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61.
J. G. BLIGH 《Medical education》1992,26(6):497-502
Self-directed learning is a natural way for adults to learn. Vocational training for general practice is a preparation for unsupervised clinical work that will be supported, in the main, by continuing medical education. This study uses the Self-Directed Learning Readiness Scale to investigate factors influencing readiness for such learning among a sample of general practice trainees. Three principal factors emerged from analysis: enjoyment and enthusiasm for learning; a positive self-concept as a learner and a factor suggesting the possibility of a 'reproducing' orientation to learning. These factors may reflect approaches to learning in general rather than these adopted for professional learning, but offer helpful pointers for the development of both vocational training and of continuing medical education. 相似文献
62.
Camilla Nyboe Jonas A. Funder Morten H. Smerup Hans Nygaard J. Michael Hasenkam 《European journal of cardio-thoracic surgery》2006,29(6):1008-1013
Objective: Mechanical heart valves can cause thromboembolic complications, possibly due to abnormal flow patterns that produce turbulence downstream of the valve. The objective of this study was to investigate whether three different bileaflet valve designs would exhibit clinically relevant differences in downstream turbulent stresses. Methods: Three bileaflet mechanical heart valves (Medtronic Advantage®, CarboMedics© Orbis™ Universal and St. Jude Medical® Standard) were implanted into 19 female 90 kg pigs. Blood velocity was measured during open chest conditions in the cross sectional area downstream of the valves with 10 MHz ultrasonic probes connected to a modified Alfred® Pulsed Doppler equipment. As a measure of turbulence, Reynolds normal stress (RNS) was calculated at three different cardiac output ranges (3–4, 4.5–5.5, 6–7 L/min). Results: Data from 12 animals were obtained. RNS correlated with increasing cardiac outputs. The highest instantaneous RNS observed in these experiments was 47 N/m2, and the mean RNS taken spatially over the cross sectional area of the aorta during systole was between 3 N/m2 and 15 N/m2. In none of the cardiac output ranges RNS values exceeded the lower critical limit for erythrocyte or thrombocyte damage for any of the valve designs. Conclusions: Reynolds normal stress values were below 100 N/m2 for all three valve designs and the difference in design was not reflected in generation of turbulence. Hence, it is unlikely that any of the valve designs causes flow induced damage to platelets or erythrocytes. 相似文献
63.
红细胞膜通道力学效应的探讨 总被引:1,自引:0,他引:1
萧天庆 《中国生物医学工程学报》1992,11(3):150-156
在考察红细胞双凹碟形体形成的基础上,讨论了红细胞的输氧功能与红细胞变形的关系,揭示了红细胞膜通道的力学效应:当红细胞呈双凹碟形时,PiPo的地方,红细胞膜通道有释放出氧的现象,其氧的总流率为 J=Lo_2(Pio_2-Poo_2) Lp(Pi-Po) 式中Lo_2为O_2分压差引起的膜通道对氧的流导,PiO_2、Poo_2为膜内外的氧分压;Lp为由于压差引起的膜通道对氧的流导。 相似文献
64.
65.
1.5T超导磁共振制冷系统的工作原理及日常维护 总被引:1,自引:0,他引:1
介绍GE 1.5T超导磁共振制冷系统的组成和工作原理,讨论日常维护的要点及其必要性。 相似文献
66.
An operating theatre fire and the steps taken to deal with it are described; the difficulties encountered in evacuating anaesthetised patients are highlighted. Measures which might be taken to prevent recurrence of these problems, and recommendations on the institution of fire drills for the safety of patients and staff are given. 相似文献
67.
68.
从机械和电路两方面分析了 KLHZ-001型后装机出源阻力大的原因 ,并分别阐述了维修办法. 相似文献
69.
Louise Rose MN Adult Ed Cert BN ICU Cert Dip Nurs Marie F. Gerdtz RN BN AE Cert GDAET PhD 《Australasian emergency nursing journal : AENJ》2007,10(1):26-29
The use of mechanical ventilation in the Emergency Department requires adequate resources in order to maintain patient safety and avoid potential risks. Moreover, developments in technology require increased knowledge of mechanical ventilation techniques to address the complexity of decision-making involved. Organisational issues and system factors have the potential to negatively impact on the ability of the emergency service to provide optimum care to patients receiving mechanical ventilation. These issues include staffing and skill-mix, demand on emergency services, role-delineation, scope of practice, and current mechanisms for monitoring of quality and safety. Furthermore, in response to advances in ventilator technology, current education programs for both nursing and medical staff require review to ensure that they provide comprehensive information about the types of ventilation techniques now available and the relative risks and benefits associated with their application.This article is the second in a two-part series and explores the educational and organisational factors that impact upon safety and quality of care delivered to patients receiving mechanical ventilation in the emergency department. Recommendations for future policy development, curriculum review and reporting mechanisms to support further research in the application of mechanical ventilation in the emergency department are made. 相似文献
70.
H. W. Waclawiczek 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1987,370(1):37-52
Zusammenfassung Von 1972 bis 1983 wurden 351 Patienten wegen eines mechanischen Dünndarm- (n = 256) bzw. Dickdarmileus (n = 95) operiert. Die chirurgische Komplikationsrate betrug beim Dünndarmverschluß 28,1 bzw. beim Dickdarmileus 24,3%, wobei am häufigsten Anastomosendehiscen-zen nach Resektionen (17,7% bzw. 53,8%), Enterotomien (5,8%/27,2%), Platzbäuche (3,5%/4,2%) und ein Re-Ileus (5,5%/3,2%) vorlagen. Die internistischen Komplikationen (postop. Pneumonien, Lungenembolien, kardiale Dekompensationen etc.) betrugen 17,9% bzw. 22,1 %. Die perioperative Letalität lag beim Dünndarmileus bei 20,6% und beim Dickdarmileus bei 33,4%. Als Schlußfolgerungen dieser retrospektiven Analyse ergaben sich die frühzeitige, perioperative, intensiv-medizinische Behandlung, die generelle Thrombose-, Pneumonie- und StreBulcusprophylaxe, die exakte, präoperative Röntgendiagnostik, die strenge Indikationsstellung für Enterotomien und Resektionen, das dreizeitige Vorgehen beim linksseitigen Dickdarmileus, die Inkontinuitätsresektion nach Hartmann bei entzündlichen Prozessen im Sigmabereich und die innere Dünndarmschienung bei Peritonitis bzw. ausgedehnten Adhäsionen. Dadurch konnte seit Anfang 1984 die Komplikationsbzw. Letalitätsrate beim Dünndarmileus (n = 64) auf 9,4% bzw. 4,7% und beim Dickdarmileus (n = 20) auf 10% bzw. 5% gesenkt werden.
Experiences with operations of mechanical ileus
Summary Between 1972 and 1983 a total of 351 patients was operated suffering from mechanical occlusion of the small intestine (n = 256) and of the colon (n = 95). The surgical complication rate amounted to 28.1% in cases of small intestine ileus and to 24.3% in cases of colon ileus; the most frequent complications were anastomotic dehiscences following resections (small intestine 17.7%/colon 33.8%), enterotomies (5.8%/27.2%), abdominal wall ruptures (3.5%/4.2%) and re-ileus (5.5%/3.2%). The medical complication rate (postop. pneumonia, pulmonary embolism, cardial decompensation etc.) amounted to 17.7% resp. 22.1%. All these complications carried a mortality of 20.6% in small intestine ileus and of 30.4% in colon ileus. The consequences of this retrospective analysis resulted in: early intensive care treatment, general perioperative thrombosis-, pneumonia- and stress ulcer prophylaxis, exact preoperative radiological diagnosis, strict indications for enterotomies and resections, sole transversostomy in stage of ileus for the left-sided colon obstruction caused by carcinoma, discontinuity resection by Hartmann in cases of inflammatory or perforated large bowel stenoses and tube decompression of the small bowel in cases of peritonitis or wide-spread adhesions. Since 1984 we could prospectively decrease the complication resp. mortality rate of the small intestine ileus (n = 64) to 9.4% resp. 4.7% and of the colon ileus (n = 20) to 10% resp. 5%.相似文献