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Endoluminal revascularizaion of left main coronary artery vessels is considered to be relatively contraindicated because of a high procedural mortality and restenosis rate. This report describes the first successful case of endovascular stenting in an unprotected left main coronary artery stenosis in a heart transplant patient. 相似文献
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HC Thomas MW Lamé SK Dunston HJ Segall DW Wilson 《Canadian Metallurgical Quarterly》1998,151(2):236-244
Eosinophilic myocarditis followed by fibrosis of the cardiac muscle was observed in addition to peripheral blood eosinophilia in CBA/J mice infected with Toxocara canis. The infected mice were used as an experimental model of eosinophilic endomyocarditis associated with hypereosinophilic syndrome. Effects of in vivo treatment with MoAbs to adhesion molecules on eosinophilic myocarditis were examined using this experimental model. Expressions of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells of capillaries in myocardium were increased 1 and 2 weeks after infection. Infiltration of very late antigen (VLA)-4+ and/or CD11a+ cells into the cardiac muscles was also observed 1 and 2 weeks after infection. Infiltration of eosinophils into the heart was significantly suppressed by anti-CD18 MoAb and anti-VLA-4 MoAb, and focal fibrosis of the cardiac muscle was also significantly suppressed by combined administration of anti-CD18 and anti-ICAM-1 MoAbs. These results indicate that adhesion molecules may play important roles in eosinophilic myocarditis, and that blockade of interaction between adhesion molecules and their ligands may help to control it. 相似文献
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GS Ashcroft MA Horan SE Herrick RW Tarnuzzer GS Schultz MW Ferguson 《Canadian Metallurgical Quarterly》1997,290(3):581-591
Despite the association of increasing age with chronic wound-healing disorders and an impaired rate of healing of acute cutaneous wounds, the role of matrix metalloproteinases (MMPs) is unknown. To determine the spatial and temporal patterns and activities of MMP-1, -2, -3 and -9, 132 healthy humans aged between 19 and 96 years underwent 4-mm punch biopsies followed by wound excision between day 1 and day 180 post-wounding. Wounds showed an age-related increase in MMP-2 and MMP-9 immunostaining from day 3; this was associated with degradation of gelatin as shown by zymograms and with increased proteinase activity as shown by azocoll assays. Distinct spatial localisations for each MMP were observed: MMP-2 was found in epidermal structures; MMP-9 was observed in inflammatory cells up to day 21; MMP-1 was localised to keratinocytes at the wound margin. Normal old skin showed pro-MMP-2 bands on zymography and increased MMP-2 immunostaining. These results indicate that: (1) intrinsic ageing is associated with the up-regulation of MMPs previously associated with chronic wound healing; (2) wound-tissue proteinases are essentially active up to day 21 postwounding; and (3) intrinsic ageing may predispose to tissue breakdown disorders because of MMP-2 up-regulation in normal skin. 相似文献
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Systemic corticosteroid therapy is an established adjunct to beta-adrenergic medications in acute exacerbations of asthma. To date, no study has defined the role of long-acting intramuscular preparations of corticosteroids in pediatric patients with asthma. A pilot study was conducted to prospectively compare symptomatic improvement following a single injection of intramuscular dexamethasone (IMD) to a 3-day regimen of oral prednisone (OP) for children with mild to moderate wheezing episodes that are responsive to nebulized medications in the Pediatric Emergency Department (PED). The following children presenting with acute exacerbations of asthma to the PED were eligible for enrollment: age 3-16 years; more than two prior wheezing episodes; mild to moderate wheezing; and oxygen saturation 95% or more in room air. The study patients were randomly assigned to receive either IMD (n = 21) or OP (n = 21) in addition to a standardized treatment regimen of nebulized albuterol. All of the children were clinically rated for wheezing severity by the Pulmonary Index (PI) score at regular intervals during the study. Discharge home was based on clinical improvement during treatment in the PED; patients who were admitted to the hospital were removed from the study. Follow-up was conducted the fifth day after discharge from the ED either by clinic visit or by telephone. Patients were assessed for symptomatic improvement and relapse or clinical deterioration during the study period by a clinician blinded to group assignment. Forty-two children participated in this pilot study. There were no significant differences between the IMD and OP groups for gender or age. Mean ages were: 82 months (SD 46 months), IMD group; 63 months (SD 36 months), OP group. Clinical progress (based on PI) with treatment in the PED was the same in both groups: pretreatment median, PI = 6; PED discharge median, PI = 2. None of the study patients were hospitalized during the follow-up period, and all reported symptomatic improvement since initial treatment. The data of this pilot study suggest that IMD may be a feasible alternative to OP for treatment of acute wheezing episodes in children with asthma. IMD provides sufficient treatment to prevent clinical deterioration within 5 days after initial therapy for mild to moderate pediatric exacerbations of asthma that are responsive to nebulized medications. 相似文献
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