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BACKGROUND. This study was designed to determine the variability in the consultation practices of family physicians and family nurse practitioners in an urban group practice, and to examine the relation between the referring practitioner's diagnostic certainty at the time of the consultation request, the specificity of the request to the consultant, and the frequency with which the practitioner ordered consultations in that specialty. METHODS. This study examined consultations requested by six family physicians and two family nurse practitioners that were directed to nine medical and surgical specialties in connection with 35,218 family practice visits made over a 19-month period in an urban family practice. Requests for consultation were scored based on the level of certainty of the referring practitioner's diagnosis at the time of consultation and the specificity of the consultation request. RESULTS. There was nearly a fivefold variation in the overall specialty consultation rates among providers, with even greater variation in each individual specialty area studied. Referral rate correlated positively with certainty of diagnosis (r = .40). There was no consistent relation between request specificity and referral rate. CONCLUSIONS. Consultation rates vary widely, even among family physicians and nurse practitioners within the same practice. The rate at which a practitioner orders consultations in a specialty area increases in relation to the practitioner's certainty of the diagnosis at the time the consultation was requested. Diagnostic certainty is discussed as a possible indicator of a referring practitioner's knowledge in a specialty area, implying that the greater a practitioner's knowledge in a specialty area, the more he or she consults with specialists in the field. Financial incentives that attempt to decrease specialty consultation should be reexamined in light of these findings. 相似文献
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Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
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Chemical constituents of diesel exhaust particles induce IL-4 production and histamine release by human basophils 总被引:5,自引:0,他引:5
Devouassoux G Saxon A Metcalfe DD Prussin C Colomb MG Brambilla C Diaz-Sanchez D 《The Journal of allergy and clinical immunology》2002,109(5):847-853
BACKGROUND: An epidemiologic relationship between airway allergic diseases and exposure to atmospheric pollutants has been demonstrated and suggested to be one factor in the increasing prevalence of asthma. Diesel exhaust particles (DEPs) have been shown to participate in the development of allergic airway inflammation, in which the targets include macrophages, B and T cells, epithelial cells, and mast cells. In addition to the adjuvant effect of DEPs on total and allergen-specific IgE production, DEPs also act to induce chemokines and cytokines and may play a key role in primary sensitization. OBJECTIVE: DEPs have been shown to increase local IL-4-containing Kit(+) cells soon after in vivo nasal challenge. The aim of this study was to examine the effects of DEPs on human basophils, a key source of IL-4. METHODS: Peripheral blood leukocytes from allergic and control subjects were cultured in the presence of organic extracts of DEP (DEPex) with or without allergen. The cultures were analyzed for IL-4-containing cells by using multiparameter flow cytometry, IL-4 secretion with ELISA, and histamine release. RESULTS: Basophils, when exposed in vitro to DEPex, expressed IL-4 and released histamine significantly (P <.01) more than with antigen activation. DEPex did not synergize with allergen in cytokine production and histamine release. DEPex-induced basophil IL-4 expression peaked at 2 hours and persisted through 20 hours, in contrast to allergen-induced IL-4, which was transient. The effect of DEPex on basophil cytokine expression and histamine release was dose dependent and occurred with cells from both allergic and nonallergic subjects. DEPex induced IL-4 expression and histamine release in highly enriched basophil populations, suggesting it acts directly on basophils. Other peripheral blood leukocytes, including T cells, did not contribute to this cytokine expression. Preincubation with N-acetylcysteine completely abrogated DEPex-driven basophil IL-4 expression. CONCLUSIONS: Basophils are a direct target for DEPex, inducing IL-4 expression and histamine release in an IgE-allergen independent fashion. N-acetylcysteine inhibition of DEPex-driven IL-4 expression provides evidence that generation of reactive oxygen species is required for the effects observed. The capability of DEPex to activate basophils in both allergic and nonallergic subjects suggests a potential role of this pollutant in the increasing prevalence of allergic diseases. 相似文献
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Calman KC 《Medical teacher》2000,22(5):448-451
Specialist education and continuing professional development are likely to change considerably over the next 20 years. This will reflect the context within which medicine is practised. This will include changes in disease patterns, population structure, medical advances, information technology and, perhaps most powerfully, public involvement. In speciality education there will be a need to define more clearly both the role of the specialist, and the competences to be achieved. CPD is the longest period of education and, as such, it is the phase during which there is likely to be greatest change in clinical practice. There is a need to develop mechanisms to assure the public that doctors continue to practice up-to-date medicine, and that there is confidence and trust in the process. 相似文献
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Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis 相似文献
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B19 parvovirus is the etiologic agent of fifth disease and transient aplastic crisis. In natural infections, B19 antigen and DNA have been detected in sera early in the course of aplastic crisis and only rarely in fifth disease. We have found B19 DNA in circulating cells of infected patients by DNA dot blot with a virus-specific probe: in four of four sickle cell patients with aplastic crisis, in one asymptomatic sibling, and in one normal adult with fifth disease. Only two of the sera showed B19 DNA. High-molecular weight intermediate forms were detected by Southern analysis of DNA extracted from cells, thus indicating active replication of virus in cells rather than passive adsorption to their surface membranes. Separation of cells into high- and low-density fractions resulted in a concentration of the virus DNA in the granulocytic fraction. 相似文献
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