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51.
The main goal of the present work was to longitudinally examine consequences of long‐term moderately elevated levels of stress for various health outcomes. To address this issue, data covering 10 years was used from the ongoing Swedish population‐based prospective Betula Study. Based on the ratings on a validated self‐reported stress scale, matched subsamples between 40 and 65 years of age were divided into a high (n = 137) and low (n = 211) stress group. The reported incidence of cardiovascular, diabetes, psychiatric, tumour and musculoskeletal diseases was assessed 5 and 10 years after baseline (baseline = 1993–1995) without contaminating effects of past health history. The incidence of diseases 5 years after baseline assessment showed no differences between the groups. After 10 years, there was a significantly higher incidence of psychiatric diseases, mainly depression in the high‐stress group as well as a significant effect for tumours, although the number of cases was low. Although moderately elevated stress level may have a possible impact on psychiatric diseases especially depression and some tumours, it seems that prolonged moderate stress does not appear to be harmful to other stress‐related diseases. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
52.
Aims and Methods: The pulmonary and vascular effects of endothelin‐1 receptor activation were studied in isolated perfused and ventilated lung preparations from rat. The responses to endothelin‐1 (ET‐1) and the endothelin B (ETB) receptor agonist sarafotoxin 6c (S6c) were characterized using the endothelin A (ETA)‐receptor antagonist FR 139317, the ETB‐receptor antagonist BQ 788 and the combined ETA/ETB‐receptor antagonist Bosentan. The respiratory parameter airway conductance (Gaw) and the vascular parameter perfusion flow were analysed simultaneously. Results: Concentration–response curves for ET‐1 administered intra‐arterially revealed that its most potent effect was on the vascular side while S6c had a more potent effect on airway conductance. ET‐1, given as a bolus dose intra‐arterially (100 μL of 0.2 nm ), induced a strong‐ and long‐lasting contraction of the vasculature while only a less pronounced contraction was seen in the airways. Neither of the antagonists had a significant effect per se on Gaw or perfusion flow. FR 139317 reduced the effect of ET‐1 on perfusion flow by about 50%, while airway conductance was augmented. BQ 788 enhanced the decrease in perfusion flow by ET‐1 while Gaw was not influenced. The combined ETA/ETB antagonist Bosentan powerfully prevented the ET‐1‐induced decrease in Gaw but did not alter its reduction in perfusion flow. Conclusions: The potent effect of ET‐1 on the vascular side of the lung is mediated mainly through ETA receptors, whereas both ETA and ETB receptors are involved in Gaw in the rat lung.  相似文献   
53.
BACKGROUND CONTEXT: Methylprednisolone has evolved during the 1990s, through the results obtained from the National Acute Spinal Cord Injury Studies NASCIS II and III, as a standard treatment in acute spinal injury. PURPOSE: To evaluate the scientific basic for the use of methylprednisolone in acute spinal cord injury. STUDY DESIGN: Systematic review of the accumulated literature. METHODS: Critical evaluation of the data obtained in the NASCIS II and III studies plus other accumulated literature. RESULTS: Analyses have been made on subgroups of the study populations, and the results were based on statistical artefacts. Furthermore, improved functional recovery shown by these studies was not clinically significant. CONCLUSION: There is insufficient evidence to support the use of methylprednisolone as a standard treatment in acute spinal cord injury.  相似文献   
54.
Deck officers on coastal tankers may be exposed to high concentrations of cargo vapors during loading and tank-cleaning operations. Two cases of acute nonlymphatic leukemia are described. Both men had worked as chief officers on coastal tankers transporting benzene and other petroleum products.  相似文献   
55.
Endotoxins in cardiopulmonary bypass   总被引:5,自引:0,他引:5  
Endotoxins are biologically active substances derived from the cell wall of degraded gram-negative bacteria. Since sterile water may also contain large amounts of endotoxins, these are easily introduced into the manufacturing processes of technical medical material, such as the extracorporeal components used in cardiopulmonary bypass. In hemodialysis, the presence of endotoxins has been related to untoward effects in patients. Using the limulus amebocyte lysate test, we determined the serum concentration of endotoxin in 42 patients undergoing coronary bypass operations. The values increased during cardiopulmonary bypass, exceeding the normal range of 0 to 20 ng/L in 10 patients with a maximum of 82 ng/L, which probably indicates endotoxin release from the extracorporeal equipment. We found no obvious relation to postoperative morbidity. The endotoxin levels of this study are considerably lower than those reported in two other studies of patients having cardiopulmonary bypass. This might be due to less intraoperative contamination but possibly also to differences in analytic methods.  相似文献   
56.
Cancer survival in Estonian migrants to Sweden.   总被引:2,自引:0,他引:2       下载免费PDF全文
OBJECTIVE: To quantify the eventual extra loss of life incurred to cancer patients in Estonia compared with those in Sweden that was possibly attributable to differences in society. DESIGN: Population based survival of cancer patients in Estonia was compared with that of Estonian immigrants to Sweden and that of all cancer patients in Sweden. The cancer sites studied were female breast and ovary, male lung and prostate, and male and female stomach and colon. SETTING: Data on incident cases of cancer were obtained from the population based Swedish and Estonian cancer registries. PARTICIPANTS: Data from Estonian patients in Sweden, Estonian patients in Estonia, and patients from the total Swedish population were included in the study. MAIN RESULTS: Differences in survival among the three populations, controlling for follow-up time and age at diagnosis, were observed in breast, colon, lung, ovarian, and prostate cancers. The survival rates of Estonians living in Sweden and the total population of Sweden were better than that of the Estonians living in Estonia. For cancers of the breast and prostate, the excess mortality in the older age group (75 and above) was much greater in Estonia than in the other populations. CONCLUSIONS: Most differences in cancer survival between Estonian and Swedish populations studied could be attributed to a longer delay in diagnosis, and also to inferior treatment (including access to treatment) in Estonia compared with Sweden. Estonia's lag in socioeconomic development, particularly in its public health organisation and funding, is probably the main source of the differences observed.  相似文献   
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Numerous ritual acts involving the skull result in orofacial changes. The present study focuses on ritual acts of Brazilian Zoé Indians. A distinct deformation effect of the ritual act (wearing a lip-plug) on the morphology of the orofacial system is demonstrated and documented using jaw models. The studies show that the lip-plug significantly influences tooth position and jaw growth. While the maxilla displays palatal displacement of the lateral incisors and elevation of the palate, retraction occurs in the mandible depending upon plug size. Additionally, both the plug and the nutritional habits of the Indians induce marked abrasion of all teeth. Moreover, it is shown that the duration of lip-plug wear is an essential determinant of sustained orofacial changes.  相似文献   
60.
A fluorometric microculture cytotoxicity assay was employed for the study of cyclosporin A induced cytotoxicity in tumor samples from patients with B type chronic lymphocytic leukemia (B-CLL). Tumor cells from patients with B-CLL were found to be significantly more sensitive to the cytotoxic actions of cyclosporin A than normal blood mononuclear cells and tumor cells obtained from patients with different types of acute leukemia and solid tumors. The effect of cyclosporin A on B-CLL samples could be reproduced by a non-immunosuppressive cyclosporin A analogue. One B-CLL patient treated with cyclosporin A responded with a significant decrease in tumor mass and alleviation of anemia and B symptoms. The results show that cyclosporin A and its non-immunosuppressive analogues appear selectively toxic to B-CLL cells, an observation which may have clinical implications.  相似文献   
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