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Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce.  相似文献   
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Despite the advances of microsurgery, endocrinology, radiation therapy, and neuroimaging over the last half-century, craniopharyngiomas continue to present neurosurgeons with a therapeutic dilemma. The tumor's histologic benignity belies its aggressive biologic behavior. Although total resection is theoretically curative, the cost in terms of functional disability can be high, especially in light of reports describing long-delayed tumor recurrences ("false cure"). As in other intracranial neoplasms, multimodality therapy is often necessary over the course of a patient's lifetime. Stereotactic techniques (intracystic irradiation, radiosurgery, cyst aspiration, biopsy) have a well-established role in selected cases. To maximize preservation of neurologic, visual, and hypothalamic-pituitary functions, the application of stereotactic, microsurgical, or external irradiation techniques in an individual patient must take into account all of the patient's prior treatments as well as the current status of his or her tumor. Our current recommendation for multimodality treatment of craniopharyngiomas is illustrated in Figure 5. Stereotactic surgery has a definitive role in the life-long management of some patients, and plays an important adjunctive role in many others.  相似文献   
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To assess the long-term risk of facial nerve dysfunction after unilateral acoustic tumor stereotactic radiosurgery, we retrospectively analyzed our initial experience in 98 unilateral acoustic tumor patients who were evaluated at least 2 years after treatment. This observation interval permits an analysis of both the risk of onset and the potential for recovery of facial nerve function. The overall risk of developing any degree of delayed transient or permanent postoperative facial neuropathy was 21.4% (21 of 98 patients). Only one patient undergoing radiosurgery alone had poor residual facial nerve dysfunction worse than House-Brackmann grade III. Normal facial nerve function (House-Brackmann grade 1) was preserved in 95% of patients with small tumors (10 mm or less petrous-pons dimension) and in 90% of patients who had useful hearing and normal facial function preoperatively. Normal facial function was preserved in all patients with intracanalicular acoustic tumors. The risk of delayed facial neuropathy was reduced by performing radiosurgery when tumors were small (1000 mm(3) or less), by enclosing the tumor within the 50% isodose volume, by using multiple small radiation isocenters, and by detailed identification of the tumor volume using stereotactic magnetic resonance imaging.  相似文献   
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Adjuvant stereotactic radiosurgery for anaplastic ependymoma   总被引:2,自引:0,他引:2  
OBJECT: The purpose of this retrospective study is to evaluate the role of stereotactic radiosurgery using the Gamma Knife as an adjuvant to other modalities used in the treatment of malignant ependymomas of both children and adults and to assess its efficacy in terms of tumor control and overall survival. METHOD: Between 1987 and 1998, 22 patients in the age range of 1.5-65 years (mean age 22. 3) with progressive anaplastic ependymoma were treated by stereotactic radiosurgery using the 201 source Co-60 Leksell Gamma Knife at the University of Pittsburgh. The irradiated tumor volume varied from 0.84 to 36.8 cm(3) (mean 13.7). The median dose delivered to the tumor margin was 16.1 Gy (range 10-20), and the mean maximal dose was 32.2 Gy (range 20-40). The disease-free survival, the tumor control rate and the overall survival were recorded to evaluate the efficacy of radiosurgery. The median follow-up from radiosurgery was 21 months (range 4-84). RESULTS: Median survival after radiosurgery was 2.2 years (46.6 +/- 12.1% 5-year actuarial). Median survival from the initial diagnosis was 10. 1 years (50.3 +/- 12.5% at 5 years, 37.7 +/- 14.4% at 10 years). Reduction or stabilization of the treated tumor was seen in 16 out of 22 (68%) patients. Forty-one percent of the patients eventually developed delayed distant cerebral recurrence outside the treated volume. The 5-year actuarial rates for local control and cranial control at any location were 62.3 +/- 13.6% and 32.4 +/- 10.8%, respectively. No complication occurred as a side effect of radiosurgery. CONCLUSION: For patients with locally recurrent or progressive anaplastic ependymomas, Gamma Knife stereotactic radiosurgery proved to be safe and effective as a salvage adjuvant therapy to achieve local tumor control and improve survival.  相似文献   
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The radiobiology of radiosurgery   总被引:3,自引:0,他引:3  
Radiosurgery is the precise and complete destruction of a chosen target containing healthy or pathological cells, without significant concomitant or late radiation damage to adjacent cells. This article discusses briefly the many uses of radiobiology and considers variables in the treatment, such as dose rate, dose homogeneity, and the issue of possible pharmacological radioprotection for radiosurgery. Comparisons between radiosurgery and fractionation are also made.  相似文献   
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Every neurosurgeon can appreciate Dandy's recognition that the drainage of brain abscesses causes trauma to the delicate parenchyma. Over the years, brain surgery has evolved toward management of problems by using less and less invasive techniques and thus gaining ever lower morbidity. Clearly, the advent of better imaging techniques has improved the outcome in patients afflicted with intracerebral infections. The combination of stereotaxy with these imaging techniques is contributing a "zero mortality" in the treatment of these infections. In our series of 29 consecutive patients with non-AIDS-related infections, no patient died as a direct result of a stereotactic surgical procedure. Two patients (7%) had new neurologic deficits after surgery. The only patient left with a permanent disability had a kidney allograft and subacute bacterial endocarditis. His condition deteriorated 6 hours after aspiration of a sterile abscess, when an intra-abscess hematoma was diagnosed and evacuated. In retrospect, this complication may have been avoided by less vigorous aspiration. Three of the four patients with nonviral infections who died were iatrogenically immunosuppressed for their organ transplants. These patients are difficult to treat, and given the current popularity of transplantation procedures, neurosurgeons will face more and more opportunistic infections. In general, the patients with abscesses did well. On the other hand, nonoperative mortality was extremely high for patients with viral encephalitides. This high mortality may have resulted from a delay in diagnosis and treatment or from the unavailability of highly effective antiviral agents at the time the biopsies were performed. The importance of early diagnosis and treatment of infection cannot be overemphasized. T.H. Flewett's warning about the management of HSE applies to the management of all cerebral infections: "It seems clear from everybody's published results [in the papers already given] if we wait to do biopsy until the clinical indications are unmistakable, we have waited so long that the patient, if he survives, will be left a severe neurological cripple." Because it is relatively noninvasive, stereotactic neurosurgery has been used increasingly to diagnose brain masses in patients with AIDS. We recommend its use for establishing diagnoses in all suspected cases of cerebral infection. We agree with Rosenblum et al: Empiric treatment of brain infections should be regarded as "radical." Such treatment should be reserved for patients who have an identifiable source of infection and causative organism or for patients who are clinically too unstable to undergo surgery.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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