《European journal of radiology》2012,81(9):2144-2147
Availability and utilization of computed tomography angiography has been increasing recently. We aimed to assess the effectiveness of low amount of contrast media and low kV value in order to reduce possible side effects of contrast media and to provide optimization of kV value in the evaluation of the carotid artery with multi-detector computed tomography angiography. Forty one patients were randomized into two groups. Contrast media was administered at a dose of 1 ml/kg in group A patients and of 0.5 ml/kg in group B patients. kV value of 120 in group A and 100 in group B were chosen. Bolus tracking technique was used. Attenuation values of certain arterial segments were measured, and values over 200 HU were considered as significant. North American Symptomatic Carotid Endartherectomy Trial criteria were utilized in the evaluation of stenosis. Image quality in arterial segments of all cases was found to be sufficient for diagnosis. Arterial attenuation values were found to be higher in group B than group A. When compared separately in all arterial segments, there was no statistically significant difference between the groups. For stenosis, 615 arterial segments were evaluated. Moderate stenosis in eight segments and severe stenosis in three segments were identified in group A. Occlusion in three segments, severe stenosis in three segments, and moderate stenosis in 25 segments were detected in group B. Better image quality can be obtained, and the amount of contrast media can be reduced using low kV technique in carotid artery multi-detector computed tomography angiography examination. 相似文献
82.
Perioperative vasospasm during cardiovascular surgery is a challenging problem. Several vasodilator agents are frequently utilized for its prevention in surgical practice. Magnesium and diltiazem both have known potential vasorelaxant effects. We planned to compare the efficacy of diltiazem and magnesium in relieving phenylephrine-precontracted rat aortic rings. Ten young adult female Wistar albino rats weighing 230-260 g were used in this study. The aortic rings in the organ bath equilibrated and reached their baseline tension. Precontraction was induced by 0.001 mmol/l phenylephrine and cumulative concentration-relaxation curves were obtained by consecutively increasing the addition of either diltiazem (10(-6)-0.1 mmol/l) or magnesium (0.1-10 mmol/l). The mean maximal relaxation responses observed by diltiazem and magnesium on separate aortic rings were 90 ± 3 and 53 ± 2%, respectively. The calculated EC50 of diltiazem was 0.01035 mmol/l, whereas the EC50 of magnesium was 4.064 mmol/l (P < 0.05). Both magnesium and diltiazem produced vasorelaxation on phenylephrine-precontracted rat aortic rings in this study, but the potency of diltiazem regarding the EC50 value was significantly higher than that of magnesium. Magnesium could be a candidate together with diltiazem to inhibit vasospasm on arterial grafts during coronary bypass surgery. 相似文献
83.
Eker HH Bayraktarli RY Işsever H Ulaş T Erelel M Eser AI Özdilli K Özder A 《International journal of occupational medicine and environmental health》2012,25(1):14-21
Objectives
This study aims to assess the frequency and factors relevant to metabolic syndrome in workers employed in the collection and disposal of solid waste sector. 相似文献84.
85.
86.
Sel?uk Kaya Recep Süt?ü Emel Sesli Cetin Buket Cicioglu Aridogan Namik Deliba? Mustafa Demirci 《International journal of infectious diseases》2007,11(3):251-255
OBJECTIVE: In this study, we investigated the relationship between fascioliasis and serum malondialdehyde (MDA) levels, superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx) activities. We also investigated whether there are significant differences in MDA levels and antioxidant enzymatic activities between acute and chronic fascioliasis. METHODS: Forty fascioliasis patients who were diagnosed by ES-ELISA positivity were included in this study. The patients were classified as 18 with acute and 22 with chronic fascioliasis. RESULTS: In patients with fascioliasis, levels of MDA were statistically higher and erythrocyte SOD and GPx activities were statistically lower than in healthy controls. MDA levels were found to be higher in patients with acute fascioliasis than in patients with chronic fascioliasis although MDA levels were significantly higher in patients with chronic fascioliasis than in controls. There was no statistically significant difference between the two groups for the antioxidant enzyme activities. CONCLUSION: The results of this study may indicate that fascioliasis produces specific effects on the antioxidant defense mechanisms due to its inflammatory character. Our results also allow us to suggest that oxidative stress has an important role in the pathogenesis of fascioliasis and the persistence of this oxidative stress can be one of the underlying factors in the pathogenesis of the chronic disease. 相似文献
87.
88.
Background
Intraoperative penile erections following the initiation of either regional or general anaesthesia is rare; however, when it occurs in patients undergoing urologic procedures it may delay, or even cancel the planned surgery. The aetiology is unclear. Various treatments proposed for producing detumescence are not always effective. Use of intracavernous alpha-adrenergic agonists is an efficient and rapid but short-lasting treatment. Furthermore, repeated intracavernous injections of vasoactive drugs may be harmful. Dexmedetomidine is a potent, selective α2-adrenoreceptor agonist. In our study, we evaluated the effect of dexmedetomidine on intraoperative penile erection. 相似文献89.
Sergio E. Chiarella Saul Soberanes Daniela Urich Luisa Morales-Nebreda Recep Nigdelioglu David Green James B. Young Angel Gonzalez Carmen Rosario Alexander V. Misharin Andrew J. Ghio Richard G. Wunderink Helen K. Donnelly Kathryn A. Radigan Harris Perlman Navdeep S. Chandel G.R. Scott Budinger G?khan M. Mutlu 《The Journal of clinical investigation》2014,124(7):2935-2946
Acute exposure to particulate matter (PM) air pollution causes thrombotic cardiovascular events, leading to increased mortality rates; however, the link between PM and cardiovascular dysfunction is not completely understood. We have previously shown that the release of IL-6 from alveolar macrophages is required for a prothrombotic state and acceleration of thrombosis following exposure to PM. Here, we determined that PM exposure results in the systemic release of catecholamines, which engage the β2-adrenergic receptor (β2AR) on murine alveolar macrophages and augment the release of IL-6. In mice, β2AR signaling promoted the development of a prothrombotic state that was sufficient to accelerate arterial thrombosis. In primary human alveolar macrophages, administration of a β2AR agonist augmented IL-6 release, while the addition of a beta blocker inhibited PM-induced IL-6 release. Genetic loss or pharmacologic inhibition of the β2AR on murine alveolar macrophages attenuated PM-induced IL-6 release and prothrombotic state. Furthermore, exogenous β2AR agonist therapy further augmented these responses in alveolar macrophages through generation of mitochondrial ROS and subsequent increase of adenylyl cyclase activity. Together, these results link the activation of the sympathetic nervous system by β2AR signaling with metabolism, lung inflammation, and an enhanced susceptibility to thrombotic cardiovascular events. 相似文献
90.
İlker Durak Recep Çetin Özden Çandır Erdinç Devrim Bülent Kılıçoğlu Aslıhan Avcı 《Immunological investigations》2013,42(1):105-114
The aim of this study was to determine if the natural antioxidant foods, dried black grape and garlic, protect against cyclosporine nephrotoxicity. Forty-two Sprague–Dawley rats were given Cyclosporine A (CsA) orally for 10 days, with the antioxidant food supplementation begun 3 days before CsA treatment and continued during the study period (totaling 13 days). In each group (control, CsA alone, CsA plus black grape, CsA plus aqueous garlic extract, aqueous garlic extract alone and black grape alone), there were 7 animals. At the end of the study period, the animals were sacrificed; their kidneys were removed and prepared for biochemical and histopathological investigations. Oxidant (xanthine oxidase enzyme and malondialdehyde) and antioxidant (superoxide dismutase, glutathione peroxidase and catalase enzymes) parameters were measured in the kidney tissues of the groups. Histopathological examinations of the tissues were also performed.It has been found that CsA creates oxidant load to the kidneys through both xanthine oxidase activation and impaired antioxidant defense system, which accelerates oxidation reactions in the kidney tissue. Supplementation with either dried black grape or aqueous garlic extract led to reduced malondialdehyde level in the kidney tissue possibly, by preventing oxidant reactions. In conclusion, the results suggest that impaired oxidant/antioxidant balance may play part in the CsA-induced nephrotoxicity, and some foods with high antioxidant power may ameliorate this toxicity, in agreement with studies with antioxidant vitamins. 相似文献