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81.
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
82.
Angela Ohlemacher Rainer Schenk Hans Peter Weitzel Nikolai Tyutyulkov Maria Tasseva Klaus Müllen 《Macromolecular chemistry and physics.》1992,193(1):81-93
The energy gaps of poly(p-arylenevinylene)s with phenylene, naphthylene and anthrylene subunits are determined by extrapolating the UV/VIS spectroscopic data of the oligomers. The band structure of the three polymers was theoretically investigated. The topology-, geometry- and correlation-factors were determined upon which the energy spectra of this class of one-dimensional π-electron systems depend. 相似文献
83.
Summary Estrogen has an important role in stimulating the growth of breast carcinomas. Inhibition of estrogen production is therefore a logical treatment strategy. A number of selective inhibitors have been developed against aromatase, a cytochrome P-450 enzyme which catalyzes the rate limiting step in the biosynthesis of estrogens. The mechanisms of the aromatase reaction, current knowledge of the enzyme, and regulation of its expression are discussed as the basis for inhibitor development. Two classes of aromatase inhibitors, steroidal and non-steroidal compounds, are now coming into use. Among the steroid substrate analogues, 4-hydroxyandrostenedione (4-OHA) has been shown to be effective in breast cancer patients with advanced disease and was recently approved for treatment in the United Kingdom. Several different classes of compounds which act as aromatase inhibitors are currently in clinical trials and should provide breast cancer patients with a number of treatment options. Among these are highly potent and selective non-steroidal inhibitors which have recently been found to suppress plasma and urinary estrogens over 95% in breast cancer patients. The potency of these newer aromatase inhibitors provides the opportunity to determine whether complete suppression of estrogen production and action will result in enhanced tumor regression. 相似文献
84.
Ian A Simpson Anthony Carruthers Susan J Vannucci 《Journal of cerebral blood flow and metabolism》2007,27(11):1766-1791
Glucose is the obligate energetic fuel for the mammalian brain, and most studies of cerebral energy metabolism assume that the majority of cerebral glucose utilization fuels neuronal activity via oxidative metabolism, both in the basal and activated state. Glucose transporter (GLUT) proteins deliver glucose from the circulation to the brain: GLUT1 in the microvascular endothelial cells of the blood-brain barrier (BBB) and glia; GLUT3 in neurons. Lactate, the glycolytic product of glucose metabolism, is transported into and out of neural cells by the monocarboxylate transporters (MCT): MCT1 in the BBB and astrocytes and MCT2 in neurons. The proposal of the astrocyte-neuron lactate shuttle hypothesis suggested that astrocytes play the primary role in cerebral glucose utilization and generate lactate for neuronal energetics, especially during activation. Since the identification of the GLUTs and MCTs in brain, much has been learned about their transport properties, that is capacity and affinity for substrate, which must be considered in any model of cerebral glucose uptake and utilization. Using concentrations and kinetic parameters of GLUT1 and -3 in BBB endothelial cells, astrocytes, and neurons, along with the corresponding kinetic properties of the MCTs, we have successfully modeled brain glucose and lactate levels as well as lactate transients in response to neuronal stimulation. Simulations based on these parameters suggest that glucose readily diffuses through the basal lamina and interstitium to neurons, which are primarily responsible for glucose uptake, metabolism, and the generation of the lactate transients observed on neuronal activation. 相似文献
85.
Bob Simpson 《The British journal of general practice》2003,53(493):660-661
86.
Fumiaki Ikeno Tomoaki Hinohara Gregory C Robertson Mehrdad Rezaee Paul G Yock Bernhard Reimers Antonio Colombo Eberhard Grube John B Simpson 《Catheterization and cardiovascular interventions》2004,61(1):35-43
The use of directional coronary atherectomy (DCA) in current practice has been limited. The SilverHawk System is a newly developed plaque excision device that aims to overcome the drawbacks of prior DCA platforms. The device was evaluated in a porcine coronary model and in a series of patients. Procedural variables along with outcomes were reviewed. Quantitative angiography (QCA) was performed and excised tissue fragments were weighed and examined histologically. In porcine cases, pretreatment MLD increased from 0.51 +/- 0.26 to 2.36 +/- 0.59 mm postdebulking and 19.9 +/- 7.6 mg of tissue was retrieved. In human cases, pretreatment MLD increased from 0.8 +/- 0.4 to 2.2 +/- 0.5 mm postdebulking and 15.2 +/- 7.8 mg of tissue was retrieved without complications. These data show that the SilverHawk System may offer significant utility in treating a wide variety of complex coronary lesions. 相似文献
87.
Trauma is a major cause of mortality and morbidity in the United States, with blunt traumatic injuries of the thoracic aorta continuing to occur despite the increased use of seatbelts and airbags. Emerging from crash analysis are effective interventions and provides increased awareness of the occult nature of these types of injuries. This article describes those interventions that healthcare providers must embed throughout the continuum of care for patients experiencing thoracic aortic injuries. Outcomes will be dependent upon the healthcare provider's knowledge of the physics of the event and the urgency of the diagnosis, as well as the ability to assess and manage all the variables involved. Current procedural issues are delineated and case studies are used to illustrate the processes of care needed by these patients. 相似文献
88.
A survey was conducted to ascertain the risk of tuberculosis (TB) among migrant farm workers on the Delmarva peninsula. Relevant histories were obtained from 842 migrants; a total of 709 skin tests were completed, and 239 sputum specimens were examined for acid-fast bacilli (AFB) and culture. No cases of infectious tuberculosis were ascertained by history or AFB examination. One sputum culture was positive for M. tuberculosis and 13 were positive for various species of nontuberculous mycobacteria. Thirty-seven per cent of migrants tested had significant skin test reactions of 10 mm or more. Reaction rates for men were 41 per cent and for women 25 per cent. Age specific rates ranged from 14 per cent in children aged 5-14 to 54 per cent for ages 45-54. Rates for the principal national/ethnic groups were Haitians 55 per cent, Mexicans 36 per cent, US Blacks 29 per cent and US-born Latinos 20 per cent. Based on these results and other information currently available, it is recommended that current Centers for Disease Control (CDC) recommendations for TB prophylaxis continue to be applied for migrant workers, but that mass screening by skin testing in camp populations not be emphasized. Other recommendations focus on: case finding of active disease, improving continuity and follow-up, increasing coordination among involved agencies, and actively supporting improved economic and living conditions for migrant farm workers. 相似文献
89.
I Simpson 《Canadian Medical Association journal》1991,144(7):908-909
90.
Interactions Between Cytomegalovirus, Human Herpesvirus-6, and the Recurrence of Hepatitis C After Liver Transplantation 总被引:1,自引:0,他引:1
Atul Humar Deepali Kumar Janet Raboud Angela M. Caliendo George Moussa Gary Levy Tony Mazzulli 《American journal of transplantation》2002,2(5):461-466
Recurrence of hepatitis C (HCV) following liver transplantation is common. Herpesvirus reactivation following transplant may have an immunomodulatory effect resulting in increased HCV replication. We studied whether cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6) may be associated with HCV recurrence and viral load after transplant. We prospectively followed 66 HCV liver-transplant recipients with serial viral load testing for CMV and HHV-6. Infection and viral load were correlated with the development of biopsy-proven HCV recurrence and HCV viral loads. Histologic recurrence of HCV occurred in 41/66 (62.1%) patients. In the primary analysis, CMV infection and disease, and HHV-6 infection were not associated with HCV recurrence. Peak CMV and HHV-6 viral loads were not significantly different in patients with and without recurrence. No correlation was observed between HCV viral loads at 1 and 3 months post-transplant and peak HHV-6 or CMV viral loads. In a subgroup analysis, HHV-6 infection was associated with the development of more severe recurrence (hepatitis and/or fibrosis score > or = 2) (p = 0.01). Also, fibrosis scores at last follow up were higher in patients with CMV disease (1.67 vs. 0.56; p = 0.016) and in patients with HHV-6 infection (1.18 vs. 0.55; p = 0.031). In conclusion, HHV-6 and CMV infection and viral load were not associated with increased overall rates of HCV recurrence or HCV viral load after liver transplantation but may be associated with more severe forms of recurrence. 相似文献