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41.
The quality of medical education during internship is a cause for concern. This paper describes a structured educational programme for interns that was based around learning modules, clinical attachments and bedside teaching. The programme was incorporated into the term rotation of interns within an Area Health Service, and evaluated. Learning modules were timetabled by a Programme Coordinator and interns were reminded to attend. Clinical attachments were organized by the interns from a list of willing supervisors. Attendance at timetabled learning modules averaged 67%, which was greater than the 27% attendance at clinical attachments. Both sessions received high ratings for quality and clinical relevance. This structured education programme was based upon adult learning methods and was both feasible and well received by interns. Intern training programmes need to be programmed into the working week to ensure attendance, and modified following evaluation by interns. Such programmes should be considered by all hospitals to which interns are allocated.  相似文献   
42.
On the dangers of monitoring. Or, Primum non nocere revisited   总被引:1,自引:0,他引:1  
D. A. Saunders 《Anaesthesia》1997,52(5):399-400
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44.
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.
  相似文献   
45.
This paper reviews the basic thermoregulatory physiology of healthy people in relation to hazards from external heat stress and internal heat loads generated by physical exercise or radiofrequency (RF) radiation. In addition, members of the population are identified who may be particularly vulnerable to the effects of heat stress. These data are examined in relation to current international guidance on occupational and public exposure to RF radiation. When body temperature rises, heat balance of the body is normally restored by increased blood flow to the skin and by sweating. These responses increase the work of the heart and cause loss of salt and water from the body. They impair working efficiency and can overload the heart and cause haemoconcentration, which can lead to coronary and cerebral thrombosis, particularly in elderly people with atheromatous arteries. These adverse effects of thermoregulatory adjustments occur with even mild heat loads and account for the great majority of heat-related illness and death. They are, therefore, particularly relevant to determination of safe population exposures to additional sources of heat stress. It is concluded that exposure to RF levels currently recommended as safe for the general population, equivalent to heat loads of about one tenth basal metabolic rate, could continue to be regarded as trivial in this context, but that prolonged exposures of the general population to RF levels higher than that could not be regarded as safe in all circumstances.  相似文献   
46.
1. Repair and recovery following spinal cord injury (complete spinal cord crush) has been studied in vitro in neonatal opossum (Monodelphis domestica), fetal rat and in vivo in neonatal opossum. 2. Crush injury of the cultured spinal cord of isolated entire central nervous system (CNS) of neonatal opossum (P4–10) or fetal rats (E15–E16) was followed by profuse growth of fibres and recovery of conduction of impulses through the crush. Previous studies of injured immature mammalian spinal cord have described fibre growth occurring only around the lesion, unless implanted with fetal CNS. 3. The period during which successful growth occurred in response to a crush is developmentally regulated. No such growth was obtained after P12 in spinal cords crushed in vitro at the level of C7–8. 4. In vivo, in the neonatal (P4–8) marsupial opossum, growth of fibres through, and restoration of, impulse conduction across the crush was apparent 1–2 weeks after injury. With longer periods of time after crushing a considerable degree of normal locomotor function developed. 5. By the time the operated animals reached adulthood, the morphological structure of the spinal cord, both in the region of the crush and on either side of the site of the lesion, appeared grossly normal. 6. The results are discussed in relation to the eventual longterm possibility of devising effective treatments for patients with spinal cord injuries.  相似文献   
47.
Recently, the authors managed three patients with AIDS and venous thromboembolism. All three were active, ambulatory, and without known risk factors for pulmonary embolism or deep venous thrombosis. One patient had a low titer for IgG anticardiolipin antibody (1:13). Two had low normal values for free protein S, and the third patient had a very low value (5%). Clinicians caring for AIDS patients should be alert to the possibility that venous thromboembolism may complicate HIV infection.  相似文献   
48.
All physicians who had billed Pennsylvania Blue Shield for at least three intravenous contrast studies during 1989 were surveyed on their use of nonionic versus ionic contrast. This surveyed group represents a diversity of hospital sizes, practice types, and group sizes. Of the 383 physician groups surveyed, responses were obtained from 285. The majority of the responding groups were radiologists (94.0%). Nonionic contrast is utilized in 41.3% of all intravenous studies. Radiologists use nonionic contrast in a much greater proportion than nonradiologists (P < 0.0001), with 17.6% of radiologists utilizing nonionic contrast in all of their patients. Conversely, 75% of nonradiologists utilize ionic contrast in all of their patients. For all physician groups surveyed, 40.3% utilize nonionic for at least 50%, while 27.6% use nonionics for more than 75% of their patients. The routine use of steroid premedication prior to the injection of ionic contrast is not a common practice. The increased utilization of nonionic contrast found in this survey may reflect the cross-section of physicians and practice types surveyed or may represent changing practice patterns among physicians utilizing contrast material.  相似文献   
49.
Compared the performance of autistic and mentally retarded subjects, all of whom had passed a standard first-order test of false belief, on a new second-order belief task 12 autistic and 12 mentally retarded subjects, matched on verbal mental age (assessed by PPVT and a sentence comprehension subtest of the CELF) and full-scale IQ were given two trials of a second-order reasoning task which was significantly shorter and less complex than the standard task used in all previous research. The majority of subjects in both groups passed the new task, and were able to give appropriate justifications to their responses. No group differences were found in performance on the control or test questions. Findings are interpreted as evidence for the role of information processing factors rather than conceptual factors in performance on higher order theory of mind tasks.This study was supported by a grant from the National Institute of Deafness and Other Communication Disorders (1RO1 DC 01234). We thank Jason Barker for his extensive help with this study. We are also very grateful to the schools where the study was conducted including the League School, and the public school systems in the following towns in Massachusetts: Hanover, Hanson, Hingham, Milton, Plymouth, and Rockland. We offer special thanks to Alan Dewey, Mary Dollar, Sandy D'Giacomo, Herman Fishbein, William Griffin, Nancy Kearns, Judy Monahan, Debbie Newhall, Cay Riley, Robert Sherman, and Kathy Staska for their continued support of our research.  相似文献   
50.
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