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81.
Manuel Diaz-Llopis Salvador García-Delpech David Salom Patricia Udaondo Francisco Bosch-Morell Arturo Quijada Francisco J Romero Luis Amselem 《Journal of ocular pharmacology and therapeutics》2007,23(4):343-350
PURPOSE: The aim of this study to analyze the preventive effect of high-dose infliximab in endotoxin-induced uveitis (EIU) in rabbits. METHODS: An experimental study was conducted on 64 rabbits. Salmonella typhimurium lipopolysaccharide endotoxin was intravitreally injected. Infliximab was intravenously (i.v.) injected 24 h before the intravitreal injection (20 mg/kg). The animals were randomly assigned to five groups: group A, saline intravitreal injection; group B, Infliximab i.v. group C, infliximab + saline; group D, intravitreal endotoxin and group E, infliximab i.v. + intravitreal endotoxin. With two masked observers, a microscopic examination of aqueous humor (cells, tumor necrosis factor [TNF] alpha) and aqueous protein level were performed 24 h after an endotoxin injection and 48 h after an infliximab infusion. RESULTS: Infliximab treatment, at a dose of 20 mg/kg, significantly improved all the parameters. Inflammatory cell infiltration was significantly reduced in the iris, ciliary body, and anterior chamber (U Mann-Whitney test, P = 0.01). Associated with a lower level of TNF-alpha and protein exudate in aqueous humor (U Mann-Whitney test, P = 0.01). CONCLUSIONS: Infliximab, at a dose of 20 mg/kg, is effective in the prophylaxis of the EIU. 相似文献
82.
83.
J. Francisco Salomão Sérgio Cavalheiro Hamilton Matushita René D. Leibinger Antonio R. Bellas Elide Vanazzi Luiz A. M. de Souza Andréa G. Nardi 《Child's nervous system》2006,22(3):234-242
Background Cystic dysraphic lesions of the cervical and upper thoracic region are rare and only a few series have been published about the topic. These malformations can be divided into categories that include both myelocystoceles and the so-called cervical meningoceles or myelomeningoceles.Methods A retrospective study of 18 patients was conducted.Results In 17 patients a squamous or a cicatricial epithelium of variable thickness covered the dome of the lesions, while the base was covered with full-thickness skin. In one case the skin was entirely normal. Four patients displayed associated CNS malformations and three more had systemic congenital anomalies. All patients underwent surgical exploration and the length of time between birth and surgery ranged from 6 h to 9 months. The most frequent surgical finding, seen in 14 patients, was a stalk connecting the dorsal surface of the spinal cord to the cyst. In three patients the findings were consistent with myelocystocele. Only in one case was a true meningocele found. Hydrocephalus and Chiari II malformation were not as consistently associated as in myelomeningoceles. Neurological signs and symptoms were not so marked as in myelomeningoceles and were found in the follow-up of four patients. In two of them there was a non-progressive deficit, probably expressing an imperceptible involvement of the nervous system in the first year of life. The histopathological findings were of three types: neuroglial stalks, fibrovascular stalks and myelocystoceles.Conclusions Cystic dysraphisms of the cervical and upper thoracic region differ clinically and structurally from meningomyelocele and have a more favorable outcome. We believe that these malformations have not been properly labeled and propose a classification based on the structures found inside the cyst. 相似文献
84.
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
85.
86.
Jos A. Terrn Enrique Hong Francisco J. Lpez-Muoz Carlos M. Villaln 《Autonomic & autacoid pharmacology》1994,14(3):165-175
1 The present study was designed to analyse the effect of the centrally-acting sympatho-inhibitory drugs, prazosin and ketanserin, on the increase in external carotid blood flow (external CBF) produced by 5-hydroxytryptamine (5-HT) in pentobarbital-anaesthetized dogs. 2 Intracarotid (i.c.) infusions of 5-HT (10 μ g min?1 during 1 min) produced an increase in external CBF without changes in mean arterial blood pressure or heart rate. This response to 5-HT was dose-dependently blocked by intravenous (i.v.) administration of prazosin (1, 3, 10, 30 and 100 μg kg?1) or ketanserin (10, 30, 100 and 300 μg kg?1). 3 Furthermore, 5-HT-induced increase in external CBF was inhibited by either the ganglionic blocking agent, mecamylamine (0.03, 0.1, 0.3, 1, 3 and 10 mg kg?1), the mixed 5-HT1-like and 5-HT2 receptor antagonist, methiothepin (3, 10 and 30 μ g kg?1) or the 5-HT1A ligand, spiroxatrine (10, 30, 100 and 300 μg kg?1). In contrast, the selective 5-HT2 and 5-HT1C receptor antagonist, ritanserin (30 and 100 μg kg?1, i.v.), was unable to block the above response to 5-HT. 4 It is concluded that the inhibition of 5-HT-induced increase in external CBF by prazosin, ketanserin, mecamylamine and spiroxatrine is due to a reduction in the sympathetic tone and not to a blockade of 5-HT receptors. 相似文献
87.
John L. Adams Matthias Schonlau José J. Escarce Meredith Kilgore Michael Schoenbaum Dana P. Goldman 《Health services & outcomes research methodology》2003,4(3):151-167
In order to better inform study design decisions when sampling patients within and across health care providers we develop a simulation-based approach for designing complex multi-stage samples. The approach explores the tradeoff between competing design goals such as precision of estimates, coverage of the target population and cost.We elicit a number of sensible candidate designs, evaluate these designs with respect to multiple sampling goals, investigate their tradeoffs, and identify the design that is the best compromise among all goals. This approach recognizes that, in the practice of sampling, precision of the estimates is not the only important goal, and that there are tradeoffs with coverage and cost that should be explicitly considered. One can easily add other goals. We construct a sample frame with all phase III clinical cancer treatment trials that are conducted by cooperative oncology groups of the National Cancer Institute from October 1, 1998 through December 31, 1999. Simulation results for our study suggest sampling a different number of trials and institutions than initially considered.Simulations of different study designs can uncover efficiency gains both in terms of improved precision of the estimates and in terms of improved coverage of the target population. Simulations enable us to explore the tradeoffs between competing sampling goals and to quantify these efficiency gains. This is true even for complex designs where the stages are not strictly nested in one another. 相似文献
88.
Thomas Patrick S. Jr; Fraley Gregory S.; Damian Vincent; Woodke Lillie B.; Zapata Francisco; Sopher Bryce L.; Plymate Stephen R.; La Spada Albert R. 《Human molecular genetics》2006,15(19):2972
Human Molecular 相似文献
89.
Lucia Carvalho Monica Lipay Francisco Belfort Ivan Santos Joyce Andrade Alessandra Haddad Flavia Brunstein Lydia Ferreira 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):961-968
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours. 相似文献
90.
Magdalena Sanz-Cortés Víctor Martín González Francisco Raga Baixauli Fernando Bonilla-Musoles 《Progresos de Obstetricia y Ginecología》2006
We report the case of a patient with synchronous neoplasms of the endometrium and ovary, which developed at a relatively young age (45 years). Clinical presentation consisted of hypermenorrhea. An ovarian tumor was subsequently detected through ultrasound and computed tomography. Pathological examination revealed endometrioid histology at both sites and, as in most synchronous tumors occurring in these locations, both the grade and the stage of the tumors were low. All these factors indicate a good prognosis. 相似文献