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排序方式: 共有7694条查询结果,搜索用时 15 毫秒
71.
目的:介绍新的更有效的内痔注射方式。方法:用多普勒血流仪引导注射治疗内痔出血与脱出,与单纯注射治疗对照观察。结果:一年后出血复发率治疗组为10%,对照组为119.17%(P〈0.05);内痔脱出复发率治疗组为18.25%,对照组为25%。结论:用多普勒血流仪引导注射治疗内痔能更有效的闭塞痔动脉。 相似文献
72.
慢性光化性皮炎的病因诊断及治疗 总被引:1,自引:1,他引:0
目的;探讨慢性光化性皮炎(CAD)的病因,诊断及治疗,方法:查阅文献,对引起CAD的光敏物、发病机理及治疗进行分析,结果:约11%的CAD患者有光敏物接触史;62%光敏性隐匿;27%有慢性皮炎病史;结论:CAD发病与光变态反应有关,避光治疗有效。 相似文献
73.
The market for pharmacoeconomic analysis is rapidly expanding. Demand for experienced investigators seems to have outpaced the capacity of both the academic community and industry to train qualified practitioners. The result is that many professionals charged with producing and using cost-effectiveness and other drug-related economic evaluation studies may lack the basic skills required to carry out their duties. This, in turn, raises concerns regarding the credibility and integrity of the field as a whole. In our opinion, the adoption of self-imposed practice guidelines is a necessary first step in confronting these issues. However, the power of guidelines to promote responsible practice will be limited by the technical preparation of the analysts charged with adhering to them. A long term solution requires a collaborative commitment, on the part of both the academic community and the private sector, to targeted graduate training in pharmacoeconomic methods, and to the provision of ample opportunities for continuing professional education. 相似文献
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J T Winterer S Lehnhardt B Schneider K Neumann K H Allmann J Laubenberger M Langer 《Investigative radiology》1999,34(8):516-522
RATIONALE AND OBJECTIVES: A large variety of cardiac MRI sequences have been introduced for heart morphology evaluation. The aim of this study was to establish a practicable and robust examination protocol for standard high-field systems applying nongradient echo sequences with single- and multi-slice acquisition. METHODS: Fifty-one patients received electrocardiogramgated MRI of the heart with "black-blood" preparation, comparing three single-slice and three multislice sequences with a T1-weighted turbo spin echo reference sequence. Demarcation of the left ventricular myocardium and cavity and the extent of flow and motion artifacts were assessed. RESULTS: The myocardium and left ventricular cavity were depicted best with the single-slice T1- and T2-weighted turbo spin echo sequence. The nonbreath-hold multislice sequences produced marked artifacts and therefore were of poor diagnostic value. The TIRM haste sequence was best suited for fat suppression. The T2-weighted breath-hold single-shot sequence with half-Fourier imaging proved to be most appropriate for multislice imaging. CONCLUSIONS: Sufficient depiction of heart morphology with comprehensive evaluation of signal changes can be achieved using nongradient spin echo and turbo spin echo sequences with breath-holding. For rational imaging of myocardial and heart chamber morphology, multislice and single-slice sequences should be combined. 相似文献
76.
Positive end-expiratory pressure prevents atelectasis during general anaesthesia even in the presence of a high inspired oxygen concentration 总被引:2,自引:0,他引:2
Neumann P Rothen HU Berglund JE Valtysson J Magnusson A Hedenstierna G 《Acta anaesthesiologica Scandinavica》1999,43(3):295-301
BACKGROUND: General anaesthesia impairs the gas exchange in the lungs, and moderate desaturation (SaO2 86-90%) occurred in 50% of anaesthetised patients in a blinded pulse oximetry study. A high FiO2 might reduce the risk of hypoxaemia, but can also promote atelectasis. We hypothesised that a moderate positive end-expiratory pressure (PEEP) level of 10 cmH2O can prevent atelectasis during ventilation with an FiO2 = 1.0. METHODS: Atelectasis was evaluated by computed tomography (CT) in 13 ASA I-II patients undergoing elective surgery. CT scans were obtained before and 15 min after induction of anaesthesia. Then, recruitment of collapsed lung tissue was performed as a "vital capacity manoeuvre" (VCM, inspiration with Paw = 40 cmH2O for 15 s), and a CT scan was obtained at the end of the VCM. Thereafter, PEEP = 0 cmH2O was applied in group 1, and PEEP = 10 cmH2O in group 2. Additional CT scans were obtained after the VCM. Oxygenation was measured before and after the VCM. RESULTS: Atelectasis (> 1 cm2) was present in 12 of the 13 patients after induction of anaesthesia. At 5 and 10 min after the VCM, atelectasis was significantly smaller in group 2 than group 1 (P < 0.005). A significant inverse correlation was found between PaO2 and atelectasis. CONCLUSIONS: PEEP = 10 cmH2O reduced atelectasis formation after a VCM, when FiO2 = 1.0 was used. Thus, a VCM followed by PEEP = 10 cmH2O should be considered when patients are ventilated with a high FiO2 and gas exchange is impaired. 相似文献
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