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971.
972.
973.
BackgroundSymptoms are important drivers for the use of primary care services. Strategies aimed at shifting the focus away from the GP have broadened the range of primary healthcare available.AimTo explore preferences for managing symptoms and investigate trade-offs that the public are willing to make when deciding between different primary care services.MethodA discrete choice experiment examined management preferences for three symptoms of differing seriousness (diarrhoea, dizziness, and chest pain). Willingness-to-pay estimates compared preferences between symptoms, and by sex, age, and income.ResultsPreferences differed significantly between symptoms. ‘Self-care’ was the preferred action for diarrhoea and ‘consulting a GP’ for dizziness and chest pain. ‘Waiting time’ and ‘chance of a satisfactory outcome’ were important factors for all three symptoms, although their relative importance differed. Broadly, people were more prepared to wait longer and less prepared to trade a good chance of a satisfactory outcome for symptoms rated as more serious. Generally, preferences within subgroups followed similar patterns as for the whole sample, although there were differences in the relative strength of preferences.ConclusionDespite increased choices in primary care, ‘traditional’ actions of ‘self-care’ for minor symptoms and ‘GP consultation’ for more serious symptoms were preferred. The present findings suggest, however, that people may be willing to trade between different health services, particularly for less serious symptoms. Understanding the relative importance of different factors may help inform interventions aimed at changing management behaviour or improving services.  相似文献   
974.
The ability of exercise radionuclide ventriculography to detect multivessel coronary artery disease in patients who survived a single myocardial infarction was assessed. Seventy-four patients who had had myocardial infarction at least 8 weeks earlier underwent cardiac catheterization and exercise radionuclide ventriculography. Thirty-eight patients had had an inferior infarction: 25 with multivessel disease and 13 with single vessel disease of the right coronary artery. Thirty-six patients had had an anterior infarction: 26 with multivessel disease and 10 with single vessel disease of the left anterior descending coronary artery.

Among patients with anterior infarction there was no significant difference between patients with single vessel disease and patients with multivessel disease with regard to resting ejection fraction, exercise ejection fraction, and the mean change from rest to exercise. Patients with single vessel disease had a decrease in ejection fraction from rest to exercise of 2.2 ± 2.7% units (mean) ± standard error [SE]), compared with a decrease of 5.4 ±1.3% units in those with multivessel disease (p = not significant [NS]). Seventeen of 26 (65%) patients with multivessel disease and 6 of 10 (60%) with single vessel disease had a decrease in ejection fraction of at least 5 percentage units (p = NS).

In patients with inferior infarction there was no difference in the mean resting ejection fraction in those with single vessel disease (53 ± 2%) compared with those with multivessel disease (50 ±2%); however, the mean exercise ejection fraction in patients with single vessel disease (57 ± 3%) was significantly higher (p < 0.005) than that in patients with multivessel disease (45 ± 2%). Sixteen of the 25 patients with multivessel disease (64%) but only 1 patient with single vessel disease (7.7%) had a decrease in ejection fraction of at least 5 percentage units (p < 0.001).

A new wall motion abnormality developed in 8 patients with anterior infarction and 11 with inferior infarction with multivessel disease and none with single vessel disease. The sensitivity and specificity in predicting multivessel disease using the criteria of the development of a new wall motion abnormality or a decrease in ejection fraction with exercise of at least 5 percentage units were 80 and 92% for the patients with inferior infarction, but only 69 and 40% for the patients with anterior infarction.

These results suggest that exercise radionuclide angiography can be used to discriminate between single and multivessel disease after inferior myocardial infarction. For patients with anterior infarction, only a new abnormality in wall motion accurately predicts multivessel disease, but this occurred in only one third of such patients.  相似文献   

975.
Detection and estimation of the degree of chronic aortic insufficiency with pulsed Doppler echocardiography was attempted in 27 patients documented to have aortic insufficiency on aortography. Twenty-five patients had associated aortic stenosis or mitral valve disease, or both. A disturbed diastolic flow within the left ventricular outflow tract was recorded in all but one patient (Doppler sensitivity 96 percent). Aortic insufficiency was clinically undetected In three patients (clinical sensitivity 89 percent). In a small number of patients Doppler echocardiography also appeared to be highly specific for this disorder. The Doppler technique estimated the degree of aortic Insufficiency by assessing the distribution of diastolic flow within the outflow tract and the body of the left ventricle. A significant correlation between the Doppler method and the angiographic estimation of aortic insufficiency was found (r = 0.88, p < 0.01).  相似文献   
976.
Combined portal and mesenteric vein thrombosis preventing restoration of adequate portal venous flow has been considered a contraindication to liver transplantation. We report a patient with failed splenorenal (SR), portocaval (PC), and mesocaval (MC) shunts, who despite the absence of any obvious means for supplying portal venous inflow to a hepatic graft, successfully underwent orthotopic liver transplantation. A method of reconstruction of the portal vein with the use of vein grafts anastomosed to a large splanchnic venous collateral is described. This technique can be used in selected patients in whom orthotopic liver transplantation might otherwise be considered technically impossible.  相似文献   
977.
Adults and children have differences in their susceptibility to schistosomiasis. The relative influences of age-dependent innate resistance and acquired immunity in the differences between susceptibility to schistosomiasis are difficult to assess in humans. Therefore, we exposed juvenile and adult female rhesus monkeys to primary infection with Schistosoma mansoni. In contrast to the adult animals, the juvenile rhesus monkeys had low levels of interleukin (IL)-4 and IL-5 production by peripheral blood mononuclear cells after schistosome infection, as well as lower levels of parasite-antigen-specific antibody (IgG, IgM, and IgA) responses, and produced limited antigen-specific or total IgE. Juvenile animals had statistically nonsignificant increased worm burdens and tissue or fecal egg counts, compared with that of adults, whereas circulating schistosome antigens were significantly higher in infected juvenile monkeys. These results suggest that juvenile rhesus monkeys have reduced type 2 cytokine responses after primary schistosome infections and perhaps are more susceptible to parasite infection.  相似文献   
978.
OBJECTIVE: To assess the relative contribution of constitutional (individual) factors, pre-accident health, psychological and workplace psychosocial factors, and accident related (mechanical) factors in the development of neck pain (whiplash) following a motor vehicle accident. METHODS: We conducted a case-control study of drivers (ages 17-70 yrs) who reported a motor vehicle accident to their insurance company. A self-report mailed questionnaire retrospectively collected information on the driver's pre- and post-accident health, details of the accident, and other exposure data. Case/control status (post-accident neck pain) was ascertained using a preshaded manikin. RESULTS: In total, 26% of drivers reported post-accident neck pain. Women, younger individuals, and those with a history of neck pain were more likely to report neck pain following their accident (OR 1.50, 95% CI 0.98, 2.28; OR 1.62, 95% CI 0.96, 2.74; OR 1.75, 95% CI 1.09, 2.81, respectively). In addition, a number of accident related and psychosocial factors were independently associated with reporting post-accident neck pain: collision from behind (OR 2.55, 95% CI 1.41, 4.62); vehicle stationary at impact (OR 1.93, 95% CI 1.12, 3.33); collision severity (upper vs lowest tertile: OR 16.1, 95% CI 8.64, 30.1); not being at fault (OR 2.61, 95% CI 1.49, 4.59); and monotonous work (OR 2.19, 95% CI 1.19, 4.04). Based on these 8 factors, the likelihood of having neck pain increased from 7% with < or = 2 risk factors to 62% with > or = 5. CONCLUSION: Development of neck pain after a motor vehicle accident is a complex phenomenon resulting from the combined effects of constitutional, mechanical, and psychosocial factors. Using 8 such variables it is possible to identify those at high risk of developing neck pain.  相似文献   
979.
BACKGROUND: Altered noradrenergic neurotransmission is associated with depression and may contribute to drug abuse and alcoholism. Differential initial sensitivity to ethanol is an important predictor of risk for future alcoholism, making the inbred long-sleep (ILS) and inbred short-sleep (ISS) mice a useful model for identifying genes that may contribute to alcoholism. METHODS: In this study, molecular biological, neurochemical, and behavioral approaches were used to test the hypothesis that the norepinephrine transporter (NET) contributes to the differences in ethanol-induced loss of righting reflex (LORR) in ILS and ISS mice. RESULTS: We used these mice to investigate the NET as a candidate gene contributing to this phenotype. The ILS and ISS mice carry different DNA haplotypes for NET, showing eight silent differences between allelic coding regions. Only the ILS haplotype is found in other mouse strains thus far sequenced. Brain regional analyses revealed that ILS mice have 30 to 50% lower [3H]NE uptake, NET binding, and NET mRNA levels than ISS mice. Maximal [3H]NE uptake and NET number were reduced, with no change in affinity, in the ILS mice. These neurobiological changes were associated with significant influences on the behavioral phenotype of these mice, as demonstrated by (1) a differential response in the duration of ethanol-induced LORR in ILS and ISS mice pretreated with a NET inhibitor and (2) increased ethanol-induced LORR in LXS recombinant inbred (RI) strains, homozygous for ILS in the NET chromosomal region (44-47 cM), compared with ISS homozygous strains. CONCLUSIONS: This is the first report to suggest that the NET gene is one of many possible genetic factors influencing ethanol sensitivity in ILS, ISS, and LXS RI mouse strains.  相似文献   
980.
Epstein-Barr virus (EBV) latent infection membrane protein 1 (LMP1)-induced NF-kappaB activation is important for infected cell survival. LMP1 activates NF-kappaB, in part, by engaging tumor necrosis factor (TNF) receptor-associated factors (TRAFs), which also mediate NF-kappaB activation from LTbetaR and CD40. LTbetaR and CD40 activation of p100/NF-kappaB2 is now known to be NIK/IKKalpha-dependent and IKKbeta/IKKgamma independent. In the experiments described here, we found that EBV LMP1 induced p100/NF-kappaB2 processing in human lymphoblasts and HEK293 cells. LMP1-induced p100 processing was NIK/IKKalpha dependent and IKKbeta/IKKgamma independent. Furthermore, the LMP1 TRAF-binding site was required for p100 processing and p52 nuclear localization, whereas the LMP1 death domain-binding site was not. Moreover, the LMP1 TRAF-binding site preferentially caused RelB nuclear accumulation. In murine embryo fibroblasts (MEFs), IKKbeta was essential for LMP1 up-regulation of macrophage inflammatory protein (MIP)-2, TNFalpha, I-TAC, ELC, MIG, and CXCR4 RNAs. Interestingly, in IKKalpha knockout MEFs, LMP1 hyperinduced MIP-2, TNFalpha, and I-TAC expression, consistent with a role for IKKalpha in down-modulating canonical IKKbeta activation or its effects. In contrast, LMP1 failed to up-regulate CXCR4 and MIG RNA in IKKalpha knockout MEFs, indicating a dependence on noncanonical IKKalpha activation. Furthermore, LMP1 up-regulation of MIP-2 RNA in MEFs was both IKKbeta- and IKKgamma-dependent, whereas LMP1 upregulation of MIG and I-TAC RNA was fully IKKgamma independent. Thus, LMP1 induces typical canonical IKKbeta/IKKgamma-dependent, atypical canonical IKKbeta-dependent/IKKgamma-independent, and noncanonical NIK/IKKalpha-dependent NF-kappaB activations; NIK/IKKalpha-dependent NF-kappaB activation is principally mediated by the LMP1 TRAF-binding site.  相似文献   
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