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C. T. Schrijvers J. P. Mackenbach J. M. Lutz M. J. Quinn M. P. Coleman 《British journal of cancer》1995,72(3):738-743
We studied the association between deprivation and survival from breast cancer in 29,676 women aged 30 and over who were diagnosed during the period 1980-89 in the area covered by the South Thames Regional Health Authority. The measure of deprivation was the Carstairs Index of the census enumeration district of each woman''s residence at diagnosis. We studied the impact of stage at diagnosis, morphology and type of treatment on this association, with the relative survival rate and the hazard ratio as measures of outcome. There was a clear gradient in survival, with better survival for women from more affluent areas. At all ages, women in the most deprived category had a 35% greater hazard of death than women from the most affluent areas after adjustment for stage at diagnosis, morphological type and type of treatment. In younger women (30-64 years), the survival gradient by deprivation category cannot be explained by these prognostic factors. In older women (65-99 years), part of the unadjusted gradient in survival can be explained by differences in the stage of disease: older women in the most deprived category were more often diagnosed with advanced disease. Other factors, so far unidentified, are responsible for the gradient in breast cancer survival by deprivation category. The potential effect on breast cancer mortality of eliminating the gradient in survival by deprivation category is substantial (7.4%). In women aged 30-64 years, 10% of all deaths within 5 years might be avoidable, while in older women this figure is 5.8%. 相似文献
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WINOCOUR PH; KALUVYA S; BROWN L; FARRER M; MILLAR JP; NEIL HAW; ALBERTI KGMM 《QJM : monthly journal of the Association of Physicians》1991,79(3):539-560
Hyperinsulinaemia is said to be a risk factor for cardiovasculardisease, but the extent to which different insulinaemic measuresare associated with vascular risk factors in ostensibly healthyindividuals, and whether they operate independently in men andwomen, remains uncertain. The association between risk factors and various insulinaemicmeasures was examined in 148 men and 118 women who were normoglycaemic,normotensive, and non-obese (body mass index in men <27,in women <25). A 75 g glucose tolerance test was administeredafter blood sampling for fibrinogen, lipids, lipoproteins andinsulin. Insulin was also measured after 1 and 2 hours. Significantunivariate correlations (p<0.01) were most consistently recordedbetween insulinaemic measures and fasting serum triglyceridesin men and women, whilst systolic blood pressure only correlatedwith insulinaemia in women, and diastolic blood pressure correlatedwith fasting and 2 hour insulinaemic measures in men and women.Inconsistent associations were noted with total serum cholesterolin men and women, with high density lipoprotein cholesterol,body mass index, apoprotein B and A1 in men, and with fibrinogenin women. Age was not correlated with any insulinaemic measurein men or women. Differences in vascular risk factors between quintiles of theinsulinaemic measures were examined, after correction for bodymass index. The dominant association with fasting and post-glucoseload insulinaemic measures was with triglycerides, especiallyin women, with less frequent graded differences between quintilesobserved for total cholesterol, and diastolic and systolic bloodpressures in men and women. The incidence of other risk factors often only differed in thelowest or highest quintile in comparison to other quintiles,suggesting a threshold rather than a graded effect. Furthermore,differences in HDL cholesterol and apoprotein B were only recordedfor top quintiles of post-glucose challenge/integrated insulinaemicmeasures in men, whilst serum fibrinogen concentrations onlydiffered significantly in women in the top insulinaemic areaunder the curve quintile. In the absence of additional risk factors such as diabetes,hypertension and obesity, insulinaemic measures are not consistentlyrelated to blood pressure and measures of lipid metabolism andcoagulation, and are thus a weak predictor of other cardiovascularrisk factors. The vascular risk profile associated with insulinappears somewhat different in apparently healthy men and women. 相似文献
14.
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
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Summary— Acidosis affects multiple steps in the excitation-contraction coupling pathway of myocardium, producing decreased calcium sensitivity of myofibrils and modification of the function of the sarcoplasmic reticulum. Our aim was to evaluate the effectiveness of three different classes of inotropic agents under acidotic conditions: 1) forskolin, an adenylate cyclase activator that enhances cellular cyclic AMP concentrations, 2) elevated extracellular Ca2+ and 3) endothelin-1, an activator of the inositol triphosphate, diacylglycerol pathway. Ferret papillary muscles were mounted in organ baths containing normal physiological solution (pH = 7.4). After baseline tension was measured, the muscles were bathed in an acidotic solution (pH = 6.98) that decreased tension to 40% of the control; subsequently, the muscles were washed with normal physiological solution until they returned to baseline. Each inotropic agent was added to the bathing solution in a concentration sufficient to increase tension by 40% above the baseline. Then the solution was made acidotic (pH = 6.98) in the continuous presence of that concentration of inotropic agent and the resultant steady-state developed tension measured. The increases in tension induced by each inotropic agent at normal pH were adjusted to be similar; in contrast, the response to each drug in acidosis was significantly different. Under acidotic conditions, endothelin-1 was the most effective inotropic agent in restoring the depressed developed tension. This was possibly due to enhancement of the myofilament sensitivity to Ca2+ , which was more effective than increasing [Ca2+ ]i through elevating extracellular Ca2+ or the addition of forskolin which increased [Ca2+ ]i but desensitized the myofilaments to Ca2+ . 相似文献
18.
Shared care: a review of the literature 总被引:7,自引:1,他引:6
This review examines broad issues of concern regarding the primary/secondarycare interface. The main purpose was to identify areas of goodpractice which could be adapted for more general use. One ofthe most fundamental aspects identified was communication, whichis discussed in some detail. Also covered are shared prescribingand disease management. The data suggest that the most effectivesystem(s) of shared care has yet to be established. Furtherqualitative and economic evaluations are required, taking intoaccount patient preferences. Although the literature does describecertain practice exemplars, it is clear that inter- and intra-professionalcommunication continues to be a problem. Whilst informationtechnology may provide some of the solutions, it is concludedthat a culture change, which compels health professionals tomake sharing of patient information a much higher priority,is reauired. Keywords. Shared care, seamless care, hospital, general practice, family practice. 相似文献
19.
J P Mackenbach C W Looman A E Kunst J D Habbema P J van der Maas 《Social science & medicine (1982)》1988,27(9):889-894
In order to assess the impact of medical care innovations on post-1950 mortality in The Netherlands, we analysed trends in mortality from a selection of conditions suggested by Rutstein et al.'s lists of "unnecessary untimely mortality". This selection covers 11 types of innovation, and includes 35 conditions which have become amenable to medical care. Loglinear regression analysis shows that for most of these conditions mortality declined during each of two subperiods (1950-1968; 1969-1984). Mortality decline accelerated in the second subperiod for many conditions. Reductions in mortality from these conditions between 1950/54 and 1980/84 added 2.96 and 3.95 years to life expectancy at birth of Dutch males and Dutch females respectively. A priori evidence indicates that these mortality reductions are due to some extent to 'spontaneous' incidence declines. Although the exact contribution of medical care innovations to these changes in mortality thus cannot be determined, the impact of medical care on post-1950 mortality in The Netherlands could well have been substantial. 相似文献
20.
Regional differences in mortality from conditions amenable to medical intervention in The Netherlands: a comparison of four time periods. 总被引:8,自引:7,他引:1 下载免费PDF全文
J P Mackenbach A E Kunst C W Looman J D Habbema P J van der Maas 《Journal of epidemiology and community health》1988,42(4):325-332
In The Netherlands, as in many other countries, important geographical variation in mortality from conditions amenable to medical intervention exists. Associations with a number of simple medical care supply characteristics (general practitioner density, hospital bed density, and percentage of regional hospital beds located in university and small hospitals) are generally weak and inconsistent, both before and after controlling for possible confounding factors. We explored one of the possible reasons for this lack of consistency, which is the time dependency of the relationship between medical care supply and avoidable mortality. A comparison of associations in four time periods (1950-54, 1960-64, 1970-74 and 1980-84) shows that the percentage of variance in regional mortality levels which can be "explained" by the medical care supply variables has changed over time. Although the patterns of change differ little from what one would expect on the basis of the time of introduction of medical care innovations, the exact nature of the associations is puzzling. Apart from some expected negative associations between mortality and the presence of university hospitals, we also found a few unexpected positive associations with general practitioner density. Possible explanations for these findings are discussed, and it is concluded that further study is necessary to reveal the causes of a higher or lower mortality level for conditions considered to be amenable to medical intervention. 相似文献