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31.
Jack Yamuy John K. Engelhardt Francisco R. Morales Michael H. Chase 《Brain research》1992,570(1-2):300-306
The objective of this study was to determine whether the aging process influences the changes in the electrophysiological properties of motoneurons that occur as a consequence of axotomy. Accordingly, using intracellular recording and stimulating techniques, the basic electrical properties of control (unaxotomized) and axotomized spinal cord motoneurons of aged cats were determined. Compared with control motoneurons, axotomized motoneurons exhibited increases in input resistance (Rin), membrane time constant (τb) and the equalizing time constant (τc). While the electrotonic length (L) remained unchanged, axotomy induced a decrease in the total cell capacitance (Ccell. The post-axotomy reduction of Ccell indicates that the motoneuron surface area was reduced and the increased membrane time constant indicates that there was an increase in membrane resistivity (Rm). The post-axotomy conservation of L accompanied by an increase in Rm suggests that aged axotomized motoneurons undergo geometrical changes. Furthermore, calculations based on cable theory suggest that the diameter of the equivalent cylinder (d) decreased following axotomy, whereas the equivalent cylinder length (l) remained unaffected. It is concluded that axotomy produces significant alterations in the soma-dendritic portion of aged spinal motoneurons, as indicated by the changes found in their passive electrophysiological properties, and that the pattern of the response that occurs in axotomized motoneurons of adult cats is also present in axotomized motoneurons of aged animals. 相似文献
32.
Francisco M. Averhoff Edward Brink Bette Pollard Karen Resha Gloria Bryan Margaret V. Vaillancourt 《The Journal of school health》1997,67(7):304-308
ABSTRACT: On March 11–12, 1996, a workshop on how to implement new adolescent immunization (AI) recommendations was held in Atlanta, Ga. Sponsored by the Centers for Disease Control and Prevention, it was a collaborative effort of the National Immunization Program, the Division of Adolescent and School Health/National Center for Chronic Disease Prevention and Health Promotion, and the Hepatitis Branch/National Center for Infectious Diseases. The workshop brought together organizations and individuals interested in adolescent health and immunizations so they could address how new Al recommendations can be implemented most effectively. This article offers an overview of their discussions and suggestions, including issues of cooperation, education, legislation, and Al program development among health provider organizations, health departments, schools, community groups and various other agencies relating to adolescent health services. 相似文献
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34.
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
35.
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
36.
37.
Iñaki Cercadillo-Ibarguren Leonardo Berini-Aytés Vicente Marco-Molina Cosme Gay-Escoda 《Journal of oral pathology & medicine》2006,35(8):513-516
The case describes a 38-year-old woman presenting a multilocular radiolucency affecting the entire right half of the lower jaw, with an unerupted third molar displaced to the region of the coronoid process. The histological study showed the presence of fibroblasts, focally with pleomorphic nuclei, dense collagen and an odontogenic epithelium with dystrophic calcifications. A cyst with an important inflammatory infiltrate was, moreover, observed. 相似文献
38.
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
39.
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
40.
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