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排序方式: 共有510条查询结果,搜索用时 10 毫秒
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Farshad Abir Iannis Kakisis Bauer Sumpio 《European journal of vascular and endovascular surgery》2003,25(2):110-117
OBJECTIVES: to outline the appropriate pre-operative cardiac work-up for patients who are scheduled for major peripheral vascular surgery. DESIGN: review of the literature. MATERIALS AND METHODS: a review of the literature focusing on studies that have correlated the pre-operative cardiac work-up patients receive to the cardiac morbidity and mortality following vascular surgery. Only studies with level A evidence were included. RESULTS: peri-operative beta blockade has been shown to decrease cardiac complications after vascular surgery in all risk groups. Non-invasive cardiac testing is only necessary for patients in the intermediate/high risk group. Coronary revascularization should only be considered after a positive non-invasive cardiac test. CONCLUSIONS: patients must be risk stratified pre-operatively based on history and physical examination. Low risk patients should receive peri-operative beta blockade only with no further non-invasive testing. On the other hand, intermediate and high risk patients should undergo non-invasive cardiac testing before going to the operating room. 相似文献
3.
The purpose of this study was to assess the role of cyclic deformation in modulating the production by endothelial cells (ECs) in culture of a recently described endothelium-derived smooth muscle cell contracting factor, endothelin. We grew bovine aortic ECs to confluence on culture plates with flexible membrane bottoms. Vacuum (-20 kPa) was applied to deform the membrane to 24% strain at 60 cycles/min for 1, 3, or 5 days. Control ECs were grown on the same membrane but without vacuum deformation. The conditioned media were collected, centrifuged at 10,000 rpm for 10 minutes to remove cells and debris, and the supernatant fluid was subjected to radioimmunoassay for endothelin. The results demonstrate that bovine aortic ECs release a basal level of endothelin under stationary conditions (107.1 +/- 14.7 pg/10(5) cells), and this production increased fivefold to sixfold with cyclic stretch. Thus physical forces exerted on ECs in culture can influence the secretion of this vasoconstrictive molecule. 相似文献
4.
Sequential contrast-enhanced MR imaging of the penis 总被引:1,自引:0,他引:1
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Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan 总被引:2,自引:0,他引:2
B Herrmann MAM Salih BE Yousif O Abdelwahab P-A Mårdh 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(2):169-172
The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of ≥1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies. 相似文献
7.
P. VON DEN DRIESCH C. STEFFAN A. ZÖBE O.P. HORNSTEIN 《Clinical and experimental dermatology》1994,19(3):274-277
We report the case of a 39-year-old female patient suffering from Sweet's syndrome after an upper respiratory tract infection. Cyclosporin A at a dose of 10 mg/kg per day was given as initial treatment. Skin lesions and general malaise resolved within 9 days. The cyclosporin dose was decreased within 21 days, without recurrence of the eruption. Cyclosporin is a potent inhibitor of T lymphocytes, but affects granulocyte and monocyte functions as well. Success of treatment in our case shows that cyclosporin represents an alternative to steroid treatment in patients with Sweet's syndrome. 相似文献
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9.
J. D. Kakisis F. Abir C. D. Liapis B. E. Sumpio 《European journal of vascular and endovascular surgery》2003,25(6):493-504
OBJECTIVES: to summarize existing evidence regarding the benefits and the risks of all available interventional and medical means aimed at cardiac risk reduction in patients undergoing vascular surgery. DESIGN: review of the literature. MATERIALS AND METHODS: a critical review of all studies examining the impact of various prophylactic cardiac maneuvers on perioperative outcome following vascular surgery was performed. Overall mortality, cardiac mortality and myocardial infarction rate were used as the outcome measures. RESULTS: coronary artery bypass grafting is associated with a 60% decrease in perioperative mortality in patients undergoing vascular surgery, but in most of the cases this decrease does not outweigh the combined risk of the cardiac and the subsequent noncardiac vascular procedure. Data supporting the cardioprotective effect of percutaneous transluminal angioplasty in the perioperative setting are insufficient. beta-blockade has been shown to decrease perioperative mortality and cardiac morbidity in both high-risk (strong evidence) and low-risk (weak evidence) patients. CONCLUSIONS: coronary revascularization is rarely indicated to simply get the patient through vascular surgery and should be reserved for patients who would need it irrespective of the scheduled vascular procedure. Among all available pharmacological agents, including beta-blockers, alpha-agonists, calcium channel blockers and nitrates, only beta-blockers have been proven to reduce the cardiac risk of vascular surgery. 相似文献
10.
Dynamic particle image velocimetry (PIV) was applied to the study of the flow field associated with prosthetic heart valves.
The results were compared with those of laser Doppler anemometry (LDA). Anatomically and antianatomically oriented Jyros (JR)
and St. Jude Medical (SJM) valves were compared in the mitral position to study the effects of valve design on the downstream
flow field. The experimental program used a dynamic PIV system utilizing high-speed, high-resolution video to map the true
time-resolved velocity field inside the simulated ventricle. This system was complemented by a study using the more traditional
LDA system for comparison. Based on the experimental data, the following general conclusions can be made. High-resolution
dynamic PIV can capture true chronological changes in the velocity and turbulence fields. It also produces very detailed velocity
and turbulence information comparable to the LDA results. In the vertical measuring plane that passes both the center of the
aortic and mitral valves (A-A section), the two valves (the SJM and the JR) show distinct circulatory flow patterns when the
valve is installed in the antianatomical orientation. Small differences in valve design can generate noticeable differences,
particularly during the accelerating flow phase. The SJM valve maintains a relatively high velocity through the central orifice;
the curved leaflets of the JR valve generate higher velocities with a divergent flow during the accelerating and peak flow
phases. In the velocity field directly below the mitral valve and normal to the previous measuring plane (B-B section), where
characteristic differences in valve design will be visible, symmetrical twin circulations were observed because of the divergent
nature of the flow generated by the two inclined half-disks installed in the antianatomical orientation. The SJM valve, with
a central downward flow near the valve, is contrasted with the JR valve, which has a peripheral downward circulation with
higher, turbulent stresses. 相似文献