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101.
BACKGROUND: Individuals with chronic kidney disease have a high mortality rate after acute myocardial infarction. It is not known how frequently these individuals are prescribed combination cardioprotective therapy and if survival is affected by such therapy after acute myocardial infarction. METHODS: A retrospective cohort study of 1,342 Medicare recipients with acute myocardial infarction. Data were collected by medical chart abstraction as part of the Cooperative Cardiovascular Project in 60 hospitals in North Carolina during 5/30/1996-12/28/1997. We categorized cardioprotective medication use as aspirin alone, aspirin with beta-blockers, and aspirin with beta-blockers and ace-inhibitors. Chronic kidney disease was defined as a derived glomerular filtration rate (GFR) ranging from 15-89 mL/min/1.73 m2. Cox proportional hazards regression analyses were performed to determine the effect of cardioprotective medication use on survival while controlling for potential explanatory variables. RESULTS: The prevalence of cardioprotective medication use differed among levels of chronic kidney disease. Those with severe kidney disease (GFR 15-29 mL/min/1.73 m2) were less frequently prescribed aspirin with beta-blockers, 27.1%, and only 8.6% were prescribed aspirin with beta-blockers and ace-inhibitors. Survival was improved with prescribed cardioprotective medication use. In severe kidney disease (GFR 15-29 mL/min/1.73 m2), the hazards risk for death was 0.21 (0.08, 0.53) for aspirin alone, 0.17 (0.06, 0.51) for aspirin with beta-blockers, and 0.35 (0.09, 1.42) for aspirin with beta-blockers and ace-inhibitors. CONCLUSIONS: Individuals with chronic kidney disease benefit from combination cardioprotective therapy, but are less likely to be prescribed them after acute myocardial infarction. Further investigation is warranted to identify possible reasons for these observed treatment disparities. 相似文献
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We report a rare case of granulocytic sarcoma of the breast presenting as an isolated breast lump antedating bone marrow manifestation of acute myelogenous leukaemia. 相似文献
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Adsorbed proteins influence the biological activity and molecular targeting of nanomaterials. 总被引:1,自引:0,他引:1
Debamitra Dutta Shanmugavelayutham Kamakshi Sundaram Justin Gary Teeguarden Brian Joseph Riley Leonard Sheldon Fifield Jon Morrell Jacobs Shane Raymond Addleman George Alan Kaysen Brij Mohan Moudgil Thomas Joseph Weber 《Toxicological sciences》2007,100(1):303-315
The possible combination of specific physicochemical properties operating at unique sites of action within cells and tissues has led to considerable uncertainty surrounding nanomaterial toxic potential. We have investigated the importance of proteins adsorbed onto the surface of two distinct classes of nanomaterials (single-walled carbon nanotubes [SWCNTs]; 10-nm amorphous silica) in guiding nanomaterial uptake or toxicity in the RAW 264.7 macrophage-like model. Albumin was identified as the major fetal bovine or human serum/plasma protein adsorbed onto SWCNTs, while a distinct protein adsorption profile was observed when plasma from the Nagase analbuminemic rat was used. Damaged or structurally altered albumin is rapidly cleared from systemic circulation by scavenger receptors. We observed that SWCNTs inhibited the induction of cyclooxygenase-2 (Cox-2) by lipopolysaccharide (LPS; 1 ng/ml, 6 h) and this anti-inflammatory response was inhibited by fucoidan (scavenger receptor antagonist). Fucoidan also reduced the uptake of fluorescent SWCNTs (Alexa647). Precoating SWCNTs with a nonionic surfactant (Pluronic F127) inhibited albumin adsorption and anti-inflammatory properties. Albumin-coated SWCNTs reduced LPS-mediated Cox-2 induction under serum-free conditions. SWCNTs did not reduce binding of LPS(Alexa488) to RAW 264.7 cells. The profile of proteins adsorbed onto amorphous silica particles (50-1000 nm) was qualitatively different, relative to SWCNTs, and precoating amorphous silica with Pluronic F127 dramatically reduced the adsorption of serum proteins and toxicity. Collectively, these observations suggest an important role for adsorbed proteins in modulating the uptake and toxicity of SWCNTs and nano-sized amorphous silica. 相似文献
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Puri GD Dutta A Chinnan NK Thingnam SK Sharma SK Chari P 《European journal of anaesthesiology》2005,22(11):834-838
BACKGROUND AND OBJECTIVE: We studied the effect of different recumbent positions (supine, left and right lateral decubitus), on arterial oxygenation in 42 valvular heart disease patients planned for cardiac surgery. All patients had cardiomegaly (cardiothoracic ratio > or = 0.5) in their chest X-rays. Their left ventricular end-diastolic diameter was also noted from the preoperative echocardiogram. METHODS: Arterial blood gas analysis was performed in supine, left and right lateral positions after keeping the patient in a given position for 15 min. During this period all patients received 35% oxygen supplementation. RESULTS: Arterial oxygen tension and haemoglobin saturation were significantly higher in the right lateral position (PaO2 = 120.6 +/- 29.5 mmHg, SaO2 = 98.1 +/- 1.4%) than in supine (PaO2 = 111.0 +/- 30.6 mmHg, SaO2 = 97.6 +/- 2.2%) and left lateral positions (PaO2 = 109.7 +/- 32.0 mmHg, SaO2 = 97.6 +/- 1.7%; mean +/- SD; P 0.05). The change in PaO2 and SaO2 with change of posture from left to right was significantly related to left ventricular end-diastolic diameter (r = 0.50 and r = 0.63, respectively; Pearson correlation). Repeated measures of analysis of variance with left ventricular end-diastolic diameter as a covariate showed a significant change in arterial PaO2 with posture (P = 0.011). CONCLUSION: Right lateral posture improves arterial oxygenation in the valvular heart disease patient with an enlarged left ventricle. In the preoperative period, these patients may benefit from a right lateral posture when lying in bed. 相似文献
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Small bowel atresia is associated with a large size discrepancy between the proximal and distal segments of bowel that has traditionally been managed by resection of the dilated segment, tapering enteroplasty, or plication. Longitudinal intestinal lengthening is rarely performed at the time of the initial operation. Many patients with small bowel atresia also have a short length of residual small intestine secondary to in utero resorption. The authors present the clinical application of the novel intestinal lengthening procedure, the serial transverse enteroplasty, in a neonate with proximal jejunal atresia and suggest that it become part of the armamentarium for surgeons treating patients with this anomaly. 相似文献
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