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A T Edmunds  S Godfrey 《Thorax》1981,36(7):534-540
Heart rate, blood pressure, pulsus paradoxus, and cardiac output measured by means of transthoracic electrical impedance cardiography have been recorded in 29 children mean age 10 years +/- 2 SD during status asthmaticus. Changes were recorded over the first two hours of treatment during which all patients received oxygen, intravenous fluid, and hydrocortisone, and were randomly assigned to receive aminophylline, salbutamol, or both. Admission values showed significant correlation of pulsus paradoxus with PaCO2 (r = 0.66). Pulsus paradoxus was greater than 20 mmHg for all patients with PaCO2 above 5.5 kPa. Mean stroke volume and cardiac output were 89% and 131% of the resting convalescent values in the same children. Stroke volume cardiac output and heart rate did not correlate with peak expiratory flow rate or blood gas measurements. Aminophylline and salbutamol together were associated with significantly greater increase in PEF than aminophylline alone (P less than 0.05). Nebulised salbutamol was just as effective as intravenous salbutamol. Heart rate and systolic blood pressure declined significantly after nebulised salbutamol and aminophylline, but not after intravenous salbutamol and aminophylline. Stroke volume and cardiac output did not change significantly in any treatment group.  相似文献   
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BACKGROUND: To develop a multiprofessional consensus about the relative contributions of the components of children's health and well-being and to develop a questionnaire that can be used to assess these in London's children. METHODS: Semi-structured interviews with health, education and social services professionals were used to identify areas to include in the questionnaire. These ideas were used as the basis for a wider Delphi consultation, with 79 experts in the area of child health. Round 1 of the Delphi asked panelists to rate 54 items as to whether they should be included in the questionnaire or not. Responses were divided into four categories: item to be included measurement method agreed, item to be included measurement method not agreed, no consensus, or excluded. In round 2, consensus was sought for the categories where there was none following round 1. RESULTS: Themes identified by the interviews were: economic factors, ethnicity, environment, nutrition, hygiene and physical activity, growth, suffers from chronic/serious illness, development, disability and learning, accidents and hospital attendances, self-regulation, psychological well-being, significant life events. After Delphi round 1, items included, where quality measurement method was agreed, were: deprivation index (from postcode), child's ethnicity, temporary accommodation, care status, registered with general practitioner, dental visits, height, weight, special educational needs status, baseline educational assessment result, immunization status, visual and hearing function. Following round 2, items relating to chronic illness, mental health, physical functioning, general health, self-esteem, family cohesion and accident status were agreed for inclusion with a measurement method also agreed. The questionnaire was acceptable to parents. CONCLUSION: The validity, reliability and feasibility of this questionnaire must now be examined. This data set, if collected across London, would substantially increase the public health data available and allow trends in health to be monitored.  相似文献   
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High titres of pertussis toxin (PT) antibody have been shown to be predictive of recent infection with Bordetella pertussis. The seroprevalence of standardized anti-PT antibody was determined in six Western European countries between 1994 and 1998 and related to historical surveillance and vaccine programme data. Standardized anti-PT titres were calculated for a series of whole-cell and acellular pertussis vaccine trials. For the serological surveys, high-titre sera (> 125 units/ml) were distributed throughout all age groups in both high- (> 90%) and low-coverage (< 90%) countries. High-titre sera were more likely in infants in countries using high-titre-producing vaccines in their primary programme (Italy, 11.5%; Western Germany, 13.3%; France, 4.3%; Eastern Germany, 4.0%) compared to other countries (The Netherlands, 0.5%; Finland, 0%). Recent infection was significantly more likely in adolescents (10-19 years old) and adults in high-coverage countries (Finland, The Netherlands, France, East Germany), whereas infection was more likely in children (3-9 years old) than adolescents in low-coverage (< 90%; Italy, West Germany, United Kingdom) countries. The impact and role of programmatic changes introduced after these surveys aimed at protecting infants from severe disease by accelerating the primary schedule or vaccinating older children and adolescents with booster doses can be evaluated with this approach.  相似文献   
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The expected increase in the number of practicing physicians does not necessarily mean that new health practitioners will not have a role. It may mean that adaptation and renegotiation of the roles are required. Filling unmet national needs, including providing primary care in undeserved areas and delivering preventive care can be achieved without unreasonable feelings of competition if nurse practitioners remain flexible and respond to new opportunities.  相似文献   
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Contact between blood and synthetic surfaces of an extracorporeal circuit results in extensive alterations in platelet function. These platelet abnormalities have been reproduced in vitro by recirculating heparinized (5 units/ml) human blood at 37 degrees C in a silicone rubber circuit (0.1 m2) containing a spiral coil membrane oxygenator (0.9 m2). During control recirculation trials, platelet counts fell to 29% +/- 8% (mean +/- standard error of the mean) of initial levels within 30 minutes, and sensitivity to the soluble agonists, adenosine diphosphate and epinephrine, disappeared. Plasma levels of the platelet-specific protein platelet factor 4 rose to 2,600 +/- 200 ng/ml, indicating extensive platelet granule release. Similarly, plasma concentrations of thromboxane B2 rose from less than or equal to 100 pg/ml to 500 +/- 200 pg/ml at 120 minutes, and transmission electron microscopy demonstrated disruption of platelet subcellular architecture. In contrast, when ilioprost, a stable prostacyclin derivative (1 ng/ml), was added to the circuit prior to recirculation, the thrombocyte count remained at 85% +/- 4% of initial values. Platelets incubated or recirculated for 2 hours in the presence of iloprost responded normally to both adenosine diphosphate and epinephrine after separation from the drug by gel-filtration. Furthermore, plasma concentrations of platelet factor 4 remained below 300 ng/ml, plasma levels of thromboxane B2 failed to reach detectable levels, and platelet ultrastructure remained intact. Thus, iloprost effectively preserves the circulating platelet count, prevents platelet granule release, and preserves platelet functional and morphological integrity during simulated extracorporeal circulation.  相似文献   
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