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D A Morrow E M Antman S M Snapinn C H McCabe P Theroux E Braunwald 《European heart journal》2002,23(3):223-229
AIMS: We evaluated the TIMI Risk Score for Unstable Angina and Non-ST Elevation Myocardial Infarction for predicting clinical outcomes and the efficacy of tirofiban in non-ST elevation acute coronary syndromes. METHODS AND RESULTS: Developed in TIMI 11B, the risk score is calculated as the sum of seven presenting characteristics (age > or =65 years, > or =3 cardiac risk factors, documented coronary disease, recent severe angina, ST deviation > or =0.5 mm, elevated cardiac markers, prior aspirin use). The risk score was validated in the PRISM-PLUS database (n=1915) and tested for interaction with the efficacy of tirofiban+heparin vs heparin alone. The risk score revealed an increasing gradient of risk for death, myocardial infarction or recurrent ischaemia at 14 days ranging from 7.7-30.5% (P<0.001). Dichotomized at the median, patients with a score > or =4 derived a greater relative risk reduction with tirofiban (P((Interaction))=0.025). Among patients with normal creatine kinase myocardial bands, the risk score showed a 3.5-fold gradient of risk (P<0.001) and identified a population that derived significant benefit from tirofiban (RR 0.73, P=0.027). CONCLUSION: The TIMI Risk Score is a simple clinical tool for risk assessment that may aid in the early identification of patients who should be considered for treatment with potent antiplatelet therapy. 相似文献
84.
Donald A. Weiner Carolyn McCabe David C. Hueter Thomas J. Ryan William B. Hood 《American heart journal》1978,96(4):458-462
To determine the significance of anginal chest pain during exercise testing, a series of 302 patients undergoing coronary arteriography with exercise testing was reviewed. Of the 302 patients, 85 had ischemic ECG changes and chest pain (Group I); 87 patients had ischemic ECG changes but no chest pain (Group II); 25 patients had chest pain but no ischemic ECG changes (Group III); 105 patients had neither chest pain nor ischemic ECG changes (Group IV). Coronary artery disease was present in 95 per cent of Group I, 75 per cent of Group II, 72 per cent of Group III, and 28 per cent of Group IV. Of those patients with coronary disease, multiple vessels were involved in 94 per cent of Group I, 51 per cent of Group II, 67 per cent of Group III, and 21 per cent of Group IV. The predictive value for presence and extent of coronary disease showed Group I > Groups II and III > Group IV (p < 0.025). We conclude that (1) anginal chest pain during exercise testing predicts the presence and extent of coronary disease more accurately than its absence; (2) the presence of chest pain even without an ischemic ECG response during exercise testing appears to be as predictive of coronary disease as an ischemic ECG response alone; and (3) the combination of anginal chest pain during exercise testing and an ischemic ECG response is highly predictive of multivessel coronary artery disease. 相似文献
85.
Two kinds of erythrocytes are released in the blood of irradiated adult hybrid mice grafted with parental fetal liver cells: fetal antigen- bearing erythrocytes (Ft+ cells) and adult-type Ft- erythrocytes. Both are of parental origin, as determined by immune lysis using histocompatibility alloantigens. The latter cells make up all the recipient's red blood cells 2 mo after receipt of the graft, Ft+ cells then being no longer detected. The transient duality of erythropoiesis in irradiated adults grafted with fetal liver cells has been confirmed by studying the kinetics of CFU-E populations, as characterized by their ability to give rise to Ft+ or Ft- erythrocytes. The results are discussed in terms of environmental factors that influenc erythroid differentiation. 相似文献
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Assessment of aldehyde dehydrogenase in viable cells 总被引:3,自引:4,他引:3
Jones RJ; Barber JP; Vala MS; Collector MI; Kaufmann SH; Ludeman SM; Colvin OM; Hilton J 《Blood》1995,85(10):2742-2746
Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations. 相似文献
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Katherine JP Schwenger Johane P Allard 《World journal of gastroenterology : WJG》2014,20(7):1712-1723
Non-alcoholic fatty liver disease(NAFLD)ranges from simple steatosis to nonalcoholic steatohepatitis(NASH),leading to fibrosis and potentially cirrhosis,and it is one of the most common causes of liver disease worldwide.NAFLD is associated with other medical conditions such as metabolic syndrome,obesity,cardiovascular disease and diabetes.NASH can only be diagnosed through liver biopsy,but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis,reducing the need for liver biopsy and risk to patients.Disease progression varies between individuals and is linked to a number of risk factors.Mechanisms involved in the pathogenesis are associated with diet and lifestyle,influx of free fatty acids to the liver from adipose tissue due to insulin resistance,hepatic oxidative stress,cytokines production,reduced very low-density lipoprotein secretion and intestinal microbiome.Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD.Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial.Omega 3 polyunsaturated fatty acids and statins may offer additional benefits.Bariatric surgery should be considered in morbidly obese patients.More research is needed to assess the impact of these treatments on a long-term basis.The objective of this article is to briefly review the diagnosis,management and treatment of this disease in order to aid clinicians in managing these patients. 相似文献