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Kaplan C  Diril N  Sahin S  Cehreli MC 《Biomaterials》2004,25(18):4019-4027
The potential mutagenicity of a zinc phosphate (Poscal), a polycarboxylate (Aqualox) and glass ionomer cements with (Argion) and without (Meron) silver reinforcement were characterized by employing the Ames Salmonella/microsome test. The materials were eluted in dimethyl sulphoxide or physiologic saline and the aliquots were used either immediately or after an incubation period of 24h at 37 degrees C. Mutagenic effects of the materials were tested on Salmonella typhimurium strains TA 98, TA 100, TA 102 and TA 1535 using the standard plate incorporation assay, and in the presence or absence of S9 fraction from rat liver. Poscal and Aqualox elicited mutagenic effects on S. typhimurium TA 98 and TA 1535, whereas Meron exhibited mutagenic effects on S. typhimurium TA 98. No mutagenic effects were detected for Argion. The type of solvent, dose of the material and incubation as well as the interactions between these factors exhibited varying degrees of influences on the mutagenic activities of the cements (P<0.05 and P<0.1). We conclude that zinc phosphate, polycarboxylate, and glass ionomer cements may have possible mutagenic activities.  相似文献   
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Reperfusion of hearts with a Ca2+-containing medium after a perfusion period in Ca2+-free medium results in irreversible cell damage (calcium paradox). In this investigation we have studied coronary flow and cyclic AMP and cyclic GMP levels after several periods of Ca2+-free perfusion in isolated rat hearts. We also investigated the effects of papaverine (Pap), noradrenaline (NA), acetylcholine (ACh) and absence of inorganic phosphate during Ca2+-free perfusion on coronary flow (CF) and cyclic nucleotide levels. Inability of the heart to recover contractile activity with development of contracture during the reperfusion period was accepted as indicative of the calcium paradox. Ca2+-free perfusion alone and NA and absence of inorganic phosphate during the Ca2+-free perfusion period increased CF, whereas Pap and ACh decreased it. However, only Ca2+-free perfusion and NA elevated cyclic AMP. On the other hand, Pap and ACh increased cyclic GMP (with a transient rise of cyclic AMP in Pap infusion), and absence of inorganic phosphate decreased both cyclic AMP and cyclic GMP. Pap, ACh and absence of phosphate prevented the calcium paradox. Our study suggests that increased cyclic AMP during the Ca2+-free perfusion may contribute, with the other factors, to the occurrence of the calcium paradox.  相似文献   
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Two techniques for labeling of albumin with copper-67 (67Cu) and 62Cu were investigated; one using the native Cu(II) binding site of the protein and the other employing a bifunctional chelate, 6-bromoacetamidobenzyl-1,4,8,11-tetraazacyclotetradecane- N,N'N",N"'-tetraacetic acid (Br-benzyl-TETA or BAT), conjugated to the protein. Rat biodistribution experiments with 67Cu demonstrated retention of i.v. 67Cu-benzyl-TETA-albumin in the blood pool identical to co-injected 125I-albumin. By contrast, i.v. administration of either [67Cu]-Cu-acetate or [67Cu]-Cu-acetate pre-mixed with albumin results in relatively rapid clearance of blood-pool radioactivity as the tracer is excreted into the urine. The 62Cu-benzyl-TETA-albumin radiopharmaceutical was obtained in ca. 17% radiochemical yield (end of synthesis, without decay correction) following a procedure that can be completed in 15-18 min. In PET experiments with a baboon, myocardial blood volume images with 62Cu-benzyl-TETA-albumin were identical to those obtained with C15O. Use of the 62Cu-benzyl-TETA-albumin image for blood-pool subtraction of a 62Cu-PTSM myocardial perfusion image is illustrated. Copper-62-benzyl-TETA-HSA should be a useful, generator-produced radiotracer for the detection of the vascular pool at PET facilities without cyclotrons.  相似文献   
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BackgroundPsoriasis is a chronic skin disease that can have severe psychosocial effects. The aim of this study was to assess the perspectives of psoriasis patients regarding their illness.MethodsOne hundred and ten psoriasis patients in the 18–65 age group were included. Data were collected via a “face to face interview” method. The questionnaire included mainly three topics (socio-demographic characteristics of patients; self-evaluations of patients about their disease; knowledge and attitudes about psoriasis).ResultsThe majority of the patients stated that psoriasis as a socially troubling disease. Almost half of them believed that “stress and unhappiness” was a predisposing factor of their illness. Belief that the occurrence of the disease was due to a contagious infectious agent was the second most frequent factor that patients emphasized. “Signs and symptoms of psoriasis” was the most frequent difficulty patients faced because of psoriasis. Most of the patients who still have their parents, those who have a closest friend in life, and more than half of the patients who have their closest friend at work all stated that there was a change in social relations, mostly arising from their counterparts. More than half of the married patients stated that there was a change in social relations, mostly arising from their spouses.ConclusionPsoriasis is more than a cosmetic nuisance and can be associated with psychosocial effects that seriously affect patients’ lives and social relations. Increasing the patients’ knowledge of the disease could have a positive effect on the relations the psoriasis patients have within their social environment.  相似文献   
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Background: The widespread use of percutaneous mitral commissurotomy (PMC) has led to an increase in restenosis cases. The data regarding follow‐up results of repeat PMC are quite limited. The aim of this retrospective analysis is to evaluate the immediate and midterm results of the second PMC, in patients with symptomatic mitral restenosis after a succesful first procedure. Methods: Twenty patients (95% female, mean age 37 ± 4 years) who have undergone a second PMC, 6.3 ± 2.5 years after a first successful intervention built the study group. All were in sinus rhythm, with a mean Wilkins score of 8.5 ± 1.2. Results: The valve area increased from 1.2 ± 0.2 to 1.9 ± 0.2 cm2 and mean gradient decreased from 10.5 ± 3.4 to 6.1 ± 1.1 mmHg. There were no complications except for a transient embolic event without sequela (5%) and two cases (10%) of severe mitral regurgitation. The immediate success rate was 90%. The mean follow‐up was 70 ± 29 months (36–156 months). The 5‐year restenosis and intervention (repeat PMC or valve replacement) rates were 9.1 ± 5.2% and 3.6 ± 3.3%, respectively. The intervention free 5‐year survival in good functional capacity (New York Heart Association [NYHA] I–II) was 95.1 ± 5.5% and restenosis and intervention free 5‐year survival with good functional capacity was 89.7 ± 6.8%. Conclusions: Although from a limited number of selected patients, these findings indicate that repeat PMC is a safe and effective method, with follow‐up results similar to a first intervention and should be considered as the first therapeutic option in suitable patients. (Echocardiography 2010;27:765‐769)  相似文献   
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Isotretinoin (Iso) is the most effective drug against severe nodulocystic acne. As a synthetic oral retinoid, Iso exerts its actions by modulating cell growth and differentiation. Targeting all the pathophysiologic processes in acne development, Iso has been considered to be an unique drug, however it has several side effects. While chelitis, xerosis, ocular sicca, arthralgia, myalgia, headache, hyperlipidemia are the most common side effects, teratogenicity and depressive symptoms are the most concerning ones. In addition, Iso has unusual side effects which have been described for the first time in the literature. Here, we report a remarkable side effect of Iso in a 23-years-old male patient with retinoid dermatitis affecting the external uretral meatus. To our knowledge, only few cases of retinoid dermatitis in the urethral mucosa due to Iso have been reported in the literature so far.  相似文献   
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Metabolic Brain Disease - Gaucher disease type 2 is the most progressive and the rarest form of Gaucher disease, defined as the acute neuronopathic type. We presented two GD2 patients who died...  相似文献   
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