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21.
Differences in mortality from acute myocardial infarction between coronary care unit and medical ward: treatment or bias? 总被引:1,自引:0,他引:1
R Reznik I Ring P Fletcher V Siskind 《British medical journal (Clinical research ed.)》1987,295(6611):1437-1440
To analyse the effectiveness of coronary care units in reducing mortality from myocardial infarction 18 hospitals ranging from large urban teaching hospitals to small country hospitals were stratified into four levels of care. Previous analysis had failed to show significant differences in the overall mortality in hospital among levels. There were significant differences in mortality, however, between those patients allocated to be cared for in the coronary care unit and those in the medical wards in the more advanced hospitals. The differences were largest in the hospitals with the most elaborate facilities (level 1) and non-existent in those with the least (level 4). Several analytical approaches to these observed differences indicated that they were: (a) reduced by adjustment for age and severity of infarction; (b) paralleled by differences in coexisting disease recorded on death certificates; (c) no longer significant at level 1 after allowing for differences in coexisting disease; and (d) not significant at any level after exclusion of patients first diagnosed at necropsy. These findings suggest that the observed differences in mortality between coronary care units and medical wards are largely due to bias in selection and diagnosis. 相似文献
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23.
The qualities of a new measure of therapists' interventions, the Inventory of Therapeutic Strategies (ITS), were examined in cognitive and brief dynamic psychotherapy. In contrast to other inventories, the ITS focuses on three types of therapist intentions (exploratory, supportive, and work-enhancing), and it also takes into account the content and object of exploratory strategies. In this preliminary study, ITS categories were found 1) to be reliably rated, 2) to be unrelated to the therapist's contribution to the alliance, 3) to differentiate cognitive and dynamic psychotherapy, and 4) to predict outcome, alone or in interaction with the alliance. 相似文献
24.
J A Garson M Lenzi C Ring F Cassani G Ballardini M Briggs R S Tedder F B Bianchi 《Journal of medical virology》1991,34(4):223-226
Sera from 14 patients with type 2 autoimmune hepatitis (anti-LKM1 positive) were investigated for evidence of hepatitis C virus (HCV) infection. Antibodies to HCV were detected in 13 patients by both commercial and "in-house" ELISAs and also by a second generation recombinant immunoblot assay. Nine of the 13 (69%) anti-HCV positive patients were shown to be viraemic by a polymerase chain reaction-based assay for serum HCV RNA. Neither anti-HCV nor serum HCV RNA were detected in any of 6 controls with primary biliary cirrhosis or in 39 healthy blood donors. These findings strongly suggest a role for HCV in the pathogenesis of type 2 autoimmune hepatitis. 相似文献
25.
6 patients suffering from severe atopic dermatitis with high serum IgE were investigated. 3 of the patients had elevated plasma histamine levels (1.5-2.0 ng/ml). Compared to 9 nonatopic normal volunteers, the patient showed increased in vitro histamine release from peripheral leukocytes after stimulation with iothalamate and methacholine: while there was no significant histamine release at a methacholine concentration of 10(-4) M in normals, 4 of the patients with atopic dermatitis showed measurable histamine release under these conditions in vitro. The uptake of radiolabeled serotonin by platelets in vitro was decreased in 2 of the patients. There was no significant difference in serotonin release induced in vitro by different concentrations of thrombin, epinephrine and methacholine; 2 patients showed an increased platelet release reaction after iodipamide stimulation. It is concluded that a general tendency to release vasoactive mediators, even after 'nonimmunologic' stimulation, might play a role in the pathogenesis of atopic dermatitis. 相似文献
26.
Secretory immunoglobulin A and cardiovascular reactions to mental arithmetic, cold pressor, and exercise: effects of alpha-adrenergic blockade 总被引:6,自引:0,他引:6
The mechanism underlying acute changes in secretory immunoglobulin A (sIgA) remains to be determined. In this experiment, sIgA and cardiovascular activity were monitored at rest and while participants performed a mental arithmetic task, cold pressor, and submaximal cycle exercise following placebo or 1 mg of the alpha-adrenergic blocker, doxazosin. Under placebo, the tasks produced patterns of cardiovascular activity indicative of combined alpha- and beta-adrenergic, alpha-adrenergic, and beta-adrenergic activation, respectively. Doxazosin was associated with reduced blood pressure during cold pressor, but not during arithmetic or exercise. Mental arithmetic elicited increases in sIgA concentration and exercise produced increases in both sIgA concentration and secretion rate; these changes were unaffected by alpha blockade. In contrast, the cold pressor was associated with decreases in both sIgA concentration and secretion rate, which were blocked by doxazosin. These data suggest that acute decreases, but not increases, in sIgA are mediated by alpha-adrenergic mechanisms. 相似文献
27.
Neuroimmunologic aspects of skin inflammation involve several interacting systems. The modulating influence of autonomic and sensory nerves has been known for a long time. Neurokinines derived from these nerves have recently been shown to interact with antigen presentation in dermal Langerhans cells and other key functions of allergic skin disease. While some mechanisms of afferent function and local reflex are known, the nature of efferent effects (from brain to periphery) remains to be elucidated. New aspects include involvement of the brain-derived neurotrophic factor in addition to the autonomic nervous system in mental stress response and insight in the immunomodulation by proopiomelanocortins. Novel strategies for therapy and prevention of chronicity may also result from understanding the role of increased secretion of nerve growth factor in atopic eczema and psoriasis. 相似文献
28.
Cardiovascular and secretory immunoglobulin A reactions to humorous, exciting, and didactic film presentations 总被引:1,自引:0,他引:1
Harrison LK Carroll D Burns VE Corkill AR Harrison CM Ring C Drayson M 《Biological psychology》2000,52(2):113-126
Secretory immunoglobulin A (sIgA) in saliva and cardiovascular activity were measured at rest and in response to three film extracts varying in affective content. Subjective ratings of film impact confirmed a priori assumptions; the humorous film was rated as funnier than the other two films, the didactic film as more boring than the other two films, and the exciting film as more exciting and more stressful than the other two films. The films elicited distinct patterns of cardiovascular autonomic activity. The exciting film provoked changes characteristic of beta-adrenergic activation: increased systolic blood pressure (SBP); heart rate (HR); cardiac output (CO); and shortened pre-ejection period (PEP). The didactic film had little impact on cardiovascular activity. While an increase in total peripheral resistance (TPR) occurred, the humorous film was largely notable for a reduction in beta-adrenergic drive, as evidenced by reduced CO and a lengthening of PEP. In contrast to previous research reporting a rise in sIgA particular to humorous exposures, the sIgA secretion rate, although enhanced by exposure to the films, did not vary with film content. 相似文献
29.
The Guide to Clinical Preventive Services, prepared in 1989 by the U.S. Preventive Services Task Force, assesses the effectiveness of 169 types of preventive interventions. In 1990, the Association of Teachers of Preventive Medicine formed a panel to review the guide and recommend ways it could be used to enhance both undergraduate and postgraduate medical education. This paper outlines the panel's recommendations of the types of knowledge and attitudes on which postgraduate medical education in prevention should be built. Detailed recommendations are presented, based on the summary findings of the guide, for residency education in prevention. Implementation of these recommendations will integrate preventive services into the continuum of medical care. These recommendations are presented to achieve the goal of educating physicians to approach the total patient, putting the patient's health rather than the disease process in the forefront of primary medical care. 相似文献
30.
A selective inhibitor of thromboxane biosynthesis enhances immediate and inhibits late cutaneous allergic reactions in man 总被引:1,自引:0,他引:1
Thromboxanes may be involved in late cutaneous reactions (LCRs). A new selective inhibitor of thromboxane biosynthesis was studied for its effect on immediate skin test reactions (WFRs) and LCRs in nine adult nonatopic volunteers (open study) and eight adult atopic patients (double-blind study vs. placebo). WFRs and LCRs were elicited by intradermal injections of 25 micrograms of compound 48/80 and 200 IU of rabbit anti-human IgE antibodies, and the patients' receiving injections of 0.32, 1.6, 8, 40, and 200 IU of anti-IgE antibodies. Dazoxiben (100 mg orally three times once every 4 hr) increased the diameter of wheals (p less than 0.005 in volunteers; p less than 0.05 in six patients receiving no additional drug treatment), favored their dispersion (lymphangitis/pseudopodia), and caused systemic reactions (headache, chills) in at least two out of eight patients. Edema formation during LCRs was markedly depressed in 13 out of 16 persons. Flare diameter and erythemata during LCRs were not altered. These data suggest a role of thromboxanes and their natural antagonists (e.g., prostacyclin) in the regulation of allergic inflammatory processes. 相似文献