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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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Yusuf E. Karakullukçu Tayfun Özçelik Nuran Gökhan 《Pflügers Archiv : European journal of physiology》1987,410(6):657-663
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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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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P. N. Robinson A. Shaikh N. M. Sabir D. J. A. Vaughan M. Kynoch M. Hasan 《Anaesthesia》2014,69(7):707-711
The Tulip® airway is an adult, disposable, single‐sized oropharyngeal airway, that is connectable to an anaesthetic circuit. After a standardised induction of anaesthesia in 75 patients, the ease of insertion, intracuff pressure and intracuff volume were measured, as were the end‐tidal carbon dioxide levels, airway pressures and tidal volumes over three breaths. Successful first‐time insertion was achieved in 72 patients (96%, CI 88.8–99.2%) and after two attempts in 74 patients (99%, CI 92.8–100%). There was outright failure only in one patient. In 60 patients (80%, CI 72.2–90.4%), the Tulip airway provided a patent airway without additional manoeuvres, but in 14 patients, jaw thrust or head extension was necessary for airway patency. The main need for these adjuncts appeared to be an initial under‐inflation of the cuff. These promising results are consistent with recent manikin studies using this device. 相似文献
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