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61.
Joyce Toral William Hu Donald Critchett Andrew J. Solomon James E. Barrett Patricia T. Sokol M. Reza Ziai 《The Journal of pharmacy and pharmacology》1995,47(7):618-622
The 5-HT3-receptor antagonist, ondansetron, has been shown to have positive effects in selected in-vivo models of memory impairment and anxiety. The exact mechanisms underlying such bioactivities are unknown. In the present work, an 86Rb efflux bioassay was used to show that ondansetron has a unique ability to block voltage-gated potassium channels in TE671 human neuroblastoma cells. This intrinsic potassium-channel-blocking (KCB) property is relatively weak (IC50 20 (M), but is not shared by other 5-HT3-receptor ligands including zatosetron, MDL 72222, LY 278, 584, zacopride, 1-phenylbiguanide, and ICS 205–930 (tropisetron). Pre-incubation of the target neuroblastoma cells with several 5-HT-receptor ligands including 5-hydroxytryptamine, 8-OH-DPAT, ketanserin, 2-methyl-5-HT, as well as a number of potent 5-HT3 agonists and antagonists and two selective neurotoxins, failed to abolish the KCB action of ondansetron. A preliminary structure-activity relationship analysis indicates that the KCB activity of ondansetron is almost entirely attributable to its structural nucleus, 2,3-dihyro-9-methyl-4(lH)-carbazolone. It is hypothesized that the KCB action of ondansetron is mediated through receptors other than 5-HT3 receptors. The KCB activity of ondansetron may be a significant factor in the in-vivo cognition-enhancing activities of this compound, conceivably due to depolarization of the hippocampal synaptic membranes and a consequent augmentation of neurotransmission. 相似文献
62.
Professor D. A. Simpson P. C. Blumbergs A. J. McLean G. Scott 《World journal of surgery》1992,16(3):403-409
In the 6-year period from 1983 to 1988, 12 infants (<24 months of age) and 103 children (2 to 14 years of age) were killed in road crashes in South Australia. This represents an annual incidence of 6.4 deaths per 100,000 children at risk. At least 4 other children were killed in off-road vehicle-related accidents. Of these deaths, approximately half were car passengers, one third pedestrians, and one sixth pedal cyclists. Most of these infants and children died at the accident site or soon after, but 26 of them survived long enough to be admitted to hospitals with neurosurgical units and an audit of these patients suggests that there were at least 3 preventable deaths. However, autopsies of 78 patients show that the great majority of these deaths resulted from devastating brain and/or trunk visceral injuries. Better emergency care and the use of neurosurgical retrieval teams may save some lives. But more lives might be saved by the use of appropriate restraints for infants and children in cars, by reducing the exposure of child pedestrians and cyclists to road traffic, and by mandatory use of helmets by child cyclists. Off-road vehicular accidents are not as a rule included in road crash statistics; the practice of giving small motorcycles to young children has created a new category of vehicular accidents sometimes causing severe head injury.
Resumen En el período de seis anños 1983–1988, murieron 12 infantes (edades menores de 24 meses) y 103 niños (edades 2–14 años) en accidentes viales en el Sur de Australia, lo cual representa una incidencia anual de 6.4 muertes por 100,000 miños en riesgo. Por lo menos cuatro niños más murieron en accidentes fuera de carreteras pero relacionados con automotores. De tales muertes, approximadamente la mitad correspondió a pasajeros en carros, una tercera parte a peatones y una sexta parte a ciclistas. La mayoría murió en el lugar del accidente o poco tiempo después, pero 26 sobrevivieron un tiempo sufiente para ser hospitalizados en instituciones con unidades neurológicas; una auditoría de tales casos sugiere que por lo menos hubo tres muertes prevenibles. Sin embargo, la autopsia de 78 casos demostró que la mayoría de estas muertes se debió a lesiones devastadores del cerebro y/o las vísceras corporales. Mejores servicios de urgencia y la utilización de equipos de resucitación neuroquirúrgica pueden salvar algunas vidas, pero más vidas pueden ser salvadas mediante el uso de sistemas adecuados de seguridad para infantes y para niños instalados en los carros, reduciendo la exposición de peatones y ciclistas infantiles al tráfico víal y mediante el uso obligatorio de cascos por los ciclistas infantiles. Los accidentes que ocurren por fuera de las carreteras generalmente no son incluídos en las estadísticas de siniestros víales; la costumbre de obsequiar pequeñas motocicletas a niños pequeños ha creado una nueva categoría de accidentes vehículares que en ocasiones causan grave trauma craneano.
Résumé Pendant la période de six ans allant de 1983 à 1988, 12 enfants âgés de moins de 24 mois et 103 enfants âgés de 2 à 14 ans ont été tués dans un accident de la route en Australie du Sud. Ceci représente une incidence annuelle de 6.4 morts par 100,000 enfants à risque. Au moins quatre autres enfants ont été dans un accident dû à un véhicule motorisé mais hors de la route. Parmi ces morts, la moitié, environ, était des passagers de la voiture, un tiers, des piétons, et un sixième, des cyclistes. La plupart sont morts sur le lieu de l'accident, mais 26 ont survécu suffisamment pour être transportés dans un Hôpital comportant une service de neurochirurgie avant de décéder. Une évaluation de ces accidents mortels a montré qu'au moins trois décès eux étaient évitables. L'autopsie de 78 de ces enfants a démontré que la plupart des décès étaient dus soit à des lésions cérébrales, soit à des lésions viscérales ou du tronc. De meilleurs soins en urgence, et un meilleur déploiment des équipes neurochirurgicales pourraient éviter quelques morts, mais aussi, un certain nombre de morts pourraient être évitées en utilisant correctement less ceintures de sécurité adaptées aux enfants dans les voitures, en réduisant l'exposition aux accidents de ces enfants, ainsi qu'en rendant obligatoire le port de casque pour les enfants se déplacant à vélo. Les accidents qui n'ont pas lieu sur les routes ne sont pas habituelement inclus dans ces statistiques. La croissance de l'utilisation de petits véhicules motorisés par de très jeunes enfants a créé une nouvelle catégorie d'accidents pouvant parfois être responsables de traumatismes crâniens graves.相似文献
63.
Donald M. Campbell Gerald I. Forbes 《International journal of environmental health research》1994,4(2):86-92
The prevention of the spread of disease by drinking water relies on a tripartate arrangement among the supplier, the regulator and their medical advisers. This paper describes the role of Public Health Medicine in Scotland in preventing a ‘significant risk to health’ from potable water. The legislative framework is highlighted. The rationale of water monitoring is examined and the role of Consultant in Public Health Medicine. The concept of Significant Medical Risk Values is introduced and their derivation, uses, and levels presented. 相似文献
64.
Gordon Winocur Fergus I M Craik Brian Levine Ian H Robertson Malcolm A Binns Michael Alexander Sandra Black Deirdre Dawson Heather Palmer Tara McHugh Donald T Stuss 《Journal of the International Neuropsychological Society》2007,13(1):166-171
This study provides an overview of the papers emanating from the experimental trial that evaluated a new cognitive rehabilitation program in older adults who were experiencing normal cognitive decline. The main features of the design are summarized, along with evidence that the training produced long-lasting improvement in memory performance, goal management, and psychosocial status. The benefits were attributed to several factors, including the program's emphasis on techniques that promoted efficient strategic processing. Limitations of the program and directions for future research are discussed. 相似文献
65.
P. J. Donald 《European archives of oto-rhino-laryngology》2007,264(7):713-717
The purpose of this paper is to detail the contraindications for surgery, with curative intent for those patients who suffer
from a head and neck malignancy that invades the intracranial space. This is based on a 30-year experience of over 250 patients.
The most important contraindications are anatomical. Surgery is not done if the following structures are invaded: brain stem,
eloquent portions of the cerebrum, superior sagittal sinus, both internal carotid arteries, both cavernous sinuses and certain
vital bridging veins. Certain tumor factors are absolute but are occasionally relative contraindications: such as distant
metastatic disease especially if multiple and at multiple anatomic sites. Some tumors that behave in a particularly virulent
fashion that defy complete resection but are often difficult to predict preoperatively. Lack of patient medical fitness or
absence of patient commitment to the operative procedure is make-up two serious contraindications to surgery.
Presented at the 77th Annual Meeting of the German Society for Oto-Rhino-Laryngology, Head and Neck Surgery, 24–28 May 2006,
Mannheim, Germany. 相似文献
66.
Deborah K. Rasch Frederick Browder Marjory Barr Donald Greer 《Journal canadien d'anesthésie》1986,33(3):364-370
We present three patients with Treacher Collins or Pierre Robin syndromes who had historical and physical evidence of airway obstruction, difficulty feeding, and sleep disturbances. These preoperative findings correlated with difficult airway management intraoperatively. Based on this experience, we recommend that children with obstructive symptoms have laryngoscopy prior to anaesthetic induction. If the glottic opening is visualized, inhalational induction can proceed. If the glottic structures cannot be visualized, then the anaesthetist must choose between awake oral or nasal intubation, elective tracheostomy, or fiberoptic intubation. In all cases, a tracheostomy tray should be ready and a surgeon experienced in paediatric tracheostomy should be in attendance. After intubation, anaesthesia is best maintained with oxygen and a potent inhalational agent. Extubation should only be done with the patient fully awake and with emergency airway equipment immediately available. Postoperatively, these patients should be transferred to an intermediate care area or intensive care unit where they can be observed closely since delayed complications of airway obstruction are common in this group of patients. 相似文献
67.
Larry R. Faulkner M.D. Joseph D. Bloom M.D. David L. Cutler M.D. James H. Shore M.D. J. Donald Bray M.D. Joseph Murray M.S. 《Community mental health journal》1987,23(4):260-270
The authors review the relationship that has evolved over the years between the Department of Psychiatry at Oregon Health Sciences University and Oregon's community and state mental health programs. They describe the compatibility that exists between the basic requirements of academic psychiatry departments and public mental health programs and demonstrate how these organizations have been able to fulfill one another's needs in Oregon. Specific examples of successful collaborations in the areas of education, administration, research, and service are presented to illustrate how relationships that have been designed to meet specific requirements of one organization can fulfill many requirements of both. Suggestions are provided for those organizations contemplating similar collaborative endeavors. 相似文献
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