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Randomized controlled trials (RCTs) on the topic of physical training and blood coagulation are rare and the effects are unclear. The aim of this study was to investigate whether endurance training adjusts blood coagulation and fibrinolysis at rest and after exercise. The study included 50 healthy untrained non-smokers randomized into training (TR 49 ± 6 years) or control group (CO 48 ± 6 years). Each subject performed an exercise test adjusted at 80 % individual anaerobic threshold (IAT) for 60 min before and after 12 weeks (80 % IAT: before TR 123 ± 20, CO 125 ± 26 W; after TR 148 ± 23 W, CO 127 ± 25 W; mean ± SD). Blood was taken at rest and after exercise to determine coagulation (e.g., aPTT, thrombin potential, TAT, F1+2, several coagulation factors) and fibrinolytic (e.g., tPA, PAI) parameters. The training intervention induced an elevation of physical capacity in TR by 17 % (rel. VO2max) that led to a statistical relevant prolongation of aPTT at rest. Although absolute power output during the second exercise test was 20 % higher in TR, we detected an attenuated exercise-induced decrease of aPTT and attenuated increase of F1+2 after training. Resting levels of tPA- and PAI-Ag decreased slightly but not significantly after training. Exercise-induced changes were comparable after training in spite of higher power output in TR. Although the effects are small in healthy men, training modifies exercise-induced blood coagulation positively. The fact that exercise-induced changes in blood coagulation and fibrinolysis are rather attenuated or unchanged in the training group, in spite of a 20 % higher absolute power output during exercise, substantiates the adjusting effect of endurance training and the importance of physical fitness in primary prevention.  相似文献   
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Recommendations concerning the management of hemoglobin levels and hematocrit in patients on extracorporeal membrane oxygenation (ECMO) still advise maintenance of a normal hematocrit. In contrast, current transfusion guidelines for critically ill patients support restrictive transfusion practice. We report on a series of patients receiving venovenous ECMO (vvECMO) for acute respiratory distress syndrome (ARDS) treated according to the restrictive transfusion regimen recommended for critically ill patients. We retrospectively analyzed 18 patients receiving vvECMO due to severe ARDS. Hemoglobin concentrations were kept between 7 and 9 g/dL with a transfusion trigger at 7 g/dL or when physiological transfusion triggers were apparent. We assessed baseline data, hospital mortality, time on ECMO, hemoglobin levels, hematocrit, quantities of packed red blood cells received, and lactate concentrations and compared survivors and nonsurvivors. The overall mortality of all patients on vvECMO was 38.9%. Mean hemoglobin concentration over all patients and ECMO days was 8.30 ± 0.51 g/dL, and hematocrit was 0.25 ± 0.01, with no difference between survivors and nonsurvivors. Mean numbers of given PRBCs showed a trend towards higher quantities in the group of nonsurvivors, but the difference was not significant (1.97 ± 1.47 vs. 0.96 ± 0.76 units; P = 0.07). Mean lactate clearance from the first to the third day was 45.4 ± 28.3%, with no significant difference between survivors and nonsurvivors (P = 0.19). In our cohort of patients treated with ECMO due to severe ARDS, the application of a restrictive transfusion protocol did not result in an increased mortality. Safety and feasibility of the application of a restrictive transfusion protocol in patients on ECMO must further be evaluated in randomized controlled trials.  相似文献   
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Udo -D. Matzke 《Der Internist》2000,5(6):M184-M185
Wahr ist, dass die Menschen umso gesünder sie sind, je wohlhabender das Land ist, in dem sie leben. Wenn es den Anschein hat, es gäbe heute mehr Kranke als früher, so liegt das an einem Paradox: Je ausgereifter die medizinische Versorgung wird, desto mehr Behandlungsbedürftige gibt es.  相似文献   
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An easy and efficient route to synthesize gel materials based on polymeric ionic liquids (PILs) is presented. The radical polymerization of imidazolium (Im)‐based ionic liquids (ILs) bearing a vinyl group ([VEIm][Br], [VEIm][Ac], [VBIm][Br], [VBIm][Cl]) with crosslinker (CL) N,N′‐methylenebisacrylamide (Bis) in water results in polyionic liquid hydrogels. Thermal and mechanical properties (tensile and compression tests) are investigated and compared with two different types of hydrogels. One is a polyacrylamide (PAAm) hydrogel having covalent‐type crosslinking. The other is an alginate‐based hydrogel having ionic‐type crosslinking. Prepared IL‐hydrogel materials provide favorable flexibility, adjustable by varying the CL ratio and water content. The higher the CL ratio is, the higher the fragility of the gel matrix. The gelation time of the hydrogels depends on the alkyl chain length, as well as the size of the anion.

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