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Background : It is well known that reoperation for recurrent coronary artery disease is more difficult than primary coronary artery bypass grafting. However, it is possible to reduce the morbidity and mortality of reoperation to the same level as the initial procedure with careful surgical technique. Methods : A retrospective study of the first 200 patients who underwent redo coronary bypass grafting was undertaken. Results : In the first 200 cases of redo coronary bypass grafting at St George Hospital, Sydney (August 1986–January 1995), there were five in-hospital deaths (2.5%). There was one case of sternal infection (0.5%), which required surgical debridement, three cases of stroke (1.5%), one case of postoperative bleeding (0.5%), which required a return to theatre and six cases (3%) required mechanical ventilation for more than 24h. The need for major postoperative support (such as intra-aortic balloon pumping/adrenaline infusion) was significantly affected by the degree of urgency and the degree of pre-operative ventricular impairment. Conclusions : The mortality rate of redo coronary artery bypass grafting in this series is similar to that of primary surgery described in other reports. 相似文献
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An ankylosed tooth can be suitable for obtaining orthodontic anchorage. However, if such a tooth lacks adequate clinical crown height, the anchorage will not be effective. In those situations surgical luxation or restorative crown augmentation is suggested. This case report is about the restorative treatment of an ankylosed, infraoccluded tooth to enhance the anchorage for forced orthodontic eruption of impacted maxillary canines. A crown augmentation in the form of a modified bilayered (sandwich) restoration using GIC, Composite resin and Silver amalgam on left maxillary first molar (26) was successful in sustaining the anchorage for forced eruption and alignment of impacted canines. 相似文献
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Jaishankar Raman Anand Dixit Gil Bolotin Valluvan Jeevanandam 《European journal of cardio-thoracic surgery》2006,30(2):347-352
BACKGROUND: Complex ventricular reconstruction (CVR) is now being employed increasingly thanks to the pioneering work of Dor. However, little is known about the failure mode of CVR. We present experience from three centres with CVR and an analysis of the failure modes. METHODS: Between January 1997 and February 2005, 284 patients underwent CVR in three centres in Australia and USA. All of the procedures were performed as adjuncts to coronary artery surgery and/or valvular surgery. Patients were followed-up clinically and/or echocardiographically. Failure modes were classified as fatal or non-fatal. Non-fatal failure mode (NFM) was defined as either persistent heart failure, recurrence of LV scar, need for ventricular assistance, persistent ventricular arrhythmia, or a combination. RESULTS: Operative mortality rate (OMR) was 8% (23 deaths). This fatal failure mode was most related to urgency of surgery and cardiogenic shock in 15 patients (5.3% of OMR), stroke in 5 patients (1.8%) or postoperative bi-ventricular failure (1%). Non-fatal failure modes accounted for morbidity in 26 patients (9%). This was predominantly due to persistent septal dyskinesis in 7 patients (2.46%), persistent mitral regurgitation in 5 (1.8%), postoperative ventricular tachycardia in 4 (1.4%), sub-optimal myocardial protection in 4 (1.4%) use of a large, stiff patch in 4 (1.4%). One hundred and ninety-nine of the surviving 261 patients (76%) were in NYHA Class I. CONCLUSIONS: Complex ventricular reconstruction is a robust technique that has lasting benefit. Failure modes have been identified and could be minimized by appropriate patient and procedure selection. 相似文献
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The effect of chemical shift on magnetic resonance (MR) imaging of the pituitary fossa was studied. Healthy volunteers underwent conventional MR imaging of the pituitary fossa and then imaging with the frequency-encoding gradient reversed or with the phase- and frequency-encoding gradients interchanged. Comparison of the image pairs in each subject showed that the thin, black stripe evident at the water-fat interface within the pituitary fossa was altered when the gradients were changed. Therefore, the low-intensity signal within the pituitary fossa is a chemical shift misregistration effect. 相似文献
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Two atmospheric isolates of Epicoccum nigrum (EN) were grown under sporulation conditions. Dialyzed extracts of spores, (greater than 95% pure) and pure mycelia were used for skin testing, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunoblotting. By skin testing, 49 of the 126 atopic patients were found to be sensitive to EN in St. Louis, Mo., and Corpus Christi, Texas, combined. On immunoblotting, which was performed on 17 sera, 44 bands (12.3 to 119.0 kd) were detected; six were unique to spore, four were unique to mycelium, and 34 were common to both. No single band bound IgE from all sera. The most frequent band corresponding to 42 kd occurred in 11 sera. Five other bands were recognized by more than one half, whereas the remainder bound fewer sera. All skin test-positive patients had positive immunoblots; the number of bands recognized varied from three to 25. Spore or mycelium-specific, as well as common bands were recognized by 13 of 17 sera. Two sera recognized only spore and mycelium-specific bands. Only spore-specific bands were bound by two sera. No strain differences were detected. The binding patterns were comparable in the sera from both St. Louis, Mo., and Corpus Christi, Texas. These data suggest that EN is a significant allergen in urban communities. Allergenic proteins occur in both spore and mycelium, suggesting that both must be included in the reagents for skin testing and immunotherapy. 相似文献
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Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
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