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71.
Advances in myocardial perfusion imaging have firmly established the use of noninvasive techniques capable of providing useful information over a broad range of diagnostic and therapeutic cardiovascular problems. Evaluating regional myocardial perfusion abnormalities is a cornerstone for the diagnosis of coronary artery disease, risk assessment in those with known disease, and determination of myocardial viability. The clinical use of myocardial perfusion imaging and the current limitations of existing techniques continue to promote the development of new technologies capable of assessing microvascular and capillary perfusion abnormalities on a global myocardial level. Myocardial contrast echocardiography is an emerging technique capable of rapidly assessing myocardial perfusion at the capillary level in many different clinical settings. This article focuses on myocardial contrast-enhanced ultrasound perfusion techniques, emphasizing the unique information this modality provides compared with other noninvasive perfusion imaging techniques.  相似文献   
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Neopterin is known in humans as a sensitive marker for diseases associated with increased activity of the cellular immune system. Recent studies report neopterin also to exhibit distinct effects: neopterin induces inducible nitric oxide synthase expression in rat vascular smooth muscle cells and activates translocation of nuclear factor- kappa B. Neopterin may also induce oxidative stress causing apoptotic cell death, or superinduce tumor necrosis factor- alpha -mediated apoptosis. Observing these effects in cell cultures, we were interested in possible consequences of neopterin on cardiac function in the isolated perfused rat heart. The influence of neopterin in three different concentrations (10 micromol/l, 50 micromol/l, 100 micromol/l) on cardiac contractility parameters and coronary vascular resistance were studied in 67 male Sprague-Dawley rats using the temperature-controlled and pressure-constant Langendorff apparatus with retrograde perfusion of the aorta with a Krebs-Henseleit buffer. Treatment with 100 micromol/l neopterin resulted in a significant decrease in coronary flow and cardiac contractility. Coronary flow decreased from 15.2 to 9.5 ml/min (P=0.002), left ventricular pressure from 80 to 52 mmHg (P=0. 002), rate of pressure fall from 1605 to 923 mmHg/s (P=0.001) and rate of pressure rise from 2862 to 1709 mmHg/s (P=0.001). Concentrations lower than 100 micromol/l neopterin had no significant effect on cardiac function. Our study demonstrates a considerable influence of exogenous neopterin on cardiac performance in the Langendorff model of isolated perfused rat hearts. This has to be considered a potential pathogenic factor of cardiac disturbances in diseases in which high concentrations of neopterin are released due to immune activation. At present the exact mechanism remains unclear.  相似文献   
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Vartio  T; Hedman  K; Jansson  SE; Hovi  T 《Blood》1985,65(5):1175-1180
Cultured adherent human macrophages and a promonocytic cell line, U 937, were previously shown to produce a Mr 95,000 gelatin-binding protein. The protein has no immunologic cross-reactivity with the well- characterized gelatin-binding protein fibronectin and the Mr 70,000 gelatin-binding protein produced by a variety of mesenchymal or epithelial cell types (T. Vartio et al, J Biol Chem 257:8862, 1982). In the present study the Mr 95,000 protein was found in Triton X-100 extracts of granulocytes purified from human blood buffy coat. The protein, as isolated by gelatin-agarose, was immunologically cross- reactive with the corresponding macrophage protein in immunoblotting assay. When peripheral blood and bone marrow cells were examined for the presence of the Mr 95,000 protein by indirect immunofluorescence, positive staining was detected only in differentiated granulocytes but not to any significant extent in metamyelocytes, myelocytes, promyelocytes, or in normal or leukemic blasts. In granulocytes the protein had a granular cytoplasmic distribution. In freshly prepared monocyte cultures, the Mr 95,000 protein was detected in low amounts in the cytoplasm, while along with differentiation of the cells into macrophages, the immunofluorescence increased in a reticular and vesicular cytoplasmic pattern and in a juxtanuclear cap, probably representing the Golgi complex. In conclusion, the Mr 95,000 gelatin- binding protein was specifically detected in macrophages and granulocytes and may thus serve as a differentiation marker for these phagocytic cells.  相似文献   
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Objective

Hyponatremia is a complication of diuretic treatment and has been recently identified as a novel factor associated with osteoporosis and fractures. The impact of diuretic-associated electrolyte disorders on osteoporotic fractures (OF) has rarely been studied systematically.

Design and setting

We conducted a study in patients presenting to the emergency department at the University Hospital Bern. In this retrospective case series analysis of prospectively gathered data, over a 2-year period we identified 10,823 adult (≥50 years) outpatients with a measured baseline serum sodium, at admission to the hospital. OF patients were compared to a control group without fractures using standard statistical methods.

Results

Four hundred and eighty (5%) patients had 547 OF. The OF group had a higher mean age (73 vs. 68 years, p < 0.0001), smaller proportion of men (37% vs. 58%, p < 0.0001), higher hospitalisation rate (83% vs. 62%, p < 0.0001) and longer hospital stay (8 vs. 6 days, p < 0.0001). Any diuretic agent (p < 0.0001), loop diurietics (p = 0.02), spironolactone (p = 0.02) and amiloride (p < 0.01) were used significantly more in OF patients, but not thiazides (p = 0.68). The prevalence of hyponatremia increased significantly (p < 0.0001) with the number of diuretics taken. Advanced age (odds ratio [OR] 1.04, p < 0.0001), hyponatremia (OR 1.46, p = 0.011) higher serum creatinine (OR 1.53, p = 0.0001), furosemide use alone (OR 1.40, p = 0.01) and co-treatment with amiloride (OR 2.22, p = 0.02) were associated with a higher risk for OF.

Conclusions

This study highlights the clinical association of hyponatremia during the use of certain diuretics (i.e. furosemide or in combination, i.e. amiloride) with an increased risk of osteoporosis associated fractures. Although evidence-based data is currently lacking a pragmatic approach concerning hyponatremia monitoring and correction appears reasonable in selected groups of patients.  相似文献   
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