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Risk factors of system clotting in heparin-free haemodialysis 总被引:2,自引:2,他引:0
Heparin-free haemodialysis must be considered for all dialysis patients with a risk of haemorrhage. This technique is associated with increased danger of system coagulation with a blood loss of up to 250 ml. In 84 patients with a risk of haemorrhage, 296 heparin-free haemodialyses were recorded prospectively. First signs of coagulation were found very much more frequently in the venous airtrap than in the dialyser (146 vs 42). System coagulation occurred in 13 of the 296 dialyses (4%) and was prevented by prophylactic switching of the system and dialyser in 140 dialyses (47%). The time of system coagulation was on average 1.8 hours (+/- 0.2) after the beginning of dialysis. The 13 patients with system coagulation had a reduced blood flow on dialysis (217 +/- 52 vs 240 +/- 36 ml/min). Their initially normal clotting time (12 +/- 5 vs 14 +/- 4 min) was more significantly shortened after 2 h (4 +/- 3 vs 8 +/- 3 min). The activities of antithrombin III (87 +/- 34% vs 88 +/- 39%) and protein C (66 +/- 45% vs 59 +/- 37%) do not differ from those of 47 other patients, even at the time of system coagulation, as measured in five patients (92 +/- 34% for antithrombin III, 51 +/- 29% for protein C). System coagulation and shortening of clotting time thus cannot be regarded as a consequence of absorption of these inhibitory factors of plasmatic coagulation. The danger of system coagulation in heparin-free haemodialysis could probably be further reduced by an improvement of the biocompatibility of systems (airtrap) and dialysers (less activation of thrombocytes). 相似文献
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D C Holmes W R Grigsby V K Goel J C Keller 《The International journal of oral & maxillofacial implants》1992,7(4):450-458
Using the finite element method, this study modeled a 4.0 x 13.0-mm IMZ implant, restored with a cast gold crown, to examine the influence of the polyoxymethylene (POM) intramobile element (IME) on the transmission of vertical and oblique forces. Stress concentrations in the bone and in components of the implant system were much greater under a 30-degree load than under an equal vertical load. Stress transmission to bone occurred chiefly in the crestal region, and these stresses were not reduced when the IME was modeled in POM rather than in titanium. Maximum stress concentrations occurred in the fastening screw. 相似文献
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Relationships between serum cholesterol and coronary heart disease (CHD) were investigated in Tecumseh men and women who were 45 to 92 years old and initially free of CHD. Recruitment continued through three cycles of examinations over a period of 10 years, beginning in 1959. Follow-up for mortality ended in 1986 to 1987. Age-adjusted relative risks for CHD death for cholesterol levels of 5.2 to 6.2 mmol/L and greater than 6.2 mmol/L, compared with levels less than 5.2 mmol/L for men aged 45 to 64 years, were 1.2 and 1.7; for older men they were 1.0 and 1.8. Comparable relative risks for CHD death by cholesterol level were .7 and 1.4 for 45- to 64-year-old women and .8 and .7 for older women. Coefficients for cholesterol were significant for fatal CHD in men under and those 65 years and older when age, systolic blood pressure, body mass index, cigarette smoking status, and glucose intolerance were controlled in proportional hazards models. Cholesterol was a significant predictor of fatal CHD plus nonfatal myocardial infarction in middle-aged, but not elderly women. Relative risks for total mortality were lowest for middle-aged men and women with cholesterol levels of 5.2 to 6.2 mmol/L and the difference was significant in men. 相似文献
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R Keller 《Zentralblatt für Chirurgie》1992,117(5):267-269
103 patients with recurrent or persistent pneumothorax have been treated with local application of fibrin and talcum by a thoracoscopic procedure. The method was successful in 97 patients (94.2%) and lead to a stable and complete reexpansion of the lung within 6.3 days. As a direct consequence of the procedure itself only a few and minor complications occurred during a mean hospitalization-time of 10.4 days. The longterm followup over a mean period of 6.4 years revealed a recurrence rate of 15%, although half of the episodes occurred early during the first three months. After 6 years, 80% of the patients were completely asymptomatic and spirometric lung function was restored to normal values. We therefore consider thoracoscopic pleurodesis to be a successful and safe method for treating complicated pneumothorax. 相似文献
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E T Keller 《Cancer》1992,70(9):2334-2337
BACKGROUND. Autoimmune diseases and neoplasia have been associated as occurring simultaneously in individuals. This study evaluated the association between the simultaneous occurrence of canine lymphoma and various immune-mediated diseases. METHODS. The Veterinary Medical Data Program, a national disease data registry for veterinary schools, was examined. The following immune-mediated disease categories were evaluated: lupus disorders, pemphigus disorders, autoimmune polyarthritis, immune-mediated hemolytic anemia, and immune-mediated thrombocytopenia. Odds ratios with 99% confidence intervals were calculated for the occurrence of lymphoma and each of the immune-mediated disorder categories. RESULTS. Only dogs with immune-mediated thrombocytopenia had a statistically significantly increased odds ratio (5.61; 99% confidence interval, 4.16-7.57) for the occurrence of lymphoma versus the general population. This association still was observed for immune-mediated thrombocytopenia when stratified by age, sex, and neutering status. CONCLUSION. Dogs with immune-mediated thrombocytopenia had a greater occurrence of lymphoma than dogs without immune-mediated thrombocytopenia. 相似文献