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Background: The American College of Cardiology (ACC)/American Heart Association (AHA) guidelines for Perioperative Cardiovascular Evaluation for Noncardiac Surgery recommend an algorithm for a stepwise approach to preoperative cardiac assessment in vascular surgery patients. The authors' main objective was to determine adherence to the ACC/AHA guidelines on perioperative care in daily clinical practice.

Methods: Between May and December 2004, data on 711 consecutive peripheral vascular surgery patients were collected from 11 hospitals in The Netherlands. This survey was conducted within the infrastructure of the Euro Heart Survey Programme. The authors retrospectively applied the ACC/AHA guideline algorithm to each patient in their data set and subsequently compared observed clinical practice data with these recommendations.

Results: Although 185 of the total 711 patients (26%) fulfilled the ACC/AHA guideline criteria to recommend preoperative noninvasive cardiac testing, clinicians had performed testing in only 38 of those cases (21%). Conversely, of the 526 patients for whom noninvasive testing was not recommended, guidelines were followed in 467 patients (89%). Overall, patients who had not been tested, irrespective of guideline recommendation, received less cardioprotective medications, whereas patients who underwent noninvasive testing were significantly more often treated with cardiovascular drugs ([beta]-blockers 43% vs. 77%, statins 52% vs. 83%, platelet inhibitors 80% vs. 85%, respectively; all P < 0.05). Moreover, the authors did not observe significant differences in cardiovascular medical therapy between patients with a normal test result and patients with an abnormal test result.  相似文献   

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麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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A rural hospital elective in a diploma nursing program is described. A need and opportunity for this unique practicum was identified in a Canadian province where one-third of the acute care beds are in hospitals of under 100 beds, located primarily in towns outside of metropolitan areas. The six week course offers students 35 hours of classroom content focusing on rural health care concepts plus a 150 hour practicum in one of three participating hospitals. The course is seen as unique in that it focuses on rural health care and is offered within the context of a diploma nursing program. Vive student outcomes are identified: awareness of the differences between rural and urban health care; integration of knowledge and experience from previous nursing courses as it relates to the rural context; increasing understanding of how rural population groups affect health care delivery; awareness of rural employment opportunities; and, preparation for the graduate role. A shared vision and collaborative effort on the part of the School of Nursing, the rural hospitals and the host communities has been necessary to establish and maintain such a course.  相似文献   
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55Co and 57Co were produced via (p, α) and (p, 2p) reactions, respectively, on highly enriched 58Ni. Thin deposits of 58Ni on Cu backing, obtained electrolytically, were irradiated using a slanting beam. The separation of radiocobalt and the recovery of the enriched target material were effected via anion-exchange chromatography.  相似文献   
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Results are presented of a Phase III international multicentre trial to study the effect of a new low-dose oral contraceptive (OC) containing 20 micrograms ethinylestradiol and 150 micrograms desogestrel (Mercilon) regarding efficacy, cycle control, blood pressure, and acceptability. Altogether 1,684 women from 12 European countries were included in the study. Four pregnancies occurred, 3 of them patient failures, one tablet failure. The overall Pearl Index was 0.20. The frequency of irregular bleeding was comparable to that recorded with other commonly used low-dose OCs. No serious side effects occurred. The incidence of the most frequently reported subjective side effects--headache, nausea and breast tension--was already low after the first cycle of treatment and decreased to below pretreatment levels with continued use. There was a small increase in mean body weight, which was confined essentially to young women. The preparation did not affect the mean systolic or diastolic blood pressure. This new preparation has thus proved to be an effective, safe and well-accepted ultra low-dose oral contraceptive.  相似文献   
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To develop guidelines for clinical magnetic resonance imaging of the liver, the authors undertook an animal study to investigate the effect of dose and pulse sequence on liver signal intensity in gadopentetate dimeglumine—enhanced echo-planar imaging. Serial imaging of the liver was performed in anesthetized rats after intravenous administration of five different doses (0.01, 0.05, 0.1, 0.2, and 0.5 mmol/kg) of contrast agent, with six different pulse sequences. The results show that gadopentetate dimeglumine—enhanced echo-planar images obtained during the perfusion phase can yield either positive (due to increased T1 relaxation rates) or negative (due to susceptibility-induced increased T2 relaxation rates) liver enhancement depending on choice of pulse sequence and dose. At the current clinically recommended dose of 0.1 mmol/kg, maximal liver signal enhancement was seen with a T1-weighted inversion-recovery sequence, while maximal liver signal diminution was seen with a T2*-weighted gradient-echo sequence. The authors conclude that gadopentetate dimeglumine—enhanced echo-planar imaging can provide T1, T2, and T2* contrast that may be exploited for both lesion detection and lesion characterization.  相似文献   
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In patients with liver cirrhosis a transjugularly placed intrahepatic portocaval shunt (TIPS) is a non-surgical portosystemic device which aims to reduce portal venons pressure. In comparison with Doppler sonography, we evaluated in 28 patients the diagnostic impact of liver perfusion scintigraphy (with technetium-99m diethylene triamine penta-acetic acid) in the assessment of changes in the hepatic blood flow after TIPS shunting. The arterial and portal contributions to hepatic flow were calculated from the areas under the biphasic timeactivity curve. In the course of TIPS shunting, patency is threatened by reocclusion. Angiography is the gold standard for TIPS shunt reassessment. However, there is a need for a less invasive diagnostic procedure, such as scintigraphy or Doppler sonography, for the early detection of shunt insufficiency. Scintigraphy demonstrated that prior to TIPS shunting the portal venons contribution to hepatic perfusion was reduced to 29.2%, this reduction being due to portal hypertension. After TIPS placement a significant increase in portal venous perfusion was observed (38.2%;P<0.02). TIPS shunt occlusion was identified in patients by a significant reduction in the scintigraphically measured portal venons contribution to hepatic blood flow. Hepatic perfusion scintigraphy appears to be a valuable method to determine the immediate effect of TIPS on hepatic blood flow. Post-TIPS follow-up studies of hepatic haemodynamics by liver perfusion scintigraphy appear able to contribute to the detection of TIPS shunt occlusion before the clinical consequences of this complication have become apparent.  相似文献   
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