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31.
Venous skin flaps: an experimental study and report of two clinical distal island flaps 总被引:1,自引:0,他引:1
An experimental study of saphenous flaps in 26 dogs is reported, which confirmed the work of Baek et al. (1985) that venous flaps can survive. In addition, it showed that venous island flaps could survive after division of the venous pedicle proximally or distally, or as free flaps, providing through flow was re-established by venous anastomoses. In this study no flaps survived on a single venous pedicle without through flow. Two successful clinical cases of venous flaps are also reported, in which through flow was re-established by a simple venous anastomosis. One of these flaps threatened to become necrotic until the thrombosed anastomosis was successfully redone. 相似文献
32.
Raquel Carreira Ana Duarte Pedro Monteiro Maria Sancha Santos Ana Cristina Rego Catarina R Oliveira Lino M Gon?alves Luís A Providência 《Revista portuguesa de cardiologia》2004,23(11):1447-1455
Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore. 相似文献
33.
张振 《世界核心医学期刊文摘》2006,2(5):1-1
目的:比较儿童期癌症标准疗法与Ⅲ期随机化临床试验阶段所验证的新疗法,研究新疗法优于或劣于标准疗法的概率;此类临床试验中,纳入患者的民族因素可能对试验结果造成不确定性影响,所以,本文还研究新疗法的成功和失败模式是否与前述不确定性影响之间存在一致性。试验设计:临床观 相似文献
34.
Sandra Guerra A Teixeira Pinto José Ribeiro José Oliveira José Duarte Jorge Mota 《Revista portuguesa de cardiologia》2003,22(2):167-182
An important aspect of preventive medicine is to identify subjects at risk as soon as possible, so preventive strategies can be introduced at early ages. The justification for this strategy is twofold: firstly, the assumption that children maintain a particular high value of a risk factor for disease throughout life; and secondly, the assumption that lowering the level of the risk factor in early life will have a greater impact on the disease than will risk factor changes in later life. In epidemiology the analysis of such factors over time is referred to as tracking. Tracking analysis has been applied to risk factors for cardiovascular diseases (CVD) in pediatric years. The aims of this study were: I) to analyze the stability of biological risk factors [high blood pressure (BP), high percentage of fat mass (%FM) and high total cholesterol (TC)] and lifestyle risk factors [low physical activity index (PAI)] in isolation; and II) to analyze the stability of zero, one, two or three biological risk factors. There were two evaluations in 692 children and adolescents (325 boys and 367 girls), aged between 8 and 15 years. The quartiles, adjusted for age and gender, were the criterion used to identify subjects with biological risk factors (fourth quartile) and with lifestyle risk factors (first quartile) for CVD. The stability was calculated through the relative frequency of subjects who maintained or changed quartile between the two evaluations. There is stability for biological risk factors as well as for behavioral and/or lifestyle risk factors. However, the highest stability is seen in biological risk factors. 相似文献
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37.
Ultrastructural aspects ofTrypanosoma (Megatrypanum) freitasi in co-cultivation with mammalian cells
Neide Thomaz Maurílio J. Soares Wanderley de Souza Maria P. Deane 《Parasitology research》1992,78(3):209-214
Cultures ofTrypanosoma (Megatrypanum) freitasi with L929 mouse fibroblasts at 27.5°C were examined by scanning and transmission electron microscopy in an attempt to clarify the processes of colony formation by the epimastigotes and of their attachment to substrata. It was seen that the flagellates occupy intercellular spaces and do not associate with intact fibroblasts. As the trypanosome population increases, ever larger portions of the substratum are cleared of fibroblasts and occupied by conglomerates of epimastigote colonies consisting of about a dozen organisms that attach to the substratum by their anterior extremities and form pyramidal clusters. Attachment of the epimastigotes involves the flagellar membrane, which becomes extraordinarily enlarged and assumes various aspects of broad sheets, filaments and loops over the substratum or along the flagellum, which exhibits a shortened axoneme. Desmosome or hemidesmosome plaques are present when the attachment takes place between membranes or between the membrane and the substratum.Supported by grants from CNPq and FINEP 相似文献
38.
Claudio N Soares Brian J Murray 《Psychiatric Clinics of North America》2006,29(4):1095-113; abstract xi
Sleep disorders are more prevalent in women than in men. Sex hormones modulate sleep-wake behaviors and mood and may contribute to heightened risk across the life cycle of women. Sleep disorders may have a unique expression in women, emerging throughout their reproductive life cycle. These conditions require careful treatment strategy to manage medical, hormonal, and behavioral contributing factors to poor sleep efficiency and impaired quality of life. This review focuses on clinical evidence for sleep disorders in women and discusses existing evidence of risk factors and treatment options for insomnia and sleep-disordered breathing in women. 相似文献
39.
D.R. Pina S.B. Duarte J. Morceli T. Ghilardi Netto 《Applied radiation and isotopes》2006,64(12):1623-1630
We present the construction of a homogeneous phantom to be used in simulating the scattering and absorption of X-rays by a standard patient chest and skull when irradiated laterally. This phantom consisted of lucite and aluminium plates with their thickness determined by a tomographic exploratory method applied to the anthropomorphic phantom. Using this phantom, an optimized radiographic technique was established for chest and skull of standard sized patient in lateral view. Images generated with this optimized technique demonstrated improved image quality and reduced radiation doses. 相似文献
40.
A de O Soares 《Revista portuguesa de cardiologia》1992,11(2):185-190
In this oral presentation, the author emphasized the need for individualization of drug treatment, reviewing the most known factors of variability in drug response. The importance of studies of clinical pharmacokinetics was focused. The main parameters for a judgement on the efficacy and virtual tolerability of a medicine, on the basis of its sequential concentrations in the blood after administration, were briefly outlined. The influence of congestive heart failure on the volume of distribution, systemic clearance, elimination half-life and bioavailability, was discussed. The changes that renal failure makes in drug elimination were equally presented, having been pointed the modification of protein binding, volume of distribution, and hepatic elimination. A selection of eight clinical cases was summarily presented, to illustrate the important contribute that can be afforded to practice by pharmacokinetics. The dosing of aminoglycosides and of other drugs with narrow therapeutic ranges was evaluated through some of the examples. A case of complex interferences of heart failure, renal failure and therapeutic hemoperfusion on the kinetics of an antibiotic drug was included. Two cases of intoxications (phenytoin and theophylline), whose management has been greatly improved by repeated drug dosing in blood, were discussed, too. A special call of attention was made to the need the currently practicing physician has of being aware of kinetic characteristics of the drugs he prescribes, and of how can disease modify the body fate of those medicines, and their therapeutic and nontherapeutic effects. 相似文献