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41.
Preventive care: do we practice what we preach?   总被引:9,自引:5,他引:4       下载免费PDF全文
We used insurance claims from enrollees in the Rand Health Insurance Experiment to determine the amount of selected components of preventive care received by a representative sample of the non-aged population in the United States and to determine whether insurance coverage was an important determinant of that amount. Only 45 percent of infants received timely immunization for DPT and polio; 93 per cent received some well child care by 18 months of age. In the three-year experimental period, only 4 per cent of adults had a tetanus shot, 66 per cent of women aged 17-44 and 57 per cent aged 45-65 received a Pap smear, and 2 per cent of women aged 45-65 had a mammogram. Cost sharing was associated with even less preventive care: 60 per cent of children on the free plan and 49 per cent on cost sharing plans received preventive care of any type. For adults, women on the free plan received more preventive care of several kinds, and those aged 45-65 received more Pap smears than those on cost-sharing plans. Even with free care, most enrollees did not receive adequate preventive care. Thus, free care alone, while significant, is not a sufficient incentive to providing recommended levels of preventive care. The average per person insurance charge for increasing the amount of preventive care to a level consistent with that recommended would be $22 for a complete set of immunizations by age 18 months, $9 for a Pap smear every three years, and $97 for a Pap test and mammogram every three years.  相似文献   
42.
The use of mechanical ventilation in the Emergency Department requires adequate resources in order to maintain patient safety and avoid potential risks. Moreover, developments in technology require increased knowledge of mechanical ventilation techniques to address the complexity of decision-making involved. Organisational issues and system factors have the potential to negatively impact on the ability of the emergency service to provide optimum care to patients receiving mechanical ventilation. These issues include staffing and skill-mix, demand on emergency services, role-delineation, scope of practice, and current mechanisms for monitoring of quality and safety. Furthermore, in response to advances in ventilator technology, current education programs for both nursing and medical staff require review to ensure that they provide comprehensive information about the types of ventilation techniques now available and the relative risks and benefits associated with their application.This article is the second in a two-part series and explores the educational and organisational factors that impact upon safety and quality of care delivered to patients receiving mechanical ventilation in the emergency department. Recommendations for future policy development, curriculum review and reporting mechanisms to support further research in the application of mechanical ventilation in the emergency department are made.  相似文献   
43.
Thirty C57BI mice were randomized into two groups. Group 1 served as controls while Group 2 was given 10% V/V ethanol with the drinking water. Whole blood- associated acetaldehyde (WBAA) was measured on capillary blood samples using a fluorigenic high performance chromatographic assay. WBAA peaked at Day 2. A stable mean plateau of 263 +/- 71 SD with a range of 160-400 nmoles/g hemoglobin WBAA was found in the group consuming ethanol compared with 122 +/- 17 SD and a range of 88-150 nmoles/g hemoglobin for controls (p less than 0.001). When ethanol was discontinued, levels of WBAA declined and became similar to those of controls by 9 days following cessation of ethanol. The quantitative difference between ethanol-consuming and control animals and also the rapid rise of whole blood-associated acetaldehyde and the relatively slow decline following cessation of ethanol intake indicate that such a test might be a useful monitor of drinking behavior.  相似文献   
44.
Mental health centers and other government sponsored service organizations need highly effective management techniques. In this era of tightening budgets, the Japanese Management System may be a way of increasing both excellence and employee satisfaction. Managers who choose to explore this system may need a concise, written model as a guide to the ingenious, extensive, and paradoxical Japanese Management System. The System centers around quality control circles—autonomous problem-solving groups that strive for excellence. Composed of hierarchically interlocking groups, it uses a wide selection of group cohesion techniques to inspire esprit de corps, and an interlocking set of rewards governs behavior at every level. Decision making is collective (although supervisors retain veto power), and execution of ideas, once agreed upon, is quick and consistent. The System operates holistically, enthusiastically, with a high degree of excellence and mutual concern.  相似文献   
45.
Laser energy at a wavelength of 480 nm was applied in 1-microseconds pulses of 3 to 10 mJ to two models of vasospasm. Rabbit common carotid arteries (CCA's) were constricted chronically by the application of human blood within a silicone sheath. Peak vasospasm developed 24 to 48 hours later, and persisted for up to 6 days. Endovascular laser treatment was delivered to 40 CCA's via a 200-microns diameter silica quartz fiber introduced through the femoral artery. The CCA caliber increased from 60% of the pre-vasospasm control diameter to a minimum post-laser diameter of 83% of control. No instances of laser-induced perforation or of arterial thrombosis were observed for up to 60 days after treatment. Prophylactic laser application to nine normal vessels was able to attenuate the development of vasospasm if blood was applied immediately thereafter (88% vs. 59% of control diameter, p less than 0.02), but not if blood was applied 7 days later. Studies in 16 normal CCA's established that there was a considerable margin between the laser energy required to induce dilatation and that which caused perforation, providing that the fiber remained relatively central within the artery. Morphological examination demonstrated focal loss of endothelial cells immediately after laser application, followed approximately 7 days later by the development of areas of intimal hyperplasia. Only minimal changes were observed in the medial or adventitial layers. In a second study, the basilar artery of seven dogs was constricted chronically by two intracisternal injections of autologous blood 3 days apart. Five dogs received endovascular laser treatment 7 or 10 days after the first injection, when basilar artery diameter was reduced to a mean of 61% and 77% of control, respectively. Immediately following treatment, basilar artery diameter increased to 104% and 102% of resting diameter, respectively. Both untreated and laser-treated arteries were smaller than the control diameter at 30 days (80% and 82%, respectively), but in each group the vasodilatory response to hypercapnia was preserved. These findings indicate that 1-microsecond laser pulses are well tolerated by systemic and cerebral arteries in two different animal models, and suggest that the 480-nm pulsed-dye laser may have an application for the treatment or prophylaxis of cerebral vasospasm.  相似文献   
46.
47.
The authors measure the efficacy of three methods for predicting the time to infection for susceptible individuals in a population undergoing an HIV epidemic. The methods differ in whether they require detailed information of the contact network and whether they require knowledge of the initial source of infection. Efficacy is evaluated using simulations for 20 different contact patterns. Only the risk score that uses both kinds of information accounts for more than 15 per cent of individual variability. The efficacy of this score ranges from 10 per cent in very unstructured populations to 60 per cent for spatially localized contact networks. This improved performance may be explained by the larger fraction of the total variability not due to the disease dynamics. When all variables are dichotomized, the two poorer methods produce odds ratios between 1.4 and 2.3. The odds ratio for the risk score with full information ranges from 2.5 to 17. Risk assessment protocols and intervention programmes are encouraged to assess contact patterns and detect sources of infection.  相似文献   
48.
Specific proteolytic destruction of the human chemotaxin, C5a, is a property of group A and B streptococcal pathogens. Here we show that virulent group G streptococci from human sources also express C5a peptidase activity. The enzyme responsible for this activity is approximately the same size as and is antigenically similar to that produced by group A streptococci. On the basis of Southern hybridization analysis with an internal fragment of the group A C5a peptidase gene (scpA) as a probe, a copy of this gene was found in the genome of all group G human isolates tested. Comparison of partial restriction maps of scpA and scpG revealed significant similarity between the two genes. Group G strains isolated from dogs and cows were found to lack C5a peptidase activity and did not hybridize to the scpA-specific probe. The association of this activity with three streptococcal species suggests that elimination of phagocyte chemotactic attractants is a more universal virulence mechanism than originally anticipated.  相似文献   
49.
Analysis was made of the results of the treatment of 18 children afflicted with lymphoblastic lymphosarcoma, with estimation of predictors influencing the patients' survival (from 1980 to 1986). The most important predictors influencing the 2-year relapse-free survival were found to be the stage, localization of the process, the presence of the symptoms of intoxication and biological activity. The data obtained were used later in the treatment of 160 children during 1986 to 1989. The results of the 2-year survival of this patients' group appreciably differ from those derived before.  相似文献   
50.
Several clinical and pathologic factors appear to affect melanoma recurrence and survival. While much attention has been directed at identifying prognostic factors, few researchers have developed predictive models for survival and recurrence. Two major clinical questions are of interest in the management of melanoma: 1) what is the patient's chance of surviving for a given period, e.g., 5 or 10 years, after diagnosis of melanoma; and 2) after a patient has been disease free for a period of time, e.g., 5 years, what is his or her chance of melanoma recurrence or death in the following interval, e.g., 5 years or 10 years. In this paper, a generalized multivariate prognostic model to address both of these clinical questions is presented.Tables of the estimated probabilities of melanoma recurrence and death for prognostic subgroups are shown to facilitate prediction of an individual patient's outcome. The model was based on a database of 4,568 patients with localized melanoma, one of the largest melanoma databases in the world with detailed clinical and pathologic information, and long-term follow-up. Tumor thickness at diagnosis was the single most important prognostic factor for all outcomes. Tumor ulceration, Clark's level, lesion location, and sex had an impact on overall survival from diagnosis for some of the subgroups defined by tumor thickness. Tumor thickness at diagnosis was strongly indicative of melanoma recurrence and death even after a disease free interval of 2, 5, or 10 years. Lesion location and ulceration were of prognostic importance after disease free intervals up to 5 years, but their impact on melanoma recurrence and death diminished after longer disease free intervals.Prediction models for melanoma outcome at diagnosis and after a disease free period can provide useful information to clinicians in the management of melanoma patients. Utilization of the model will be valuable in identifying patients at high risk for melanoma recurrence and death.
Resumen Diversos factores clínicos y patológicos parecen afectar las tasas de recurrencia y mortalidad del melanoma. En tanto que se ha dispensado bastante atención en cuanto a identificar factores de pronóstico, pocos investigadores han desarrollado modelos de predicción de sobrevida y de recurrencia. Dos interrogantes principales son de interés en cuanto al manejo del melanoma: 1) cual es la probabilidad del paciente de sobrevivir un determinado período, por ejemplo 5 o 10 años, después del diagnóstico de melanoma; y 2) después de que el paciente se ha mantenido libre de enfermedad por un período de tiempo, por ejemplo 5 años, cual es su probabilidad de recurrencia del melanoma o de muerte en el siguiente período de tiempo, por ejemplo 5 o 10 años. En este artículo se presenta un modelo generalizado y multivariable de pronóstico para enfrentar estos interrogantes clínicos.Se presentan tablas para estimar las probabilidades de recurrencia y de muerte en divesos subgrupos de pronóstico que facilitan la predicción del destino final de un individuo. El modelo se fundamentó en una base de datos de 4568 pacientes con melanomas localizado, una de las más grandes bases de datos de melanoma existentes en el mundo, con detallada información clínica y patológica y con seguimiento a largo plazo. El espesor del tumor en el momento del diagnóstico apareció como el factor individual de pronóstico de mayor importancia. La ulceración del tumor, el nivel de Clark, la ubicación de la lesión y el sexo exhibieron importancia en cuanto a la sobrevida para algunos de los subgrupos definidos según el espesor del tumor. El espesor del tumor en el momento del diagnóstico fue un factor fuertemente indicativo de recurrencia y de muerte, aún después de un intervalo libre de enfermedad de 2, 5 o 10 años. La ubicación de la lesión y la ulceración aparecieron como de importancia en cuanto el pronóstico después de intervalos libres de enfermedad hasta de 5 años, pero tal importancia disminuyó después de intervalos libres de enfermedad de mayor duración.Los modelos de predicción del resultado final en el melanoma aplicados en el momento del diagnóstico y después de un período libre de enfermedad pueden proveer información útil para el manejo clínico de pacientes con melanomas. La utilización del modelo es de valor en la identificación de pacientes con mayor riesgo de recurrencia y muerte por melanoma.

Résumé Plusieurs facteurs cliniques et anatomopathologiques semblent déterminer la récidive et la survie des mélanomes. De nombreux auteurs se sont intéressés à l'identidification des facteurs de pronostic, mais peu d'équipes ont essayé d'élaborer un modèle permettant de prédire survie et récidive. Deux problèmes restent à résoudre dans le traitement des mélanomes: 1) quelles sont les chances de survie après le diagnostic de mélanome pour un patient donné, pendant une période donnée, par exemple 5 à 10 ans et 2) quels sont les risques de récidive ou de décès dans les 5 à 10 ans qui suivent une période donnée (par exemple 5 ans) où un patient semblait en rémission. Dans cet article, nous avons créé un modèle d'évaluation pronostique multifactorielle pour tenter de répondre à ces 2 questions.Des tables montrant les probabilités de récidive et de décès par mélanome, calculées à partir de sous groupes différents, peuvent aider à déterminer le pronostic. Ce modèle repose sur une banque de données de 4568 patients atteints de mélanome non disséminé. Il s'agit d'une des plus grandes banques de données au monde contenant des informations cliniques, anatomopathologiques et sur l'évolution à long terme. L'épaisseur de la tumeur au moment du diagnostic était le facteur pronostic le plus important pour déterminer l'évolution. Le caractère ulcéré, le stade de Clark, la localisation de la lésion et le sexe avaient tous une importance pronostique, influant sur la survie globale liée à l'épaisseur de la tumeur. L'importance de l'épaisseur de la tumeur au moment du diagnostic était un facteur de récidive et mortalité même après un intervalle long de 2, 5 ou 10 ans. Le site de la tumeur et son caractère ulcéré étaient également des facteurs associés à un risque de récidive tumorale ou de décès après une rémission de 5 ans. L'influence de ces facteurs diminuait en cas de rémission plus prolongée.Les modèles permettant d'évaluer l'évolution du mélanome malin au moment du diagnostic et apreès un intervalle de rémission sont utiles au cours du traitement du mélanome. Ils doivent permettre d'identifier les patients à risque de récidive et de décès.
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