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91.
Davide Pacini Emmanuel Villa Sofia Martin-Suarez Roberto Di Bartolomeo 《European journal of cardio-thoracic surgery》2005,27(4):717-719
Patients who underwent isolated aortic valve replacement could come to attention for new onset aortic disease or progression of borderline alterations not corrected at the first operation, especially in the subset of bicuspid valve disease. We describe our technique in redo operations for aortic root disease, using only a vascular graft and sparing the previously implanted valve prosthesis. In case of normally functioning mechanical prosthesis, we always left the valve in situ and substituted the aortic root with a Dacron conduit, extending the replacement if necessary to the other diseased portions of the thoracic aorta. 相似文献
92.
Marcos Barbosa-Ferreira Maria Lúcia Zaidan Dagli Paulo César Maiorka Silvana Lima Górniak 《Food and chemical toxicology》2005,43(4):497-503
Senna occidentalis (So) is a weed that grows in pastures along fences and in fields cultivated with cereals such as corn and soybean, and many reports have been showing intoxication with this plant in different animal species. It is also used in many medicinal purposes. The objective of the present study was to better evaluate the toxic effects of prolonged administration of So seeds to rats. Forty male Wistar rats were divided into four groups of 10 animals each, three of them respectively fed rations containing 1%, 2% and 4% So seeds, and the last one (control) fed commercial ration for a period of 2 weeks. Fourteen rats were also used in a pair-feeding (PF) experiment. The rats of the experimental groups showed lethargy, weakness, recumbency, depression and emaciation. Two rats of the 4% group and two of the PF group died during the experiment. Histopathological study showed fiber degenerations in the skeletal (Tibial, pectoral and diaphragm) and cardiac muscles. In the liver parenchyma, was observed vacuolar degeneration and, in the kidney, mild nefrosis in the proximal convoluted tubules. All of these alterations occurred in a dose-dependent fashion. Moderate to severe degeneration and spongiosis in the central nervous system, especially in cerebellum. Electron microscopy revealed mitochondrial lesions in all analyzed tissues. 相似文献
93.
Karina M S Freitas Marcos Roberto de Freitas José Fernando Castanha Henriques Arnaldo Pinzan Guilherme Janson 《American journal of orthodontics and dentofacial orthopedics》2004,125(4):480-487
Treatment stability is one of the most important objectives in orthodontics, but, despite decades of research, it is still agreed that the stability of aligned teeth is variable and largely unpredictable. This study aimed to evaluate the relapse of mandibular anterior crowding in patients treated without mandibular premolar extraction. The sample comprised 40 patients of both sexes with Class I or II malocclusions who received nonextraction treatment in the mandibular arch with edgewise mechanics. Lateral cephalograms and dental casts of each patient were obtained at pretreament, posttreatment, and 5 years postretention. Relapse of mandibular anterior crowding was assessed, and associations between this relapse and other clinical factors were also investigated. Mandibular anterior crowding was measured by the Little irregularity index, and the data were evaluated by the Mann-Whitney test. The mean relapse of mandibular anterior crowding was 1.95 mm (26.54%) over the long term. No clinical factor studied was predictive of crowding relapse in the long term. 相似文献
94.
Robert Willer Farinazzo Vitral Carlos de Souza Telles Marcelo Reis Fraga Roberto Sotto Maior Fortes de Oliveira Orlando Motohiro Tanaka 《American journal of orthodontics and dentofacial orthopedics》2004,126(1):48-52
Thirty persons with Class II Division 1 subdivision malocclusions, ranging in age from 12 years 8 months to 42 years, underwent computed tomography of the temporomandibular joints. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, the condyle-fossa relationship, and the concentric position of the condyles associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations (r) were determined after measurements on both Class I and Class II sides were obtained. No statistically significant asymmetries were found in the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, or the condyle-fossa relationship. However, a statistically significant (P <.05) anterior positioning of the condyles was observed. 相似文献
95.
Miguel Marcos Alex Soriano José A Martínez Josep Mensa 《Clinical infectious diseases》2007,45(10):1401; author reply 1401-1401; author reply 1402
96.
Davicino Roberto Patricia Micucci Turner Sebastian Ferraro Graciela Claudia Anesini 《Basic & clinical pharmacology & toxicology》2010,106(1):38-44
Abstract: Limonene is a monoterpene present in citrus fruit and is used as flavouring agents of foods. It was shown that monoterpenes possess antioxidant activity. Previously, it was demonstrated that limonene exerts anti‐proliferative action on a lymphoma cell line without modifying normal lymphocyte viability. H2O2 has a modulator role in cell proliferation. In the present study, the effect of limonene on normal lymphocytes proliferation and its relation with H2O2 level modulation was analysed, evaluating its effect on the activity of cell antioxidant enzymes, such as catalase, peroxidase and superoxide dismutase. Limonene exerted a biphasic effect on cell proliferation; the increase in cell proliferation was related to the decrease in H2O2 level by the increase in catalase and peroxidase activities. Moreover, limonene protected the cells to the oxidative stress induced by exogenous addition of H2O2. In view of these results, it is possible that limonene could protect normal lymphocytes from diseases related to oxidative stress, including cancer, but further research is necessary to establish the role of limonene as a potential antioxidant that can effectively protect lymphocytes from oxidative stress and mitochondrial dysfunction. 相似文献
97.
Permeability of pure lipid bilayers to melatonin 总被引:9,自引:1,他引:8
Ernane J.X. Costa Roberto Harzer Lopes M. Teresa Lamy-Freund 《Journal of pineal research》1995,19(3):123-126
Abstract: Melatonin, the chief hormone of the pineal gland, has been reported to interact with a variety of different cells. This ubiquitously acting hormone has been found to interact with protein receptors both at the cell membrane and in the nucleus. Moreover, melatonin was recently shown to be a very potent hydroxyl radical scavenger. The present work focuses on the interaction of melatonin with pure lipid bilayers. It is shown that melatonin can cross multilamellar lipid vesicles, which are used here as model systems for the lipid phase of biological membranes. Thus, the data prove that melatonin can easily pass through the cell membrane and bath every part of the cell, as previously suggested in the literature. Melatonin lipid association constant was calculated based on the change of the hormone fluorescence intensity due to its penetration into the hydrophobic lipid phase. Though melatonin was recently shown to be highly soluble in aqueous media, its lipid association constant is rather high, indicating that the biological action of the hormone is likely to be at the membrane level, either via its interaction with membrane receptors, and/or as a lipoperoxidation radical scavenger. 相似文献
98.
Summary: A survey of the medical records and renal biopsy reports of 41 patients with a diagnosis of membranous glomerulonephritis seen at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo was undertaken between 1961 and April 1992. Twenty-three of these patients were found to have idiopathic membranous glomerulonephritis (IMG) and 22 of them were treated with corticosteroids and/or immunosuppressants. Data for these 22 patients showed that the age at clinical presentation was 36.3± 17.5 years, white skin colour predominated (14 patients), and 15 were males; nephrotic syndrome was the clinical presentation in 20 patients and proteinuria was accidentally discovered in two patients. On the first hospital visit 11 patients presented proteinuria of up to 3 g/24 h and 16 presented serum creatinine below 1.5 mg/dL, and 14 developed renal hypertension during follow up. Clinicalmorphological correlation permitted us to conclude (in agreement with the literature) that advanced patient age, intensity of proteinuria, serum creatinine levels above 1.5 mg/dL on the occasion of the first hospital visit, and arterial hypertension are clinical-laboratory factors indicating a poor prognosis for IMG. More advanced staging of glomerular damage, presence of segmental mesangial sclerosis and tubulointerstitial involvement are microscopic factors indicating a poor prognosis for IMG. 相似文献
99.
Maria De Ftima V. Marques Cristiane A. Henriques Jos Luiz F. Monteiro Sonia M. C. Menezes Fernanda M. B. Coutinho 《Macromolecular chemistry and physics.》1997,198(11):3709-3717
Y zeolites with different sodium contents and a sodium mordenite were evaluated as support for bis(cyclopentadienyl)zirconium dichloride as catalyst for ethylene polymerization. The results showed that, although the activities of the supported catalysts were lower than that of the homogeneous system, the average molecular weight of the polyethylene produced from the former was in general much higher than that of the polymer produced in solution. Contrary to the expected trend if the specific area was the dominant factor for catalyst activity, the best catalyst was the one supported on NaM zeolite. Thus, our results indicate that the concentration of framework aluminium atoms is the dominant factor, but that the contribution of the external surface is also important. 相似文献