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21.
Influence of Electromagnetic Fields on Function of Automated External Defibrillators 总被引:3,自引:2,他引:1
Roman Fleischhackl MD Florian Singer MD Wolfgang Nitsche PhD MSc Eng Guenther Gamperl MSc Engineering Bernhard Roessler MD Jasmin Arrich MD Sabine Fleischhackl MD Heidrun Losert MD Fritz Sterz MD Martina Mittlboeck PhD MSc Klaus Hoerauf PhD MD 《Academic emergency medicine》2006,13(1):1-6
Objectives: In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false‐positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus. Methods: Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence‐randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure. Results: Of 760 tests run, 18 (2.37%) cases of false‐positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields. Conclusions: AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed. 相似文献
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Sami R Achem MD Alexander Klaus MD Ronald A Hinder MD PhD Kenneth R DeVault MD 《The American journal of medicine》2004,116(10):717-718
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Albert B. Zajko M.D. Klaus M. Bron William L. Campbell 《Cardiovascular and interventional radiology》1987,10(1):28-31
Biliary obstruction and multiple hepatic abscesses occurred in a patient after ligation of a segmental branch of the right
hepatic duct. The patient was successfully managed by transhepatic biliary drainage and balloon dilatation of an internal
fistula that developed between the ligated duct and a Roux limb of jejunum. Internal biliary fistulas may be dilated using
interventioanl radiologic techniques to permit nonobstructed bile flow. Implications for the nonsurgical treatment' of biliary
strictures are discussed. 相似文献
24.
Asymmetric Electrophilic α-Amidoalkylation, 4): Generation and Trapping Reactions of Chiral N- Acylpyrrolidiniumions The pyrrole derivatives 1 , 6 , and 10 react in the presence of TiCl4 with the silyl enol ether 3 to form α-substituted pyrrolidine amides steroselectively. 6 and 10 (after HCl-addition = > 11 ) react even at ?78°C, the reaction of 10 exceeds that of 6 in yield and stereoselectivity. 相似文献
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Dr Klaus Rieneck 《European journal of haematology》2006,76(5):451-452
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Benyam Asefa Paul Kauler Denis Cournoyer Shirley Lehnert T. Y.-K. Chow 《Current genetics》1998,34(5):360-367
The deoxyribonucleases (DNases) have been shown genetically to be important in the vital processes of DNA repair and recombination.
The NUD1 gene, which codes for an endo-exonuclease of Saccharomyces cerevisiae, was analyzed for its role in the DNA double-strand break (DSB) repair processes. While the nud1 strain is only slightly sensitive to ionizing radiation, expression of the HO-endonuclease to introduce a DSB at the MAT locus in that strain results in cell death. Cell survival is inversely proportional to the duration of HO-endonuclease expression.
Analysis of the surviving colonies from the nud1 strain indicated that many of the survivors are sterile and that the proportion of these sterile survivors increases with
the time of HO-endonuclease expression. On the other hand, the surviving colonies from the isogenic NUD1 strain are mating-proficient. Interestingly, double mutants of nud1 rad52 are more resistant to ionizing irradiation than the rad52 strain and have a cell-survival fraction of 32% for rad52-1 nud1 and 9% for rad52::URA3 nud1 following prolonged HO-endonuclease expression, indicating that nud1 has a suppressor effect on the DSB-induced lethality in rad52. Polymerase chain reaction analysis showed that many of the nud1 survivors contained small alterations within the MAT locus, suggesting that the survivors arose through the process of non-homologous end-joining. These results suggest that
the endo-exonuclease acts at a DSB to promote DNA repair via the homologous recombination pathway.
Received: 20 July / 20 September 1998 相似文献
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