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BACKGROUND: Malignant hemangioendothelioma of the thyroid is a rare tumor predominantly described in areas with endemic goiter like the Alpine regions. The estimated incidence of the disease is between 0.15 and 0.25 per 100,000 inhabitants per year for Western Austria. The prognosis is reported to be dismal. MATERIALS AND METHODS: Between 1982 and 1995, 10 cases with immunohistochemically confirmed malignant hemangioendotheliomas of the thyroid were referred to our department for postoperative or palliative treatment. Two patients with clear margins at surgery received no adjuvant radiotherapy and were only observed. By surgery, clear margins (R-0 resection) were achieved in 5, microscopic residuals (R-1) were left in 3, and gross residual disease in 1 patient. One patient had an inoperable primary tumor. Postoperative radiotherapy was administered in 6 cases, 4 of them additionally received the radiosensitizer razoxane. Total tumor doses ranged between 58 and 65 Gy. RESULTS: Local tumor control was achieved in 9 of 10 patients; 4 of 10 lived longer than 4 years. The median survival time has not yet been reached and is presently between 7.5 and 21+ months.--Noteworthy is a complete regression of 2 lung metastases in a 72-year-old man by a combination of vindesine, razoxane and radiotherapy. The patient is still in complete remission under a maintenance therapy with vindesine and razoxane since 14 months.--It may also be of interest that 4 of the 10 patients were strongly exposed to vinyl chloride and other polymeric materials during their occupational life. CONCLUSIONS: This small series may indicate that the outcome of this disease may not be uniformly deleterious, and that the resistance to radiotherapy reported in the literature may be questioned.--The data offer new evidence of the occurrence of vinyl chloride-induced angiosarcomas outside the liver, and support observations which have already been published in case reports.  相似文献   
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This article discusses the role of the newer lipid lowering agents (statins and fibrates) for the treatment of hyperlipidemias in military aviators. Special emphasis will be on long-term safety and the effects of these drugs on CNS functions pertinent to aviators. We propose that these new lipid lowering agents, such as hydrophilic statins and newer fibrates are reasonably safe in aviators with restricted flying duties, subject to long-term surveillance by a specialist.  相似文献   
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Whether late positive components of event-related potentials (ERPs) parallel changes in heart rate (HR) indicative of attention/orienting to rare stimuli has been debated. In the present study, a three-stimulus design was used, with rare target, rare nontarget, and frequent standard stimuli delivered under identical conditions except that instructions to subjects described the targets to which subjects should respond but did not describe the nontargets. In Experiment 1, stimuli varied among modalities; in Experiment 2, auditory stimuli were employed. Both ERPs and HR were consistent with automatic processing preceding two stages of controlled processing. Rare stimuli evoked larger parietal P300 and initial HR deceleration than standards. Presumably because of load-reducing effects of long interstimulus intervals, targets and nontargets were not distinguished before a late slow wave and a late phase of HR acceleration. Neither rare stimulus elicited a recognizable frontal P3a.  相似文献   
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The surgical principles for the reduction operation of the female breast were established in numerous publications during the last decades. Improvement of results can be obtained in our opinion only by refinement of previous described techniques. We are describing the operation for mammahyperplasia designed in this institution which contains modified steps of Stroembeck, Biesenberger and McKissock technique. The cosmetic results are acceptable and the complications of slough of the nipples is greatly reduced.  相似文献   
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When the procedure is held constant within an experimental session, responding often changes systematically within that session. Many of these within-session changes in responding cannot be dismissed as learning curves or by-products of satiation. They have been observed in studies of positive reinforcement, avoidance, punishment, extinction, discrimination, delayed matching to sample, concept formation, maze and alley running, and laboratory analogues of foraging, as well as in the unconditioned substrates of conditioned behavior. When aversive stimuli are used, responding usually increases early in the session. When positive reinforcers are used, responding changes in a variety of ways, including increasing, decreasing, and bitonic functions. Both strong and minimal reinforcement procedures produce within-session decreases in positively reinforced behavior. Within-session changes in responding have substantial theoretical and methodological implications for research in conditioning.  相似文献   
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