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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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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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The mechanism of hyperlipidaemia in the nephrotic syndrome has not been fully established. We propose that it results from hypoalbuminaemia due to inhibition of the reaction catalysed by lecithin cholesterol acyltransferase converting cholesterol of high density lipoproteins to cholesterol esters and to an inhibition of high density lipoprotein particle formation from very low density lipoproteins due to reduced activity of lipoprotein lipase. 相似文献
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B. J. Nickoloff R. S. Mitra B. L. Riser V. M. Dixit J. Varani 《The American journal of pathology》1988,132(3):543-551
Normal human epidermal keratinocytes (KC) grown under conditions that maintain the undifferentiated state are highly motile. Migration of these cells as measured in two different assays (migration out of an agarose drop explant, and into micropore filters in a modified Boyden chamber), is stimulated by fibronectin (FN) and to a lesser extent by thrombospondin (TSP). In contrast, laminin (LN) inhibits KC migration. Cultivation of the cells for 1 day under conditions that induce differentiation (ie, in the presence of 1.4 mM Ca2+) suppresses KC motility. A number of soluble growth modulating polypeptide factors also influence KC migration. Transforming growth factor-beta (TGF-beta) and epidermal growth factor (EGF) stimulate KC motility. These factors simultaneously induce KC production of FN and a significant portion of the stimulated motility can be inhibited with antibodies to FN. EGF and somatomedin-C (SM-C), but not TGF-beta, also stimulate TSP production while EGF and SM-C (but not TGF-beta) induce KC proliferation. In contrast to these factors, interferon-gamma (INF-gamma) inhibits KC production of both FN and TSP and concomitantly inhibits both motility and proliferation. These data suggest that KC properties essential for normal wound healing (ie, motility and proliferation) are regulated by both extracellular matrix molecules and soluble peptide factors. Finally, these effects of various growth promoting and antiproliferative factors on KCs may, in part, be mediated through alteration in the endogenous production of extracellular matrix molecules by KCs. 相似文献
8.
Lina?Hu Vishwa?Deep?Dixit Valeria?de Mello-Coelho Dennis?D?TaubEmail author 《BMC immunology》2004,5(1):15
Background
The CXCL1 chemokines, macrophage inflammatory protein-2 (MIP-2) and cytokine-induced neutrophil chemoattractant (KC), have been shown to play a role in a number of pathophysiological disease states including endotoxin-induced inflammation and bacterial meningitis. While the expression of these chemokines has been identified in a variety of cell types in the mouse, little is known about their expression with murine B-lymphocytes. 相似文献9.
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Volumetric air sampling was performed near Corpus Christi, Texas during 1988 and supplemented with data from 1987 and 1989. Frequencies of captured pollen grains of Parthenium hysterophorus, Ambrosia and allied genera, Helianthus, and other Asteracea were examined. Asteraceous aerospora in 1988 accounted for 22.1% of all pollen found, of which 83.4% were pollen of Ambrosia, 12.4% of Parthenium, and the remainder (4.1%) representative of other genera. Capture of native Ambrosia species and P. hysterophorus peaked in September and October in 1987 and 1988, but Parthenium pollen was also found year round with a smaller secondary peak during May, 1988 and 1989. In the winter a different Ambrosia pollen was captured which compared with A. hispida found in the Yucatan Peninsula and southern Florida at a time when no ragweed was flowering in the vicinity of Corpus Christi. Such a pollen capture probably represents long distance dispersal (ca. 600 miles, 965 km) on strong easterly to southerly prevailing winds. Pollen capture occurred most frequently during daylight hours when percent relative humidity was lower and near midnight when inversions occur. Comparison of pollen capture with meteorologic data demonstrated that photoperiodic responses probably account for the initiation and termination of Ambrosia flowering, and to some extent that of Parthenium, and not sharply lowered temperatures or frost for ending pollen release. Previous plant surveys have shown that P. hysterophorus is more common in the Corpus Christi area than species of Ambrosia, or any other Asteraceae, even though ragweed pollen capture proved 6.9 times greater. This disparity is most likely due to limited long distance dispersal of Parthenium pollen, less pollen produced per another, and a less developed mechanism of wind pollination (passive dispersal or amphiphilous). Since both Parthenium and Ambrosia are significant allergenic plants, correlations between airborne pollen of Parthenium and allergic potential suggest that a prolonged pollination season and perhaps increased allergenicity of unique Parthenium pollen proteins allow Parthenium to be a major allergen despite significantly less ambient pollen. 相似文献